Polymers in Electronics: Market Report

Polymers in Electronics Market Report Keith Cousins

A Smithers Group Company

Polymers in Electronics Market Report

Keith Cousins

Smithers Rapra Limited A wholly owned subsidiary of The Smithers Group Shawbury, Shrewsbury, Shropshire, SY4 4NR, United Kingdom Telephone: +44 (0)1939 250383 Fax: +44 (0)1939 251118 http://www.rapra.net

Published in 2006 by

Smithers Rapra Limited Shawbury, Shrewsbury, Shropshire, SY4 4NR, UK

©2006, Smithers Rapra Limited

All rights reserved. Except as permitted under current legislation no part of this publication may be photocopied, reproduced or distributed in any form or by any means or stored in a database or retrieval system, without the prior permission from the copyright holder. A catalogue record for this book is available from the British Library. Every effort has been made to contact copyright holders of any material reproduced within the text and the authors and publishers apologise if any have been overlooked.

ISBN-10: 1-84735-006-2 ISBN-13: 978-1-84735-006-0

Typeset by Smithers Rapra Limited Cover printed by Telford Reprographics Limited, Telford, UK Printed and bound by Smithers Rapra Limited, Shrewsbury, UK

Contents

1. Introduction ........................................................................................................................... 1 1.1

Background ................................................................................................................... 1

1.2

The Report .................................................................................................................... 1

1.3

Methodology ................................................................................................................. 2

2. Executive Summary ................................................................................................................ 3 3. Review of Materials and Properties ...................................................................................... 11 3.1

Introduction ................................................................................................................ 11

3.2

Polymers for Components ........................................................................................... 13 3.2.1

Acrylonitrile-Butadiene-Styrene (ABS) ........................................................... 13

3.2.2

Acetal Copolymers (Polyoxymethylene; POM) .............................................. 13

3.2.3

IXEF Polyarylamide ...................................................................................... 14

3.2.4

Liquid Crystalline Polymers (LCP) ................................................................ 14

3.2.5

Polyamide (Nylon; PA) .................................................................................. 15

3.2.6

Polybutylene Terephhalate (PBT) ................................................................... 15

3.2.7

Polycarbonate (PC) ........................................................................................ 16

3.2.8

Poly Ether Ether Ketone (PEEK) .................................................................... 17

3.2.9

Polyetherimide (PEI) ...................................................................................... 17

3.2.10

Polyethylene Naphthalate (PEN) ................................................................... 18

3.2.11

Polyethylene Terephthalate (PET) .................................................................. 18

3.2.12

Polyparaphenylene Terephthalamide ............................................................. 18

3.2.13

Polyimide (PI) ................................................................................................ 18

3.2.14

Polypropylene (PP) ........................................................................................ 19

3.2.15

Polyphthalamides (PPA) ................................................................................ 19

3.2.16

Polyphenylene Sulfide (PPS) ........................................................................... 19

3.2.17

Polystyrene (PS) ............................................................................................. 20

3.2.18

PS-Modified Polyphenylene Oxide (PPO) ...................................................... 20

3.2.19

Polysulfone (PSU) .......................................................................................... 20

3.2.20

Polytetrafluoroethylene (PTFE) ...................................................................... 20

3.2.21

Polyurethane (PU) ......................................................................................... 21

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Polymers in Electronics

3.2.22

Polyvinyl Chloride (PVC) .............................................................................. 21

3.2.23

Polyvinylidine Fluoride (PVDF) ..................................................................... 21

3.2.24

Styrene/Acrylonitrile (SAN) ........................................................................... 22

3.2.25

Elastomers ..................................................................................................... 22

3.2.26

Conductive Materials .................................................................................... 22

3.2.27

Additives ....................................................................................................... 23

3.3 Component Characteristics ............................................................................................. 23 3.4 Polymers for Enclosures .................................................................................................. 25 3.5 Electronic Components - Polymers Typically Employed.................................................. 26 3.5.1

Batteries including Lithium Polymer Types .................................................... 26

3.5.2

Capacitors ..................................................................................................... 29

3.5.3

Coil Formers ................................................................................................. 31

3.5.4

Connectors .................................................................................................... 32

3.5.5

Membrane Keypads ....................................................................................... 35

3.5.6

Plugs and Sockets .......................................................................................... 35

3.5.7

Printed Circuit Boards (PCB) ......................................................................... 36

3.5.8

Relays ............................................................................................................ 38

3.5.9

Resistors ........................................................................................................ 39

3.5.10

RFI Screening ................................................................................................ 40

3.5.11

Sensors .......................................................................................................... 40

3.5.12

Switches ........................................................................................................ 41

3.5.13

Terminals....................................................................................................... 42

3.5.14

Touch Screens ................................................................................................ 42

4. Overview of European Electronic Component Markets ........................................................ 45

ii

4.1

Introduction ................................................................................................................ 45

4.2

Market Analysis .......................................................................................................... 45

4.3

Mobile Communications ............................................................................................. 46

4.4

Automotive Applications ............................................................................................. 48

4.5

Fuel Cells..................................................................................................................... 51

4.6

Computers................................................................................................................... 53

4.7

Contract Electronic Manufacturing ............................................................................. 53

4.8

Component Distribution ............................................................................................. 54

4.9

European Markets – Germany..................................................................................... 55

Contents

4.10 European Markets – France......................................................................................... 56 4.11 European Markets – Italy ............................................................................................ 56 4.12 Other European Markets............................................................................................. 57 5. Key Trends and Developments.............................................................................................. 59 5.1

Bluetooth Technology .................................................................................................. 59

5.2

Organic and Other Polymer Developments ................................................................. 59

5.3

Supercapacitors ........................................................................................................... 61

5.4

Solar Cells ................................................................................................................... 63

5.5

Flat Panel Displays ...................................................................................................... 64

5.6

Other New Technologies ............................................................................................. 70

5.7

Recycling ..................................................................................................................... 75

5.8

Chemical Safety ........................................................................................................... 77

5.9

Compliance with European RoHS and WEEE Directives ............................................ 77

5.10 Nanotechnology .......................................................................................................... 81 6. Company Profiles ................................................................................................................. 85 Arkema ................................................................................................................................. 85 Basell BV .............................................................................................................................. 85 BASF AG .............................................................................................................................. 85 Bayer AG .............................................................................................................................. 86 Borealis A/S .......................................................................................................................... 87 BP plc ................................................................................................................................... 88 CDT Limited ........................................................................................................................ 88 Degussa AG .......................................................................................................................... 89 Dow Europe GmbH ............................................................................................................. 90 DSM Engineering Plastics BV ............................................................................................... 90 Dupont (UK) Limited ........................................................................................................... 91 EMS-chemie (UK) Limited .................................................................................................... 93 Epcos AG ............................................................................................................................. 93 General Electric Company .................................................................................................... 94 Huntsman Corporation ........................................................................................................ 95 LG Chem .............................................................................................................................. 96

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Polymers in Electronics

Plastic Logic Limited ............................................................................................................ 97 Rogers Corporation .............................................................................................................. 98 SABIC Europe ...................................................................................................................... 98 Samsung Electronics ............................................................................................................. 99 Solutia Inc. ........................................................................................................................... 99 Solvay Chemicals Limited ................................................................................................... 100 Teijin 101 Ticona GmbH..................................................................................................................... 102 Toray Europe Limited (TEL)............................................................................................... 103 Total SA.............................................................................................................................. 104 TT Electronics plc ............................................................................................................... 105 Tyco Electronics UK Limited .............................................................................................. 106 Victrex plc .......................................................................................................................... 106 7. Future Outlook ................................................................................................................... 109 7.1

Optical Applications.................................................................................................. 109

7.2

Search for New Products ........................................................................................... 109

7.3

Superconducting Plastics ........................................................................................... 111

7.4

Asia - Opportunity or Threat .................................................................................... 112

8. Abbreviations and Acronyms .............................................................................................. 115

iv

1

Introduction

1.1 Background According to a study commissioned by PlasticsEurope (Brussels, Belgium) the sales turnover of the West European plastics industry in 2004 was €275 billion with Germany responsible for more than a quarter of the overall figure which includes machinery sales and sales by plastics processors. In terms of the production of plastics, the West European figure of 53.3 million tonnes represented around 24% of world production whereas the percentage figure for Asian production was 35.5% and that for North America was 26%. Usage of plastics in the European electronics sector is relatively small since it is largely confined to passive components where the annual value of the components sold has been valued at €3.78 billion. As will be seen from this report there has been some migration of electronics manufacturing from Europe to Asia leading to reduced demand. Consequently the reduction of electronics manufacture in Europe has been a significant factor in the decline of component sales in Europe in the three subsequent years after 2000. However, a small 3% recovery was reported in 2004. Furthermore, the industry has been particularly hit by falling prices resulting from Asian and American competition where, in the latter case, the falling value of the dollar had a significant effect. Despite some increases in unit sales, albeit at unattractive prices, manufacturers still found themselves with spare manufacturing capacity. The pattern of polymer usage has changed and material formulations have had to be modified to conform with new European Union (EU) legislation relating to the use of hazardous materials in components. Furthermore there is now far more emphasis on recycling rather than landfill disposal and these are issues covered in the report.

1.2 The Report This report seeks to provide an overall picture of the varied use of polymers in the manufacture of electronic components. It has endeavoured to identify trends and future movements of the market. Section 2 consists of an Executive Summary with brief notes on the properties and applications of the most commonly used polymers by the component makers forming the basis of Section 3. Section 4 is an overview of European Electronic Component Markets and goes on to review the major component users which are the telecommunications sector boosted by its constituent mobile phone sector, the automotive sector because of the increasing electronics content of new models when compared with their predecessors, the increasingly important fuel cell sector and the information technology (IT) sector. Contract electronics manufacturing continues to be important in a world context but cost pressures are moving operations to Asia and other low labour cost locations. This section also identifies issues of significance in individual European markets.

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Polymers in Electronics

Section 5 considers key trends and developments affecting the current and future use of polymers in electronic component applications including their use in flat panel displays, nanotechnology applications and solar cells. Plastics recycling is also discussed. Section 6 comprises a selection of company profiles of the leading suppliers and consumers in this sector. The future outlook, especially the search for new polymer applications in the components sector is reviewed in Section 7. The question of whether Asia represents an opportunity or threat is also considered.

1.3 Methodology This report has been compiled largely by the extensive use of desk research including company annual reports and press releases from the internet together with the resources of Rapra Technology’s database. I would also like to express my thanks for the help I received from many company and trade association representatives I met at trade exhibitions, and to those companies who responded to my requests for information.

2

2

Executive Summary

Designers of electrical and electronic components have a wide choice of polymers at their disposal and this report lists the most commonly used with brief notes on their properties. One of industry’s main concerns is the implementation of the European Restriction of Hazardous Substances (RoHS) 2002/95/EC directive. The regulations relate to eight distinct categories of equipment including, for example, consumer electronics which comprises such items as television sets, audio equipment, video recorders and digital cameras. Products must not contain any of the following substances in excess of the prescribed levels of 0.01% for cadmium and 0.10% for lead, mercury, hexavalent chromium, polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE). The implementation of the legislation heralds the arrival of a new generation of lead-free solders and solder paste whose melting points are around 34 ºC higher than their predecessors. This change dramatically affects the selection of polymers for specific applications. Polymer suppliers have risen to the challenge by changing product formulations to comply with the new requirements. Cost and competition are imposing ever more stringent specification criteria on the equipment designer who, in turn, is demanding significantly improved performance from his polymer supplier. The role of mineral fillers in plastic compounds is changing. In the past they were used to reduce costs by replacing polymer content by a less expensive material. Now they have a more important role to play since their use can modify processing characteristics or the properties of the finished part. Other uses include their ability to reduce the content of more expensive additives, notably pigments, flame retardants and impact modifiers. Nanotechnology is extending its influence to many areas of electronics with the UK reported to be a global leader in commercialising nanotechnology. Nanomaterials are coming to the fore as potential fillers along with the more traditional options of alumina trihydrate, barium sulfate, calcium carbonate, kaolin and talc. The UK Government’s Science and Technology Minister, Lord Sainsbury, speaking in late 2005, valued the UK’s current annual turnover for all micro and nanotechnologies at £11 billion adding that it supported around 20,000 jobs. The British Standards Institution (BSI) Director, Mike Low stated that the global nanotechnology market was expected to reach £16.7 billion ($29 billion) by 2008. In 2004, the European Union provided funding of £1.7 billion ($3 billion) for nano-related projects. This represented almost a third of the £5.7 billion ($10 billion) sum spent globally by the public sector and private organisations. The component manufacturers’ problems have been compounded by rising oil prices which have fed through into higher polymer prices. This problem has been highlighted in a recent survey by the British Plastics Federation (BPF) [1] and reported in the February 10th 2006 issue of the Financial Times, which cited average October 2005 price rises of 58% in gas and 56% in electricity. Furthermore, polymer manufacturers have been imposing price increases due largely to the rise in the cost of oil. More recently BPF surveyed its members and reported to the UK government that up to 7,000 jobs

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Polymers in Electronics

could be lost in the plastics and rubber industry if the government does not provide help in reducing energy bills. The survey reported that rising energy costs were resulting in 48% of member companies having to resort to redundancies with 54% of companies reducing investment programmes by an average of 31%. The climate change levy was also having an adverse effect. More compact electronic designs are often accompanied by heat dissipation problems; these have been addressed by the greater use of thermally conductive polymers. Electrically conductive polymers also have their place and are maybe one solution for components whose outer cases must act as a protective screen against the passage of electromagnetic (EMI) or radio frequency interference (RFI). The screening is necessary to ensure compliance with European Electromagnetic Compatibility (EMC) legislation with products bearing the CE mark to denote compliance. The EMC directives were adopted to ensure that equipment is able to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to other equipment in that environment. The annual worldwide demand for polyamides has grown to around six million tonnes. They are selected for component use because of their good chemical, electrical and mechanical properties, flexibility and relative immunity to fracture. They are inherently fire resistant without the use of flame-proofing agents and achieve a UL 94 [2] classification of V2 to V0. Brief peak temperatures of up to 200 ºC are possible because of heat ageing stabilisation. Similarly named but physically different polyimides (PI) are noted for their heat resisting properties, high mechanical strength, excellent electrical properties and superior chemical resistance. The possible working temperature range extends from –269 ºC to +400 ºC. They are expensive and may be difficult to process but are widely used in electronics applications, notably printed circuit boards (PCB), especially flexible PCB substrates, and capacitor and transformer insulation. Thermosetting polyimides have also been developed. Polycarbonate (PC), the material of choice for optical disks is also extensively used in electronic applications because it is rigid and dimensionally stable. China has changed from being, essentially a polycarbonate non-player in 1998, when it accounted for 5% of global demand, to being the leading consuming country five years later when it accounted for 25% of global demand. In future Chinese companies will certainly raise their profile as in the case of the Chinese company Lenovo’s acquisition of IBM’s personal computer business. Other Asian countries with higher cost levels than the major manufacturing countries in the region still manage to compete and Malaysia, for example, is expanding its production of plastic parts for electronic components. It is difficult to come to terms with the consequences of gross domestic product (GDP) growth of 8% per year in China where the economy is forecast to maintain this growth rate over the next few years. China’s population is currently around 1.3 billion and its annual consumption of plastics products is approximately 1 kg per head compared with a 40 kg per head figure for Western Europe. Most components are produced by injection moulding where ever smaller parts demand ever tighter moulding tolerances and such factors as freedom from shrinkage, warpage, creepage and water absorption. These constraints effectively limit the choice of polymers for specific applications. Further constraints in some applications include the use of halogen-free flame retardant materials, again limiting the choice of polymer. Consequently an electrical connector manufacturer, for example, will offer products moulded from different polymers depending on the end-use of product in which the connector is being used. For example, a budget design may use polystyrene (PS) whereas a top-ofthe-range model may be made from polyether ether ketone (PEEK).

4

Executive Summary

The European Union market for electronic components, according to the industry’s European Component Manufacturers Association (EECA), is dominated by three countries which collectively account for 61% of the total 2004 market which the association stated was €47.7 billion. Germany leads, with a national market of around €12.79 billion, followed by the UK with a market size of around €10.73 billion and France with an approximate figure of €5.57 billion. In 2004 sales of passive components were €3.78 billion thus accounting for approximately 8% of European components sales with the semiconductor sales of €31.7 billion representing a share of around 66.5%. Analysed by application the largest market in 2004 for electronic components in Europe is the computing sector with a market size of €13.51 billion which represents a 29% share of the overall market. The communications market, especially mobile phones, was the second largest and amounted to €10.97 billion or 23% of the market. It was followed by automotive where the figure of €9.15 billion represented a 19% share. Consumer and industrial categories, accounted for €6.5 billion and €6.2 billion, respectively, with market shares of 14% and 13%. US sales of consumer electronics products exceeded $135 billion in 2005 and may be seen as a pacemaker for trends on this side of the Atlantic. The average US household is reported to own 25 consumer electronics products ranging from digital cameras and mobile phones to large screen digital television sets. In the UK 2005 sales of TV sets were reported to be 4.5 million units with a rising trend to large screen digital models. The overlap between the two large screen digital television set technologies is increasing as liquid crystal display (LCD) screens get bigger and plasma screens appear in smaller sizes. Development of the LCD backlighting technology continues, with researchers in Japan producing what is claimed to be a highly efficient thin backlight (HSOT-II) with an array of microprisms at its base, in a direction parallel to that of a cold cathode fluorescent lamp. The polymer used in the backlight is polymethylmethacrylate (PMMA) containing spherical silicone microparticles. Unlike LCD, with their backlighting, the pixels in a plasma display are light sources in their own right. Consequently as the screen size shrinks, the pixels are smaller and generate less light resulting in a picture lacking in brightness. All these products contain electronic components, many with a significant polymer content. One of the major businesses driving the market at the present time is mobile communications. Despite apparent market saturation in parts of Europe the number of mobile phone users worldwide was believed to have exceeded two billion by the end of 2005, a year in which sales grew by an estimated 21% with 795 million mobile handsets being shipped. This figure represents incredible year-on-year growth from the estimate of 280 million units in 1999. The number of mobile phone subscribers is expected to rise to three billion by the end of 2008. Today’s typical mobile phone handset, will have a plastics content of approximately 40% though this figure rises to 75% if calculated on the basis of weight. Since 1992 the average weight of a mobile phone is said to have fallen 500 g to today’s figure of 100 g. Polymers used in a typical mobile phone include acrylonitrile-butadiene-styrene (ABS) or PC for the outer case because of their weight reducing qualities and their durability. Good transparency is imperative for the screen for which PC or PMMA may be chosen. Connector manufacturers have several options with polybutylene terephthalate (PBT) and polyamide (PA) providing stability. For safety reasons elastomers provide the raw material for antennas. PCB base material is invariably an epoxy resin because it offers heat resistance and design flexibility. The components themselves may

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Polymers in Electronics

be made using PA, PBT or polyethersulfone (PES) which deliver a superior performance in terms of insulation and heat resistance. The customers for electronic components manufacturers can be categorised in four major ways, catalogue distributors, contract equipment manufacturers (CEM), original equipment manufacturers (OEM) and overseas distributors. One important market is the battery sector and polymer use here can be categorised in three distinct ways. For example the polymer may be used in the manufacture of the battery separators used in traditional cells to provide physical separation of the positive and negative plates whilst permitting electron flow through the electrolyte. Polyester and polypropylene (PP) fibres may also be used to reinforce the battery plates themselves in traditional cells. The second function is as a battery container material which must resist chemical attack by the electrolyte and give the container mechanical strength. Rechargeable lithium-ion polymer cells incorporate the polymer as part of the electrochemical operation of the battery and these cells are widely used to power such portable consumer products as laptop computers and mobile phones. Lithium-metal-polymer is a relatively new technology from Avestor in Canada. It uses a solid polymeric electrolyte obtained by dissolving a lithium salt in an appropriate co-polymer. The metallic oxide cathode is made from a plastic composite material. Not only are polymers being used for power storage but they are also being used for memory storage as has been demonstrated by researchers at Princeton University in collaboration with Hewlett-Packard Laboratories in the US. The inherently conductive polymer, polyethylene dioxythiophene (PEDOT), also known as Oligotron, is used to make a memory which is technically a hybrid because it contains a plastic film, a flexible foil substrate and some silicon in the form of PEDOT organic conducting polymer dots on the surface of a thin film inorganic silicon diode. Components which use polymers include capacitors where non-impregnated metallised film designs incorporate polyester or polypropylene film. High temperature designs may employ polytetrafluoroethylene (Teflon; PTFE) which gives an operating temperature of up to 200 ºC. Tolerance of high temperatures is now a pre-requisite for PCB. One of the critical properties when selecting printed circuit board laminate materials is its glass temperature transition point (Tg). High temperature FR-4 (Flame Resistant 4) material has a Tg of 150 ºC, continuous operating temperature of 130 ºC, and will also withstand temperatures of between 260 ºC and 280 ºC for brief periods. However the use of polyimides will permit continuous operation at elevated temperatures. In selecting suitable PCB material it is necessary to bear in mind that it will usually have to withstand at least three exposures to high temperature during the solder reflow process. One to each side of the board and a third after post-testing rework. Whilst the mouse is the preferred control option of many personal computer users, touch-screens are increasingly being used in industrial and other applications including hospital patient care systems, gaming machines and computer installations in post offices and restaurants. The various control technologies are resistive, surface wave, projected and surface capacitance, and infrared. However, not all the systems invariably involve the use of polymers. Those which do include the resistive system whereby a clear acrylic, PC or glass substrate is attached to a second flexible polyester layer.

6

Executive Summary

Another major market for electronic components is the automotive industry where, currently, plastics represent around 13% of the total weight of a medium-sized car and industry experts believe that 90% of future car design improvements and innovations will have an electronic content. Looking ahead to 2007 it is forecast that plastics will represent around 18% of the car’s total weight. Around 80% of the car weight, on average, is recycled and this is mainly metal with plastics and rubber frequently being sent to landfill. The End-of-Life Vehicles Directive has aimed to reduce the quantity of material disposed of in this way by setting specific targets for recycling and recovery. Consequently it is most important that vehicle designers take future dismantling and recycling into consideration at the design stage. Polymers are used in fuel cells. Those of particular interest are the polymer electrolyte membrane (PEM) and the phosphoric acid fuel cell (PAFC) designs. The latter design contains the liquid phosphoric acid in a Teflon bonded silicon carbide matrix. In March 2005 Ticona reported that it had built the first fuel cell prototype made solely with engineering thermoplastics. They claimed that this approach reduced the cost of the fuel by at least 50% when compared with fuel cells fabricated from other materials. The 17-cell unit contains injection moulded bipolar plates of Vectra liquid crystal polymer and end plates of Fortron polyphenylene sulfide (PPS). These two materials remain dimensionally stable at temperatures up to 200 ºC. The Vectra LCP bipolar plates contain 85% powdered carbon and are made in a cycle time of 30 seconds. The most popular fuel cell design for prototype road vehicles and fork lift trucks is the PEM type which converts the fuel directly into electricity with only water vapour as an exhaust gas. The electrolyte is a solid organic compound in the form of a paper-thin membrane which is sandwiched between an electrically negative anode catalyst and an electrically positive cathode catalyst both of which are composed of platinum particles. Toyota claims to be the first fork lift truck manufacturer to develop a hydrogen powered hybrid fuel cell model. It incorporates double-layer capacitors designed to maximise efficiency by smoothing out the numerous interruptions in current output and input, arising from frequent stopping and starting, and the contribution of regenerative braking. In looking at key trends and developments it is interesting to note that environmental concerns are now influencing the electronic components market. The Japanese Pioneer Corporation is now making optical storage disks using corn-starch-derived polylactic acid (PLA) which, unlike PC, is obtained from the fermentation of biomass and which is almost totally biodegradable when buried in soil. Toray Industries is also making PLA, branded as Ecodear. It has, in collaboration with Fujitsu Ltd and Fujitsu Laboratories Ltd, produced what has been claimed to be the world’s first large plastic case, using PLA resin, for Fujitsu’s FMV-Biblio NB80K notebook computer. Bayer is linked to the electronics industry via its HC Starck subsidiary which supplies the Baytron P transparent conductive polymer which can be used to manufacture organic light-emitting diodes (OLED). Innovative developments by the US Plextronics conductive polymer company include an OLED designed to compete with incandescent and fluorescent lamps. The company is also working on solar cells where inherently conductive polymers are the key ingredients to replace silicon. Super-capacitors, which are capable of storing up to a hundred times more energy than traditional capacitors, act like batteries but without the handicap of equivalent series resistance (ESR). They are able to deliver high pulses of power with charge-up and discharge times which can be measured in seconds. Operating voltages tend to be between two and three volts. It is therefore necessary to

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Polymers in Electronics

connect them in series with the addition of circuitry to ensure voltage sharing between individual units. The fundamental basis of super-capacitor design is to have two activated carbon electrodes immersed in an organic electrolyte. The electrodes are separated by a membrane which permits mobility of ions whilst preventing electronic contact. The range of available electrodes now includes metal oxides and conducting polymers. Super-capacitors have minimal contact resistance because the conducting polymers can be synthesised directly on to the current collector. The electrode material can be formed as thick films, powders or sub-micron coatings with the latter offering the possibility of diffusion times of the order of microseconds. Another polymer sales growth area is the market for solar cells where year-on-year rises culminated in a 27% increase in the photovoltaic market in 2005 when the world solar cell market was reported to be worth around five billion dollars. One technology making great strides is that based on polymer light emitting diodes (PLED) and which are claimed to be the fastest growing new technology destined to replace LCD liquid crystal displays according to its leading developer, Cambridge Display Technology (CDT). CDT’s technology may also be used in reverse to act as a photovoltaic cell and CDT has filed several patents in this area. Fundamentally they relate to the use of light emitting polymer (LEP) technology for display applications. The LEP displays are produced by the application of a thin film of the LEP on to a glass or plastic substrate which has been coated with a transparent indium tin oxide electrode. A metallic electrode is deposited on top of the polymer. Thereafter the application of an electric field between the two electrodes results in the emission of light from the polymer. This technology was invented at Cambridge University which jointly with the inventors founded CDT to patent, develop and exploit the technology. CDT has stated that its fundamental patent is unopposed worldwide. Rapid prototyping is a growing products and services market and uses computer aided design (CAD) technology. The CAD data is then used by numerically controlled machine tools to produce the actual component from material in billet form. Polymers used for this process include acetal, ABS, PC, polypropylene and polyamide. An alternative approach to rapid prototyping is to use the technology of stereolithography (SLA) which is capable of plus or minus 0.1 mm per 100 mm. SLA involves the use of a beam of UV light to solidify the flow of liquid photopolymer resin which is controlled by instructions produced by a CAD system. The process builds up the prototype slice by slice. In 2005, Philips, which invests around 10% of its sales income on research and development, claimed a new research breakthrough with a polymer-based memory which is non-volatile, that is to say it will not lose data when the power supply is switched off. The technology involves the use of a field-effect transistor in which the gate dielectric is composed of a polymer ferro-electric material. Applications include the ability to make low-cost radio-frequency identification tags (RFID), a product which is being widely introduced into logistics and retail businesses with reported world production estimates of some 1.3 billion tags in 2005. Polymer recycling is not a regular feature of the plastics industry, with only 6.3% of plastics used in the UK being recycled, so there is considerable pressure to increase this figure. In an interesting development, reported in the 25th November 2004 issue of Japan Chemical Week, it was stated that the Japanese NEC electronics group is recycling power station fly ash in a flame retardant PC resin manufacturing process.

8

Executive Summary

Profiles of some leading polymer suppliers and components are included together with information on the materials supplied to this sector.

References 1.

Energy Crisis Hits Plastics Hard, BPF Press Release, 05/06, 8th February 2006.

2.

UL 94, Tests for Flammability of Plastic Materials for Parts in Devices and Appliances, 2003.

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Polymers in Electronics

10

3

Review of Materials and Properties

3.1 Introduction Competition from low cost Asian producers and rising raw material prices due largely to the increasing costs of oil, gas and electricity is putting European manufacturers under severe pricing pressure. Consequently, when a supplier offers a new product which claims to meet existing specification requirements at an appreciably lower price then the buyer will definitely give it serious consideration. Many such products will fulfil their claimed performance figures but some will not and buyers are advised to be wary of wonder products from far off lands, though any supplier may make spurious claims for his products. In other cases the improved performance may come at an unacceptable price. For example a content of up to 50% glass fibre may result in excessive tool wear. The role of mineral fillers in plastic compounds is changing. In the past they were used to reduce costs by replacing polymer content by a less expensive material. Now they have a more important role to play since their use can modify processing characteristics or the properties of the finished part. Other uses include their ability to reduce the content of more expensive additives, notably pigments, flame retardants and impact modifiers. Nanomaterials are coming to the fore as potential fillers along with the more traditional options of alumina trihydrate, barium sulfate, calcium carbonate, kaolin and talc. According to one market research company, NanoMarkets, growth in demand for plastics in electronics applications will be driven by the conductive polymers and flexible substrates sectors reaching worldwide demand figure of 5.8 billion US dollars by 2009. The implementation of the RoHS European Union directive which, amongst its other provisions, outlaws lead-based solder, heralds the arrival of a new generation of lead-free solders and solder paste whose melting points are around 34 ºC higher than their predecessors. This change dramatically affects the selection of polymers for specific applications and polymer suppliers have risen to the challenge by changing the formulations of certain produce to comply with the new requirements. The lead-free solder adopted by manufacturer Texas Instruments is a nickel-palladium-gold (NiPdAu) formulation which is claimed to be backward compatible with existing reflow soldering processes. It is also claimed to be free of the ‘whisker-artifact’ problems which have been experienced when using such alternatives as matted tin. A Texas Instruments spokesman stated that the move to pure tin would necessitate the increase of the reflow solder temperature to obtain the same reliable solder contacts. He claimed that Texas Instruments had shipped more than 30 million lead-free units which confirmed the suitability of its NiPdAu solution. The UK Cookson Group’s, Cookson Electronics subsidiary has negotiated licences with the patent holders of various lead-free solders. These enable it to manufacture globally and supply them as a patent holder, making royalty payments on sales. The alloys concerned are Senju Sn/Ag/Cu (Senju-

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Polymers in Electronics

Matsushita), Iowa State University Research Foundation ‘ISURF Sn/Ag/Cu, Oatey Safe Flo (for example 96.0 Sn/2.5 Ag/1.0 Bi/0.5 Cu) and Aim’s CASTIN alloy 96.2 Sn/2.5 Ag/0.8 Cu/0.5 Sb. No royalty is payable on Cookson ALPHA Vaculoy SACX0307 since Cookson itself holds the patent for this alloy. The 96.5 Sn/3.5 Ag alloy composition is readily available for use because it has no patents associated with it. One of the consequences of higher soldering temperatures is that far greater attention must be paid to moisture sensitivity levels. The problem can be particularly evident in surface mount components which are encapsulated in plastic, since to a certain extent, all such packages have a tendency to absorb moisture from their surroundings. Subsequently the solder reflow process used in PCB assembly may produce a dramatic reaction, known as the ‘popcorn effect’, due to rapid expansion of the moisture within the package which then bursts with resulting physical damage. The problem is avoided by purchasing components in vacuum-sealed moisture-controlled packs which have to be stored in a controlled environment after being opened. The use of the components is then governed by the supplier’s instructions as printed on the packaging. In any event it is important to choose the right encapsulant to protect components from contamination, humidity and shock. Cyanoacrylates and epoxies are commonly used as encapsulating and conformal coating materials. The selection of polymers for component use is governed by the need to manufacture, cost-effectively, a high quality product in volume at high speed with daily production volumes up to 30,000 units. The criteria needed in the selection process are: 1.

Wall thicknesses are frequently less than 1 mm so the polymer must have good melt flow properties during the moulding process without sacrificing performance in other respects.

2.

Having designed the wall thickness to be less than 1 mm the resulting product must have the necessary mechanical strength to fulfil its design purpose. Within the normal parameters of wear and tear, products made from plastics will have a service life of between five and twenty years though many will have been discarded or replaced by then.

3.

Dimensional stability is important so shrinkage and warpage should be minimal since typical tolerances are below 5 μm. This feature is particularly important in the case of PCB material.

4.

Flame resistance to be secured by the use of halogen-free flame retardants where possible.

5.

The need to solder components calls for the material to have high thermal stability since the temperature of solder baths is around 270 ºC and the reflow soldering process involves brief exposure to high temperatures.

6.

The material must be resistant to any chemicals which may splash or immerse the component. These typically include hydraulic oils, cleaning agents and lubricants.

7.

In view of the occasional need for sliding components to work within an enclosure, such sliding should not produce dust and so good tribological qualities are required. These qualities can

12

Review of Materials and Properties

be varied by the selective use, for example, of additives and modifiers including PTFE powder, silicone oil or molybdenum disulfide. PTFE is banned as a lubricant in some areas because of the ‘Blue Angel’ environmental standard. This German standard claims to be the first and oldest environment-related label in the world for products and services. Dating back to 1977 when it was created on the initiative of the Federal Minister of the Interior, the first six awards were granted in 1978 by the Environmental Label jury. Now around 3,700 products and services in 80 product categories, including mobile phones, carry the Blue Label insignia. 8.

Complex product geometry, readily attainable with thermoplastics, may be unavoidable in order to achieve the required product specification.

9.

The polymer’s electrical performance is also important in some applications where the resistivity and tracking performance figures may be laid down.

10. Humidity may be a problem in some instances because some polymers are subject to hydrolytic degradation which results in embrittlement.

3.2 Polymers for Components It should be borne in mind that all plastics experience thermal ageing, a process caused by exposure to heat over long periods. It effects are aggravated by external influences such as radiation or additional stress whether it be chemical, electrical or mechanical. It is possible to test samples of materials and obtain data which will assist, but not absolutely determine, the selection of appropriate polymers for specific applications. In case of electrical strength the guideline standard is the material’s relative thermal index (RTI) value as referred to in UL 746B [1]. The Ti value or mechanical strength, using the criterion of a 50% reduction in tensile strength after 20,000 hours operation, is covered in IEC 60 216-1 [2]. The Ti temperature value for the material should not be exceeded by the sum of the ambient temperature and the rise in temperature when the component is in use.

3.2.1 Acrylonitrile-Butadiene-Styrene (ABS) ABS is claimed to be the engineering resin most used when measured in terms of sales volume. Mainly used in the automotive industry, its second largest user sector is the electronics sector where it is a popular choice, especially for the production of intricate parts. ABS has good dimensional stability at both high and low temperatures and ABS may be coated with metallic surfaces, for example nickel. Its UL 94 [3] flammability classification is from HB to V0. Many manufacturers, who offer different grades according to the end use, include BASF (Terluran), Dow (Magnum) and Polimeri Europa (Sinkral).

3.2.2 Acetal Copolymers (Polyoxymethylene; POM) Acetal copolymers (POM) are widely used and have a melting point of 163 ºC whereas the related acetal homopolymers have a higher melting point of 175 ºC with greater mechanical strength. However, POM is a strong enough material to be used for the manufacture of coil formers and plastic

13

Polymers in Electronics

fasteners of all types where it is resistant to attack by oxidation and where it has a high recovery rate against attack from solvents and fuels. POM has good wear and electrical properties and is resistant to creep. Manufacturers include BASF (Ultraform).

3.2.3 IXEF Polyarylamide This product family, which is a form of Nylon, includes some of the stiffest thermoplastics available which are claimed to have properties almost equal to metal. Applications include their growing use in the mobile phone chassis where, despite the case getting smaller and lighter in weight there is still a need for stiffness in order to protect the contents. Manufacturers include Solvay Advanced Polymers whose IXEF polyarylamide has a Tg of 85 ºC with a surface finish which is claimed to be excellent. IXEF is also used in other applications where extra stiffness and precision are needed notably connectors, switches, housings, motor end frames and telecommunication parts.

3.2.4 Liquid Crystalline Polymers (LCP) The molecular structure of liquid crystalline polymers is one of their characteristic features. It comprises rigid, rod-like macromodules which align in the melt to produce liquid structures. Although more expensive than some competing polymers, LCP possess better flow characteristics to fill the thin walls of modern connectors, for example. With continuous service temperatures up to 240 ºC (short-term up to 340 ºC) LCP also possess the improved thermal performance needed by PCB to withstand the high temperatures experienced during the soldering process. LCP are sufficiently tough to accept interference-fit loading of contacts without cracking and also provide the opportunity to speed up cycle times. The toughness should also be sufficient to prevent protruding catches (or other projecting items) from breaking away. Solvay Advanced Polymers states that its XYDAR LCP, which may be reinforced with glass, glass/mineral or just mineral filled, has the highest heat deflection temperature (HDT) of any thermoplastic, with an inherent resistance to virtually all chemicals together with unmatched processing capability. Other features of LCP include very low melt viscosity, flash-free injection moulding, very high tensile strength, very high plastic modulus in the flow direction together with high impact strength and inherent flame retardancy. For the most demanding electronics application the American Quantum Leap Packaging Inc., has developed LCPh, a new class of LCP which is capable of withstanding temperatures in excess of 400 ºC. Ticona’s Vectra LCP range for injection moulding, includes a variety of grades based on a number of basic polymers. The grades differ in their melting point, heat resistance, rigidity and flow characteristics. Furthermore, by compounding with various fillers and reinforcing materials, it is possible to tailor the product specification to meet the requirements of many different applications. LCP are fully aromatic copolyesters or copolyesteramides which have become the standard high performance polymers used in certain new electrical/electronic applications notably fuel cells. Thermosetting LCP are also available.

14

Review of Materials and Properties

3.2.5 Polyamide (Nylon; PA) The annual worldwide demand for polyamides has grown to around six million tonnes. They are selected for use in electrical components because of their good chemical, electrical and mechanical properties, flexibility and relative immunity to fracture. They are inherently fire resistant without the use of flame-proofing agents and achieve an Underwriter’s Laboratory, UL 94 [3] classification of V2 to V0. Brief peak temperatures of up to 200 ºC are possible because of heat ageing stabilisation. A number of types including PA4.6, PA6.6 and PA6.10 are available to the designer and melting points are in the band which extends from 215 ºC to 295 ºC. Polyamide absorbs moisture from its surroundings with levels of around 2.8% being attained. However, this moisture is found as chemically bonded H2O groups within the molecular structure, a feature which gives the plastic flexibility and resistance to breakage, even at temperatures as low as –40 ºC. However glass fibre reinforced polyamides, which have greater rigidity and hardness than non-reinforced grades, absorb less moisture. Fibre-reinforced PA has a UL classification from V2 to V0. However V0 material is usually only available in black. T-gard-5000, from Laird Technologies, is a high temperature polyamide film with a ceramic-filled conformal coating and is used in applications where the properties of electrical insulation and thermal conductivity are required simultaneously. This could be a requirement for electronic components attached to an aluminium heat sink, for example. The dimensional stability of polyamides may be inadequate for interconnected parts. DSM’s Stanyl PA46 Nylon, made from adipic acid and 1,4-diaminobutane has high temperature resistance which renders it suitable for such products as memory connectors, I/O input/output connectors, board-to-board and wire-to-wire connectors, modular jacks and micro-switches where temperatures of up to 280 ºC may be encountered during post processing, especially during soldering. The material has exceptional flow properties and high weld line strength which are said to establish its superiority over LCP. Other qualities include very high toughness and very high stiffness with very low creep. Technical superiority over other engineering plastics, notably PA6, PA6.6, polyesters, polyphthalamide (PPA), semi-aromatic polyamides and PPS is also claimed for Stanyl by virtue of its better heat resistance, better mechanical properties at elevated temperatures together with better wear and friction behaviour. The manufacturers also claim faster cycle times, increased flowability and improved processing economics. Interestingly, Stanyl is the first thermoplastic to be used in aero engine components by Rolls-Royce which has used it in parts for the Trent 900 engine which will power the world’s largest plane, the Airbus A380. Other manufacturers include BASF whose Ultramid grades include PA6, PA6.6, PA6.66 and PA6.6T.

3.2.6 Polybutylene Terephhalate (PBT) Often seen as a substitute for metals and thermosets, PBT is an increasingly successful polymer which is used, both in non-reinforced and fibre-reinforced variants, in components because of its high dimensional stability, good surface finish, good electrical and mechanical properties and absence of

15

Polymers in Electronics

dioxin or furan forming substances. Some PBT grades have better flow performance which enables much smaller parts to be moulded. PBT brands include Celanex from Ticona and Crastin from DuPont. PBT will endure high operating temperatures and its UL 94 flammability classification is from V2 to V0. Fillers used with PBT include carbon or stainless steel fibres, fibreglass and mica. Other brands include Ultradur from BASF.

3.2.7 Polycarbonate (PC) The optical disk market is a major PC consumer and, according to Bayer Material Science, it accounts for 800,000 tonnes out of a global market of around 2.4 million tonnes. In the UK, compact disks (CD) and digital video disks (DVD) are frequently given away with newspapers and there is a vast market for DVD versions of popular films with the film, Shrek 2 generating worldwide sales of approximately 40 million optical disks. Injection moulded PC components have an important role in electrical and electronic applications because the material is rigid and dimensionally stable, has a high impact resistance, a wide temperature range, a good resistance to chemicals and, also, the further option of transparency. It also has good insulation properties. Furthermore, in some applications, PC is seen as an alternative to glass and it has been reported that around 80% of vehicle headlamps are now made from PC. Whereas PC has good resistance properties against mineral acids, saturated aliphatic hydrocarbons, petrol, greases and oils, it is less resistant to solvents, benzene, alkalis, acetone and ammonia. Strain cracks may occur after contact with certain chemicals. Its UL 94 flammability classification [3] is in the range from V2 to V0. In Japan Idemitsu Kosan has developed a PC, with what is claimed to be world’s highest level of heat resistance, which is being offered for optical and electronic applications. With a minimum Tg of 250 ºC, this figure is claimed to be the highest of all transparent, thermoplastic resins. Furthermore this PC can withstand soldering and can be processed into film. It is also highly soluble and so can be used as a base material in heat resistant paints and inks. Typical standard PC brands include Calibre from Dow, Lexan from GE Plastics, Makrolon from Bayer, and Xantar from DSM. Glass fibre reinforcement may be incorporated to improve rigidity and, to this end, it has been reported that the Japanese Asahi Fiber Glass Co. Ltd., has developed a special glass fibre to produce a compound which combines transparency with a low coefficient of expansion. Applications include personal computer and other housings as infrared sensor, transparent display covers. PC may be blended with ABS to produce a rigid material with a good appearance and good flow properties. In Japan the growing use of PC/ABS blends, the use of PC for optical disks and its use in housings resulted in record 2004 domestic consumption of PC of 255,800 tons, an increase of 10.2% on 2003 figure. Teijin Chemicals, in 1982, was one of the first companies in the world to use high-purity PC for the manufacture of CD. Now it is one of the world’s leading manufacturers of polycarbonate resin for the manufacture of digital video disks DVDs. In the opinion of Teijin, the PC market can be considered as two separate entities, general purpose and advanced products. Teijin has opted to serve the advanced products sector where applications include mobile phones, DVD players and liquid crystal display television sets.

16

Review of Materials and Properties

China has changed from being, essentially a PC non-player in 1998, when it accounted for 5% of global demand, to being the leading consuming country five years later when it accounted for 25% of global demand. Teijin Chemicals aims to be Asia’s leading supplier of PC resin and world number three in capacity terms. In April 2005, Teijin Polycarbonate China Limited completed the construction of a new 50,000 tons/year PC polymer plant. A similar production line is being constructed at the plant which will double the plant’s output capacity after its scheduled opening in December 2006. Elsewhere in China, Teijin Chemicals Plastic Compounds Shanghai Limited began full-scale production at its 20,000 tons/year plant in the Autumn of 2004. A second production line came on stream in October 2005. Asian producers have been wary of installing new plant capacity in view of the over-supply situation between 2001 and 2003 when a 40% manufacturing increase resulted in change from net annual imports of 300,000 tons to net annual exports of 200,000 tons. Industry investment plans in 2005 were based on annual demand growth of between 7% and 9% up to 2009 whereas the actual annual demand growth averaged 11% between 1988 and 2004. This situation led LG-Dow Polycarbonate to carry out a 2005 feasibility study into the construction of a second 65,000 tons per year PC production line. Bayer has certainly benefited from the increasing demand for PC with sales of €1.9 billion in the first three quarters of 2005, a 34.8% increase over the comparable period in 2004. Higher prices made a major contribution to this rise. New PC/ABS blends include one with good thermal and mechanical qualities from the US Stratasys company. It has been specifically developed for rapid prototyping and rapid production. The benefit to electronic component and other manufacturers is the ability to model with the same material as that which will be used to make the end-product.

3.2.8 Poly Ether Ether Ketone (PEEK) PEEK is a semi-crystalline polymer, insoluble in all common solvents and can be used at temperatures of up to 300 ºC. This is a particular benefit when it is used in applications which involve the use of lead-free solder. The polymer has excellent chemical and mechanical stability. Victrex has achieved success in the Asian market with PEEK, which has been selected by Shoei, a Japanese capacitor and miniature rechargeable battery manufacturer and distributor, to replace PPS resin in all the resin mould cases of its PetitCap aluminium electrolytic capacitors. PEEK-HT (high temperature polymer), which maintains its physical and mechanical properties at temperatures 30 ºC higher than standard grades, has been introduced by Victrex.

3.2.9 Polyetherimide (PEI) PEI is a tough amorphous thermoplastic resin, with good mouldability and chemical resistance, marketed by GE Advanced Materials as ULTEM. PEI is one of the intrinsically flame resistant polymers used to manufacture injection moulded PCB and self-extinguishing component casings. One of the latest additions to GE’s PEI portfolio is ULTEM XHT which the manufacturer has developed to be ‘the highest heat, injection mouldable, amorphous resin on earth’. Its features are that it combines extremely high heat resistance, high chemical resistance, flame retardance, transparency and stability. It can be moulded using existing equipment and is seen as a potential replacement for glass, metal and other high heat-resistance materials.

17

Polymers in Electronics

3.2.10 Polyethylene Naphthalate (PEN) PEN film, branded as Teonex by Teijin is widely used for high-density storage tapes and other applications in the automotive sector. Teijin is also developing a nanocomposite PEN and recently inaugurated new coated film facilities incorporating nanotechnology for the production of Optfine which is now being sold as an anti-reflective film for displays.

3.2.11 Polyethylene Terephthalate (PET) PET is the polymer which has had one of the largest demand growth rates in recent years though to a major extent this is probably due to its use as glass substitute in bottle manufacture. PET may be reinforced with around 30% glass fibre and is one of the materials used in flexible printed circuits. In other applications where higher temperatures are likely to be encountered, flame retardant PET may be used. High-density polyethylene (HDPE) is typically used to produce push-in cable tie clips for insertion in pre-drilled holes in wood masonry and other materials. It is also used in the cable clips with small pre-fitted nails to enable cables to be clamped to masonry, wood and plaster surfaces. Polyethylene (PE) is also used as the material to mould bushings which insulate the rough cut conduit ends in flexible moulded cable and flexible metallic conduit. To meet the increasing demand for clear, thick PET film for use in flat panel displays (FPD) Teijin is to install new production facilities at its Gifu plant in Japan. This will come into operation in the third quarter of 2006.

3.2.12 Polyparaphenylene Terephthalamide Marketed by Teijin as Aramica this engineering film with a para-aramid structure features superb rigidity and modulus which is reported to be amongst the highest found in organic films. Other properties are reported to be high heat resistance similar to that of polyimide, with heat stability similar to that of ceramics. Consequently these properties facilitate the production of thinner circuit boards and lighter weight components than polyimide film which is reported to have been the preferred choice to date. Applications include fine chip on film components and layer insulating and reinforcement materials.

3.2.13 Polyimide (PI) Although polyimides, obtained from the reaction of dianhydrides and diamines, were discovered in 1908 they were only commercially launched as thermoplastic, polymeric materials in the early 1960s, notably by DuPont which markets them under the Kapton and Vespel brands with composite film being marketed as Oasis. The main features of PI are their heat resisting properties, high mechanical strength, excellent electrical properties and superior chemical resistance. The possible working temperature range extends from –269 ºC to +400 ºC.

18

Review of Materials and Properties

Although they are expensive and may be difficult to process, they are widely used in electronics applications, notably (PCB), especially flexible PCB substrates, and insulation in capacitors and transformers. Thermosetting PI, with processability and solvent resistance, have also been developed. More recent applications include the development by the Chinese Academy of Sciences (CAS) of photosensitive BTPA-1000 and standard BTDA-1000 polyimide special resins for super large very large scale integration cladding materials. The academy has reported that some semiconductor producers and research institutes are planning to use these new resins in the production of chips and photoelectric components. With the financial support of the National 863 Program for Hi-Tech Development from the Chinese Ministry of Science and Technology the research team, led by Professor Yang Shiyong of the CAS Institute of Chemistry (ICCAS) has developed proprietary production technology for manufacture of these special resins.

3.2.14 Polypropylene (PP) Polypropylene is a relatively low cost material available in different grades for different applications and is claimed to be a thermoplastic with a well-balanced relationship between toughness, stiffness and hardness with the additional benefits of high heat resistance, excellent resistance to chemicals, low water absorption and permeability to water vapour, easy and flexible to process and of low density. These qualities enable PP to be used for a wide variety of electrical and electronic applications including battery containers, cable retention clips, screws, nuts and washers.

3.2.15 Polyphthalamides (PPA) PPA offers the user higher operating temperatures and superior physical properties with PPA injection mouldings being selected to replace metal alloy diecastings. Suppliers include Solvay Advanced Polymers whose AMODEL PPA family provides high temperature performance at over 260 ºC, dimensional stability, strength and ease of processing.

3.2.16 Polyphenylene Sulfide (PPS) PPS is a crystalline engineering plastic especially known for its high heat performance with heat deflection temperatures in excess of 260 ºC. It has exceptional processability when injection moulded on conventional equipment. It also has outstanding dimensional stability and so is particularly suitable for precision moulding to severe tolerances. It can also be used as a replacement for high performance thermosets or metal, especially brass, in some applications. PPS is primarily used for surface mounted connectors and optical pick-up units but it is also replacing conventional materials in such applications as housings for mobile phones and other mobile information devices. New product grades include Ryton R-4-260 PPS from Chevron Phillips Chemical Co., which is a glass-filled PPS for electronics applications. Its properties include low flashing and low outgassing tendencies.

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Polymers in Electronics

3.2.17 Polystyrene (PS) World polystyrene manufacturing capacity was reported to be approximately 20.4 million tons in 2004 with consumption running at around 17.3 million tons. China, already amongst the largest PS consumers with consumption in 2004 of 3.8 million tons, is increasing its manufacturing capability to reduce imports which were reported to be 1.563 million tons in 2004.

3.2.18 PS-Modified Polyphenylene Oxide (PPO) PPO is a tough rigid polymer with good dimensional stability when subjected to high temperatures and humidities. However, because it is reputedly difficult to process it may be blended to facilitate injection moulding. It is sometimes seen as a substiute for metal diecastings. PS-modified polyphenylene oxide is produced by GE plastics and marketed under the trade name Noryl. Applications include UL 94 V-0 flame retardant [3] PCB enclosures and glass-fibre filled self-extinguishing UL 94 V-1 relay bases. The latter application permits 600 V operation with an operating temperature of 110 °C and a short-term tolerance of 135 ºC.

3.2.19 Polysulfone (PSU) Polysulfone, is sold by Solvay Advanced Polymers as Udel and by BASF as Ultrason S. It may be 30% glass filled and can also be blow or injection moulded, extruded or thermoformed. It is a tough, rigid, high-strength thermoplastic with a 174 ºC heat deflection temperature. Polyethersulfone (PES) is a related polymer, which may also have a 30% glass fibre content, which is exemplified by BASF’s Ultrason E grade. These are relatively expensive engineering polymers with good chemical and heat resistance. They have good dimensional stability with constant electrical and mechanical properties over a wide temperature range. The excellent surface quality of PSU enables it to be metallised directly. Comparative testing has revealed that the mechanical properties of PSU and PES at temperatures over 140 ºC are far superior to those of PPS and PC for example.

3.2.20 Polytetrafluoroethylene (PTFE) Polytetrafluoroethylene is a fluoropolymer. The market for fluoropolymers worldwide is reported to be around 100,000 tonnes of which approximately 40% is consumed in the US and approximately 10% is consumed in Japan. PTFE accounts for some 70% of total demand for fluoropolymers which are increasingly being used because of their outstanding qualities. Fluoropolymers are unique amongst polymers in respect of their chemical and thermal stability, biocompatibility, water resistance and superb dielectric properties, having a dielectric constant of 2.1. Other members of the Teflon family include a polymer of tetrafluoroethylene and hexafluoropropylene (FEP) and a polymer of tetrafluoroethylene and perfluorovinylether (PFA). The 327 ºC melting point of PTFE is reputed to be one of the highest in organic polymer chemistry. The melting points of FEP and PFA are 260 ºC and 305 ºC, respectively.

20

Review of Materials and Properties

PTFE is used in connectors and printed circuits, especially in hostile environments calling for heavy duty models. It can also be used to produce computer chip packages and shielding gaskets where it can be used in an expanded form. The selection of PCB material is determined by the end use application, and to achieve the required performance, ceramic filled PTFE composites, with or without the addition of woven or non-woven glass fibre, may be used. PTFE may also be used in heavy duty electrical connectors. It can also be used when connectors are moulded on to cables.

3.2.21 Polyurethane (PU) Unlike the status of other polymers, an international polyurethane industry conference and exhibition, UTECH 2006, was held in Maastricht in the Netherlands at the end of March as a means to promote increased use of the polymer. More than 130 exhibitors, representing the major manufacturers and suppliers took part. Polyurethanes available for electronic components include Baydur CSP from Bayer which is claimed to offer high dimensional accuracy and the ability to provide complex geometries, variable wall thicknesses and excellent surface reproduction when moulded. PU and epoxy resin potting compounds are used to encapsulate electronic devices and their components to give them enhanced mechanical and electrical stability as well as providing protection from moisture, thermal or physical shock and vibration. One interesting application for polyurethane, developed jointly by Puren, Bayer Material Science and Siemens, is for a new speaker-free ‘purSonic’ sound system which can be installed in walls, ceilings and floors. Basically, the system comprises a 7 mm thick PU soundboard, which is made from Bayer’s Desmophen and Desmodur. The system’s sound generator sets up vibrations in the soundboard rather than using conventional loudspeakers. Each soundboard is made to vibrate using flexural sound generators on the reverse side. These receive signals from a programmable digital processor which takes into account the properties of the surface materials behind which the soundboards are fitted, be they plaster, wallpaper or tiling for example.

3.2.22 Polyvinyl Chloride (PVC) PVC has come under the spotlight, as far as RoHS compliance is concerned, because alternatives to the traditional use of lead as a stabiliser must be found. Suitable alternatives include calcium/zinc stearates.

3.2.23 Polyvinylidine Fluoride (PVDF) Polyvinylidene fluoride, is a fluorinated semi-crystalline thermoplastic which has a continuous use service temperature of up to 150 ºC and a very low dielectric constant. Current manufacturers include Arkema which has become legally separated from its former owner, Total. PVDF applications include its use as fuel cell membrane material, film material in capacitors and as electrolyte material in sodium sulfur batteries. In the US, NASA has employed a crosslinked polystyrene sulfonic acid (PSSA)/PVDF composite as a PEM.

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Polymers in Electronics

3.2.24 Styrene/Acrylonitrile (SAN) Styrene/acrylonitrile copolymer has the properties of clarity and toughness. It is a stiff resin with good chemical resistance, high heat resistance and good dimensional stability having excellent processability and good surface finish. SAN is used in electrical components and suppliers include Bayer (Lustran), Dow (Tyril) and Polimeri Europa (Kostil). SAN can also be blended with other resins including ABS, PA and PC.

3.2.25 Elastomers There has been rapid growth in the market for thermoplastic elastomers (TPE) since they possess the advantages of vulcanised rubber in respect of their processability and their physical properties which may be seen as an ideal blend of plastic and rubber. Elastomers used for connector insulators include polychloroprenes, silicones, fluoro-silicones and heat-setting compounds which enable the special characteristics to be incorporated for example, flame resistance, low toxicity and low smoke. Neoprene is used as spacer material and also for washers where its sealing qualities, good resistance to cracking, rotting, oils and petrol and its good low temperature flexibility may be beneficial in specific applications. Silicone rubber is used for key pads of handheld devices, process controllers, access control panels, military communications and other equipment. Other options include the combination of plastic keytops with a rubber mat. Blending, alloying and compounding are especially important in the production of materials to fulfil demanding specifications These involve the addition of various fillers and reinforcements, including glass fibre, in order to build in the desired properties. The production of polymers for the component sector is a specialised business with dedicated suppliers.

3.2.26 Conductive Materials Some electronic components need to be electrostatically or electromagnetically screened and this can be carried out in a number of ways including treatment with conductive paint, electroless plating, vacuum deposition or by inserting a thin metal shield. Another option is to produce a compound incorporating carbon black or carbon fi bres. One such typical compound is 199X106847A from RTP in the US whose range of electrically conductive, carbon filled, high flow polypropylene grades is designed for the production of injection moulded, complex electronic, medical and biotechnical devices. The Cabot Corporation has introduced another conductive compound, Cabelec, in which carbon black has been dispersed into a modified polypropylene resin. The resulting permanent conductive and antistatic properties are unaffected by humidity or other environmental conditions. The compound can be injection moulded to produce components able to operate, in accordance with European ATEX 95 and ATEX 137, in potentially explosive environments.

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Review of Materials and Properties

The solution adopted by LNP Engineering Plastics in its electroconductive Faradex compounds, notably Faradex DS-1003 FR HI, has been to incorporate a balanced dispersion of stainless steel fibres (1%-2% by volume and 10%-20% by weight). This custom colourable, halogen-free fire resistant compound, based on Lexan EXL PC resin, provides both EMI shielding of between 20 dB and 60 dB and electrostatic dissipative qualities. Another approach to EMI screening involves the use of intrinsically conducting polymers (ICP), notably polyaniline and polypyrrole which can form the basis of composite materials whose composition may be tailored to the requirements of the application. Other conducting polymers include polyacetylene, polythiophene and poly-p-phenylene. Advantages of ICP include corrosion resistance, relatively low weight, processability and tunable conductivity. Some applications call for an electrically conductive adhesive. Masterbond offers EP21TDC/S Medical which is a two-component, electrically conductive, silver-filled tough epoxy adhesive with a high peel strength as well as low volume resistivity.

3.2.27 Additives An unusual use of additives with potential application in hospitals and other environments where cleanliness is paramount, is use of Microban antimicrobial technology. This is capable of killing various harmful bacteria including those responsible for methacillin resistant Staphylococcus aureus (MRSA) and Escherichia coli 0157 with independent tests showing a kill rate of 99% for these two microorganisms. The source of the new technology is MacDermid Autotype, where the antimicrobial protection is built into the hard-coat layer, which enables the protection to be built into traditional flat panel displays, membrane keypads, touch screens and fascia panels. The manufacturing process follows traditional lines and comprises a flexible polyester base, primed on the underside with an ink adhesion layer, for high definition screen and ink-jet printing, and coated on the outside with an exceptionally tough hard-coat layer. The hard-coat layer is scratch and chemical resistant though it can easily be embossed to produce tactile membrane switch domes. These can be selectively varnished to produce windows or specific graphical effects. The film itself has a total luminous transmission of 92% plus an excellent flex modulus and, according to the manufacturers, it has a typical tactile membrane switch dome life in excess of five million cycles.

3.3 Component Characteristics Components and enclosures are allocated an ingress protection (IP) number which denotes their protection against the ingress of foreign bodies or water as shown in Table 3.1. It is important to note that the IP rating is also affected by the method of fixing used, method of sealing and cable entries, not just the enclosure itself. A third digit relating to impact protection is occasionally used. This is defined in Table 3.2.

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Polymers in Electronics

Table 3.1 IP Number defined by selecting the first digit from the first column and the second digit from the third column First Degree of Protection against Ingress Second Degree of Protection against Ingress Digit of Solids Digit of Water 0

1

2

3

4

5

6

No protection against accidental contact, no protection against intrusion of solid foreign bodies. Protection against solid objects with diameter greater than 50 mm, hands or large tools for example Protection against solid objects with diameter greater than 12 mm, hands or large tools for example. Protection against solid objects with diameter greater than 2.5 mm, wire or small tools for example. Protection against solid objects with diameter greater than 1 mm, wires for example. Full protection against contact. Limited protection against interior detrimental dust deposition. Total protection against contact and ingress of dust.

0

No protection against water.

1

Protection against vertically falling water drips.

2

3

4

5

6 7 8

Protection against direct sprays of water up to an angle of 15º from the vertical. Protection against direct sprays of water up to angle of 60º from the vertical. Protection against water sprayed from any direction – limited ingress permitted. Protection against low pressure water jets from any direction – limited ingress permitted. Protection against high pressure water jets from any direction – limited ingress permitted. Protection against immersion between 15 cm and 1 m. Protection against long periods of immersion under pressure.

Table 3.2 Third Digit Relating to Impact Protection Third Digit 0 1 2 3 5 7 9

24

Protection against mechanical impact damage No protection Protected against 0.225 joule impact (150 g @ 15 cm) Protected against 0.375 joule impact (250 g @ 15 cm) Protected against 0.5 joule impact (250 g @ 20 cm) Protected against 2.0 joule impact (500 g @ 40 cm) Protected against 6.0 joule impact (1.5 kg @ 40 cm) Protected against 20.0 joule impact (5.0 kg @ 40 cm)

Review of Materials and Properties

3.4 Polymers for Enclosures Whereas metal pressings are normally suitable for enclosures in category 4, with cast aluminium providing better protection, plastics will often perform better, with the preferred polymers in the categories 5 and 6 tending to be PC and PS. For the greatest protection lids should be glued or attached using a sealant. However, where access to the interior of the enclosure is needed, more often a click or press fit of the lid may suffice. If bolts are used then grommets should be employed to give a better seal. In the case of IP54 sealing or greater it is usually necessary to employ a compressible seal between the lid and the body of the enclosure. Furthermore it is said that machine applied polymer seals perform better than gasket types. To achieve IP65 and higher protection it is necessary for the lid fixing screws to be situated outside the area enclosed by the lid seal. Ineffective sealing may give rise to component short circuits, corrosion and affect operational reliability. If there are significant ambient temperature variations then condensation may become a problem. Rolec offers an IP65 rated weather resistant polyTOP-Ex range which is manufactured from glass fibre reinforced polyester. This range is corrosion proof because the metal inserts are manufactured from stainless steel. The lid fixings can be specified as slot head or allen head screws. The polyKOM-Ex range features IP66 ingress protection and is also manufactured from glass fibre reinforced polyester with stainless steel metal inserts and lid fixings. The company has received atmosphere explosibles (ATEX) certification for these models to enable them to be used in hazardous environments. Another manufacturer, Hammond Electronics, offers five styles, each comprising sixteen size options, of small sealed IP66 compliant enclosures. Outdoor applications utilise PC, with the option of transparent lids, whereas ABS is used indoors. All enclosure lids have a poured gasket tongue and grooved seal. Portable electronic equipment of all types is invariably packaged within an enclosure which may be an off the shelf standard design or a customised special. The Soft Case range of tactile off the shelf designs from OKW has recently been launched. The novel cigar box shaped format incorporates a wide recessed area on the top to accommodate a wide format liquid crystal display or keypad. Additionally a raised panel on the wide edge of the base is design to accept installation of connectors for USB, power and serial interfaces. The cases can be supplied with or without a battery compartment to house two 1.5 V AAA cells. The moulded ABS (UL 94 HB) enclosure is designed to accept a 3 mm ring to increase the internal height. The 3 mm extra internal height may also be obtained by fitting a moulded TPE ring to provide IP54 protection and offer some protection if the box is bumped. Internal screw pillars, for the attachment of PCB, are provided in the top and base elements. Four self-tapping screws are used to complete the assembly of the enclosure. The requirements of the application, and price, will determine the selection of suitable polymers and a selection of these is shown in Table 3.3. Other polymers being promoted for use in enclosures include PVC and rigid PU. The latter may be cast at room temperature using a mixture of polyol resin and an isocyanate hardener. Benefits of the material include the ability to cast economically in small quantities with low cost tooling, coupled with the capacity to produce precise and complex three-dimensional components. Accuracy and repeatability are good, as is machinability and the facility for thick to thin wall sections. Injection moulded polyurethane is also used as a seal material between the enclosure and its cover. Castech TAG offers low volume, custom designed reaction injection moulded polyurethane enclosures using in house manufactured low-cost tooling.

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Polymers in Electronics

Table 3.3 Thermoplastics Used in the Manufacture of Electronic Components Generic Category Specific Products Applications Polycarbonate PC, ABS/PC Easy to machine, lightweight enclosures with good resistance to chemicals, wide temperature range, transparency option Enclosures for hostile Polyester atmospheres, good resistance reinforced with to chemicals, good temperature glass fibre range capability can be used both indoors and outdoors Plug cases. Enclosures with AcrylonitrileStyrene polymers ABS butadiene-styrene good resistance to chemicals, Typical grades: lightweight, normal temperatures. Copolymer UL 94 HB ABS can also be flame retardant UL 94 V0 Standard cases including wallSAN Styrene mounted versions Acrylonitrile Copolymer PMMA Flexiglass Where transparency is required Crystalline High heat and chemical polymers resistance, good dimensional stability and low melt viscosity. Note: Plug cases incorporate a built-in mains plug to enable the whole enclosure to be plugged into a suitable wall socket, as in the case of a switched mode power supply or compact charging unit for rechargeable batteries.

3.5 Electronic Components - Polymers Typically Employed 3.5.1 Batteries including Lithium Polymer Types The use of polymers in battery construction can be categorised in three distinct ways. For example the polymer may be used in the manufacture of the battery separators used in traditional cells to provide physical separation of the positive and negative plates whilst permitting electron flow through the electrolyte. Polyester and polypropylene fibres may also be used to reinforce the battery plates themselves in traditional cells. The second function is as a battery container material which must resist chemical attack by the electrolyte and give the container mechanical strength. Rechargeable lithium-ion polymer cells are also available from IBT, for use in such portable applications as mobile communications and hand-held instrumentation, with a nominal voltage of 3.7 V and capacities ranging from 100 mAh to 4500 mAh at the five hour discharge rate. The polymer may be part of the electrochemical operation of the battery as in the case of lithium polymer designs. The performance of traditional lithium-ion cells has more than doubled over the past ten years from 280 Wh/l (watt hour per litre) in 1995 to 580 Wh/l in 2005 as a result of changing the chemical

26

Review of Materials and Properties

formulation of anode and cathode. In current designs the anode is typically a graphite mixture, the cathode being composed of a blend of lithium, nickel and cobalt. Cost has been reduced and the robustness of the cells improved. These cells are now the dominant power sources in such portable consumer products as lap-top computers and mobile phones. In a new design technology from the Japanese NEC Corporation, the makers claim to have developed a flexible organic-radical rechargeable battery (ORB) which is less than 1 mm thick and which can be charged up to 90% of full capacity within 36 seconds. The battery can be recharged several thousand times before wearing out. The ORB is made from a special gel which is non-inflammable, non-explosive and which does not contain any material which is harmful to the environment. The battery’s key constituent is organic polytetramethylpiperidinyloxy methacrylate whose radicals are very stable in air and are oxidised to cations when the battery is charged. Subsequently, as the battery is discharging, they are reduced to the stable radicals. Prototypes of a 3.6 V battery can be charged with a power density of 10 kW/kg compared to the 1.0 kW/kg obtainable from a conventional lithium-ion design. NEC has already experimented with the possibility of using the ORB as a back-up power supply for desktop personal computers. Future trends include the adoption of a nickel-cobalt-manganese (NCM) cathode comprising a solid solution of nickel-cobalt-manganese. Further ahead, towards the end of 2006, the NCM will be replaced, by Panasonic, with the NCA, which is a blend of nickel-cobalt-aluminium dioxide. This development will increase the energy density to 620 Wh/l. Lithium-ion-polymer (LIP) cells, normally abbreviated to lithium polymer, are non-toxic and similar to lithium ion designs but are more expensive though lighter in weight. The nominal voltage of a LIP cell is 4.2 V and battery service life at room temperature is estimated to be three years although at higher temperatures of 50 ºC or even 60 ºC the service life would be significantly shortened. The charging regime of rechargeable cells should follow manufacturers’ recommendations. The main difference between conventional lithium ion and current lithium polymer types is that the former design has a liquid electrolyte whereas the latter design is, typically, a sandwich where the outer elements are gelled porous polymer electrolyte membranes with an interspersed porous polymer membrane with transition interfaces between the membrane layers. However, the liquid electrolyte feature of lithium ion batteries has been challenged by the Japanese Ohara company which has developed a flexible electrolyte which is a 150 mm wide, 50 μm thick sheet for such rechargeable batteries. The sheet is composed of glass ceramic powder, with lithium-ionic conductivity and organic polymer. Ohara believes that the transfer to solid electrolyte would enhance cell safety. The company also believes that potential applications for this type of electrolyte include thin-film cells used in integrated circuit (IC) cards and other electronic products. Initially, lithium polymer battery electrolytes were in the form of a dry solid polymer electrolyte but it was found that performance could be improved by introducing gelled electrolyte into the separator system. Described by some as a ‘gelionic’ electrolyte which is not a genuine polymer, these critics maintain that the batteries should be described as being ‘plastic’ lithium ion and not lithium polymer. Despite the apparent flexibility of lithium polymer batteries they should normally only be used flat and not even bent during the installation process into the device. However, it is possible to obtain batteries already moulded into certain shapes as, for example, in mobile phones where they can

27

Polymers in Electronics

be moulded to conform to the shape of the outer casing of the phone itself. In recent years these batteries have been reduced in size, thickness and weight. It is interesting to note that in comparison with a nickel cadmium battery of equivalent power rating the lithium ion polymer design may be up to 30% smaller and lighter. Lithium polymer cells with their outer aluminium cases are said to be inherently safer than lithium ion designs. The charging regime is safety critical and it is essential to use a battery charger whose performance is matched to the battery’s requirements. Lithium-metal-polymer (LMP) is a relatively new technology being promoted by the Canadian Avestor Limited Partnership based in Boucherville, Quebec, for telecommunications applications. Avestor’s LMP cell is built up from four elements. An ultra-thin metallic lithium foil anode combines the roles of lithium source and current collector. The solid polymeric electrolyte is made by dissolving a lithium salt in an appropriate co-polymer. The metallic oxide cathode is based on a reversible intercalation compound of vanadium oxide, blended with a lithium salt and a polymer to produce a plastic composite. Finally, an aluminium foil forms the current collector. Avestor cells can operate within the temperature range –40 ºC to +65 ºC. Avestor is producing two models for the telecommunications market. The SE 48S63 was launched in 2004 and is a 48 V DC, 63 Ah unit weighing 27 kg and measuring 404 mm long x 200 mm wide x 273 mm high. In October 2005 the company launched the SE 4880 which provides 80 Ah at 48 V DC in the same casing as the earlier model. Research into the pouch cell variant of this technology is also being carried out at the US Massachusetts Institute of Technology, Department of Materials Science and Engineering, (MIT) as part of the Advanced Battery Program. The chemistry of these cells is based on the use of lithium anodes, dry block copolymer electrolytes (BCE) and conventional Li-ion insertion metal oxide cathodes. The first generation of BCE comprised poly(oxyethylene methacrylate) (POEM) and poly(alkyl methacrylate) units doped with high concentrations of a lithium salt such as LiCF3SO3. MIT is also developing a second generation of polymer electrolytes based on graft co-polymer electrolytes where free radical synthesis is used to graft poly(dimethyl siloxane) on to the POEM backbone units. This results in a polymer with a wide electrochemical window with the added benefit of high thermal stability so that heating up to 300 ºC is possible without thermal degradation. Most of this MIT development is being funded by the US Navy’s Office of Naval Research. Avestor is reported to be developing a larger model weighing 175 kg which provides 42 kW and which has an energy rating of 21 kWh. Avestor is aiming to achieve between 120 and 200 Wh/kg with its designs whereas the MIT pouch design has been reported to have achieved up to 400 Wh/kg and 650 W/kg with a lithium metal anode and a lithium-cobalt oxide cathode. Up until now the use of lithium ion batteries has been confined to electronics applications which are physically relatively small. However, in a newly established joint venture between US car battery manufacturer Johnson Controls (51%) and French industrial battery manufacturer Saft (49%), the two companies aim jointly to develop a lithium ion battery for use in hybrid electric cars such as the Toyota Prius. The models envisaged could weigh up to 35 kg with a working voltage of 300 V. Development will involve the solution of some difficult scaling up problems from current designs and a target date of 2010 has been mentioned. In the meantime the joint venture will work on nickel metal hydride design which is currently used in hybrid cars.

28

Review of Materials and Properties

3.5.2 Capacitors Capacitors are available in a wide variety of shapes, sizes and chemical composition and have had to fall into line with the higher assembly temperature requirements arising from the move to lead-free solders. Speciality polymers are used in solid aluminium electrolytic capacitors whose characteristics include the ability to provide high microfarad capacitance in relatively small packages. Furthermore they are polarised with + and – terminals. As there is a risk of them exploding at the end of their service life a pressure relief vent is built into the capacitor casing. Polypropylene film appears to be replacing polycarbonate film as the material of choice for the manufacture of capacitors using wound film construction. These types do not have a preferred polarity and can withstand higher levels of surge voltage. The end of the service life of a film capacitor is marked by a decrease in its capacitance although it will continue to function. This is because the capacitor acts in a similar manner to a battery. It ages during use, suffering a decline in capacitance, finally falling to 5%, or even 2%, of its nominal value at the end of its working life. The self-healing function results from the polymer dielectric, which separates the electrodes, being able to surround holes created in the electrodes by power spikes. This maintains the insulation and helps to prevent short circuits thus prolonging the life of the capacitor. Capacitor performance deteriorates with time as the number of holes increases. Polyester films are confined to low voltages typically from 75 V DC to 400 V DC whereas polypropylene with higher crystallinity extends the upper working temperature to 120 ºC. Versions are available without impregnation or impregnated with rapeseed oil. The polypropylene types have a higher working voltage with some models able to handle 2 kV. Polyester film may or may not be metallised. Metallised polyester designs, which are suitable for both high and low impedance circuits, tend to be the smallest and most economical of the metallised polymer types. This design family combines the reliability of self-healing action with high dielectric strength and insulation resistance of polyester film. Designs are available which comply with thermal shock, vibration and moisture resistance specifications. Mylar polyester film is a product of the 50%/50% DuPont Teijin Films joint venture, dating from 1999, between DuPont and Teijin Limited. DuPont Teijin claims to be the world’s leading supplier of PET and PEN polyester films and also supplies Melinex polyester film. Toray’s joint venture in China is designed to produce PETP film for ultrathin capacitors. Applications are primarily for use in DC circuits such as blocking, coupling, decoupling, bypass and DC line filtering where the radio frequency (RF) and audio components are small in comparison with the DC rating. They have also been used successfully in such AC power applications as power factor correction and AC line filtering. They may be operated at all temperatures from –40 ºC to +85 ºC with derating to 50% at 125 ºC. They are intended for use in sealed encapsulated assemblies. Panasonic offers both polyester and metallised polyester film capacitors. The non-inductive, high stability, epoxy coated polyester types are also claimed to offer high volumetric efficiency and low losses. Additionally the metallised polyester film types are claimed to be self-healing. Their structure is composed of a number of discrete units to confine and isolate any dielectric breakdown. Panasonic also supplies miniaturised versions whose height and length dimensions are less than 8 mm with a corresponding thickness less than 5 mm.

29

Polymers in Electronics

Panasonic has responded to the demand for capacitors with higher operating temperatures by introducing a range of surface mounted electrolytic types. The polymer aluminium capacitors are rated between 2 V and 8 V and extend from 33 μF to 560 μF whereas the aluminium electrolytic types have a range of 1 μF to 1500 μF in the voltage band 6.3 to 35 V. Epcos offers epoxy resin sealed metallised polyester (polyethylene terephthlate) film types with the addition of a UL 94 V0 plastic case. Metallised polypropylene types offered by Epcos are claimed to have very good self-healing properties and a very high pulse strength. Rubycon’s PC-CON solid aluminium conductive polymer capacitors are available in ratings from 10 μF to 470 μF in the voltage range 2 V to 6.3 V and with an operating temperature range of –55 ºC to 105 ºC. These high performance, low equivalent series resistance (ESR) components measure 7.3 mm x 4.3 mm with a low height version which is only 1.5 mm high. Better performing low ESR polymer aluminium capacitors were reported to have been selected by a manufacturer of automotive braking systems because of their surface mount capability, lower board area space requirement and increased mechanical reliability. The specialist capacitor manufacturer ICW recently introduced a DC filtering 100 μF, 1100 V rated capacitor using a special segmented metallised polypropylene film somewhat smaller than its competitors but with enhanced working life, competitive pricing and delivery of under four weeks. Medium power designs are available for printed circuit board and also rigid mechanical mounting with voltage ratings from 75 V DC to 3 kV DC, high power designs extend from 1.4 kV DC to 2 kV DC. According to type classification the medium power capacitor case may be plastic or aluminium and be filled with a thermosetting resin. High power designs may be packaged in rectangular stainless steel cases with brackets. The range of medium power non-impregnated metallised polypropylene or polyester dielectric film capacitors from AVX extends from 12 μF to 400 μF at rated voltages of between 300 V DC and 1900 V DC. They have a controlled self-healing capability specially designed to provide a very high dielectric strength when working at temperatures of up to 105 ºC. Furthermore, their inductance can be as low as 18 nH and they will also withstand high surge voltage levels and high root mean square (RMS) current ratings. Applications include power supplies, motors and drives, induction heating and military use. These designs are preferred to electrolytic types because of their longer life, high RMS current ratings and superior tolerance of surge voltages. Traditional tantalum capacitors use a manganese dioxide cathode plate but some designs including Kemet’s KO-CAP surface mount polymer tantalum series have an organic conductive polymer cathode with a very low ESR and the ability to tolerate 125 ºC. Polymer tantalum versions retain their capacitance better at high frequencies. One reason is that the resistivity of manganese dioxide is at least 160,000 times that of tantalum. They also feature a benign failure mode which claims to eliminate the ignition failures which can occur in standard manganese dioxide cathode plate types. This is because organic polymers do not give up their oxygen if the capacitor experiences a short circuit failure. Operating at up to 80% of rated voltage these designs are claimed to be more reliable than standard designs operating at 50% of rated voltage.

30

Review of Materials and Properties

Furthermore, the use of conductive polymers delivers the desired capacitor self-healing properties without the undesirable ignition failure mode. The two main self-healing theories are that localised heating leads to the evaporation of the polymer at that point leading to a breakdown in the connection there. The second theory put forward is that polymer absorbs oxygen and creates a high resistance at that point as would be the case with a manganese dioxide cathode. The manufacturing process involves the polymer thickness build-up by repeated dipping and drying. Internal stresses are less in conductive polymer types because the polymer is elastic whereas manganese cathodes are hard and crystalline. Henkel offers its Hysol KO1052 rapid cure, silver-filled epoxy-based conductive adhesive to bond the cathodes in the construction of surface mount tantalum capacitors. This adhesive is suitable for in-line curing in as little as 20 seconds at elevated temperatures (200 ºC). Features of this adhesive include a low volatile content, reduced voiding, low electrical resistance and high peel strength. Tantalum supply problems have stimulated the search for alternatives, one of which is the closely related element, niobium which, in contrast, is abundant and inexpensive. Epcos claimed to be the first manufacturer to launch capacitors using niobium but others including AVX have entered the market. Capacitor manufacturing techniques are different because niobium oxide is a typical ceramic, being hard and brittle, whereas the metal tantalum is relatively soft and malleable. However, whereas tantalum polymer designs incorporate polymers as active ingredients, the plastics content of niobium designs is confined to their resin encapsulation. In 2005, AVX claimed that its TCJ tantalum polymer capacitors were the only lead-free ones available on the market which complied with the triple reflow requirement at 260 ºC. The range includes a low profile 1.2 mm T case style with a 47 μF model rated at 6.3 V with an ESR of 80 milliohms. AVX claimed to be the only company to have improved polymer performance to meet the stressful leadfree reflow 260 ºC temperature requirement which requires three reflow passes. AVX also claims that these products meet the IPC/JEDEC-J-STD-020c stringent performance. The TCJ capacitor family is also guaranteed to operate at up to 125 ºC with a defined post reflow soldering ESR. The family also has better capacitance retention and safer non-ignition failure when set against conventional manganese dioxide electrode capacitors. In applications where really high temperatures of up to 200 ºC may be encountered, Cornell Dubilier offers mica and Teflon (PTFE) electrolyte metal clad versions in silver-plated metal cases. These designs, which feature ultra-low inductance terminations and heat spreading when operating at high power, assure low ESR (Equivalent Series Resistance) to greater than 1 GHz, and high ripple current capabilities with stability in subminiature sizes. Equipment designers have decided that it is sometimes preferable to use components with higher specifications than those strictly necessary for a particular application because they offer better reliability and lower rework costs, a significant factor if their additional cost is far less than reworking. For example, a capacitor rated at 105 ºC may be a better buy than a standard unit rated at 85 ºC.

3.5.3 Coil Formers Coil formers, which carry windings in inductors, motors and transformers, must be tough and able to withstand the temperatures experienced. Polymers used include Vectra LCP, PBT, PC, PA and phenolic resins.

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Polymers in Electronics

3.5.4 Connectors According to Reed Electronics Research [4], the West European connector market was valued at €5 billion in 2004, rising by 1% in 2005. In geographical terms, Germany (35.1%) was the largest market, followed by France (14.8%) and the UK (12.4%). In application terms the automotive sector took the largest share (34%), followed by industrial and others (20%) and computers and peripherals (18%). It is impossible to generalise on the choice of polymers used by connector manufacturers since each company has a different set of criteria to meet. Typically choices are PA66, PC and PPS or, where manufacturer specific brands are concerned, Noryl and Vectra. However, the implementation of RoHS legislation has had a major impact on the connector industry where polymers now have to withstand the thermal stress of higher soldering temperatures of lead-free solder. DuPont Engineering Polymers contribution is a new LX series of Zytel HTN high performance polyamides. The operating temperatures of the new solders are around 250 ºC to 260 ºC which is some 20 ºC to 30 ºC hotter than traditional lead-based solder. LX glass-reinforced, flame-retardant grades are available with glass fibre contents of 20%, 30% and 40%. The new grades are tougher than their predecessors and users find that parts and assembled circuits suffer less damage during shipping, handling and service than was the case with earlier polyamide formulations. DSM also offers high temperature polyamides for this application and the American Bel Stewart Connector is using Stanyl TE250F6, with a HDT of 290 ºC in its MagJacks connectors whose applications include games consoles, modems and printers. Other DSM customers include Tyco Amp Den Bosch who moved from using LCP to Stanyl 46HF 5040 to mould PCMCIA (PC card) headers on the grounds of overall cost savings, better mechanical properties and very low warpage. LCP is still promoted for use in connectors and the recent introduction of Zenite 6130LX by DuPont Engineering Polymers is said to improve the strength and precision of electronic connectors. The card headers must securely hold 68 pins with a 0.6 mm pitch and withstand the often rough card insertion practices of laptop computer owners. Furthermore, Stanyl’s heat resistance is compatible with laptop main board production processes where surface mount components have to be attached using lead-free solder. The Stanyl range of grades includes high-flow, abrasion resistant and unfilled (non-reinforced) options. Permissible fillers include glass fibres, minerals lubricants, impact modifiers or flame retardants. In December, 2005 DSM launched its Super Flow Stanyl grade with the 30% glass fibre reinforced 46SF5030 formulation whose potential applications include thin walled connectors, with walls down to 0.1 mm thick, and the smallest types of connectors, including flexible printed circuit (FPC), flat flex cable (FFC) and subscriber identity module (SIM) card types, where pitch values well below 0.3 m are encountered. Such applications require this material’s superior flow ease of processing and exceptional strength and ductility. Edge connectors for PCB are typically injection moulded using LCP, polybutylene terephthalate (PBT) or PA. The connector manufacturer Meritec, opted for Vectra L130 LCP from Ticona to mould a compression edge card connector which has the required flatness, rigidity and dimensional stability needed for a money changer system application. The connector itself is 10.7 cm long with a housing wall thickness of between 0.635 mm and 0.762 mm. The commonly used D-subminiature connectors are available in 9, 15, 25 and 37 way versions with each pin typically having a 1 A current carrying capability and a dielectric withstand voltage of

32

Review of Materials and Properties

1000 V for one minute. Maximum contact resistance is 25 milliohms with an insulation resistance of one thousand mega-ohms. Insert material options include UL 94-V0 glass-filled polyester, PBT and Nylon 6T. Tyco Electronics uses DuPont flame retardant polycyclohexylene dimethyl terephthalate (PCT) in the manufacture of its connectors and interconnection devices, notably for automotive and other industrial applications. Another connector material composition used by Tyco for connectors which are mounted in the car engine compartment, or behind the dashboard, is Thermx CG023 which contains 20% glass fibre reinforcement. This formulation features dimensional stability, low warpage, stiffness, toughness plus the high temperature performance needed for lead-free soldering. This material, which also possesses improved hydrolysis resistance, is claimed to be superior to PBT for these applications and is also claimed to be less expensive than many well-known high performance plastics. In the case of connectors for white goods, domestic appliances and IT applications Tyco is reported to be using DuPont Thermx CG923 which combines the properties of the CG023 composition with a UL 94 V0 classification. Tyco Electronics is now promoting its ranges of PARA-OPTIX and MPO fibre optic cable connectors. These connectors allow either 12, 24 or up to 72 individual fibre optic connectors with a single compact interface. Hi-Rose has selected PPS and chloroprene rubber for its new LF range of waterproof connectors. PPS possesses ease of flow which enables delicate but extremely stiff components to be produced. A wide range of polymers is used in electrical connectors including high temperature glass-filled thermoplastics which provide good insulation. The criteria used by a leading connector manufacturer for polymer selection include: •

Dielectric strength.

•

Comparative tracking index.

•

Surface and volume resistivity.

•

Continuous service temperature.

•

Water absorption.

•

Radiation resistance.

•

Flammability rating.

•

Resistance to hydrocarbons.

Flammability ratings for plastics are defined in the American Underwriter’s Laboratory UL 94 regulations which determined laboratory horizontal and vertical tests with a naked flame. The sequence of classification ratings HB, V2, V1, V0 and 5V represents steadily increasing flame retardant behaviour. In a joint venture, DuPont-Toray, Ichimura Sangyo and Takayasu have announced the development of a new manufacturing process for flame retardant resins which avoids the need for such additives as organic phosphorus flame retardants. Instead the flame retardant properties are obtained by adding

33

Polymers in Electronics

uniformly and highly dispersed flame-retardant Kevlar para-aramid fibres to the resin matrix. The resulting resin compounds have low specific gravity compared with conventional glass reinforced plastic flame retardant compounds and anistropy is also small. These new compounds have high anti-wear properties with three times the tracking resistance of conventional compounds. High voltage components, notably circuit breakers and connectors, are seen as the main applications for this new technology. Adhesives used in connector applications include Loctite’s 3887 isotropic epoxy conductive grade. This two part product comes as a thick paste which is cured by exposure to heat and which is designed for enhanced adhesion to gold plated devices in electronic interconnect applications. The product formulation is reported to absorb stress associated with extreme thermal mismatch between dissimilar substrates. The end-use of the connector has a strong influence on polymer selection. Nowhere is this more evident than in the case of the use by American connector manufacturer Greene Tweed & Co., of Victrex PEEK-HT high temperature polymer as the basis of its Arlon 2000 compound for its 8-pin Seal Connect connector mouldings. These have been specially developed for use in oilfield exploration and production. The connectors are designed to withstand prolonged exposure to an applied pressure of 138 MPa at 204 ºC, and a short-term exposure to pressures of 172 MPa at 260 ºC is also reported to be possible. The high-performance thermoplastic is considered to be the ideal material to overmould conductive pins to create a void free connector thereby completely isolating the conductor. Furthermore the material has good mechanical strength and very consistent properties throughout its operating temperature range. It also fulfils another critical requirement of this application, its ability to operate within a very tight space. Another arduous application is for circular connector accessories which comply with the bending moment, shock, thread strength and vibration requirements of the Mil-C-38999 and Mil-C-85049 standards. Manufacturer Glenair selected Ultem 2300 PEI from GE because of its superior corrosion resistance to metals of equivalent strength. In fact Ultem 2300 weighs 80% less than its stainless steel and 40% less than its aluminium equivalents for these parts. Swiss cylindrical connectors are usually supplied with metal bodies although medical and military users favour high specification plastic bodied versions, there is also a strong demand for low cost plastic models. However, according to one leading manufacturer, there is no evidence of long standing users of metal-cased models moving over to plastic-cased versions. The Swiss company, WW Fischer, offers PTFE (Teflon PTFE or Hostaflon), PBT (Celanex, Crastin, Ultradur or Valox) or PEEK (Victrex) insulator material options in its 405 series of cylindrical connectors according to the requirements of working temperature and other criteria. PEEK is an expensive polymer which tends to be employed when other materials fail to meet the specification requirements of the application. Other Fischer connector types use polyamide-imide (Torlon) or POM (Celcon, Delrin or Hostaform). Elastomeric seals used by Fischer in conjunction with their connectors are made from acrylonitrile-butadiene rubber (NBR; N BUNA) or to MIL-P-25732, fluoroelastomer (FPM; VITON), polychloroprene elastomer (CR; Neoprene), ethylene-propylene diene elastomer (EPDM) and styrene-ethylene-butadiene-styrene thermoplastic elastomer (TPE-S or TPE-O) where each compound is followed by its trade name. Fischer’s Swiss competitor, Lemo, manufactures a similar range of connectors including the Redel types which have a plastic body.

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Review of Materials and Properties

The connector range of the German manufacturer, Harting, consists mainly of rectangular types where the preferred insulating material for the connector inserts and hoods is PC with PA being selected for the locking elements. In some models PA is also elected for the inserts. However, for high voltage models designed to operate at 5 kV, the insert material is polycarbonate/PTFE. The need to use lead-free solder in surface mount technology applications where soldering temperatures of between 220 ºC and 240 ºC are likely to be encountered has necessitated the use of such high temperature polyamides as DuPont’s Zytel HTN LX resins for board assembly. It is interesting to note that some Japanese companies have been using lead-free solders in their flow soldering processes since 1997.

3.5.5 Membrane Keypads These are typically built on a polyester base membrane (PETP, 35 μm, copper-laminated) with a polyester spacer membrane, safety chamber and front membrane. The snap disc being gold plated stainless steel. Other designs use electrical contacts made from silver, silver on carbon or carbon only. Keypads may also be made from conductive silicone rubber. Conventional computer keyboards made from ABS, polyester or other polymers, may be covered by a polymer overlay to protect it against dirt, dust, water or other substance present in a hostile environment. Polyester and PVC overlays are used in a wide variety of applications with computer and instrumentation equipment in dental and medical healthcare and other areas. Typical casing materials include PC and polychloroprene. Membrane keypads face significant competition from new technologies now being developed. For example, research at the University of Pennsylvania and Yamanashi University, by Hohnholz, Okuzaki and MacDiarmid [5], involves the fabrication of a polymer-dispersed liquid crystal display using electrodes of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrene sulfonate) in conjunction with a push-button keyboard array. The display is produced by the design and printing of a line pattern on a substrate which is then coated with a conductive polymer solution. Subsequently the reverse-printed toner pattern is removed. In another development researchers at Fujitsu Laboratories and Fujitsu Component have succeeded in developing conductive polymer touch panels where the manufacturing process involves the layering of a low resistance conductive polymer on to a plastic film. Proposed applications include touch panels for computers and mobile phones. Extreme operating conditions call for heavy duty materials, a case in point being the membrane switch material required for the ocean going yacht made by Tiara for which Autotype’s Autotex XE (Extreme Environment) hard coated polyester film was used. Unlike traditional substrate materials Autotex XE can withstand high light levels, 85 ºC operating temperatures and humidity levels of 85% relative humidity. Conventional films might delaminate, become brittle or flake under extreme conditions. Autotex XE film is polyester-based with specially constructed hardcoat and primer layers.

3.5.6 Plugs and Sockets Polymers used to insulate plugs and sockets include PA and TPE. However, for plugs moulded on to cables the universal polymer choice for plug bodies has been PVC which can tolerate temperatures up to 60 ºC.

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Polymers in Electronics

Domestic mains sockets are moulded from tough materials designed to withstand abuse during the installation process. Polymers used include PBT which may be used, with glass fibre reinforcement, in the manufacture of lamp sockets where its resistance to discoloration and heat are valuable qualities. In applications where higher temperatures are likely to be encountered, flame retardant PET may be used. Polyester and glass fibre reinforced polyester bodies are a popular choice for industrial plugs and sockets especially those destined to be used in hazardous environments where ATEX (from the French ‘ATmospheres EXplosible’) directives apply. The relevant Directive 100a ATEX Directive (94/9/EC) was issued by the European Commission in 1994 and became law on July 1st 2003. It is important to note that no guarantee of safety or protection will exist if the plug and its mating socket are sourced from different manufacturers. Furthermore, any on-site product will invalidate the certification. The ATEX classification of hazardous environments is as follows: •

Zone 0 is where an explosive mixture of gas, vapour or dust is always present.

•

Zone 1 is where an explosive mixture of gas, vapour or dust is likely to occur during normal operation.

•

Zone 3 is where an explosive mixture of gas vapour or dust is not likely to occur during normal operation and, if it occurs, it will only exist for a short time as in the case of a leak.

•

Zone 21 is when a cloud or layer of combustible dust is present.

•

Zone 22 is when a cloud or layer of combustible dust is present for short periods.

3.5.7 Printed Circuit Boards (PCB) In general purpose applications competitively priced thermosets are used for the printed circuit board base material which is usually ‘FR4 (Flame Retardant)’. One of the main flame retardants used in America is to have tetrabromobisphenol-A reacted into the epoxy resin. Non-halogen systems include additives such as alumina trihydrate, alumina trihydrate/red phosphorus and aromatic phosphates. Flame retardant epoxy coatings are reported to use ammonium polyphosphate with char-forming additives. The term prepreg is used for the non-conducting semi-cured layers of FR4 which are used to separate the conducting layers of a multiplayer printed circuit board. Printed circuit broad laminates comprise a layer of prepreg bonded between sheets of copper foil. The Japanese NEC company is understood to be marketing a self-extinguishing reinforced glass-epoxy resin for PCB. Cookson’s Polyclad Laminates subsidiary, one of the world’s leading manufacturers of a full product spectrum of laminate and prepreg materials was recently acquired by the American Isola Group SARL for US$91 million (£51 million). Isola is ultimately owned by the private equity Texas Pacific Group and Redfern Partners in the USA. Multilayer PCB may be reinforced with glass fibre fabric. E-glass is available from the Dielectric Solutions company which has developed an ultra lightweight glass fibre fabric. Its use is claimed to result in a better performing product which is typically thinner and stronger than the competition and which has improved electrical, thermal and other properties.

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Review of Materials and Properties

One of the critical properties when selecting PCB laminate materials is their Tg which become increasingly important in the event of a move to the use of lead-free solders with their higher melting points than traditional lead-based formulations. High temperature FR4 material has a Tg of 150 ºC, continuous operating temperature of 130 ºC, and will also withstand temperatures of between 260 ºC and 280 ºC for brief periods. However, the use of polyimides will permit continuous operation at elevated temperatures. Other important values are the thermal decomposition temperature (Td), and T260, for example, where T260 is the time at 260 ºC before decomposition occurs. Specialist materials include buried capacitance laminate for wireless communication interconnects, servers and measuring instrument applications. This is a 0.002 inch thick glass reinforced material with double treated copper foil on both sides. The key features of this product are claimed to be improved electrical performance, excellent dielectric thickness accuracy and excellent electrical integrity. In selecting suitable PCB material it is necessary to bear in mind that it will usually have to withstand at least three exposures to high temperature during the solder reflow process. One to each side of the board and a third after post test rework. Another potential problem with substandard laminated boards is that the laminations may separate when exposed to high temperatures. The American ThermalWorks company has developed a new carbon fibre composite printed circuit board and substrate material, STABLCOR, which comprises a high temperature resin incorporating carbon fibre sandwiched between two very thin layers of copper. The material has a Tg of 170 ºC. However, the company is developing a version with a Tg of 240 ºC. The material is designed as a ‘plane’, or non-signal carrying layer in a ply stack with other dielectric layers to make a composite PCB or device substrate. The carbon composite material has a dielectric constant of approximately 13.4 which makes it electrically conductive. This material allows the user to tailor the coefficient of thermal expansion of a PCB down to 3 ppm/°C to match that of silicon. The Japanese Daicel Chemical company claims to have produced the next generation of photoresist polymers which are used in the manufacture of PCB with an extremely fine line width of 0.1 μm. The production process involves the use of its in-house developed catalyst in conjunction with Nhydroxyphthalimide. Lower cost flexible printed circuits use polyester base materials with more expensive polyimide, including DuPont’s Kapton and Toray’s Metaloyal, selected for applications where higher performance is required. Metaloyal is an electrolytically plated two layer flexible substrate film with a 2-18 μm copper layer formed on the surface of the polyimide film by electrolytic plating. Toray claims that superior fine pitch etching capabilities coupled with good flexibility and heat resistance result from the copper plated layer and the high adhesion of base film. An interesting new product from Japan’s Kyocera Chemical Corporation is a flexible fibre-reinforced plastic circuit board which is manufactured from a non-woven cloth of glass fibres impregnated with epoxy resin and sandwiched between layers of copper foil. Developments of low cost flexible printed circuit manufacturing techniques have involved a combination of self-assembled polyelectrolyte, ink-jet printing of a catalyst and electroless plating of metals on a flexible substrate at low temperature. This work has been carried out at Taiwan’s Industrial Technology Research Institute and the University of California and was described by Cheng, Yang, Chiu, Huang, Chang, Ying and Yang [6]. Flexible and hybrid flex rigid printed circuits are growing

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Polymers in Electronics

in popularity and may be produced on a low cost polyester PET dielectric substrate using polymer thick film (PTF) technology whose exponent, the US Parlex Corporation, claims world leadership of the flexible interconnect product sector. The manufacturing process involves high speed screen printing of thick film conductive inks. Parlex can produce PTF circuits having up to four layers of circuitry with integrated membrane and tactile switches. The circuits may also incorporate surface mount and through-hole assembly techniques using lead-free adhesives in order to comply with RoHS directives. Adhesive options are silver loaded Poly-Solder, a patented isotropic conductive adhesive, or Parlex’s own proprietary Z-Axis adhesive (anisotropic conductive adhesive). The benefits of PTF circuitry include lower cost when compared to conventional copper-based circuits on a polyimide substrate. The circuit components are also said to be more reliable because the curing temperature of the adhesives is far lower than the temperatures now being experienced by traditional PCB in solder reflow processes. Whereas traditional PCB are flat or flexible, injection moulded three-dimensional versions, also known as moulded interconnect devices (MID) have been developed which combine a circuit board, enclosure, connector and cable into one unit. Traditional techniques of installing the electronic circuitry on to the MID have included laser imaging, two-component moulding or hot foil stamping. In Germany the selection of a suitable base polymer for the laser direct structuring (LDS) process developed by LPKF (Garbsen, Germany) resulted from a government supported project which also involved BASF. The process was presented by Reinhard Stransky of BASF at a trade press conference at Ludwigshafen on June 22nd 2004 in connection with K2004. On June 24th 2004, LPKF and BASF signed a know-how and licence agreement covering the production of three-dimensional electronic circuits (3D-MID) using the LDS process. The process uses Ultramid T (a crystalline, semi-aromatic Nylon 6/6T), a special BASF compound which incorporates 30% glass fibre and other properties to facilitate the initiation of metal deposition and metal adhesion. The final result, after incorporating a special laser-sensitive metal complex, was Ultramid T KR4380 LS. This polymer has the high melting point of 295 ºC and is equally suitable for automotive and industrial applications. The three-stage MID manufacturing process comprises conventional injection moulding, laser structuring and electroless plating. The second stage uses a laser to inscribe the required circuit on to the Ultramid T KR4380 LS moulded part. Exposing the part to 1064 nm wavelength infra red laser light breaks the compound’s metal complex down to its elementary metal component and its residual organic groups. The laser treatment leaves behind a roughened surface containing embedded metal particles to which metal conductors can adhere. These particles act as nuclei for subsequent crystal growth during the third stage metallisation process which goes on to produce a continuous layer of metal, usually copper.

3.5.8 Relays In the selection of plastics materials, invariably compliant with UL 94 V0, for use in relays, low degassing properties are required. This is necessary because some polymers are inherently hygroscopic and so must be dried thoroughly before use. Other polymers may absorb gases during

38

Review of Materials and Properties

the manufacturing process and these may be subsequently released by the mouldings used as actuating combs, base plates, coil elements and housings of the finished sealed relays. The sealing prevents the ingress of polluting gases from the environment. However, the long-term reliability of the relay would be affected if moisture, for example, were to be released by the plastic components and corrode the relay contacts. The Berlin technical centre of Tyco Electronics has developed an especially silent relay with a completely redesigned electromechanical system. The minimal noise it emits is attenuated to an inaudible level by a protective housing made from a specially developed blend of DuPont’s Crastin polybutylene terephthalate (PBT). As in other similar devices the device is encapsulated in a thermoset resin.

3.5.9 Resistors The main polymer use in chip resistors relates to the encapsulation material which is frequently PA but may be Novolac epoxy or epoxy resin. Silicone rubber encapsulation, which provides a cushioning layer which isolates the resistive element from external stresses, and polymerised moisture protection layers are two other uses of polymers in resistors. Encapsulated resistor capacitor networks utilise epoxy/anhydride conformal body material. Conformal implies a coating of uniform thickness as would be obtained by a dipping process, for example. Small wirewound resistors are made by winding the resistance wire round a proprietary bobbin and then encapsulating it in silicone rubber over which an epoxy shell is moulded. Other resistor formats use foil elements with Kapton/adhesive insulation coated with epoxy enamel. Plastic potentiomers described as robust yet economical use a conductive polymer as the resistive element of the design. The polymer used is effectively a thick screen-printed film ink similar to the cermet (ceramic/metal) compounds which are also used in variable resistors. Conductive polymers are superior to cermet in terms of their dynamic noise characteristic but have inferior moisture resistance, temperature coefficients, power dissipation and wiper current capacities. The temperature coefficient and power handling capabilities of wirewound resistors are higher. The cost of conductive polymers is low and they offer minimal contact resistance variation coupled with a long rotational life with Compodis claiming a service life of two million shaft revolutions for its R22P range. There is virtually no friction or wear on account of the polymer’s smooth surface. The R22P range of resistance values extends from 1 kilo ohm to 50 kilo ohms with an end stop which limits travel to 340 degrees. In this context it is interesting to note that Henkel’s Hysol’s KE4239 conductive coating, used in conjunction with its HD3487 hardener, produces a solvent-based epoxy system which has low volume resistivity and good adhesion plus the ability to develop a tough film. For these reasons the material can be used to rebuild areas worn away by sliding contacts. It may also be used as a conductive base film for electroplating where a reliable bond is necessary. Other applications include employment as a sprayable RFI shield. The shaft of a variable resistor will often be made from a thermoplastic polymer whilst the mounting bush may be glass-filled Nylon or a diecast zinc alloy.

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Polymers in Electronics

Polymer-based positive temperature coefficient (PTC) resettable devices, from Bourns, Littelfuse and other suppliers, may be coated in a flame retardant epoxy polymer insulating material, which meets UL 94 V-0, and then cured. PTC devices act as circuit protectors because, provided the current flowing through the device is lower than its specified level, the resistance of the device will be negligible and no self heating will occur. In a fault condition the current will exceed the specified value, self heating of the device will occur, its electrical resistance will rise and therefore reduce the current flowing through the circuit thus protecting other circuit components. PTC devices are available in a range of specifications to meet defined requirements in low voltage electronic circuits where they may, for example, protect automotive electronic circuits, cellular phones, laptop computers, loud speakers, power transformers, rechargeable battery packs, security and fire alarm systems and other products. Tyco Electronics’ Raychem subsidiary offers the PolySwitch range of resettable circuit protection devices which are polymeric positive temperature coefficient devices. They act in a similar way to thermistors by limiting the flow of dangerously high currents during fault conditions. Subsequently, when the fault is cleared, and the power to the circuit is removed, they automatically reset. The product range includes resettable fuses, 5 mm wide or less, which operate as low resistance, series elements between battery cells and circuitry. These are particularly useful when used in conjunction with lithium ion batteries where an accidental short circuit in the load could have serious consequences. If this happens with the fuse in place the electrical resistance of the fuse will increase rapidly thus reducing the current flowing in the circuit.

3.5.10 RFI Screening Controllers and other small electronic devices may be RFI, also EMC screened if required, by enclosing them in a suitable metal loaded plastic, typically ABS. In the frequency range 100 to 1000 MHz such enclosures can provide attenuation levels in excess of 50 dB.

3.5.11 Sensors In a typical application the Siemens SIMAF SP/1 automotive mass air flow sensor comprises a transducer and an electrical connector which are moulded separately then joined together afterwards. Design flexibility allows different types of connector to be used in accordance with the customer’s requirements. For this particular application Siemens VDO Automotive AG used two different grades of BASF Ultradur PBT. Sensors also enable equipment operating conditions to be measured and monitored. Some types of thermocouples to measure temperature are inherently fragile and may be mounted on a temporary PA film carrier, which is tough, flexible and dimensionally stable with a continuous rating of 230 ºC, peeled off prior to installation. Other models are constructed on an insulated PA carrier. Housings may be made from glass-filled PA, PBT, PC, thermoplastic polyester or ABS. Temperature sensors are non-invasive and can be attached to either flat or curved surfaces. Platinum resistance temperature detectors may be used to measure the temperature of items with a low mass

40

Review of Materials and Properties

where it is important that the sensor itself does not affect the temperature being measured. The temperature ratings of some sensors mean that their leads must be insulated with high performance polymers, typically Kapton and Teflon. These polymers may also provide moisture resistance for condensation and shallow immersion. Teflon is also used to produce protective flanges and films for the sensor materials in environments where the caustic or corrosive chemicals present would destroy traditional sensors. Polymers may form an important part of the component’s packaging as is the case with butt bonded thermocouples where the free filament is supported on a temporary polyimide film carrier which can be peeled off, or partly cut away, prior to attachment to the surface whose temperature is being monitored. The carrier is tough, dimensionally stable and able to withstand a continuous operating temperature of 260 ºC. The frame is coated with a thermoplastic adhesive film to facilitate surface attachment. The benefits of optical fibres include their immunity to EMI. Optical sensors and couplers are often encapsulated in PC housings. Electronic controllers and their associated sensors are to be found in areas where electromechanical controllers formerly held sway as in white goods, for example, washing machines. The logistics, manufacturing, retail and wholesale sectors are now waking up to the advantages of RFI systems which use detectors, similar in some respects to barcode readers, to monitor the movement through the system of tagged products. The data generated can be used to improve the management of the business in such areas as stock replenishment. Amongst the more unusual types of sensors is one called ElekTex from Eleksen (Iver Heath, UK). This washable sensor is made from 100% fabric and has three layers. The upper and lower layers are made from a conductive material, and the middle layer of the sandwich will only conduct electricity when pressure is applied. The sensor can be incorporated into garments where the change in apparent resistance is a function of the pressure applied to it. A possible application for the material is an emergency device to be incorporated into the uniform of the emergency services to be used to summon assistance in a similar way to a keypad on a mobile phone. The device would have a bluetooth connection to a mobile phone, for example.

3.5.12 Switches Typical materials for normal switches and fuseholders include Nylon 6.6, glass-filled PPA and PC where transparency is required. Heat-resisting and self-quenching (UL 94 V-0) materials include diallylphthalate and PSU. When installed outdoors, switches and sockets must withstand severe weather and other adverse environmental conditions. Growing public concern regarding sources of infection, especially in hospitals, has led to the incorporation of an antimicrobial additive in switch and socket mouldings. Polygiene from the Swedish Perstorp Compounds AB is claimed to be effective against MRSA and the severe acute respiratory syndrome (SARS) virus.

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Polymers in Electronics

3.5.13 Terminals Crimped terminals are a popular way to terminate cables. The choice of polymer for the terminals themselves will be governed by environmental circumstances. Normally PVC is used but high temperature applications will call for PA or PC insulators. For terminal strips PA6, conforming to UL 94 V-2, and self-extinguishing PA66, with or without glass reinforcement, are frequently used. Terminal blocks are made from glass-fibre reinforced PA, polyesters or polyethylene. Flame retardant PA66, conforming to UL 94 V-0 is a popular choice as is UL 94 V-0 flame retardant PA68, Lexan PC with an operating temperature range from –20 ºC to +125 ºC and a short-term temperature tolerance of 160 ºC.

3.5.14 Touch Screens Whilst the mouse is the preferred control option of many personal computer users, touch-screens are increasingly being used in industrial and other applications including hospital patient care systems, gaming machines and computer installations in post offices and restaurants. The various control technologies comprise resistive, surface wave, projected and surface capacitance and infra red. However, not all the systems invariably involve the use of polymers. Those which do include the resistive system whereby a clear acrylic, PC or glass substrate is attached to a second flexible polyester layer. Alternatively, two flexible layers may be mounted on a solid clear window. The surface of the clear substrate is coated with indium tin oxide (ITO) on to which a small electrical current is constantly applied. The ITO coating is also applied to the polyester overlay whose surface is covered by a pattern of hundreds of microscopic dots which keep the substrate and the overlay apart. Finger or other pressure on the outside of the overlay produces a local short circuit in such a way that the computer recognises the X and Y coordinates of the point of contact and acts accordingly. Capacitive versions use a charge transfer system which needs no electrical link between the touch of the activating finger and the detection circuitry. This is because the presence of the finger alters the circuit capacitance between two plates which in one example are printed patterns of (transparent) ITO on the reverse side of a PET sheet which is then bonded to the underside of the touch screen. Another rather more complex and less transparent option is to adopt a two layer structure where one set of plates is printed on each of two ITO layers. In opaque sensors, the least expensive option, the capacitor plates can be printed circuit patterns on a low cost PCB. The Projected Capacitative Technology system uses embedded ‘microfine’ wires in a multi-layer laminate behind a protective front surface. The advantages for this system include its negligible effect on light transmission through the screen and the fact that the touchscreen itself is impervious to accidental and malicious damage ranging from spilt liquid to grease dirt and scratches. The screen may also be used by a gloved finger. Furthermore, because it does not have a surface-active sensing array, it does not suffer from ‘drift’ necessitating recalibration. Infra-red technology operates by means of miniature light-emitting diodes (LED) which are mounted beneath the bezel which surrounds the computer screen. LED are housed in epoxy packages which may be water clear or tinted. LED offer significant advantages over incandescent lamps. Whilst they are more expensive, LED clusters will operate for around 100,000 hours before they have to

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Review of Materials and Properties

be replaced whereas incandescent lamps will need replacement after 1,000 hours. Furthermore, LED are also more reliable and use only 10% of the power of an incandescent lamp of comparable brightness. When compared with quartz halogen lamps, LED are at present more efficient and longer lasting but still have to achieve comparable brightness levels. Currently the attainable efficiency of white light LED is around 50 lumens per watt of power consumed but the industry is aiming for 100 lumens per watt by 2010. This figure is already reportedly being achieved by some manufacturers under laboratory conditions. LED are now available in a wider range of colours than in the past and Rohm, for example, offers high brightness surface mount and devices with LEDs in red, orange, yellow, green, blue and white versions. The global LED market is forecast to double from £2.1 billion in 2004 to £4.1 billion by 2009. Nichia of Japan is the market leader in the field of high brightness LED whose technology is fully patented. The pattern of LED in a touch screen application transmits infra-light beams, both from top to bottom and from side to side across the face of the screen to infra red light receivers located directly opposite. Touching the screen with a finger or stylus will break the beam at a point whose X and Y coordinates can be readily recognised by the computer. Alternative systems operate on the basis of acoustic, capacitive or laser technology. The Zytronic touch screen is capacitive with fine wires and poly vinyl butyral (PVB) or PU layers sandwiched between glass panels. Touching the screen affects its local capacitance. Applications include automated teller machines (ATM) for cash withdrawal.

References 1.

UL 746 B, Polymeric Materials – Long Term Property Evaluations, 2006.

2.

IEC 60216-1, Electrical Insulating Materials – Properties of Thermal Endurance – Part 1: Ageing Procedures and Evaluation of Test Results, 2001.

3.

UL 94, Tests for Flammability of Plastic Materials for Parts in Devices and Appliances, 2003.

4.

European Electronics Markets Forecast, Reed Electronics Research, Wantage, Oxfordshire, UK, 2005.

5.

D. Harnholz, H. Okazaki and A.G. MacDiarmud, Advanced Functional Materials, 2005, 15, 1, 51.

6.

K. Cheng, M-H. Yang, W.W.W. Chiu, C-Y. Huang, J. Chang, T-F. Ying and Y. Yang, Macromolecular Rapid Communications, 2005, 26, 4, 247.

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44

4

Overview of European Electronic Component Markets

4.1 Introduction The problems facing the industry can be neatly summed up by the statement by the President and Chief Executive Officer of Epcos in his company’s 2005 Annual Report and Accounts. He revealed that the prices of passive electronic components had declined significantly for the fourth successive year and that, as far as his company was concerned, prices for its products had fallen by almost €800 million since 2002 which represents an average annual price erosion of €200 million. The component manufacturers’ problems have been compounded by rising oil prices which have fed through into higher polymer prices. This problem has been highlighted in a recent survey by the British Plastics Federation (BPF) [1], reported in the February 10th 2006 issue of the Financial Times, which cited average October 2005 price rises of 58% for gas and 56% for electricity. Furthermore, polymer manufacturers have been imposing price increases due largely to the rise in the cost of oil. BPF members have been unable to pass the increased costs to their customer by raising selling prices. Consequently, it would appear that component manufacturers are trapped in a situation where their raw material costs are under pressure to rise whereas the market is driving sales prices down. This is clearly an untenable situation. However, some sectors of the market performed well in 2005, which was a good year for large infrastructure projects since they involve considerable investment in instrumentation which has a high electronics content. Other growth areas include medical electronics and the security sectors where there is a rising demand for electronic protection against terrorism. The recent proposal to install detection systems at railway stations throughout the UK is an example of this trend. The quantity of electronics hardware needed for the UK introduction of identity cards will also be considerable. Nevertheless, in many areas, manufacture and assembly in the UK is no longer economically viable and so companies continue to close their UK plants and move production to countries where labour costs are lower.

4.2 Market Analysis The European Electronic Component Manufacturers Association (EECA) claims to represent more than 95% of European electronic components production involving more than one thousand companies. The organisation comprises four autonomous industry associations with members drawn from the national trade associations of the member countries as well as from manufacturing and related industries. The associations are: •

European Semiconductor Industry Association (ESIA)

•

European Display Industry Association (EDIA)

•

European Packaging and Interconnection Association (EPIA)

•

European Passive Components Industry Association (EPCIA)

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Polymers in Electronics

In 2004, the EECA reported that the electronic components markets of the Europe, Japan and Americas regions each accounted for a relatively stable 19% share of the total world market. However, the Asia Pacific region comprising Australia, China, Malaysia, Singapore, South Korea and Thailand is not only the largest region, with a market share of 43%, but it is also taking market share from the other regions of the world. The world share of the Asia Pacific region constituent markets was estimated to have expanded by an aggregate figure of 3% in 2004. The European Union market for electronic components, according to the EECA, is dominated by three countries which collectively accounted for 61% of the total 2004 market which was stated by EECA to be €47.7 billion. Germany led, with a national market size of around €12.79 billion, followed by the UK with a market size of around €10.73 billion and France was reported to have a market size of €5.57 billion. In 2004 sales of passive components were €3.78 billion thus accounting for approximately 8% of the total European electronics components sales with the semiconductor sector’s sales of €31.7 billion representing a share of around 66.5%. The largest market in 2004 for electronic components in Europe analysed by application is the computing sector with a market size of €13.51 billion which represents a 29% share of the overall market. Communications, especially mobile phones, was the second largest market and amounted to €10.97 billion or 23% of the market. It was followed by automotive where the figure of €9.15 billion represented a 19% share. Consumer and industrial categories, with €6.5 billion and €6.2 billion, respectively, had shares of 14% and 13%. The customers for electronic components manufacturers can be categorised in four major ways, catalogue distributors, contract equipment manufacturers (CEM), original equipment manufacturers (OEM) and overseas distributors. In terms of consumer electronics, the American market, where US sales of these products exceeded $135 billion in 2005, may be seen as a pacemaker for trends on this side of the Atlantic. The average American household is reported to own 25 consumer electronics products ranging from digital cameras and mobile phones to large screen digital television sets. US sales of digital TV sets grew by 60% to $17 billion in 2005. In 2006 the US Consumer Electronics Association (CEA) has forecast a further rise in digital revenue to $23 billion representing total unit sales of 15.9 million with high definition (HD) TV models outselling analogue designs. In the UK, for example, 2005 sales of TV sets were reported to be 4.5 million units. The trend to large screen digital models is accelerating with Dixons, a major UK retailer (in the process of changing its high street identity to Currys.digital), announcing that it would no longer sell sets with cathode ray tubes (CRT) apart from a limited range of 14 inch sets which were said to be popular with students who are probably looking for low cost TV when moving away from home. All these products contain electronic components, many with a significant polymer content. The health of the components sector is dependent on the market for electronics products.

4.3 Mobile Communications One of the major businesses driving the market at the present time is mobile communications. Despite apparent market saturation in parts of Europe the number of mobile phone users worldwide was expected to exceed two billion before the end of 2005, a year in which sales grew by an estimated

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Overview of European Electronic Component Markets

21% with 795 million mobile handsets being shipped. This figure represents incredible year on year growth from the estimate of 280 million units in 1999. The number of mobile phone subscribers is expected to rise to three billion by the end of 2008. Today’s typical mobile phone handset, will have a plastics content of approximately 40% though this figure rises to 75% if the analysis is calculated on the basis of weight. Since 1992 the average weight of a mobile phone is said to have fallen 500 g to today’s figure of 100 g. A veritable cocktail of polymers is used to make a mobile phone with ABS or PC being used for the outer case because of their weight reducing qualities and their durability. Good transparency is imperative for the screen for which PC or PMMA may be chosen. Connector manufacturers have several options with PBT and PA providing stability. For safety reasons elastomers provide the raw material for antennas. PCB base material is invariably an epoxy resin because it offers heat resistance and design flexibility. The components themselves may be made using PA, PBT and PES which deliver a superior performance in terms of insulation and heat resistance. The pace of change is now so fast that new developments coming out of university laboratories are being commercially exploited within a few years. For example, mobile phones can now be made from self-repairing composite polymers. The ability to self-repair is obtained by the dispersal, within the polymer, of micro-encapsulated bonding resins and catalytic chemical triggers. The repair process is activated if cracks develop and the capsules are ruptured. The resin is then released to be polymerised in the presence of the catalyst thus ‘healing’ the crack. Research has been reported to reveal that the material retains around 75% of its original toughness when ‘healed’ in this way. Around half of current first time mobile phone users are to be found in China, India, Brazil and Russia. Thus, manufacturers see plenty of scope for further sales in these countries in particular. The average price of handsets continues to fall with Nokia, whose world market share is around 33%, reporting an average unit price of €99 during the Christmas 2005 selling period. The growing markets of India and China are driving the demand for low cost handsets. The potential purchaser has a plethora of design features to choose from with some suppliers offering a built-in loudspeaker or stereophonic FM radio receiver. Factors which can motivate users to upgrade their existing phones include higher screen resolution which improves the viewing experience and a built in camera which allows pictures to be taken, stored and transmitted. Further enhancements include optical or digital zoom and even a flash provision! The Tri-Band provision enables calls to be made and received throughout Europe and America. Some networks offer the Quad Band feature which permits calls to be made and received throughout the world. It is also possible for some phones to be linked into a Bluetooth system. Some units even have video capture and MP3 playing facilities. The popularity of these add-on features is confirmed by industry statements that 40% of mobile phones in 2005 were fitted with a camera, around 20% also had an MP3 player. Multiband and multimode-enabled mobile phones enable users to make better use of the many differing frequency bands and local standards which exist around the world. 3G systems offer fast data content transfer with transmission rates of almost fifty times those of standard mobile phones. Available features of the 3G system include the ability to download music videos, access traffic information and weather forecasts, download video games and other information. Even phones which offer a limited choice of TV stations to watch television news, and see football highlights, have been on trial. Furthermore, some models enable the caller to see the person they

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Polymers in Electronics

are calling. Some units permit the transmission and receipt of emails and faxes as well as providing internet access and the ability to store tunes. A General Packet Radio Service (GPRS) locator will enable the caller to establish his geographical location, an invaluable aid when seeking assistance from search and rescue services. As the number of features increases the space available inside the handset for electronic components is at a premium and manufacturers are turning to space-saving multiplayer modules to solve their problems. Leading mobile phone operators in the UK include BT Mobile, OneTel, Orange, O2, Tesco, ThreePay, T-Mobile, Virgin Mobile and Vodafone. Strong competition in the mobile phone market has led to heart searching amongst some participants as to whether they should remain in it. For example Matsushita Electric is closing all or part of four factories making Panasonic mobile phones in the Philippines, US, Britain and the Czech Republic with the loss of 1,400 employees who represent half the group’s overseas workforce. The group will be gradually phasing out its 2.5G global system for mobile communications (GSM) handsets which have lost out to price cutting by competitors introducing 3G GSM models. A company spokesman in Tokyo was reported to have said that Panasonic’s share of this market was down to 2.3% in 2005. One looming cloud on the horizon for mobile communications companies is the increasing use of Voice over Internet Protocol (VoIP) which permits internet users to make cheap phone calls via their broadband internet connection rather than using traditional telephone networks. Already Nokia has launched its first mass market 6136 handset which serves as a dual facility, permitting conventional use on a GSM network as well as connecting to WiFi small wireless networks. These operate on an unregulated frequency spectrum. Microsoft’s Windows Mobile operating system already supports VoIP. The power of the new technology is illustrated by the ability of Skype’s seventy five million computer software users to talk to each other free of charge via their broadband. Skype user calls to fixed line phones are significantly cheaper than calls made between fixed line phones using traditional providers. However calls to mobile phones can be very expensive. Hutchison-Whampoa’s three mobile phone networks have announced their decision to sell mobile phone handsets with built-in Skype software. In Europe, the Olla project, a consortium of Philips and Siemens together with European universities and research institutes, is spending €20 million with the objective of building on basic research to develop commercially viable flat plastic light sources. The basic research relates to organic light emitting diodes and organic polymers which emit light when a voltage is applied to them. Targeted applications include IT and lighting.

4.4 Automotive Applications The engine compartment is a particularly hostile environment for electronic components since, taking summer and winter temperature extremes into account, the ambient temperature can range from –40 ºC to +125 ºC. Furthermore the battery voltage can fluctuate significantly about the nominal mean of 12 V. Functions formerly powered by the engine, via pulleys or via a hydraulic system, are now driven by electric motors which invariably need electronic control systems. Whilst many models have employed centralised engine control units the trend is now towards distributed electronics with each component having its individual control unit complete with sensors and fault protection elements.

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Overview of European Electronic Component Markets

Components controlled in this manner include water pumps, brake actuators and power steering systems. Consequently, it is no surprise that the electronics content of each vehicle is increasing and that, for example, the automotive electronics sector is growing. Vehicle manufacturing is now largely a matter of building a car from components and sub-assemblies which are delivered to the production line on a just-in-time basis by Tier 1 suppliers who in turn source components from third parties. The major car manufacturers have hived off their previous in-house component and sub-assembly activities and these are now stand alone businesses anxious to sell, with differing degrees of success, their products to competitors of their previous parents. The French Valeo company, which employs 70,400 people in 26 countries, has been relatively successful with sales up 8% in 2005 to €10.033 billion but a large part of this increase was due to the acquisition of Johnson Controls Engine Electronics. The international basis of the business was underlined by the announcement that it had established its twelfth joint venture in China in 2005. Other automotive component companies are doing less well with General Motors’ former Delphi subsidiary having filed for Chapter 11 bankruptcy protection in October 2005. Visteon is also having problems and in 2005 it transferred 23 loss-making component manufacturing factories back to Ford Motor, its former parent. However, Denso, 23% of which is owned by Toyota, is faring much better and is funding a $185 million expansion of its US electronic components manufacturing plant in Tennessee. Currently plastics represent around 13% of the total weight of a medium-sized car and industry experts believe that 90% of future car design improvements and innovations will have an electronic content such as electronic tyre pressure monitors installed to improved road safety. The ultimate tyre pressure monitor has been fitted to the world’s fastest road car, the Bugatti Veyron 16.4. Its wheel electronics comprise a military grade battery, absolute pressure sensor, temperature sensor, accelerometer micro-controller and radio transmitter/receiver which are housed in a compact wheel housing made from PEEK. Looking ahead to 2007 it is forecast that plastics will represent around 18% of the car’s total weight. Currently approximately 80% of the average car, measured by weight, is recycled. The parts that are recycled are mainly the metal components. The components made from plastics and rubber are frequently being sent to landfill. The End-of-Life Vehicles Directive has aimed to reduce the quantity of material disposed of in this way by setting specific targets for recycling and recovery. Consequently, it is most important that vehicle designers take future dismantling and recycling into consideration at the design stage. With the increasing electrical and electronic content of a car comes an increasing demand for electricity from the vehicle’s power supply system. Maintaining the battery voltage at 12 V has resulted in higher currents flowing through the system and some car manufacturers are now committed to raising the battery voltage to 42 V or even 48 V in the next generation of their vehicle design. The benefit of higher voltage and lower current is greater electrical efficiency because less power will be lost in the distribution system. Nevertheless there will still be sufficient power lost to support an increasing demand for heatdissipating plastics since it is essential to disperse the heat generated in the electronic components otherwise rising temperatures could lead to system failure. However, electronic design changes will be needed to cope with the higher operating voltage. Already the operating voltages of some electrical circuits in hybrid petrol/battery powered cars are reported to be as high as 300 V or even 800 V.

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In the case of the major German passive electronic component manufacturer Epcos, sales into the automotive market segment in 2005 grew by 12% on a year by year basis. Furthermore in the second half of fiscal 2005, the company’s annual report states that the company posted more sales to this industry segment than to any other. Between the third and fourth quarters of 2005 Epcos reported a 30% rise in orders from the automotive electronics industry. According to the European Association of Automobile Manufacturers the reported annual passenger car market in Western Europe was 14.5 million units in 2005 with Volkswagen, whose marques include Bentley, Bugatti and Skoda, selling 1.5 million VW badged cars, putting it ahead of Renault for the first time since 2001. Germany is the major producer followed by France and the UK. The UK car manufacturing industry employs over 215,000 people, the leading plants being those of Nissan in Sunderland, Toyota at Burnaston near Derby and Honda in Swindon. Around 28% of cars produced in Britain are bought in Britain with some 72% being exported. In fact automotive industry accounts for 9.5% of all of UK manufacturing exports by value. The German luxury car manufacturers are doing well with 2005 BMW sales, including Mini and Rolls Royce brands, increasing by 9.9% to reach 1.33 million units and Mercedes, including Smart and Maybach brands, reporting record 2005 figures of 1.22 million units. Asian brands led by Toyota, made the greatest sales gains in 2005. Skoda produced 494,000 cars in 2005 but is hoping to increase production to 600,000 units annually within the next two years. Projects include the launch of a new production line in VW Shanghai in 2007 with a planned joint venture with VW at a new plant being built near Moscow. Skoda also has production plants in Bosnia, India, Ukraine and Kazakstan. The value of the electronic systems in a typical car is said to represent a quarter of its sales value with the figure rising to around 30% for some luxury models. Hybrid models such as Toyota’s Prius, with both an internal combustion engine and electric motors, will have a relatively high electronics content. Wireless hands-free mobile phone installations enhance the electronics content which tends to rise faster in mid-range and, even compact models, than in top-of-the-range models where many of the aspirational features are already fitted as standard. One of the interesting trends in the automotive is market replacement of traditional lighting by LED which can now be made bright enough for this application. LED are already being fitted to cars as a replacement for traditional tail lamps. In 2008 it is planned to fit direct LED car headlights in place of traditional light bulbs because they are less expensive, require less energy take up less space and last longer. DuPont’s Zenite 7130, an LCP reinforced by 30% glass fibre which features a HDT of 289 ºC and low creep at high temperatures, is used by Epcos, for coil bobbins in its range of transformers, chokes and other surface mount devices. Another LCP glass reinforced compound, Zenite 6130L, is used by the Swiss Sonceboz company for coil bobbins and the over-moulding of the stator of its 4000-Series of torque motors. Long-term factors which will increase the electronic content of cars include the arrival of fuel-cell powered cars and the further development of hybrid vehicles where the petrol engine is used to generate electricity using an alternator and the wheels are driven by electric motors, power being stored in

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Overview of European Electronic Component Markets

an intermediate battery. Another version of the system enables the road wheels to be powered either directly by the petrol engine or by using battery powered electric motors to boost its power, the engine performing a secondary role of charging the battery. The latter design uses the petrol engine on its own in cruising condition, utilising battery assistance at low engine speeds, for example, when climbing hills, when the petrol engine is incapable of delivering its full torque. Battery powered assistance is also beneficial when accelerating. The battery is recharged by regenerative braking thus improving the vehicle’s energy efficiency and minimising brake pad wear. This energy efficiency is underlined by claims that Honda’s Insight hybrid is capable of 80 miles per gallon! The system can be further refined by splitting the petrol engine’s power output so that it is divided between driving the road wheels and charging the battery. The version which confines the road wheels to being battery powered is most energy efficient because the petrol engine speed is relatively constant at the level at which it operates most efficiently to charge the motive power battery.

4.5 Fuel Cells From the point of view of polymer usage the types of particular interest are the PEM and the phosphoric acid PAFC designs. The latter design contains the liquid phosphoric acid in a Teflon bonded silicon carbide matrix. In March 2005 Ticona reported that it had produced the first fuel cell prototype built solely with engineering thermoplastics and claimed that this approach reduced the cost of the fuel by at least 50% when compared with fuel cells fabricated from other materials. The 17-cell unit contains injectionmoulded bipolar plates of Vectra LCP and end plates of Fortron PPS. Both these materials remain dimensionally stable at temperatures as high as 200 ºC. The Vectra LCP bipolar plates contain 85% powdered carbon and are made in a cycle time of 30 seconds. The most popular fuel cell design for prototype road vehicles and fork lift trucks is the PEM type which converts the fuel directly into electricity with only water vapour as an exhaust gas. The electrolyte is a solid organic compound in the form of a paper-thin membrane which is sandwiched between an electrically negative anode catalyst and an electrically positive cathode catalyst both of which are composed of platinum particles. The operation of the cell results from the catalytic reaction at the anode which effectively splits the hydrogen fuel into protons and electrons. The positively charged protons diffuse the membrane which acts as a barrier to the electrons which flow through the external circuit as an electric current. The catalytic reaction at the cathode results in the protons and electrons reforming in combination with the oxygen to form water and heat, the latter being dissipated or recycled. Toyota claims to be the first fork lift truck manufacturer to develop a hydrogen powered hybrid fuel cell model. It incorporates double-layer capacitors designed to maximise efficiency by smoothing out the numerous interruptions in current output and input, arising from frequent stopping and starting, and the contribution of regenerative braking. In the UK, UPS Systems has installed a standby power supply system using three PEM cells from Hydrogenics at its Hungerford headquarters. These rackmounted units are able to supply a three phase 10 kW mains power supply. PEM research is being carried out at the Sandia National Laboratories in the US where it has been reported that a membrane material has been developed that will enable micro fuel cells to operate at

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temperatures as high as 140 ºC and produce peak power of 1.1 W/cm2 with a current of 2 A being possible at 80 ºC. This polyphenylene membrane material is able to operate at higher temperatures thus paving the way for smaller fuel cell stacks due to better heat rejection, enhanced water management and significant resistance to carbon monoxide poisoning. PEM fuel cell technology is already being evaluated by leading vehicle manufacturers including DaimlerChrysler, Ford and Toyota. Recently Peugeot Citroën teamed up with the Loughborough, UK-based manufacturer, Intelligent Energy, to test and develop its existing 10 kW proton exchange membrane fuel cell system. The aircraft manufacturer, Boeing, is evaluating this system as a potential power source for a single person motorised glider where, in conjunction with an electric motor, it could replace the current internal combustion engine. One of the inherent problems in some PEM fuel cell designs is the difficulty of initiating operations in sub-zero temperatures. Developments by the ITM Power company in the UK are centred on its patented technology for composite membranes. With these one side can be composed of an acidic polymer whereas the other side is made from an alkaline polymer thus one catalyst may be chosen to operate in an acidic environment with the fuel, the second (different) catalyst operates in an alkaline environment with the oxidant. ITM has also demonstrated direct control of a fuel cell by incorporating a control grid into the junction between the two layers of the composite membrane and using it to control the output of the fuel cell. Other fuel cell membrane materials include modified polybenzimidazole. In the US researchers have developed rod-coil block copolyimides which exhibit high levels of ionic conduction and which can be made into dimensionally stable solid electrolyte fuel cell membranes. These membrane materials are also suitable for use in lithium-ion electrochemical cells. In Japan Kawasaki Steel has developed a new type of carbon filler for use in the plastic separators of fuel cells. It has been obtained by upgrading the company’s mesocarbon microbeads used in lithiumion rechargeable batteries. Work continues on the development of direct methanol fuel cells (DMFC) which are less efficient than proton exchange membrane (PEM) types, but which have the advantage that the anode catalyst draws the hydrogen directly from methanol, thus eliminating the need for a reformer. Panasonic has demonstrated a DFMC cell which is able to power a laptop computer for 20 hours from 7 ounces of pure methanol fuel. However, the commercial launch of this product is reported to be several years away. DuPont offers Nafion fluorocarbon membrane material, conductive plates and gasketing whereas DuPont’s California-based competitor, Polyfuel offers a less expensive hydrocarbon-based membrane material which is reported to be on test with twelve companies including Fujitsu, Hitachi, NEC and Sanyo in their DMFC designs. Polyfuel claims that it has achieved 5,000 hours operation with its membrane which five of the largest Japanese and Korean consumer electronics companies have rated as being the world’s best available portable fuel cell membrane material. UK customers include Johnson Matthey. The partnership of the Japanese mobile phone company, KDDI, together with Toshiba and Hitachi has created a hybrid methanol/lithium ion battery fuel-cell powered mobile phone. The high concentration methanol fuel is stored at the back of the handset which is an adaptation of an AU A5509T design.

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Overview of European Electronic Component Markets

In a comparison with DuPont’s Nafion perfluorinated membrane material whose operation is said to require a humidity level of at least 50% and a temperature below 90 ºC, Polyfuel states that its product will operate at temperatures of up to 95 ºC and humidity levels as low as 35%. Other DMFC development projects include a joint venture between the Japan Atomic Research Institute and Nitto Denko. The partners have succeeded in making the molecular networking of the electrolyte film denser than conventional levels by graft polymerisation and then X-ray crosslinking of the film. This type of film reduces the speed of methanol permeation, a process which degrades the cell’s electricity-generating properties to 10% of the conventional level. This product is targeted at high-performance DMFC designed to be used in mobile phones and personal computers. A report from Kyushu University in Japan [2], revealed that researchers there have developed a nanometre-sized, carbon fibre-based, electrode catalyst for polymer electrode fuel cells (PEFC). This catalyst uses half the platinum used in existing PEFC catalysts with consequent cost savings. Fuel cells with the new catalyst generate power at least equal to that of current PEFC. Previously it was thought that it was difficult to have nanometre-sized carbon fibre hold platinum uniformly at high density. The breakthrough achieved by the researchers was to treat the fibre surface and thereby satisfactorily prevent the platinum from coagulating. Earlier PEFC research by the National Institute of Advanced Industrial Sciences & Technology in Japan [3] had resulted in the development of a new high-performance catalyst to replace platinumruthenium alloy catalysts. The researchers achieved a world-record for high carbon monoxide contamination resistance by using a low-cost organometallic complex as an auxiliary catalyst to platinum. By eliminating ruthenium and using less platinum it was possible to reduce costs to onethird of their former level.

4.6 Computers According to market researcher, Gartner, the 2006 worldwide figure for personal computer shipments is forecast to be approximately 235 million units which is 11% higher than in 2005. Gartner believes that the desktop market has reached saturation with growth coming from the mobile personal computer sector. Flat screens are replacing cathode ray tube designs and the emphasis is on size reduction and obtaining longer battery operating life before recharging is necessary. The individual electronic components which are assembled to make a computer are described elsewhere in this report.

4.7 Contract Electronic Manufacturing The market for electronic components in Europe was dramatically transformed in Europe by the growth in contract manufacturing when a growing number of electronic equipment suppliers opted to sub-contract their manufacturing operations to specialist contractors. Many of these operations have moved to the Far East especially China, the preferred location for high volume assembly. However, in some cases a British or other European company may maintain a domestic manufacturing facility for the production of samples and small batches. The higher cost may well be justified in the case of

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sophisticated high value designs where the customer wishes to operate in close collaboration with his sub-assembly supplier. However, certain niche markets are likely to continue being served by specialist domestic contractors in Europe. These include complex, high mix, low volume PCB and very densely populated PCB especially for customers in the medical and military sectors. One leading UK PCB manufacturer, who prefers to remain anonymous, maintains that his business is sustainable provided he keeps clear of the high volume, low cost sector of the market. Another area where domestic contract manufacturers can retain business is in some just-in-time areas where it is possible to stop or change production at short notice and where it is also possible to incorporate design changes at the last minute. Sometimes design changes are needed to produce replacement units because some of the components originally used are now obsolete and there are no suitable replacements available. This situation can occur with military equipment. According to the Manufacturing Market Insider (MMI), the industry newsletter, the world’s top fifty Electronics Manufacturing Services (EMS) companies reported aggregate market sales of US$94.26 billion in 2005. Ranked number five in world terms the Canadian company, Celestica, reported sales of US$.5 billion. It has over 46,000 employees at its 47 locations across the world of which only one, the Telford plant is located in the UK. In contrast there are eight plants in China. However, the market leader is Singapore-based Flextronics International with fiscal year 2005 sales of US$15.9 billion. Ranked at number four worldwide Solectron, whose operations in Europe generate business worth $1.5 billion, has a worldwide workforce of over 57,000 employees. Solectron has 11 manufacturing sites in Europe of which two are in the UK (Manchester and Dunfermline). At Dunfermline, Solectron describes itself as a medium sized contract electronics manufacturer whose activities include the production of television set-top boxes. Additionally, in Wales, at Cwmcarn near Newport in Gwent, it is reported to own an operation which comprises repair, refurbishment and asset recovery. The Welsh company offers a national collection service and is willing to accept any IT assets under the annex1A section 3 category of the Waste Electrical and Electronic Equipment directive (WEEE). Domestic contract electronics manufacturers are struggling to survive in a market where the major multinationals can shift production to those areas where labour costs are lowest. All is not lost however as the recent management buy-in, buy-out operation of AWS Electronics at Newcastle-under-Lyme illustrates. This contract electronics manufacturer with 270 employees and annual sales in excess of £12 million serves global businesses in the aerospace, communications, defence, food, medical and scientific technology sectors.

4.8 Component Distribution In a recent press interview the Chairman of the UK Association of Franchised Distributors of Components (AFDEC) reported that the total available market for components had fallen by 14% between 2004 and 2005 whilst the rate of decline of the distributor total available component market (DTAM) was 11%. AFDEC expected DTAM to decline in 2006, falling by 2.4% to £1.032 billion from £1.056 billion in 2005. This fall is mainly due to electronics manufacture moving offshore and the demand emphasis moving from data communications to consumer products. Looking forward to

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Overview of European Electronic Component Markets

2007 he foresaw a 2.1% upturn as the UK market re-established itself in core competencies, notably in the automotive, medical and telecommunications sectors. AFDEC was a founding member of the International Distribution of Electronics Association whose activities include the promotion of means to increase the sharing of industry best practice in Europe. Only the largest users buy components directly from component manufacturers. The normal supply route is via stockholding distributors who can invariably offer shorter delivery times often overnight. The best known distributors offer a broad range of products and aim to be a one-stop shop for their customers who can then source their requirements from a relatively small number of suppliers. In some cases distributors concentrate on specialist market sectors. The arrangement also benefits the manufacturer since it reduces the customer numbers and removes the hassle of many individual small orders.

4.9 European Markets – Germany The German economy is the largest in the euro-zone and accounts for one-third of Europe’s Gross Domestic Product (GDP). However, following the reported edict of the new Chancellor, Angela Merkel, the German economics ministry has been instructed to abandon its habit of producing overoptimistic growth forecasts. In its 2005 Annual Report and Accounts, Epcos, the leading German passive electronic component manufacturer, reported that its problems in the first half of the year were significantly affected by the propensity of German citizens to save rather than spend with the result that large quantities of consumer goods were lying in warehouses. The natural response of manufacturers had been to slow down production and reduce component orders. In consequence component manufacturers were producing at below optimum rates and making losses since the oversupply situation was also putting pressure on prices. The situation improved in the latter part of the year and manufacturers are now more optimistic about the future. A feature of the German market, and also of some other European markets, is that despite the product being made in Asia, the design and component specification functions remain in Europe. Nevertheless the trend to move production capabilities, and sometimes development capabilities, from Europe to Asia is still strong. However, in some companies, including Siemens and DaimlerChrysler for example, there are reports of the employers negotiating cost cutting deals with their employees as an alternative to moving production facilities to countries to the east of Germany. Lower pay, longer hours or other factors, are linked to an undertaking not to announce redundancies before 2012 or some other specified date. In Germany unemployment at 8.4% still remains a problem but less of a problem than in 2005 when it was 10.4%. Unlike the experiences of some of its European partners Germany’s reputation for high quality engineering products has boosted its exports to China which have reportedly risen by 500% over the past decade. The German consumer sector will benefit in 2006 from the government’s decision to raise the VAT rate in 2007 by 3% since consumers will bring forward their purchasing plans to the detriment of the economy in 2007. Another spending boost this year will come from increased sales of large screen television sets bought by German citizens to follow the progress of the football world cup!

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Far more attention is given to recycling in Germany than in England and it is interesting to note that several trade associations have banded together there to form a new company, TECPOL. The objective of this company is to develop technology to recycle speciality plastics.

4.10 European Markets – France Sales of electronic components to the automotive sector are particularly important. In 2005 they suffered a downturn due to a 5.6% decline in Renault’s sales and a 2.5% fall at Peugeot Citroën where Peugeot brand bore the brunt of the decrease. The decrease is partially due to the age of some models. Doubtless, when their replacements are launched, the new models will have a higher electronics content. One interesting development was the success of Renault’s Romanian Dacia brand whose main Logan model, though designed for emerging markets, recorded sales of 13,678 units in France, Germany and Spain.

4.11 European Markets – Italy The Italian economy is recovering after a steep fall at the end of 2004 with a low point recorded in early 2005. As in other European markets companies are tending to move their manufacturing plants abroad with small to medium sized companies favouring Eastern Europe whereas the larger companies favour Asia. The Italian National Federation of Electrotechnical and Electronic Industries, (AssoAutomazioneGISI) carried out a 2005 analysis of the market situation in the automation, industrial, civil and laboratory instrumentation sectors as well as the public utility and traffic networks. They estimated that overall sales growth in 2005 would average 2.5%. They were cautiously optimistic as far as 2006 was concerned. However in Italy official statistics do not reveal the complete picture because of the strength of the ‘black’ economy whereby ‘invisible’ tax-evading transactions take place. The magnitude of the problem, according to alleged reports of a confidential Inland Revenue memorandum, is illustrated by the figure showing that €46 of turnover is withheld for every €100 declared to the tax authorities. In another way Italy differs from its European market partners to the extent that its plastics and rubber manufacturing sector in Italy contains many small family owned businesses. These are frequently export orientated and keen to use the best available technology. One of Italy’s leading plastics companies is the Polimeri Europa subsidiary of Eni, the country’s leading energy company with around 71,500 employees and operations in 71 countries and whose preliminary 2005 sales figure was €74 billion with reported net profit up 24% to €8.8 billion. Polimeri Europa comprises the three divisions of Basic Chemicals, Polyethylene and Elastomers and Styrenics. In 2004 its sales income was €5.4 billion. It employs around 6,400 people at facilities in Italy, Belgium, France, Germany, Hungary, Portugal and the UK (Grangemouth and Hythe).

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Overview of European Electronic Component Markets

4.12 Other European Markets The importance of Nokia to the Finnish economy is indicated by the fact that this company accounts for one-fifth of the country’s exports and one-third of Finland’s total investment in research and development. Therefore the movement of manufacturing operations has a significant impact on the country’s economy. Production is being transferred to Hungary, India and China for example. Recent events include 600 redundancies from the 3000 strong workforce at the Perlos factory in Finland which makes plastic components for mobile phones. New members of the European Union are benefiting from such trends including Poland where the plastics industry enjoys one of the world’s fastest growth rates, increasing, on average, at the rate of 15% per year.

References 1.

UL 94, Tests for Flammability of Plastic Materials for Parts in Devices and Appliances, 2003.

2.

Japan Chemical Week, 2005, 46, 2322, 2.

3.

Japan Chemical Week, 2004, 45, 2288, 1.

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5

Key Trends and Developments

5.1 Bluetooth Technology The phenomenal growth of Bluetooth short range wireless technology continues with estimates of 100% market growth from 2004 to 2005 when more than 275 million were reported to have been shipped. This networking standard, which was named after a 10th century Danish king, Harald Bluetooth Gormson, allows personal computers, laptops, handheld computers, mobile phones, printers and other electronic controlled products to communicate with each other by means of radio links of up to ten metres. Three classes of radio performance are available: •

Class 1 with a maximum output power of 100 mW and a working distance of 100 metres.

•

Class 2 with an output of 2.5 mW and a working distance of 10 metres.

•

Class 3 with an output of 1.0 mW and a working distance of 1 metre.

No interconnecting cables are needed. The Bluetooth technology also allows domestic appliances, home heating and other systems to be included thus permitting the coordinated control of everything electrical within the home from a personal digital assistant (PDA) which also combines the functions of calendar and address book. The UK Cambridge Silicon Radio company (CSR) is a world leading, provider of the technology and shipped 150 million units in 2005 with electronics company users including Apple, Dell, Nokia, Panasonic and Sony. Growth markets include voice-over-internet protocol (VoIP) telecommunications application, stereo headphones and automotive hands-free mobile phone applications and other uses where Ford, Nissan, Renault and Toyota are reported to be interested.

5.2 Organic and Other Polymer Developments Environmental concerns which have encouraged the use of biodegradable plastic bags by supermarkets are now influencing the electronic components market. The Japanese Pioneer Corporation is now making optical storage disks using corn-starch-derived polylactic acid (PLA) which, unlike PC, is obtained from the fermentation of biomass and which is almost totally biodegradable when buried in soil. Toray Industries is also making PLA, branded as Ecodear. It has, in collaboration with Fujitsu Ltd., and Fujitsu Laboratories Ltd., produced what has been claimed to be the world’s first large plastic case, using PLA resin, for Fujitsu’s FMV-Biblio NB80K notebook computer. Toray has also developed what is claimed to be the world’s first flexible PLA film for wrapping and other applications. PLA may also be alloyed with high Tg PC and a non-halogen flame retardant to produce a material which is used to make notebook computer casings. The microdispersive alloying with PC results in a compound with good heat resistance, mouldability and durability.

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Other manufacturers of PLA based products include NEC which uses it as the main component of its bioplastic which has the world’s best flame retardance for a product of this type. This has been obtained without the use of halogenated or phosphorus-based flame retardants. The proprietary property-modifying additives employed in the bioplastic by NEC include inorganic heat adsorbents, high-flow modifiers and impact modifiers. The material conforms to UL 94 5V standard thus enabling it to be used in a wide variety of electronic products including personal computer housings. NEC has also reinforced PLA with a 20% loading of Kenaf, a natural plant fibre from Hibiscus cannabinus L., to obtain a high strength reinforced bioplastic. The fibre reinforcement is claimed to raise the polymer’s deflection temperature under load from 67 ºC to 120 ºC and increases bending modulus from 4.5 GPa to 7.6 GPa. The fluidity and moisture resistance of the polymer are said to be unaffected. NEC is reports that the heat resistance and strength of the reinforced polymer exceed that of glass-filled ABS. In partnership with Unitika, NEC has developed the reinforced PLA case for the DoMoCo N701i ECO mobile phone case. NEC claims that the material used achieves a biomass ingredient ratio of 90% which is the highest level of any bioplastic used in electronic devices. To achieve this figure the partners have added a biomass-based ‘flexibiliser’ and reinforcement filler to secure the simultaneous benefits of heat resistance, high fall impact durability and ability to be moulded. Elsewhere in Japan, Mitsubishi and Sony have teamed up to develop a flame retardant PLA resin which uses a UL 94 [1] V-2 rated aluminium hydroxide RoHS compliant flame retardant. The new material is claimed to be as strong as ABS and, by using additives and by adjusting moulding parameters, Sony is able to process it to make front panels for its stand-alone DVD players using conventional injection moulding presses employing commercially viable cycle times. Bayer is linked to the electronics industry via its HC Starck subsidiary which is a leading supplier of tantalum powder to the electrolytic capacitor industry. It also supplies the Baytron P transparent conductive polymer which can be used to manufacture organic light-emitting diodes (OLED). Innovative developments by the US Plextronics conductive polymer company include an OLED designed to compete with incandescent and fluorescent lamps. The company is also working on solar cells where inherently conductive polymers are the key ingredient to replace silicon. The US Department of Energy (DOE) is funding research into the potential of white OLED to save energy in commercial and residential lighting applications. In achieving a record device efficiency of 25 lm/W, Osram claims to have made a breakthrough in polymer-OLED technology. Osram claims that its OSTAR product is the brightest LED on the world market with the added advantage of featuring continuously controllable dimming. Osram has also claimed to have developed the first polymer-OLED ‘tunable’ light source which is reported to allow colour tuning and true freedom for illumination design. In order to achieve the high blue colour efficiency of 14 lm/W, a phosphorescent blue emitter was embedded in a polymer host. The tunable light source is based on three separate, printable polymer inks which emit in the red, green and blue parts of the spectrum. Osram Opto Semiconductors and Avago Technologies (formerly the Semiconductor Products Group of Agilent Technologies) have signed a limited patent cross-licence agreement. This allows Avago to manufacture and sell white LED with special conversion technology whilst Avago has granted Osram a patent licence covering LED systems or projection and flat panel LCD.

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HC Starck is also involved in another significant development, the synthesis of poly(3,4ethylenedioxythiophene) (PEDT) by in situ oxidative polymerisation or as a complex with polystyrene sulfonate as a template. There are a growing number of electrical and electronic applications for this material including antistatic coatings, capacitor cathodes, through-hole plating, OLED, organic field effect transistors, photovoltaics and electrochromics. New developments relating to the manufacture of thin film transistors (TFT) are being reported from Japan where the Tokyo Institute of Technology has developed a flexible, transparent device on a PETP substrate. This TFT comprises an amorphous oxide semiconductor, which serves as the active layer, and which is made from indium, gallium and zinc oxide deposited by laser ablation to a thickness of 30-60 nm. The TFT, with its transparent electrodes and circuitry, is manufactured in a vacuum at a temperature of 150 ºC or less. Because of this low processing temperature it is possible to use low cost PET film, with a thickness of 200 μm, as a substrate thereby enabling transistors to be manufactured at a relatively low cost. The search is always on for new, more cost effective alloys and, in Japan, Sumitomo Chemical and Yamagata University have developed a unique plastic alloy which is environmentally friendly, lower priced, has better heat resistance and better electrical properties than comparable products currently being marketed. The new alloy has been derived from the combination of polyphenylene (PPE) with an ethylene-epoxy copolymer. Furthermore, the compound’s structure has been controlled to improve its processability. Possible uses include insulation films and housings of mobile phones and other electronic appliances. In the field of new developments scientists at Durham University have produced a polymer, PANiCNQ, which is ferromagnetic at room temperature. Whilst some consider PEEK to be the polymer of last resort there is also polyether ketone ketone from the US Oxford Performance Materials Inc. This material has a high softening point and is capable of maintaining high strength, wear resistance and chemical resistance even in continuous use at high temperatures. Current applications include the aerospace industry.

5.3 Supercapacitors Supercapacitor, despite being an NEC trademark, is the European designation for the product which is known in the US as an ultracapacitor, ultracap or even an electro-chemical double-layer capacitor. All these terms are interchangeable. Supercapacitors, which are capable of storing up to a hundred times more energy than traditional capacitors, act like batteries but without the handicap of ESR. They are able to deliver high pulses of power with charge-up and discharge times which can be measured in seconds. Operating voltages tend to be between two and three volts. It is therefore necessary to connect them in series with the addition of circuitry to ensure voltage sharing between individual units. Applications include their use in vehicle engine starting where they have the ability to deliver energy faster than a comparable battery. They can also be used to store energy generated by vehicle regenerative braking systems and will also store energy in mobile phones and cameras. The fundamental basis of supercapacitor design is to have two activated carbon electrodes immersed in an organic electrolyte. The electrodes are separated by a membrane which permits mobility of ions whilst preventing electronic contact. The range of available electrodes now includes metal oxides and

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conducting polymers. Leading manufacturers include Epcos and Maxwell Technologies whose product range comprises capacitance values of 2,600, 1,800, 900, 450, 100, 10 or 4 F. The gravimetric energy density of a supercapacitor may be between 1 and 10 Wh/kg which is high in capacitor terms but only around a one-tenth of that obtainable from a nickel/metal hydride battery. Maxwell Technologies intends to increase the rated voltage by up to three volts within the next few years. Some Maxwell prices are coming down with the launch of low versions including the 2600 F MC2600 model which made the cost of one US cent per farad a reality. Maxwell is now broadening its range of low cost models in the 650 F to 3000 F adding some modules which combine multiple cells. Amongst Maxwell’s recent sales successes has been the order from Enercon for 1.5 million units to be used in wind power, blade pitch systems. Each of the turbines has three blades and incorporates between 200 and 700 Boostcap supercapacitors to provide back-up power. The potential growth of this market is illustrated by information from the European Wind Energy Association showing that wind power capacity in Europe exceeded 40 GW in 2005, a figure five years ahead of official targets. The capacity rose from 34,372 MW at the end of 2004 to 40,504 MW at the end of 2005. Despite its sales successes Maxwell reported a net loss of $7.1 million on 2005 fiscal year revenue of $45.4 million. However the company is investing in additional manufacturing capacity to cater for growing demand for its products. It is also finalising plans for high volume manufacture offshore, and expanding its product range. The advantages for the use of intrinsically conducting polymers in electrochemical capacitors rather than carbon-based or mixed metal oxide electrodes may be summarised as follows: •

They have extremely long operating lives of at least 10 years, comprising at least 500,000 charge/discharge cycles and energy densities several orders of magnitude higher than conventional electronic capacitors. However, self-discharge rates are relatively high. For example, when using an organic electrolyte (the worst case) the full charge will fall to 50% within 30 to 40 days.

•

Supercapacitors have minimal contact resistance because the conducting polymers can be synthesised directly on to the current collector. The electrode material can be formed as thick films, powders or sub-micron coatings with the latter offering the possibility of diffusion times of the order of microseconds.

•

Electrochemical capacitors operate partially by the known concept of doping and undoping of polymer electrodes. This concept is used to promote the fast and efficient shuttling of the ions between the polymer and the double layer created at the electrode/electrolyte interface. The anions and cations involved in these double layered electrochemical types are contained within the electrolyte. Conducting polymers are invariably used in the case of solid electrolytes. Some designs utilise liquid electrolytes which are usually in aqueous or organic solution. The difference between electrochemical and conventional electronic capacitors is that is that ions perform the charge transfer in the former type and by electrons in the latter type.

•

The use of large surface areas, which can be increased by adopting multilayer designs, and the high intrinsic conductivity of the material confer both high power and energy densities. A further benefit is the ability to produce conducting polymers on a large scale at relatively low cost. When assembling stacks of individual cells, previous problems of high internal resistance can be resolved, by applying a controlled high pressure to the stack.

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•

Bringing nanotechnology into supercapacitor design is expected to result in dramatically improved performance. In the meantime more competitive pricing is increasing sales. In Germany EPCOS are supplying supercapacitor modules for the BMW X3 model.

New research at the MIT’s Laboratory for Electromagnetic and Electronic Systems (LEES) by Schindall, Kassakian and Signorelli produced some battery alternatives [2]. The research is dedicated to replacing the activated carbon electrodes with vertically aligned single-walled carbon nanotubes thereby significantly increasing the effective surface area of carbon with a consequent significant enhancement of storage capacity. The objective of nanotube-enhanced supercapacitors is to combine the long life and high power characteristics of the present generation of supercapacitors with the higher energy storage density normally only available from a chemical battery. In the UK, Hampshire-based Nanotecture, working in collaboration with Johnson Matthey and HILTech Developments, has been awarded a £375,000 government grant for its Next Generation Super-Capacitor for Hybrid Vehicle Applications R&D project. The project will use nanostructured material, containing nanopores, which has been developed by Nanotecture.

5.4 Solar Cells Government energy conservation and carbon dioxide reduction policies in the UK and other European are driving the trend to employ more environmental means to generate electricity. In Wales, for example, the Bronllys hospital in Powys now satisfies approximately 10% of its power demands from its photovoltaic panels. A 60 kW array of 485 grid connected Kyocera 125 Wp 0.929 m2 solar photovoltaic modules, costing £271,000 and installed on the hospital’s south facing roofs is reported to have saved 40 tonnes of carbon dioxide emissions in the year to March 2006. Any surplus energy generated by the panels is returned to the grid supply. The solar photovoltaic market has been an area of high growth for the past nine years culminating in a 27% increase in 2005 when the world solar cell market was estimated to be worth around five billion dollars. The world’s major solar cell producers include BP Solar, Deutsche Cell/SolarWorld, Isofoton, Kyocera, Mitsubishi Electric, Q-Cell, RWE Shott, Sanyo, Sharp, Shell Solar and Suntech Power. It is significant that the world’s major oil companies are heavily involved in solar power. In a recent statement Norm Taffe, the Executive Vice-President of the Consumer and Computation Division of Suntech Power’s Cypress Semiconductor parent company, predicted that solar power could be competitive with mainstream electricity generation in five years’ time. BP has reported that its solar panels currently produce more thn 100 MW of energy in the US, Spain, India and Australia. This figure is set to double by the end of 2006. The group’s BP Solar subsidiary is forecast to generate revenues of $1 billion by 2008. Solar cell sales have been assisted in the Germany, the UK and other countries by government subsidies. A joint venture between the US Evergreen Solar and Germany’s Q-Cells has been established to build a solar cell production facility in Thalheim in Germany. Germany’s major solar company, Solarworld, has solar wafer and panel manufacturing facilities in Freiburg. Amongst the interesting new developments is a project by Powertile to produce photovoltaic roofing tiles. In an interesting application, which also involves photovoltaic nanotechnology, Konarka Technologies has developed a form of photovoltaic plastic sheeting, incorporating nanomaterials, which is able

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to generate energy from both sunlight and indoor light. The material is made by coating or printing photoactive materials on to a thin flexible plastic substrate. The company has secured a US Department of Defense contract whose objective is to assist soldiers to recharge batteries in the field. The material may also be incorporated into tents and other structures to enable electricity to be generated silently. The process can imprint different colours on to the material and so, in military applications, may be used to produce tents in camouflage colours. The use of flexible solar panels on clothing is also the subject of a three nation European development project called H-Alpha Solar whose partners include Akzo Nobel, which has established a pilot plant to produce rolls of silicon cells which are 40 cm wide. Whilst of a similar construction to a conventional solar cell, this type is only 1 μm thick as a result of depositing polymorphous silicon at high pressures and temperatures. Nanotechnology is also being used in solar cell research at the Penn State University in the US where the use of titanium oxide nanotubes currently gives 3% energy conversion efficiency. Researchers including Professor Craig Grimes are seeking to raise this figure to 15% utilising a relatively simple manufacturing process. The technology involves the direct abstraction of hydrogen from water using uv light. In effect sunlight shines on water covering the new material which splits into its hydrogen and oxygen constituents. The largest research project in the history of solar energy is targeted towards the creation of very high efficiency solar cells with reasonable manufacturing costs and efficiencies in excess of 50%. The project is being led by the University of Delaware with support from the US Defense Advanced Advanced Research Projects Agency. Research at the University of Toronto has been targeted as a means of capturing infra red light from sunlight with the objective of boosting the energy-capturing efficiency of solar cells. The solar cell being developed by the Toronto research group comprises an electroconductive polymer matrix, typically using polythiophenes, which contains nanoparticles able to capture infra red light. At the Wake Forest University in North Carolina successful research has been based on the creation of a micron scale structure made from a mixture of a polymer and nanostructures (C61 fullerenes). The technology involves the use of a novel annealing technique and is able to attain conversion efficiencies in excess of 5%. Similar results have been achieved by teams at University of California laboratories in Los Angeles and Santa Barbara. Other work on the use of nanocomposites to manufacture solar cells is being carried out at Columbia University and the Lawrence Berkeley National Laboratory which have granted Nanosys worldwide exclusive rights to commercially exploit the technology. One of the problems facing manufacturers of polymer-based photovoltaic cells is their low light-to-energy conversion efficiency of 5% maximum, whereas multi-junction crystalline silicon-cells have achieved a figure of 37%. One of the flexible plastic solar cells exhibiting the 5% efficiency contains zinc oxide.

5.5 Flat Panel Displays The competition in this sector is hotting up as the advocates of the various technologies battle it out on issues of price and specification. One battle casualty has been the market for conventional CRT whose prices have been under pressure as demand has fallen due to the impact of the new

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technologies. In the television sector where larger and larger screen sizes are on offer the law of unintended consequences has come into play. It has been reported that HDTV sets may deliver a picture of inferior quality to that of the analogue sets they replace. This is because of transmission compromises due to multiplexing whereby multiple digital channels are broadcast simultaneously thus reducing signal quality in a manner apparent to the viewer. Apparently producers of some programmes have made compromises in the technical standards of their programmes and these too are revealed to the viewer owning a new generation set. The popularity of the new flat and plasma television is supported by industry estimates that nearly a million UK homes now have them. However, high quality results will be achievable from playing DVD and by tuning into the coming HDTV transmissions which were promised by Sky Television in time to view televised World Cup football matches which began in June 2006. During the course of 2006 the number of homes able to receive HDTV transmissions is forecast to rise from 700,000 to 2.1 million. The BBC is also planning to launch HDTV transmissions possibly via its joint FreeSat satellite service which is being launched in partnership with ITV. Arguably the ultimate system, whose commercial launch may be many years away, is the Super HiVision system developed by the Japanese public broadcasting system, Nippon Hoso Kyokai. This offers a 16:9 aspect ratio picture with 4320 horizontal lines! The magnitude of this achievement is underlined by comparison with HD which has 1080 horizontal lines, semi-HD with 768 horizontal lines and current analogue with 625 horizontal lines. In the opinion of the US Consumer Electronics Association HDTV sets will outsell analogue sets by a margin of 89% in 2006 with total net sales of 15.9 million. In cash terms, digital TV sales increased by 60% to reach $17 billion in 2005 with flat panel displays, including LCD and plasma options, accounting for 40% of this figure. LCD have traditionally dominated the flat panel display market along with active matrix LCD (AMLCD) which were originally designed for the personal computer market. One of the largest manufacturers in this sector is the Korean Samsung company whose S-LCD joint venture company with Sony of Japan produces 100 cm and 115 cm LCD panels for television sets. A new Samsung South Korean panel producing plant at Tangjung is believed to have opened in January 2006, three months ahead of its scheduled April 2006 opening. The new plant is located alongside the S-LCD plant which opened in April 2005. This new seventh generation plant accepts glass sheets measuring 190 x 225 cm which can subsequently be subdivided into either eight 100 cm panels or six 115 cm panels. This ‘mother glass’ process is preferred because the company prefers to handle a smaller quantity of large glass sheets rather than a much larger quantity of smaller sheets. The plant built in 2005 can process up to 60,000 large sheets per month whereas the new plant will be able to handle 90,000 sheets per month when fully operational in the second half of 2006. LG Philips LCD, the joint venture which claims to be the world’s second largest flat screen maker, has reported strong sales growth with growth being stimulated by the televising of the Winter Olympics and World Cup in 2006. The company plans to invest $4.2 billion in 2006 on the expansion of its production facilities which are optimised for 105 cm and 120 cm LCD TV panels. New LG Philips LCD mass production facilities opened in January 2006, three months ahead of schedule. Recently LG Philips LCD claimed to have developed and produced the world’s largest TFT LCD panel at its South Korean plant at Paju. The area of this 255 cm HD display panel is approximately 50% greater

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than that of the largest currently available LCD panel. It offers 6.22 million pixels and can produce 1.07 billion colours with a response speed of 5 ms. There is still strong competition from plasma displays in this market segment which could affect sales. Philips has been suffering from the downturn in demand for CRT which has culminated in the insolvency of LG Philips Displays, the world’s largest manufacturer of television and computer display CRT with an estimated 25% world market share. The continuing investment in LCD panel production along with improvements in manufacturing technology, now reported to be sixth generation, is destined to reduce unit costs thereby reducing TV set prices and consequently stimulate market demand. Furthermore the Beijing location of the 2008 Olympic Games will certainly stimulate sales of TV sets in China. On Friday January 27th 2006 Hong Kong based LG Philips Displays, the joint venture of Philips of the Netherlands and Korea’s LG electronics, stated that it could no longer honour certain debts and that it had sought court protection for its Dutch subsidiary and its German affiliate in Aachen. The venture’s units in the Czech Republic, France, Mexico, Slovakia and the US were reviewing their financial position with around 750 jobs being involved. Despite LG Philips’ problems, Sony is continuing to sell television sets with CRT in emerging markets. One of the largest available LCD TV sets, currently available in Japan priced at $15,560, is a 165 cm version from Sharp another investor in expanded LCD production. The Japanese Sharp group is the world’s largest LCD TV manufacturer and has been so successful that it has been unable to meet the market demand for its TV sets. Consequently it is negotiating to buy flat panels from two Taiwanese companies Chi Mei Optoelectronics (CMO) and Quanta. Up till now it has zealously guarded its LCD technology but is now prepared to cross-licence some of its LCD patents. In the case of CMO the agreement is planned to relate to small TV and personal computer panels, Quanta will produce personal computer panels. Sharp will retain the technology intensive large screen TV panel operations in-house. The panel shortage comes despite a 20% production increase in Spring 2006. Sharp has prioritised the Japanese market where it has a 40% market share at the expense of the US where its market share has fallen from 25% to 18% because of the shortage. Sharp has planned to increase its global TV shipments from four million units in the year to April 2006 to six million units in the 2006-2007 year. In the field of flexible plastic screens the largest model Samsung has produced is believed to be the 17.5 cm (640 pixels by 480 pixels) prototype which comprises an amorphous silicon TFT which is attached to a colour filter. LCD panels need a light source, with a typical service life of 2000 hours, to illuminate them and the market has until now been split with LCD displays serving screen sizes up to around 100 cm whilst plasma display panels (PDP) are employed for larger screen sizes. Colour displays are available in two formats. TFT displays are normally used in applications which require a fast response time whereas colour super-twisted nematic (CSTN) is better suited to lower budget applications which do not necessarily require the fast response time. Twisted nematic (TN), super-twisted nematic or supertwist (STN) and film super-twisted nematic (FSTN) are monochrome displays to which colour can be added by varying the backlighting colour and effects such as the use of negative and positive images.

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The overlap between the two technologies is increasing as LCD screens get bigger and plasma screens appear in smaller sizes. Development of the LCD backlighting technology continues with researchers in Japan producing what is claimed to be a highly efficient thin backlight (HSOT-II) with an array of microprisms, at its base, in a direction parallel to that of a cold cathode fluorescent lamp. The polymer used in the backlight is PMMA containing spherical silicone microparticles. Unlike LCD, with their backlighting, the pixels in a plasma display are light sources in their own right. Consequently as the screen size shrinks, the pixels are smaller and generate less light resulting in a picture lacking in brightness. Smaller PDP were exhibited by Pioneer and Panasonic at the Ceatec 2005 exhibition held in Japan. Hitachi exhibited a 140 cm PDP with full high-definition resolution defined as 1080 horizontal lines whereas semi-HD screens feature 768 lines. The largest plasma screens currently available are 215 cm designs with a 16:9 widescreen aspect ratio. Earlier designs had a service life of 10,000 hours but current designs will perform for between 20,000 and 30,000 hours with brightness levels at this time tailing off to around 50% of level when new. Hitachi is also boosting its plasma panel production plans to treble its monthly output to the equivalent of 300,000 105 cm units by the end of 2007, the original target date was March 2009. The investment is being made by the Fujitsu Hitachi Plasma Display joint venture, which is 80.1% owned by Hitachi. Matsushita, best known in retail outlets for its Panasonic brand, is planning to invest, with its Toray chemicals group partner, $1.57 billion in the construction of what is set to be the world’s largest PDP plant as a means of establishing market leadership of the flat-screen television market. The plant, with a planned annual production capacity of six million panels, is scheduled to open in 2007. Matsushita will then have an annual production capacity of eleven million panels placing it in the position of world number one ahead of Korea’s SDI company. One of the pioneers of passive matrix LCD technology using, what is claimed to be, a unique bi-stable LCD, is Malvern-based ZBD Displays, a spin-off company from QinetiQ, the former Government Defence Evaluation and Research Agency. The zenithal bi-stable display uses a simple microstructured grating surface to control the alignment of the liquid crystal molecules. There are two stable orientations for the molecules, black and white. This technology is said to be easily adapted to existing LCD production lines and claimed to be ideal for plastic substrates making roll to roll production feasible. The system uses a master to stamp the required profile into a deformable material thereby producing a perfect replica. ZBD claims to be the first company to apply this allegedly simple technology to the inner surfaces of LCD. High quality images can be retained indefinitely on the screen of the device, power is only consumed when the image changes and so small batteries may be employed. The company has already raised £10.4 million of development capital. Investors include QinetiQ Ventures and the Dow Chemical Company. The system has been on trial at John Lewis’ Peter Jones store in London where the technology was used for the automated updating of price and product information without the need for in-store paper labels. The updating process was carried out using a simple wireless network thus reducing the operational overheads incurred when using paper labels. A similar trial was successfully carried at a Tesco store in Leicester.

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New LCD technology from the US manufacturer Hewlett-Packard allows the low cost production of ultra-high resolution screens, which draw no power once an image is displayed. The company’s engineers discovered that when liquid crystals are put in contact with polymer ‘posts’ smaller than 1 μm across, the rod-like liquid crystals naturally align themselves around the posts either horizontally or tilted upward in a spiral around the post. Applying an electric field switches their position from horizontal (a dark pixel) to tilted (a lit pixel). Since both of these states are stable the liquid crystals stay where they are when the field is removed. Another technology, where major advances have been reported, is that based on PLED and which claims to be the fastest growing new technology destined to replace LCD and the use of cathode ray tubes according to its leading developer, Cambridge Display Technology (CDT). PLED offer 160 degree viewing angles with 100:1 contrast ratio. Recently, in partnership with Sumitomo, CDT announced two further milestones in the development of light emitting polymers (LEP). A phosphorescent red device has been produced with a 500,000 hour lifetime from 100 to 50 cd/m², the second milestone has been a 150,000 hour lifetime for a fluorescent blue polyfluorene material with the highest recorded efficiency of 10 cd/A. Founded by Cambridge University, the company has received numerous awards for innovation and is now quoted on the US-based NASDAQ stock exchange. It has used its technological leadership to forge partnerships with the leading players in the display and related fields by means of technology transfer and licence agreements. In addition to its Cambridge offices and a Technology Development Centre at Godmanchester, approximately fifteen miles away, the company has a California-based subsidiary the Litrex Corporation at Pleasanton. CDT has also established an Asian office in Taiwan. One of CDT’s earliest partners was Seiko Epson who has gone on to produce a prototype 100 cm full colour display, using ink jet printing to deposit the organic material on to the substrate which may be glass or plastic. The polymer organic light emitting diode (P-OLED) manufacturing technique involves the application of a thin film of light-emitting polymer on to the substrate which is coated with a transparent electrode. A metal electrode is then sputtered or evaporated on to the polymer. Subsequently, the application of a magnetic field between the two electrodes results in light emission from the polymer. Developments in ink technology go hand in hand with the advance of inkjet printing technology to produce flat panel displays. Avecia Ltd is involved in the development and evaluation of aqueous, oil-based and UV cure types. The selection and formulation of a particular type will be governed by the attributes required by the application. Two examples of the products available to the display manufacturer are given by Avecia. One is a 100% solids UV-cure ink which contains a blend of monomeric and oligomeric acrylates which are polymerised using UV light in the presence of a photoinitiator. The other example involves the jetting of inks containing LEP such as poly(p-phenylene vinylene) to produce low cost, energy-efficient displays. Other applications for this technology include a green P-OLED display for the control and indication of all the system operations on a personal MP3 music player produced by the US Delta Electronics company. CDT’s MicroEmissive Displays licensee has developed a P-OLED display for the amazing NHJ 3-in-1 camera which combines MP3 player, still and movie cameras into a single 3.2 million pixel product which incorporates a USB connection.

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MicroEmissive Displays plc, a 1999 spin-off company from research carried out at Edinburgh University, shipped the first delivery of polymer-on-silicon microdisplays from its Edinburgh base in December but when the Alternative Investment Market (AIM) listed company moves to volume manufacture of its second generation products, they will almost certainly be made in the Far East with production available from the first half of 2007. In the meantime limited manufacture of the existing products will continue at the Edinburgh plant. Fund raising has been successful with a reported net cash holdings of £10.4 million as at 30th June 2005. Investors include BASF Venture Capital. University spin-off companies continue to make news and Cambridge-based Screen Technology Ltd, a 1996 Cambridge University spin-off which raised £8 million at its AIM debut in August 2005 is no exception. The company’s shareholders include Thomas Swan Ltd, the Consett Co., Durham, UK manufacturer of Elicarb single wall and multi-wall carbon nanotubes. Swan’s nanomaterials manufacturing capabilities are supported by research and development collaboration with Cambridge University’s Departments of Material Science and Chemistry. The company’s ITrans product is a high quality large format display screen which is claimed to rival existing LED and Plasma products. The current annual market for this category of product has been estimated to be £1 billion, rising to £1.5 billion by 2010. Target markets include advertising, indoor venues, retail outlets, shopping centres and transportation where screen sizes exceeding 205 cm and a minimum of 1024 x 768 pixels are required. The current product range extends from standard formats of 170 cm wide to widths in excess of 510 cm. Philips is also incorporating PLED technology into its products which include the model 639 mobile phone with a clam shell which when closed allows incoming calls to be indicated through the outer mirror surface. A recent Philishave men’s shaver uses a PLED display to indicate shaving time remaining before the battery needs to be recharged plus other information. In another PLED application Philips has combined a 25 μm polymer electronics-based back plane with a 200 μm front plane made of reflective ‘electronic ink’ to form a thin roll-up display screen described at its launch as the thinnest and most flexible display yet achieved. Known as Polymer Vision, this Philips venture has the capability to robustly fabricate large arrays of polymer based TFT with largely identical electrical characteristics. CDT’s technology may also be used in reverse to act as a photovoltaic cell and CDT has filed several patents in this area. Early products include digital clocks powered by CDT’s polymer solar cells. The company is developing the technology, based on work at Cambridge University’s Cavendish Laboratory. A completely different HDTV flat screen technology was revealed to the public in September 2005 when Canon demonstrated flat panel television sets using its surface-conduction electron-emitter display (SED). The technology is based on the traditional CRT as used in current television sets. However, in this case the traditional vacuum tubes have been miniaturised to the extent that thousands of them have been packed inside a flat panel display which is between 10 and 12.5 cm thick. In fact there are actually as many electron emitters as there are pixels on the screen - a situation which is claimed to deliver brighter, sharper and clearer pictures with added bonus of having a longer service life than LCD or plasma sets. Other benefits include power consumption up to one-third less than plasma display television sets.

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Prototype sets were branded as Canon but, at the time of the September 2005 public demonstration of its SED technology, it was not confirmed whether Canon would enter the market under its own name or whether it would licence others to use the technology. Canon already has an agreement with Toshiba which is expected to be the first company to launch TV sets incorporating the new technology. Philips’ Polymer Vision display technology involved the development of a flexible active matrix monochrome, electrophoretic display which is made up of organic transistors on an ultra-thin polyimide film. The TFT thin-film technology is based on bottom-gate device architecture with both the gate dielectric layer of polyvinyl phenol and the pentacene organic semiconductor being processed from solution by spin coating. This architecture involves the use of standard lithographic techniques to pattern gold and thereby form gate electrodes and interconnects. The source-drain electrodes and second-level interconnects are provided by a second gold layer. The electrode plane of the display was formed from a polyester/indium tin oxide sheet.

5.6 Other New Technologies As consumer products become smaller and offer more services to the user, one frequent consequence is that they contain increasing numbers of physically smaller components. A typical example of this trend is the hearing aid where the emphasis is on providing a more powerful and efficient device which will improve the wearer’s quality of life. The Acuris P hearing aid from Siemens incorporates a moulded interconnect device (MID) made from Ticona’s Vectra E820i LDS liquid crystal polymer (LCP). This novel plastic permits complex, fine-line circuit patterns to be laser-etched and then plated. The MID itself, whose function is to connect the microphone module to other electronic components in the unit, is approximately 3 mm wide and 25 mm long. Vectra E820i LDS can be moulded into thin-walled parts and then processed by LDS to create the intricate circuitry required in hearing aids, sensors and other electronic components. LDS involves a triple stage process which initially involves the injection moulding of the LCP blank followed by the inscribing of a conductor track lay-out on the surface of the blank using a computer-controlled laser. Finally metal is electroplated on to the tracks to create a three-dimensional circuit board on the surface of the LCP. The LDS process is available from LPKF Laser & Electronics AG (Garbsen, Germany) which has an agreement with Ticona to modify Vectra LCP for three-dimensional MID. LPKF has also signed know-how and licensing agreements with BASF and Degussa. This process using Ticona’s new LCP grade enables three-dimensional circuit boards, featuring a high degree of design flexibility to be mass-produced. The ability to produce fine conductor patterns in almost any lay-out offers scope for better space utilisation as a way to assist the miniaturisation process. Other applications include mobile phone antenna modules as well as in the development and implementation of new mechatronic systems. Sensorics, also known as the electronic nose, represent another interesting technology where polymers are used because synthetic chemosensors can only detect a molecule when it is dissolved in a polymeric layer present in the sensor. The technology involves the use of a quartz crystal microbalance device to detect by volume and analyse surface waves on piezoelectric materials. Swelling detection on the basis of variations in conductivity also forms part of the technology. The role of polymers in this technology was discussed in an article by Banhegyi [3].

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The science of chemical sensors is being studied at Manchester University for the use and application of conducting polymers [4]. Derivatives of polyaniline, polythiophene, polypyrrole and poly(phenylene vinylene) doped with various ions have been investigated as chemical sensors for biosensors, volatile organic compounds, polymer field-effect gas-sensitive transistors and optical sensors based on electrochromic properties. The US Techni-Met Inc., has developed a process which may benefit some electronic applications where surface quality is paramount. The process involves the use of vacuum-sputtering technology and an acrylic monomer to lay down an acrylic polymer surface on film. The acrylic bonds to the film substrate by crosslinking and suitable films for the process include PET, PEN, PVC and polyimide. The company claims that its process confers superior water, oxygen and optical properties. Rapid prototyping is a growing products and services market. The first step is to design the component using CAD technology. The CAD data are then used by numerically controlled machine tools to produce the actual component from material in billet form. Polymers used for this process include acetal, ABS, PC, PP and PA. The choice of material will determine the characteristics of the finished product but, using the right materials, tolerances of +/- 0.05 mm are attainable. An alternative approach to rapid prototyping is to use the technology of stereolithography (SLA) which is capable of ± 0.1 mm per 100 mm. SLA involves the use of a beam of UV light to solidify the flow of liquid photopolymer resin which is controlled by instructions produced by a CAD system. The process builds up the prototype slice by slice. One of the inherent problems of the technology is that some models, especially if they have thin walls, may collapse or deform during the build up process. However the award-winning Manufacturing Engineering Centre (MEC) of Cardiff University’s School of Engineering claims to have found a software solution to this trapped volume problem. It is currently seeking worldwide patent protection for the process with a view to selling the patent, when awarded, to an established manufacturer of rapid prototyping SLA equipment. Previous MEC successes have included the introduction of colour to the rapid prototyping process. Suppliers of SLA material include DSM Somos whose NanoForm 15120 composite incorporates noncrystalline nanoparticle technology which is claimed to enhance performance properties including exceptionally high stiffness and heat resistance. Somos Precision HT 12920, an opaque grey version of its ProtoTherm 12120 high-temperature resistant material, has a level of stiffness similar to that of PC. Somos 9420 EP White is the opaque white version of Somos 9120 which is similar to PP. Other materials used include polyamide PA2200 powder. Another approach to rapid prototyping, also offered by Ogle Models & Prototyping (Letchworth, UK), is to use selective laser sintering. Starting with the computer generated CAD data, the process uses an argon laser to draw the part, one slice at a time, on to finely powdered PA12 which is then sintered (melted) so that the slices are built up into a solid component. The process is self-supporting to the extent that parts may be built within other parts with complex geometry. Ogle claims that this cannot done in any other way. Accuracy to +/- 0.2 mm is possible with this process. Raw materials for this process include PA, 30% glass-filled PA and 50% aluminium-filled PA known as alumide. The PA12 end product is claimed to have 70% to 80% of the strength of injection moulded products plus good surface finish and detail. The maximum part size offered is 330 mm x 330 mm x 610 mm. Moving potentially one step further from rapid prototyping to low volume production the vacuum casting process uses a master model, possibly derived from a SLA process, to make a silicon tool. The

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casting is carried out by pouring a wide range of PU resins into the tool via a vacuum chamber for de-gassing and the removal of the majority of air bubbles. Ogle can supply materials which mimic ABS, PP, PC and elastomers with a Shore hardness between 40A and 90A and with some materials being heat resistant up to 150 ºC. The size of Ogle’s in-house vacuum chambers extends to 830 mm x 460 mm x 500 mm and up to 25 replica PU parts per tool are possible. Subsequently, if required, a chrome finish of any colour can be applied by thermal vacuum metallisation. Not only are polymers being used for power storage but they are also being used for memory storage as demonstrated by researchers at Princeton University in the US in collaboration with HewlettPackard Laboratories. The inherently conductive polymer, PEDOT, is used to make a memory which is technically a hybrid because it contains a plastic film, a flexible foil substrate and some silicon in the form of PEDOT organic conducting polymer dots on the surface of a thin film inorganic silicon diode. The researchers have speculated that it could support up to 100 Mbits of memory. The power of PEDOT is its ability to be transformed from a conductor to an insulator by regulating the current which flows through it. The new technology system, which stores more data at less cost than expensive-to-build silicon chips, permits writing once only but allows reading many times. Other work on memories is being carried out by Nippon Telegraph & Telephone whose high capacity memory storage device combines a multilayered wave guide with thin film holography structured to produce a 100 layer postage stamp-sized one gigabyte memory module. Whereas plastic parts are frequently plated to give the appearance of metal this may be a cosmetic operation designed to give the illusion of greater mechanical strength. However, a new development from steel maker Corus’s Dutch technology centre is in a different league. The technique involves bonding steel with polymer in a one step operation to produce strong and flexible parts for computer equipment and consumer electronic devices, for example. Known as polymer injection forming the process can be carried out by existing injection moulding equipment and the technology is being licensed to interested component designers and manufacturers. The capabilities of the technique are illustrated by the example of a part containing 1 mm of polymer and 0.2 mm of steel. The cost would equate to that of a 1.8 mm thick part made entirely of polymer but the strength of the composite part would be equivalent to that of one 3.8 mm thick, made wholly from polymer! One of the benefits of the system is that it provides EMI shielding. Work on EMI shielding at the Technical University in Chemnitz, Germany has centred on co-injection technology to produce housings with a skincore structure. The process, when high optical quality components with a fibre free surface are required, uses non-conductive neat polymers for the outer skin and steel fibre-filled compounds for the core. If optical quality is not required, conductive polymers can be used for the outer skin with a neat polymer core. P-Wave is an advanced method of through-transmission infrared welding of sensitive plastic parts which enables an unprecedented range of engineering thermoplastics to be welded together. The range of engineering plastics which may be welded together using P-Wave technology includes clear, opaque and coloured parts and films. Another technology available to the component designer is film insert moulding (FIM). This enables complex moulded parts to be created in an efficient and economic manner as, for example, when

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displays require to be integrated into product housings. Autotype International supplies Autoflex HiForm and Autoflex XtraForm formable hardcoatings which may be applied to PC film. The company also produces a range of formable screen printable lacquers which can be selectively printed on to the first surface of the FIM film before forming. Industry analysts claim that future growth in the demand for conductive polymers will be driven by the fast-growing market for OLED displays rather than the flexible format. In 2005, Samsung introduced a 55 cm OLED prototype which the company claimed would be suitable for the viewing of HDTV. The technology of conductive polymers has developed to such an extent that formulations are now available which, it is claimed, will conduct electricity as well as some metals do. The most popular resins used in conductive polymers, accounting for over 75% of usage in compounds in 2003, are ABS, PVC, PC, PPE-based resins, PE and PP. ABS is the main choice because of its high impact strength. In 2005 Philips, which invests around 10% of its sales income on R&D, claimed a new research breakthrough with a polymer-based memory which is non-volatile, that is to say it will not lose data when the power supply is switched off. The technology involves the use of a FET in which the gate dielectric is composed of a polymer ferro-electric material. Applications include the ability to make low-cost RFID, a product which is being widely introduced into logistics and retail businesses with reported world production estimates of some 1.3 billion tags in 2005. The tags can cost as little as €0.23 and for logistics applications may be attached to pallets to monitor their progress through the distribution chain. For orders in excess of one million self-adhesive labels with built-in RFID inlay, Sato UK is reported to be quoting a unit price of 12.9p. One of the latest applications for the technology is in hospital where the system enables clinicians to access information about patients from the RFID enabled wristbands. These are fitted to patients when they are admitted to hospital. Clothing suppliers can now offer garments with a uniquely numbered RFID inlay embedded in the label of each individual garment. Some of the latest products to carry a RFID tag are the casino chips at new Wynn Casino in Las Vegas and tickets for the 2006 World Cup football matches in Germany! The retailer Walmart has adopted RFID technology in a big way. By January 2007 its 300 largest suppliers will participate in a trial and in 2006 the number of its supermarkets taking tagged goods will double from 500 to 1000. Mobile RFID readers will be deployed at the first 500 stores taking part in the trial where staff will be directed to boxes of products which need to be replenished. In another use of the technology, Walmart is moving ahead with a system to automate the production of advance shipping notices by arranging for the merchandise tags to generate them as they leave the warehouse. In the UK, Marks and Spencer has attached RFID tags to around four million reusable food trays - here it has discovered that the information on the tags can be read in five seconds rather than the thirty seconds needed to read the information in bar coded form. Consequently distribution vehicle turnround time can be cut and throughput and efficiency increased. However, suppliers are not necessarily enthusiastic if they have to invest to meet the needs of one customer, Marks and Spencer, whilst their other customers still have to adopt RFID technology! At the recent International Solid-State Circuits Conference ISSCC held in San Francisco in February 2006, Cantatore and co-workers from Philips presented their plastics electronics RFID tag which can be printed directly on to a plastics substrate along with its antenna [5]. Currently a silicon chip based

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system is used which necessitates a more complex assembly procedure. The new system is capable of transmitting multi-bit identification codes at the RFID tag industry standard frequency of 13.56 MHz. The information presented at the ISSCC is partially derived from the participation of Philips in the PoliTag project funded by the German Federal Ministry of Education and Research (BMBF). Philips has also benefited from its participation in the sixth European Framework Programme project, PolyApply. Philips also has a research project involving the low cost manufacture of this type of tag using reel-to-reel technology and in-line processing. This type of system could facilitate the cost-effective marking of individual packages rather than the marking of complete pallets which is currently considered to be the most viable option of using the technology, which is seen as a replacement for bar coding. The technique of low-cost RFID tag production entirely by screen printing, has been developed at Japan’s National Institute of Advanced Industrial Science and Technology. The method also eliminates the need for high temperature baking. One of the stumbling blocks to full use of reel-to-reel printing technology has been the production of the RFID antenna. However, Texas Instruments, which already produces a range of silicon RFID chips capable of over 1,000 write/erase cycles and two year data retention, can now deliver flexible Gen 2 antenna inlays directly printed on to a PET substrate 75 μm thick. XINK Laboratories, another supplier, can offer lexographically printed RFID antennae using a proprietary silver ink which cures at ambient temperature. The company’s materials are printable in a single pass on to a range of heat-sensitive substrates such as PET and paper as well as those used in pharmaceutical packaging for example. PolyIC directly prints the RFID circuitry on to standard polyester foil using organic semiconductors and insulators to build up the necessary transistors. The UK Ministry of Defence (MOD) has been using RFID technology in its Total Asset Visibility system since 2002. It is used to track military shipments around the world and the MOD is now planning to extend its use to combat zones. In early 2006 the UK government privatised a further stake in QinetiQ the company spun out of its military research organisation. The MOD had retained the secret projects and privatised those activities seen to have applications in the private sector. One of QinetiQ’s research projects has the objective of printing complete electronic circuits including both active and passive elements. The project has attracted both MOD and Department of Trade and Industry (DTI) funding, because if it is feasible, it could benefit both the consumer and defence electronics sectors. Previous research in this field has been targeted at high-volume, low cost applications whereas the new project is looking to develop materials which could be attached to clothing or containers for example. One aim is to develop additive, rather than etching, processes which would combine low manufacturing cost with short production runs. Another aim is to achieve size reduction and lower manufacturing cost. Technologies to be used include the deposition of conductive polymers to form the pixel elements of a TFT display and QinetiQ’s proven ability to print fine metal lines with a feature size of approximately 1 μm in order to build up thin film FET. Another interesting development from Philips, this time in conjunction with the University of Amsterdam, is a simple polymer-based electroluminescent device which can be switched between glowing red or green merely by reversing the current flow. The polymer used is a semi-conducting derivative of polyphenylene vinylene blended with a phosphorescent complex consisting of two

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ruthenium centres linked by a tetraphenylene bridge. The doped material is sandwiched between gold and indium tin oxide electrodes. The research was described in an article, Electroluminescent Device with Reversible Switching between Red and Green Emission, in the 2nd January 2003 issue of Nature (pages 54 – 57) by Steve Welter and Luisa De Cola of the University of Amsterdam, Klemens Brunner of Philips Research and Hans Hofstraat of Philips Research/ University of Amsterdam. Electroluminescent displays are made in Wales by Pelikon at its Cardiff plant where the company specialise in control panel displays. These thin plastic electroluminescent displays comprise a series of segments, each of which is a hidden membrane switch which is identified by an icon above the area of contact. Multi-function touch regions can be incorporated as well a capacitive touch on/off facility. Target markets include the white goods domestic appliance sector. In another application of electroluminescent technology, the Light Tape company produces light sources in the form of tape which, for example, is available in a 25 mm wide, 0.5 mm thick, format in lengths of up to 90 m with a power consumption of 0.004/cm2. Consequently, this 90 m tape will consume less energy than a 100 W incandescent light bulb. The tape is designed to be powered either by a 3 V to 12 V DC supply or variable AC whose frequency is adjustable between 200 Hz and 2000 Hz and which is fed by a 90 V-260 V power supply. The tape is made by sandwiching light emitting phosphors, which are activated by passing current through them, between two very thin electrical conduction plates, one of which is transparent with the other being opaque. The tape is available with an adhesive backing in various colours and widths for both indoor and outdoor applications and will provide flashing or steady state lighting. Experiments for the US Air Force showed that the tape lighting was visible from a distance of 8 km. Furthermore, the light from the tape was able to penetrate poor visibility conditions such as fog, haze, smoke and snow. The tape is flat and flexible with the ability to be wrapped round corners and attached to uneven surfaces. Phase separation micromoulding represents a new generic approach towards the microstructuring of a wide range of materials including block copolymers, conductive polymers and biodegradable polymers. The process, as described by a group of scientists from Twente University in the Netherlands, is based on the phase separation of a polymer solution in contact with a structured mould. The thermal shrinkage which occurs during phase separation is used to facilitate the release of a replica from the mould and can be used to make ceramic, carbon and metal microstructures from a polymeric or hybrid precursor by the inclusion of a post-processing step such as pyrolysis. Teijin has developed a new PC film with improved optical qualities to the extent that it was the only such film chosen for the cover layer of the next generation Blu-ray DVD. Currently made by the use of a film casting process but destined to transfer to a new extrusion process which will significantly reduce costs.

5.7 Recycling In 2001 only 6.3% of plastics in the UK were recycled. Current recycling levels are unavailable but the pressure is on to recycle more with recent prices being paid for recyclable plastics reported to be between £130/£150 per tonne for natural HDPE, £70/£90 per tonne for mixed plastics, £130/£170 per tonne for clear PET and £15/£25 for PVC.

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In 2005 Teijin completed the construction of a pilot plant, which utilises new technology, for the chemical decomposition of used PC resin to recover high-purity bisphenol-A and began preparations for commercial operations. The PC subsequently derived from polymerisation is of equivalent purity to that derived from petroleum. Teijin is well versed in recycling technology having already gained experience in PET recycling from its closed loop bottle-to-bottle technology. The process already permits the production of PET resin raw materials from used PET bottles. Teijin claims that the raw materials derived from its recycling processes are of comparable purity to those derived from petroleum. In addition to its PC recycling activities Teijin is also developing the technology to recycle PLA. Recyclable shape memory plastic alloys have been developed by the Japanese NEC Corporation which has made them from maize-derived polylactide. At a temperature of 60 ºC it will revert to its original shape after being deformed by heat or force. PU is another polymer which can be endowed with shape memory properties by introducing magnetic iron oxide nanoparticles, whose diameter is less than 50 nm, into the polymer during the extrusion process. Researchers at the German Institute of Polymers and the Institute of Polymer Research in Teltow near Berlin have discovered that the application of an alternating magnetic field to the modified polymer generates heat within the material and actuates the shape memory effect. It is possible to determine the amount of heat generated or magnetic field required by varying the proportion of nanoparticles to be embedded into the polymer. The initiation of the effect simply by applying a magnetic field, without the external application of heat, is seen by the researchers as a major benefit in sensitive locations where local heating could have adverse effects. In an another interesting application, the Japanese electronics group, NEC, is recycling fly ash from coal-fired power stations in the manufacture of flame-retardant PC resin. Not only does the new process reduce the manufacturing energy requirement by more than 20% but it also improves the flame resistance of the material without recourse to such flame retardants as halogens. Active Fasteners Ltd., the UK spin-off company from Brunel University, has developed a polymer technology for breaking down end-of-life electrical and electronic equipment. The company used shape memory polymers, typically ABS, PC and PET, which lose their mechanical strength when heated and which can be used as releasable fasteners. The polymers were partially melted to be reshaped and then altered again by freezing. The polymer would ‘remember’ the shape it took when it was partially melted and would try to regain it when it reached that temperature. The materials are dis-assembled by heating and are rotated in the mouth of a trommel which is a type of cylindrical sieve normally used in mining operations. Some polymers are far more difficult to recycle than other. In this category are fluorinated resins where the problem is the gas generated when the polymer thermally decomposes. However a joint venture between the two Japanese companies, Asahi Glass Co. Ltd. and Nittetsu Chemical Engineering Ltd., has developed the necessary technology to carry out recycling. The European Union is endeavouring to ensure that electronic and electrical equipment is designed and manufactured in such a way that when operated under its design conditions, it has a minimal effect on the environment during its life cycle. Mobile phones are a case in point with speakers at the GPEC 2004: Plastics – Helping Grow a Greener Environment Conference in Detroit, advocating the requirement for mobile phone materials to be continually circulated after their initial use rather than being considered only for reclaiming recycling or down-cycling into separate or low-grade materials and uses.

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It is conceivable that some manufacturers facing the need to design both screening and recycling capabilities into their products may revert to metal pressings for packaging rather than plastics, particularly if this is more cost effective.

5.8 Chemical Safety The importance of chemical safety is illustrated by Schecter, Papke, Tung, Staskal and Birnbaum [7]. The report stated that polybrominated diphenyl ether (PBDE) flame retardant chemicals had been found in food taken from the shelves of a supermarket in Dallas, Texas. The report also revealed that levels of contamination were higher in the US than those reported from similar studies carried out in other countries. The research goes on to suggest that a key source of contamination measured in people worldwide may result from polluted items in their individual diets. Other evidence of food contamination gave rise to the advice to eat not more than two portions of oily fish each week due to the likely presence of a mercury build-up in the flesh of such fish. More recently a report by Hites, Zhu and Hoh [8] was made about how the DP highly chlorinated flame retardant was detected and identified in ambient air, fish and sediment samples in the Great Lakes of the United States with concentrations having once reached 490 pg/cm3 concentration at the eastern site of Sturgeon Point, New York State.

5.9 Compliance with European RoHS and WEEE Directives The European Commission 2002/95/EC Directive on WEEE seeks to establish high recycling targets for certain categories but these figures are not feasible if several polymers are combined in the same product, because of the costs involved in dismantling. Consequently, it is unrealistic to expect significant recycling savings in the small components sector. The WEEE proposals, which involved separate collection and selective treatment of all components containing halogenated flame retardants were considered to be neither practical or economical because of increasing integration and miniaturisation in the electrical and electronic sector. The requirement to remove hazardous substances was originally part of the WEEE but was subsequently detached and established as a separate directive. It includes the requirement to phase out lead, mercury, cadmium, hexavalent chromium, halogenated flame retardants and other hazardous substances by January 1st 2008. There is also a requirement to phase out brominated flame retardants notably PBB and PBDE although deca-brominated diphenyl ether has been excluded from the ban. However, the European Commission will re-assess the status of deca-brominated diphenyl ether taking into account the conclusions of the ongoing EU risk assessment and it is said that the derogation is under legal review. Currently there are differences of opinion between the European Parliament and the European Commission. Plastics containing the banned compounds will be present in the waste stream for some years, thus inhibiting the recycling of plastic products currently in use. In the UK, GAMBICA, the trade association for instrumentation, control, automation and laboratory technology, has launched a not-for-profit company to operate the business to business compliance scheme under WEEE regulations. GAMBICA has also assembled a WEEE/RoHS Task Force involving over 30 member companies. This assists members to influence or monitor the development of

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the legislation. GAMBICA also works closely with and plays a leading role in its European sister organisation, ORGALIME. Although the target date for the UK implementation of the 2002/96/EC Directive on Waste Electrical and Electronic Equipment (WEEE) relating to electronic waste was Summer 2005, this was deferred following concerns expressed by businesses and stakeholders; the actual implementation date is now still under review. The directive stipulates that producers need to guarantee financing of treatment, recovery and recycling of collected materials which are grouped into 10 distinct categories. The term producer covers anyone who manufactures and sells electrical and electronic equipment under their own brand, anyone who resells equipment produced by other suppliers under their own brand plus anyone who imports or exports electrical and electronic equipment on a professional basis. UK government recycling policy has been criticised because its targets are based on collected tonnages thus encouraging local councils to shun plastics in favour of paper and green waste collection, thus, plastic bottle and container collection facilities are less frequently found. There is a market in the UK for recycled plastics but the recyclate is frequently sourced from mainland Europe. Plastics materials recovered in the UK may not always be used in the UK. There are also potential problems relating to the July 2006 implementation of the European RoHS 2002/95/EC directive with many OEM and CEM believed to be holding non-compliant inventory of components which will be virtually impossible to use legally after the implementation date. The cost of writing off such inventory could lead to the demise of those companies struggling to survive in an extremely competitive market. There are no cheap, easy ways to confirm compliance with the RoHS directive but one relatively simple test for suspect products is to use X-ray fluorescence spectroscopy which disrupts the electrons in the shell of the elements present in the sample. However, this technique can only detect surface or near surface material. It works by detecting the response of each element which generates X-rays at a unique set of energies, this permits the concentrations of the various elements to be measured. The next deadline comes in December 2006 with the need to achieve specified collection and recycling targets. To this end Christian Salvesen and Midex Reverse Technologies are offering UK businesses the opportunity to dispose of all types of redundant, surplus and unwanted electronics. The items will be packaged to be collected by vehicles from the Christian Salvesen distribution network which will deliver them to the nearest Midex site where facilities exist for assemblies to be stripped down, repaired, reused or ground and separated into constituent materials which can be recycled. Christian Salvesen possesses the requisite waste handling licences and its fleet of 550 drivers is accredited for hazardous transport. Types of plastic resins suitable for recycling include ABS, expanded polystyrene (EPS), HDPE, high-impact polystyrene (HIPS), PET, PP, PS and PVC. However, one of the problems currently being addressed in the move to extend plastics recycling is the requirement for a process to extract brominated flame retardants from waste plastics in order to leave an ‘acceptable’ level in the plastics destined to be recycled. This is because the ban on the use of certain brominated flame retardants in new appliances will mean that plastic recyclates containing them cannot be used by the electronics sector, other applications will have to be found.

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Consequently it seems strange that when a process is apparently available to solve this problem it is not being used. The process was developed by Matsushita Electric Industrial Company Ltd and is claimed to be capable of separating flame retardants from used plastics whilst maintaining the plastics’ original properties to enable them to be used in some new products. The process involves the crushing of the plastic parts and then heating them, at the relatively low temperatures of between 160 ºC and 200 ºC, until they become soft. A liquid solvent, which dissolves only the retardant is added, then the flame retardant is separated from the plastics. Novel kneading technology using countercurrent extraction is utilised in the process. It is claimed that brominated flame retardants, which normally generate brominated dioxins when incinerated at low temperatures, can be recovered using this process. In 2005 the UK specialist recycling, Sims Group commissioned a new line dedicated to the recycling of plastics sourced from its waste electrical/electronic and fridge recycling services. The group has a daunting task as it strives to clean and upgrade over 15,000 tonnes per year of plastics. Its initial product stream is PVC rich and accounts for around 5% of production. The second stream, again accounting for around 5% of production, is a mixture of PP and PE. The third and final stream is a styrene mix containing a variable mixture of HIPS and ABS whose content depends on the source of the plastics. The company is endeavouring to upgrade its processes to generate individual polymer streams. In France, Galloo Plastics, the Galloo Group’s recycling unit, is able to accept raw automotive shredder residue and derive from it finished plastic compounds such as black PP pellets which are supplied to automotive markets. One possible solution to the plastics recycling problem is the patented Advanced Molecular Agitation Technology (AMAT), anoxic pyrolytic process which has been designed to optimise chemical and physical processing at the molecular level. The UK company AMAT Ltd., has built up its technical expertise in the treatment of used tyres where its process can be used on all sizes of tyre from offroad to passenger types. AMAT has worked with the American Molecular Waste Technologies Inc. (MWT) company whose expertise in this field has been accumulated over twelve years. The MWT microwave waste reduction process is designed to reduce organic materials, that is, everything in the municipal waste stream apart from glass and metals. This is because microwaves have the unique ability to break down molecular bonds in hydrocarbon chains to basic carbon. The net result is an environmentally clean process, with virtually no emissions, whose output is carbon plus a light oil similar to diesel which results from the condensation of volatiles. Needless to say glass and metal, which account for around 12% of municipal waste, would have to be recycled separately. In the treatment of waste plastics, pyrolysis, which involves energy control via microwave modulation where both frequency and wavelength change, is conducted in a very low oxygen atmosphere to prevent hydrocarbon combustion and subsequent explosion hazards. Initially, in order to obtain clean burn conditions, the mixed plastics waste has to be separated into non-toxics (PE and PET) and toxics (PVC and PU) because the latter materials can give rise to halogenated polycyclics and cyanide emissions. The carbon black type residue may be offered as a filler grade of carbon black for use in plastics masterbatching. The gas given off could contain a sufficient non-condensable hydrocarbon fraction to enable it to be used in energy generation. The non-hydrocarbon emissions would be a mixture of containable oxides of carbon along with hydrochloric acid and ammonia.

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Gas is the end-product of another process developed by NKK in Japan. In this application the principle of convergent shock waves is used to manufacture hydrogen from steam vapour, with a temperature of around 200 ºC, in conjunction with such waste as waste plastics with their hydrogen and hydrocarbon content. Potential applications for the hydrogen produced include power generation and fuel-cell powered vehicles. One of the current obstacles to the greater use of hydrogen is the storage problem. However a researcher at the University of California in Los Angeles, Omar Yaghi, is investigating metal organic frameworks (MOF) and claims to have found one which can absorb hydrogen to the level of 7.5% by weight, albeit at low temperatures. The MOF are said to have a scaffolding type construction with linked rods forming pores of different sizes. The hydrogen is stored by adsorption on to the rod components of the structure. The Victor Company of Japan, in collaboration with the National Institute of Advanced Industrial Technology and Clean Japan Centre (CJC), is developing a process to recover high-purity bisphenol A from waste optical disks, typically CD, CD-ROM and DVD. The new process decomposes PC resin at around 200 ºC in a nitrogen atmosphere under 2 MPa pressure, using sodium carbonate in cyclohexanol as a catalyst. In CJC simulations it was shown that was possible to secure an 80% yield of 99.9% pure bisphenol A. The National Weights and Measures Laboratory has been appointed by the DTI to police UK implementation of RoHS legislation and is in the process of publishing guidelines setting out the nature of the documentation needed to confirm due diligence. In particular, manufacturers are required to ensure that their products, as well as their components and sub-assemblies, comply with the regulations by the relevant date in order to be placed on the EU single market. The regulations relate to eight distinct categories of equipment including, for example, consumer electronics which includes such items as television sets, audio equipment, video recorders and digital cameras. Products must not contain any of the following substances in excess of the prescribed levels of 0.01% for cadmium and 0.10% for lead, mercury, hexavalent chromium, PBB and PBDE. Because of concerns over safety and reliability Categories 8 (medical devices) and 9 (monitoring and control instruments) were excluded from the RoHS Directive when it was originally adopted. However, ERA Technology has now been contracted by the European Commission to carry out a review of the Directive to determine whether these two categories can now be included within its scope. The results of this review will be used by the European Commission to prepare a proposal to the European Parliament and the Council which will act together to amend the Directive. One of the consequences of the implementation of RoHS legislation is the need for higher temperature tolerant polymers in components with solder connections. This is necessary because the new generation of RoHS compliant solders has a higher melt temperature than that of the former lead-based types. Polymer manufacturers have responded to the challenge and the following sample specifications show what is now available. For example the DuPont ThermX polyester tolerates high temperatures and is based on poly(cyclohexylene-dimethylene terephthlate) chemistry. It has the chemical resistance, dimensional stability and processability of such polyesters as PET and PBT but with a melting point of 285 ºC compared with PET (255 ºC) and PBT (225 ºC). DuPont claims that ThermX complements its other very high thermally capable Zenite LCP and Zytel HTN (high temperature Nylon) resins in applications which call for higher thermal capabilities than those of PBT, PET and PA66. ThermX,

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which is resistant to automotive fluids and chemicals used for the cleaning of PCB, is chemically similar to Crastin PBT and Rynite PET. The GE LNP Engineering Plastics subsidiary offers THERMOCOMP HT Solder UF-1006 and THERMOCOMP HT Solder ZF-1006 compounds which comprise a matrix of resin blends containing 30% glass. The former compound is based on PPA resin whereas the latter uses a matrix of modifiedpolyphenylene ether. Both these grades are claimed to offer high distortion temperatures of over 260 ºC, excellent dimensional stability and excellent flame retardancy. LNP also manufactures Starflam Eco-Fr compounds which are based on glass-fibre reinforced PPA coupled with ECO friendly flame retardant technology.

5.10 Nanotechnology Nanotechnology is extending its influence into many areas of electronics activity some of which are discussed next. According to the US Business Communications research organisation, the world market for polymer nanocomposites, is growing at an average annual rate of 18.4% and is expected to exceed US$211 million in value by 2008 with the UK reported to be a global leader in commercialising nanotechnology. The UK Government’s Science and Technology Minister, Lord Sainsbury, speaking in late 2005, valued the UK’s current annual turnover for all micro and nanotechnologies at £11 billion adding that it supported around 20,000 jobs. The BSI Director, Mike Low stated that the global nanotechnology market was expected to reach £16.7 billion ($29 billion) by 2008. In 2004 the EU provided funding of £1.7 billion ($3 billion) for nano-related projects. This represented almost one-third of the £5.7 billion ($10 billion) sum spent globally by public sector and private organisations. The importance of nanotechnology is now recognised to the extent that the BSI hosted the inaugural meeting of a technical committee for nanotechnologies in November 2005. This was designed to give nanotechnologists a uniform language and process since it is believed that standardisation will encourage safer and faster product development. Simultaneously it should lead to the development of interoperable products. In Japan, Teijin has structured its nanotechnology activities into three separate strands. In one area it studies molecular-level polymer engineering and the structural control of material properties using selforganisation. In the second, it is working on nano-order polymer layering and other nanoprocessing technologies, whilst the third area is focussed on nanocomposite technologies which use the controlled dispersion of nano-order materials into polymers to produce high performance compounds. Teijin’s 2005 Annual Report states that current nanotechnology businesses include PCB and highdensity memories. In the development stage or preparation for commercialisation category come new optical films, new substrate materials, PC recycling technologies, photodegradable and biodegradable films and battery materials together with nanocomposites and increased production of both carbon and aramid fibres. Projects at the research stage include new carbon fibres, nanocomposite aramid fibres and PEN film, flexible solar battery substrates, organic electroluminescence and paper displays. Carbon nanotubes (CNT) are key elements of nanotechnology. Those produced by Bayer as Baytubes and have a maximum mean diameter of 50 nm and are 10,000 times thinner than a human hair.

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They are multi-walled tubes comprising up to 15 graphite layers and are, chemically, identical to the lead in a pencil. Bayer claims to have achieved consistent material purity of over 99% whilst simultaneously significantly reducing manufacturing costs. In the UK, researchers at Cambridge University have devised a method of growing vertical carbon nanotubes on a flexible plastic substrate which gives scope for further research into potential applications especially where flexibility is a key element of the product design. At Sheffield University the research project involves the dispersion of nano-sized droplets of PEDOT (or other conducting polymers) into a polyethylene oxide polymer electrolyte matrix. Together with a suitable redox couple, where oxidation and reduction are considered together as complementary processes, it is possible to produce efficient, switchable windows for microwaves. A press release from Bayer in November 2005 explains that the nanotubes in their black powder form will withstand mechanical loads 60 times better than steel whilst being only one-sixth of the weight of steel. The carbon atoms in the wall of the tube form a uniform hexagonal lattice which is comparable to a honeycomb and which is the basis for the tube’s very high mechanical strength. If the edges of the hexagon are aligned parallel to the axis of the cylindrical tube, as in single walled nanotubes, the material will conduct electricity far better than copper. However, if the edges of the hexagon are aligned vertically the material will act as a semiconductor. Consequently, the CNT are ideally suited to be electrodes and high frequency transistors. They are also being selected for a wide range of other applications. For example, in Japan, Mitsui Chemicals has launched a new grade of dust-reducing, antistatic nanocomposite, Aurum CNT, which is a combination of thermoplastic polyimide and carbon nanotube. It was developed jointly with Hyperion Catalysis and is targeted at applications such as processing jigs for the manufacture of semiconductors. The electrical conductivity of the new material may be controlled, an option not possible with conventional antistatic materials. Mitsui Chemicals is the sole manufacturer of Aurum, a thermoplastic polyimide with a Tg of 250 ºC and good resistance against plasma and other types of radiation. Unlike other conventional polyimides which are processed by a casting method, Aurum may be moulded by extrusion. The Tokyo University of Technology reports another CNT application in which they are dispersed with rubber materials in order to make them electrically conductive. The materials produced exhibit excellent volume resistivity. Potential applications include electrode materials, EMI shielding materials and antistatic agents. In the US, Hyperion Catalysis International has modified fluoropolymers with CNT to make them conductive. One of the problems encountered as transistors get smaller and increasingly tightly packed is that of heat dispersion where it is accepted that carbon nanotubes can carry the heat away, the question being where? In its attempts to find a solution to the problem, Canon has investigated the removal of the base silicon from a manufactured wafer and transferring it on to a variety of materials including plastics, where flexible and low cost chips are involved, to diamond which is seen as a good but expensive heat sink. Areas for commercial exploitation of electronic CNT nanotechnology include backlighting, field emission displays together with various films using nanomaterials.

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Use of nanotechnology is also found in thermosets where a new generation of nanoscale silicone and core-shell particles is dramatically modifying the properties of heat resistant thermosets. Even small additions of the particles can significantly increase the fracture toughness and impact strength of reactive resin and other plastics. Nanotechnology is also entering the world of magnetic storage where a research group at John Hopkins University (Baltimore, MD, USA) is investigating the use of nanorings. These are produced by the deposition of a layer of PS nanospheres on to a substrate which is sputtered on to a layer of cobalt. An ion beam is then used to erode the unprotected cobalt. By tilting the substrate to between 10 and 14 degrees during the erosion process asymmetric rings are formed over which a thin gold or copper layer is sputtered to prevent oxidation. The bistable rings have two steady states according to whether the magnetic flow is in a clockwise or anticlockwise direction. These ‘vortex’ states can be manipulated predictably but the technology is still at the development stage. Yet another development, at the University of Toronto in Canada, is based on the discovery of the first plastic material to absorb infra red light. This achievement came about as a result of doping a polymer with nanometre-sized semiconductor particles that were tuned to absorb in the infra red region of the frequency spectrum. Not only had the research team discovered what was claimed to be the world’s first infra red detector which could be painted but also the world’s first infra red photovoltaic detector. The researchers believe that, by combining infra red and visible photovoltaic processes, it could be possible to reduce the cost of solar energy since the current 6% best efficiency figure for plastic solar cells might even be raised to 30%. In the USA the National Institute of Science and Technology has discovered that the dispersion of a very small quantity of carbon nanotubes into PP greatly reduces the flammability of the polymer. An alternative approach to flame resistance is offered by the US PolyOne Corporation which supplies a range of nanoclay-based additives. These Nanoblend additives are claimed to be able to boost the fire resistance of flame-retardant PE and PP. The use of nanotechnology in transistor technology is being investigated at the Hahn-Meitner Institute (Berlin, Germany) where a new process allows semiconductor nanowires to grow vertically inside a plastic film. The semiconductor nanowires act as transistor channels and researchers at the institute are experimenting with different semiconductor materials in order to try and boost the polymer transistors’ performance. An alternative approach to the manufacture of plastic transistors has been adopted in the US by Lucent Technologies who claim to have established a method of stamping out units ranging from 150 nm to 250 nm long, these are said to be about twice the size of conventional commercial silicon transistors. Research at Cornell University in the US has been targeted at the development of PC-based nanocomposites for use as mobile phone casings with enhanced impact resistance. The research team has developed nanoclay treatments which give rise to good dispersion in the PC matrix and resist decomposition at the relatively high processing temperature of the engineering plastic. This significantly reduces or eliminates discoloration of the plastic when compared with existing treated nanoclay whilst simultaneously boosting its physical properties. Cornell researchers go on to claim that toughness is increased by 30% compared to those conventional PC and PC nanocomposites which were based on clay technology used elsewhere at the time of the research.

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References 1.

UL 94, Tests for Flammability of Plastic Materials for Parts in Devices and Appliances, 2003.

2.

J.E. Schindall, J.G. Kassakian and R. Signorelli in the Proceedings of the 15th International Seminar on Double Layer Capacitors and Hybrid Energy Storage Devices, 2005, Deerfield Beach, FL, USA.

3.

G. Banhegyi, Muanyag es Gumi, 2004, 41, 4, 153.

4.

K.C. Persaud, Materials Today, 2005, 8, 4, 38.

5.

E. Cantatore, T. Geuns, A. Grujthuijsen, G. Gelinck, S. Drews and D. de Leeuw in Proceedings of the International Solid-State Circuits Conference ISSCC, 2006, San Francisco, CA, USA, Session 15.1.

6.

S. Welter, L. De Cola, K. Brunner and H. Hofsraat, Nature, 2003, 421, 6918, 54.

7.

A. Schecter, O. Papke, K-C Tung, D. Staskal and L. Birnbaum, Environmental Science and Technology, 2004, 38, 20, 5306.

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R.A Hites, L. Zhu and E. Hoh, Environmental Science and Technology, 2004, 40, 4, 1184.

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Arkema See profile for Total SA www.arkema.com

Basell BV Hoeksteen 66 PO Box 625 2130 AP Hoofddorp Netherlands www.basell.com Basell was established in 2000 as a 50:50 joint venture of BASF and Shell designed to consolidate their global polyolefins businesses including their Elenac, Montell and Targor subsidiaries. Basell reported total sales of €6.7 billion in 2004 when it had 6,600 employees with operations in 21 countries. Sales activities extended to 120 countries. In 2005, Access Industries, the American industrial holding company, announced that it had bought Basell from its BASF and Shell parents for a total cost of €4.4 billion. Basell is the world’s largest PP producer. It is also a major supplier of catalysts and PE, and is Europe’s leading producer. Furthermore it is a global leader in the development and licensing of PP and PE processes.

BASF AG Carl-Bosch Strasse 38 D-67056 Ludwigshafen Germany www.basf.com BASF is one of the world’s leading chemical companies with around 82,000 employees worldwide and reported total 2004 sales of €37.5 billion, up 12% from the figure of €33.4 billion recorded in 2003. Operating income earnings before interest and taxes (EBIT) rose by 82.7% to €4.9 billion in 2004 from €2.7 billion in 2003. BASF has production facilities in 41 countries and maintains contact with customers in more than 170 nations.

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Sales in the plastics segment, which accounts for 28.1% of the business rose to €10.5 billion in 2004 with operating profits up to €669 million. The BASF product range comprises styrenics including Terluran ABS, LuranS-acrylate styrene acrylonitrile (ASA), PS and expandable polystyrene (Styropor/Neopor) together with speciality foams such as Styrodur XPS crosslinked polystyrene. The Performance Polymers range includes Ultradur PBT thermoplastic polyester, Ultraform POM acetals, Ultramid PA, Ultrason PSU polysulfone and Ultrason PES polyethersulfone. Additionally BASF produces a range of PU systems and has purchased the Swedish polyurethane business of Systemhaus Lagomat. Other acquisitions include the 2003 purchase of Honeywell’s engineering plastics business which establishes BASF as the second largest Nylon 6 producer in North America. BASF also purchased the engineering plastics business of Leuna-Miramid GmbH. However, following the sale of its stake in Basell the company has withdrawn from some product areas. The Elastogran GmbH subsidiary of BASF is a specialist producer of PU which in its soft, plasticiserfree formulation is a popular material for the handles of electric power tools, laptop computers and mobile phones, because, whilst remaining tough, it is relatively soft to the touch. BASF is very active in Asian markets and established a joint venture, Toray BASF PBT Resin Sdn. Bhd., with the Japanese Toray company whose activities include the construction of a PBT production plant in Kuantan, Malaysia, for potential customers in the automotive, electrical and electronics sectors. BASF invests heavily in R&D, especially into nanotechnology, where results include the launch of Ultradur PBT High Speed where the addition of nanomaterials has resulted in the product’s improved flow properties to the extent that the time needed to manufacture components has fallen by up to 30% for customers in the electronics and automotive sectors. There are also energy saving benefits because of the lower processing temperatures and pressures. BASF has also developed Ecovio, its first biodegradable plastic, which is 45% PLA, the other component of the compound being BASF’s existing Ecoflex biodegradable plastic which is derived from petrochemicals. Applications include plastic films and mobile phone housings. The material will decompose in a matter of weeks and its PLA content is largely carbon dioxide neutral when composted. BASF has invested in E-commerce to improve its procurement processes and owns a stake in cc-hubwoo. This is one of the world’s busiest marketplaces with more than 20 million articles, over 800 suppliers and more than one million completed transactions in 2004. E-commerce is also a sales tool accounting for plastics segment sales of more than €2 billion in 2004. In some business areas this represented up to 80% of sales!

Bayer AG D-51368 Leverkusen Germany www.bayer.com According to Bayer AG Management Board Chairman, Werner Wenning, 2005 was one of the most successful years in the company’s history. Net sales of Bayer MaterialScience, which represents Bayer’s largest business sector, were €10.695 billion, up from €8.597 billion in 2004 with an EBIT of €1.369

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billion up from €641 million in 2004. In 2005 net sales of Bayer MaterialScience accounted for 39% of 2005 group sales of €27.383 billion. The sector’s leading polymer products are PC and PU. Bayer and DuPont have established a joint manufacturing venture to produce PBT. Electronic applications for Bayer’s Desmopan thermoplastic PU film include a solar cell encapsulation process. In November 2005, Bayer revealed that its new manufacturing process for the innovative carbon nanotubes had reduced their manufacturing cost. Bayer has also introduced formable PC films which incorporate EMI/RFI shielding. This is obtained by printing them with conductive ink or by dispersing the ink into the cap layer of the sheet. Other innovations include the smart surface technology process which Bayer has developed in conjunction with Lumitec of Switzerland and which involves the production of flat light sources. These electroluminescent elements, whose ‘smart’ outer skin is a printed Makrofol/Bayfol (PC/PC + PBT blend), do not dissipate any heat and are maintenance free. The light is produced in the multilayer printed system beneath the skin and shines through it. The system itself is an electrode, Baytron P for example, with a counter-electrode underneath The two electrodes are separated by a non-conductor. The mouldings used are produced by a single step process and require minimal assembly work. Bayer has recently invested €24.5 million in a start-up company to produce electroluminescent films. The strategy of Bayer is to base its growth strategy on innovation and it reported that around 20% of the revenues of Bayer MaterialScience resulted from new products and applications introduced during the course of the past five years. The Bayer Group places an emphasis on R&D on which it plans to spend around €1.9 billion in 2006. Underlining its commitment to PC of which it is, along with General Electric, one of the world’s leading manufacturers, Bayer has constructed a world-scale Makrolon production plant at Caojing in China designed to come on stream in 2006. Bayer plans to invest around US$1.8 billion in worldscale polymer facilities in the period up to 2009. Bayer subsidiaries include the HC Starck Group which supplies parts and materials to the electronics and other sectors. The HC Starck Group has 14 sites in Europe, the USA and Asia. It has around 3,400 employees worldwide and reported 2004 sales of more than €703 million.

Borealis A/S Parallelvej 16 DK-2800 Kongens Lyngby Denmark www.borealisgroup.com Borealis, now 65% owned by the International Petroleum Investment Company of Abu Dhabi with the major Austrian oil and gas company OMV owning the remaining 35%, is a leading manufacturer of polyolefins, notably PE and PP. The Borealis group net sales in 2005 were €4.814 billion, up from €4.628 billion in 2004, a rise of 4.0% although operating profits fell by 15.1% to €236 million in 2005 from €278 million in 2004.

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The workforce fell from 4,547 employees to 4,536 employees. The company suffered from reduced overall demand in Europe for polyolefins and its problems were exacerbated by high oil prices. New production capacity in Central Europe and Scandinavia came on stream in 2005 with the opening of the new 350,000 tonnes per year Borstar PE production plant at Schwechat in Austria and the 90,000 tonnes per year capacity expansion to the existing Borstar PP production plant which raises its potential output to 300,000 tonnes per year. The expansion of production at Schwechat represents an investment of €200 million and the new technology employed has resulted in potential energy savings of up to 7% per tonne of production output. PP production capacity has also been raised in Norway where the Noretyl joint venture with Hydro Polymers has increased from 125,000 tonnes to 175,000 tonnes per year. In Abu Dhabi, the Borouge joint venture with the Abu Dhabi National Oil Company has increased its Borstar PE production capacity to more than 600,000 tonnes per year. The key growth sectors for Borealis are in advanced packaging, automotive, energy and communication, cables plus piping systems. Borealis has a joint marketing agreement with the US Huntsman Corporation to provide customers, especially in the automotive and appliance sectors, with flexibility in sourcing via a global marketing network. Borealis also supplies polymers to mobile phone handset manufacturers.

BP plc 1 St. James’s Square London SW1Y 4PD www.bp.com The petrochemicals business of BP reported a loss of $900 million in 2004 and since 2005 the olefins and derivatives business has been operating as a standalone business within the BP group with a view to its possible disposal. At the end of 2004 Solvay exercised its option to sell its interests in BP Solvay Polyethylene Europe and BP Solvay Polyethylene North America to BP. The $9 billion sale of BP’s Innovene petrochemicals business in December 2005 was made to Ineos which then became Britain’s second largest chemical company with 15,500 employees in fourteen countries.

CDT Limited Building 2020 Cambourne Business Park Cambridgeshire CB3 6DW www.cdtltd.co.uk Founded as Cambridge Design Technology in 1992 by Cambridge University as a result of pioneering work into PLED by the Cavendish Laboratory, the company has grown and its latest full year results

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for 2004 show total revenues of $13.3 million, a 24% increase over the previous year. However, if the sales of the 50% owned US ink jet printing equipment subsidiary are excluded, the rise in revenue was 65%. CDT is having patent protection problems in the US where the Universal Display Corporation (UDC) has been granted a patent which could affect CDT’s American operations. According to press reports the patented technology relates to the ability to use ink-jet printing technology to produce OLED. UDC uses small molecular materials whereas CDT technology is based on the use of polymeric emissive materials. CDT’s financial results for the third quarter of 2005 were revenues of $6.6 million, up from $1.6 million in 2004. The quarter’s gross profit was $2.9 million up from $0.9 million in the comparable quarter of 2004. Subsequently, in December 2005, CDT used a private placement of shares and warrants to raise further capital of $17.5 million. In 2005 CDT established a Joint Venture company, Sumation, with the Japanese Sumitomo company. Sumation, which started trading in mid-November 2005, supplies polymers and formulated inks for use in both development and commercial P-OLED display and lighting applications. It has a Tokyo HQ with research and development teams in both Japan and the UK. Production of polyfluorene and other polymer materials has been subcontracted to Sumitomo Chemical’s Osaka plant. Earlier in 2005 Sumitomo had acquired the Lumation business, which was operating in the same sector, from the Dow Chemical Company. Sumitomo Chemical’s partnership with Seiko Epson has resulted in the first super bright OLED-based print head which, when used in printers, is capable of delivering results equal to or superior in quality to those from a laser printer. Other collaborative developments have been with Toppan Printing of Japan where the project has involved the construction of a billion yen pilot line to investigate alternative printing methods for the manufacture of PLED displays. CDT’s other partners include Bayer’s HC Starck subsidiary, Avecia’s Covion subsidiary which was acquired for €50 million in cash, by the German Merck company in early 2005. Merck KGaA, the world’s leading supplier of liquid crystals for LCD displays, had previously acquired the Lumitec OLED R&D project from the German Schott AG company. Simultaneously, Merck acquired Avecia’s Manchester-based polymer electronics research business. Merck also has its own polymer electronics R&D laboratory at Chilworth in the UK.

Degussa AG Bennigsenplatz 1 D-40474 Dusseldorf Germany www.degussa.com Degussa, whose activities include the manufacture of high performance polymers, is in the process of becoming a wholly-owned subsidiary of RAG, a German conglomerate which claims to be the world’s leading speciality chemicals company and the third largest chemicals company in Germany. RAG, which is based in Essen, has total annual sales revenues of around €22 billion and employs around 100,000 people worldwide. It is a leading coal producer, Germany’s fifth largest energy company and is also one of the largest residential real estate companies and land developers in Germany.

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Dow Europe GmbH Bachtobelstrasse 3 CH-8810 Horgen Switzerland www.dow.com Based in Midland, Michigan, USA and founded in 1897, Dow Europe’s Dow Chemical Company parent reported record financial results in 2005. Sales rose by 15% to $46.3 billion with net income up from $2.797 billion in 2004 to $4.515 billion in 2005, an increase of 61.4%. The company employs 42,000 people and serves customers in 170 countries. Total sales of the performance plastics segment rose from $6.667 billion in 2004 to $7.713 billion in 2005 with EBIT and minority interests up from $1.048 billion in 2004 to $2.467 billion in 2005. The plastics segment’s sales rose from $10.041 billion in 2004 to $11.815 billion in 2005 with EBIT and minority interests up from $1.725 billion in 2004 to $2.405 billion in 2005. Dow Plastics is a leading worldwide supplier of PE and PS. However its Questra syndiotactic polystyrene engineering plastic was withdrawn from the market after failing to secure the anticipated market penetration. The 36,000 tonnes per year production facility at Schopau in Germany was closed in mid-2005. Dow’s Emerge ABS 1500 resin has been specifically designed for the manufacture of chip carrying ‘smart cards’. In the Asia Pacific region Dow’s epoxy products and intermediates segment achieved healthy sales of laminates for flat panel television displays. In May 2005 Dow sold its Lumation LEP business to the Japanese Sumitomo Chemical Company Limited which is already engaged in this market activity and which will use its acquisition to broaden its product range. In December 2005 Dow, via its wholly-owned Union Carbide Corporation subsidiary sold its 50% holding in UOP LLC, a leading international process technology company, to Honeywell Specialty Materials whose interests include electronic materials. Other Dow disposals include the $92 million sale, to Ashland Composite Polymers, of the DERAKANE epoxy vinyl ester business whose products are used in fibre reinforced plastics and whose annual resin sales were around $70 million. Acquisitions include the Engage polyolefin elastomers, Nordel EPDM and Tyrin chlorinated polyethylene businesses from the former DuPont Dow Elastomers joint venture.

DSM Engineering Plastics BV Postbus 43 6130 AA Sittard The Netherlands www.dsm.com DSM Engineering Plastics is a Business Group within the performance materials cluster of DSM whose other members comprise DSM Coating Resins, DSM Composite Resins and DSM Elastomers. The

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Business Group has around 1300 employees and reported 2004 sales of €624 million and is one of the world’s leading suppliers of engineering thermoplastics with a broad portfolio of high performance products. In 2004, the DSM group, whose headquarters are at Heerlen in the Netherlands, employed 24,180 people (7,529 in the Netherlands) at year end at more than 270 offices and production sites in 49 countries with reported 2004 net sales of €7.7 billion and net profits of €262 million. The products of DSM Engineering Plastics are manufactured in the Netherlands, USA, Canada, Japan, China, India, Belgium and Germany. In 2002 DSM Petrochemicals was sold to SABIC of Saudi Arabia. DSM Engineering Plastics offers 70% of all the thermoplastic materials used in electronics and electrical applications. The grades specifically offered for these applications are UL 94 certified and take this industry’s stringent flammability requirements into account. The Group’s major brands include Akulon halogen-free, hybrid reinforced PA6 polyamides, Arnite thermoplastic polyesters Arnitel TPE copolyester elastomers, Stanyl PA46 high temperature polyamides and Xantar PC. Stanyl High Flow grades are intended for electrical and electronic applications because the high flow rates enable electronic parts with thin wall thicknesses to be produced. DSM Engineering Plastics also participates in the Omnexus E-marketplace trading venture. At the end of 2004, DSM Engineering Plastics had sold several of its speciality polymer ranges to the US Techmer Lehvoss Compounds, LLC. These included Electrafil conductive polymers and PlasLube lubricated thermoplastics. A year later, in December 2005, DSM announced the sale of another business - the North American PP business, including the Canadian compound production facility at Stoney Creek in Ontario, is to be sold to Fiberfil Engineered Plastics Inc.

DuPont (UK) Limited Maylands Avenue Hemel Hempstead Hertfordshire HP2 7DP www.dupont.com DuPont, based in Wilmington, Delaware, USA, reported worldwide net sales of $26.639 billion in 2005, down from $27.340 billion in 2004. The group’s sales were affected by the business impact of the hurricanes in the southern US states. However, net income in 2005 was $2.03 billion, up from $1.78 billion in 2004. Founded in 1802, the group now operates in more than 70 countries worldwide. In recent years the company has paid special attention to the Russian plastics market which was growing, on average by 15% per year, between 2003 and 2004. DuPont’s own sales into the market have shown increasing double digit annual growth rates in recent years. The group’s plastics activities are mainly concentrated in the electronic and communications technologies segment and the performance materials segment. The former segment reported net sales of $3.506 billion in 2005, up from $3.279 billion in 2004. The corresponding pre-tax operating income was $532 million in 2005, up from $192 million in 2004. The performance materials segment reported net sales of $6.750 billion in 2005, up from $6.633 billion in 2004. The corresponding pre-tax operating income was $523 million in 2005, up from $295 million in 2004. The electronic and communications technologies segment introduced 218 new products during 2005 including new fluoropolymer films for photovoltaic and fuel cell applications. R&D activity

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resulted in the performance materials segment reporting 184 new products in 2005 including new compounds for improved processing. Automotive and electrical/electronics industries are the largest markets for engineering polymers which include Crastin PBT polyesters, Hytrel thermoplastic polyester elastomers, Rynite PET, hightemperature Thermx PCT (polycyclohexylene dimethyl terephthalate), Tribon composites and Tynex filaments, Vespel polyimide parts and shapes, Zenite liquid crystal polymers and Zytel PA resins. In July 2005, DuPont launched the DuPont Vespel SP-202 composition whose properties include the prevention of static charge build-up. Other products include Delrin acetal resins, engineering thermoplastic vulcanisates, Minlon mineral reinforced PA resins and Teflon PTFE fluoropolymer resins. The reported strategy of DuPont is to derive 25% of its revenues from non-depletable resources by 2010. To this end it is reported to have switched production of a key polymer feedstock from a petrochemical to a maize-based process. In the case of Sorona (polytrimethylene terephthalate), the maize-based version is claimed to have environmental advantages over its petrochemical counterpart because the manufacturing process uses less energy, reduces emissions and employs renewable resources. In January 2005 the Dow Chemical Company elected to exercise its option to acquire certain assets relating to ethylene and chlorinated elastomers, including assets of the Engage polyolefin elastomers, Nordel EPDM and Tyrin chlorinated polyethylene businesses, from the 50:50 joint venture, DuPont Dow Elastomers LLC (DDE). Following the exercise of this option DuPont paid Dow $87 million for its remaining equity interest in DDE, which has now been renamed and has become a whollyowned subsidiary of DuPont. Previously DDE had annual sales of around $1.2 billion and were a leading global supplier of chloroelastomers, ethylene elastomers and fluorinated elastomers. The products of the former DDE business now include Hypalon chlorosulfonated polyethylene, Kalrez perfluorolastomer parts, Neoprene polychloroprene rubber and Viton fluoroelastomers. Other DuPont purchases include the acquisition of parts of Eastman Chemical Company’s highperformance crystalline plastics business by DuPont Engineering Polymers. However, the acquisition, which added Titan LCP, Thermx PCT and Thermx EG reinforced PET resins to DuPont’s product portfolio, was confined to technology rights and other business intellectual property. No transfer of physical assets or employees was involved. The DuPont Teijin Films joint venture, with Teijin of Japan, specialises in films and related products for electrical and electronic applications as well as for advanced magnetic media photographic systems and industrial packaging. Brands include Melinex and Mylar polyester films, Teijin Tetoron PET and Teonex and Kalodex PEN film together with Cronar polyester photographic base film. Toray-DuPont Co. Ltd is a 50:50 joint venture between the Tokyo-based Japanese Toray Industries Inc., and DuPont KK, Du Pont’s wholly-owned Japanese subsidiary. Toray-DuPont has been producing Kapton polyimide film for flexible printed circuit applications in the Asian Pacific region since 1985. In November 2005, DuPont Electronic Technologies announced plans for the joint venture to invest around $95 million in a new Japanese facility, alongside the existing Tokai City plant, which would result in a 25% increase in film manufacturing capacity when it opens in mid-2007. Applications for the film extend from mobile phones and personal computers to flat panel displays and integrated circuit packaging.

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DuPont’s nanotechnology activities include the development of a polyaniline containing singlewalled carbon nanotubes to be used in a laser ablation dry printing process to produce plastic transistors. DuPont Fluoroproducts have more than 30 years of fuel cell development experience. The company dispersion-casts or extrudes its Nafion brand of perfluorosulfonic acid polymer/PTFE copolymer membranes.

EMS-Chemie (UK) Limited Darfin House Priestley Court Staffordshire Technology Park Stafford ST8 0AR www.emschem.com EMS-Chemie is the polymer manufacturing division of the Swiss EMS-CHEMIE AG group based at Domat/Ems which employs approximately 700 people worldwide and whose group sales turnover in 2005 was CHF 1.253 billion, a 9.1% increase on the 2004 figure of CHF 1.149 billion. Operating income (EBIT) increased by 6.4% to CHF 216 million from CHF 203 million in 2004. The group’s performance polymers division specialises in the production of polyamides notably Grilon PA6, PA6.6 and Grilamid, low friction and wear, PA12 and also Grivory PPA polyphthalamides.

Epcos AG Corporate Centre PO Box 801709 81617 Munich Germany www.epcos.com Epcos, where Siemens AG and Matsushita Electronic Components (Europe) GmbH each retain shareholdings of 12.5% plus one share, continues to be one of the world’s largest manufacturers of passive electronic components with market leadership in Europe and number two position worldwide. It offers a portfolio of around 40,000 different products. Originally a 50:50 joint venture between Siemens and Matsushita prior to becoming a public company, the group now has design, manufacturing and marketing facilities in Europe, the Americas, Asia, Australia, New Zealand and South Africa. The group employed around 16,100 people worldwide in 2005, up 3% from the 15,600 the previous year, and posted sales of €1.24 billion, in the year from October 1st 2004 to September 30th 2005. The Epcos net sales situation on the basis of unaudited 2005 figures and denominated in euro millions, is shown in Table 6.1.

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Table 6.1 Epcos Group Net Sales (Euros) Product 2004 2005 (Unaudited) Capacitors 356 334 Ceramic Components 381 366 Surface Acoustic Wave Components 448 343 Ferrites and Inductors 202 168 Source: Annex to Epcos Press Release, November 17th 2005

% change -6% -4% -23% -17%

Epcos reported a more friendly business environment in the fourth quarter of the year with an improved level of orders. The prime contributor was the mobile phones sector. Taken against the previous third quarter of 2005 the slight reduction in new orders from Germany was balanced by better business elsewhere. There were double digit percentage increases in Asia, Europe apart from Germany, and the North American Free Trade Area. In China Epcos has signed a joint venture agreement, in which it has a 60% stake, with the Chinese Xiamen Xindico conglomerate to manufacture aluminium electrolytic capacitors for the rapidly growing Chinese market. In a change to its corporate philosophy, EPCOS is to focus even more on customer and application specific business. One of the consequences of this change has been the planned sale, for an estimated €86.5 million, of its tantalum capacitor business to the US capacitor manufacturer, Kemet. The sale includes the development, marketing and sales operations of the German plant at Heidenheim where tantalum capacitor manufacture will cease with consequent losses. Manufacture will continue at the Evora plant in Portugal. The tantalum business is believed to have been loss making for a number of years and the addition of tantalum polymer designs to the existing tantalum manganese dioxide range had not generated the planned success because of yield problems and high ramp-up costs to achieve series production. In the field of power capacitors the company claims that its portfolio is number one worldwide with its rugged range of aluminium models able to withstand the high ambient temperatures of car engine compartments. Epcos also makes film capacitors, where the plastic film may be up to ten times thinner than a human hair, and ultracapacitors. The capacitor division also supplies power factor correction modules as a cost saving service to customers.

General Electric Company 3135 Easton Turnpike PO Box 117 Fairfield Connecticut, CT 06828 USA www.ge.com General Electric’s advanced materials segment, which comprise GE Plastics, GE Silicones and GE Quartz, contributed sales revenue of $6.6 billion to the total 2005 General Electric sales revenue

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figure of $149.7 billion. Corresponding 2005 advanced materials segment profits contributed $867 million to the GE total figure of $18.3 billion. The GE Advanced Materials operation includes high-performance engineered plastics, structured products silicones and high-purity quartzware. The company’s range of engineering resins includes Cycolac ABS, Cycoloy PC/ABS blend, Geloy, Lexan PC, Noryl, high temperature Ultem polyetherimide, Valox PBT, Xenoy and Xylex polymer blends. Lexan LI1911R is an ultraclean PC grade which has been developed for use in the manufacture of semiconductors. The demand for Lexan compounds continues to increase for telecommunications applications and such products as CD-ROM, compact and digital video disks. Lexan EXL PC/siloxane resins, EXL9112 and EXL1434, are targeted at such applications as product housings for portable electronics, telecommunications and handheld computer applications. Flexible Noryl modified PPE resins, including halogen-free WCD910 and WCP860 have been released as an alternative to PVC, thermoplastic polyurethane and flame retardant PE in cord and plug applications in the electronics industry. Recent developments from GE Advanced Materials include ILLUMINEX display film and the X Gen product range where X stands for extreme. These products are said to ‘push the boundaries’ in terms of aesthetics, high/low temperature performance, weather and chemical resistance, mechanical and electrical tolerance. For example the XHT grade of Ultem polyetherimide has been described by GE as the highest heat, injection mouldable amorphous resin available today. Applications include flexible PCB able to withstand the new high soldering temperatures and moulded electrical interconnect devices. Other developments include metal-filled PC/ABS blends which provide special effects and eliminate painting. These Cycoloy engineered filler-brand PC/ABS resins can reduce or eliminate flow lines compared with conventional filler/resin systems. The new materials are flame retardant and halogenfree and have a high heat deflection temperature. The company is heavily engaged in R&D especially in nanotechnology. GE Advanced Materials was formed by the merger of the Plastics, Silicons and Quartz Divisions. In 2004 the LX2 plant was opened at Cartagena in Spain. Product developments include copolymer Lexan DVD and ecologically friendly compounds for electric and electronic components which are non-brominated and non-chlorinated flame retardant and which are intended to conform to WEEE, RoHS and certain voluntary ECO ecological standards. Other markets served include PCB as well as mobile phones and their associated battery cases.

Huntsman Corporation 500 Huntsman Way Salt Lake City UT 84108 USA www.huntsman.com The Huntsman Corporation is one of the world’s most diversified producers of differentiated and commodity polymers. It has around 11,300 employees with 7 operations in 22 countries. Reported

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2005 sales revenues were a record $12.96 billion, up 13% compared with the $11.43 billion reported in 2004. Gross profit in 2005 was $1.75 billion, up 27% on the 2004 figure of $1.38 billion. The operations of both the company and its customers were affected by the 2005 US Gulf of Mexico storms and this resulted in an estimated $140 million earnings shortfall. However, Huntsman does not anticipate any further significant impact on its 2006 figures. Huntsman, a major producer of PP and PE, is currently building what is claimed to be the world’s largest low-density polyethylene (LDPE) manufacturing facility at its Wilton chemical complex near Redcar in North-East England. This £200 million project, which uses technology licensed from ExxonMobil, is planned to be completed in the fourth quarter of 2007.

LG Chem LG Twin Towers 20, Yeouido-dong Yeongdeungpo-gu Seoul 150-721 Korea www.lgchem.com LG Chem is Korea’s largest chemical company both in size and performance with a global workforce of 10,000 employees. By 2008 it aims to become the world’s third largest chemical company in terms of earning rates and Asia’s third largest in terms of sales volume and stock value. In 2005 it reported sales of KRW (Korean Won) 7.43 trillion up by 4.2% from the 2004 figure of KRW 7.13 trillion. However, operating profit fell by 19.4% to KRW 422 billion in 2005 from KRW 523 billion in 2004. The exchange rate is around one thousand Korean Won to the US dollar. The main factors behind the fall in profits were reported to be the surging cost of raw materials and an unstable supply-demand balance in China for its petrochemical business. It had also experienced rechargeable battery quality problems. LG Chem is a vertically integrated company whose product range extends from polymers to portable fuel cells. The polymer portfolio includes ABS, ASA, PS, PBT, PC, POM, PP, PVC and SAN. The range of compounds on offer includes conductive versions obtained by adding conductive fillers to a variety of plastic materials. LG Chem supplies an extensive range of printed circuit board materials some of which are produced under licence from the Sanmina-SCI Corporation. The range includes standard and high Tg FR4, buried capacitance, high speed/low loss laminate and halogen-free materials. Other products include integrated circuit packaging materials and adhesiveless flexible polyimide copper clad laminates. The range also extends to OLED as well as other display and optical materials. The battery range is focused on lithium-ion and lithium-ion polymer designs. Recently a direct methanol fuel cell with a four thousand hour service life was announced. The methanol fuel is supplied in 200 cm3 cartridges which can each power a 25 W laptop computer for more than ten hours. In due course it is planned to widen the fuel cell capacity range so that it extends from 5 W to 50 W. LG Chem reported that the global market for portable fuel cells is expected to reach US $600 million rising to US $1.9 billion by 2010 with a high growth rate of 8.3% per year.

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Company Profiles

Plastic Logic Limited 34 Cambridge Science Park Milton Road Cambridge CB4 0FX www.plasticlogic.com This technological spin-off company, resulting from the commercialisation of Cambridge University research, was initially funded by venture capital and Dow Chemical. Now, with a team of 48 employees and funding of over $50 million of venture and equity capital, it is set to establish partnerships with manufacturers in order to move a laboratory process into mass production. The company is now hoping that by 2008 an electrophoretic display of text on rollable PET film will have reached commercialisation. The original objective was to exploit the technology to manufacture low cost plastic micro-chips using a process reported to utilise exotic plastic materials in a manufacturing technique similar to that of ink-jet printing. These materials come from such families as the polythiophenes and oligothiophenes which can be doped to change their fundamental insulating properties and thereafter become semiconductors. The company’s latest achievement, the world’s largest flexible organic active matrix display, was presented at the 12th International Displays Workshop at Takamatsu in Japan in December 2005. The 25 cm diagonal display, whose total thickness is less than 0.4 mm, comprises a flexible, Super Video Graphics Array (600 pixels by 800 pixels) with 100 ppi resolution and four levels of greyscale, printed active matrix backplane driving an electronic paper front plane from the US-based E Ink Corporation. The display is laminated to the E Ink Imaging Film which is an electrophoretic display material that looks like printed ink-on-paper and has been designed for use in paperlike electronic displays. The film only consumes battery power whilst the image is updated. The backplane substrate is made from low temperature PET supplied by DuPont Teijin Films which is easier to handle than possible alternatives such as of thin glass or steel foil. The current state of the company’s technology has been given in two recent presentations in America. In February 2006 CTO Cathy J Curling delivered a paper to the USDC Flexible Displays & Microelectronics Conference [1]. Later, in June 2006, Dr John Mills, VP Engineering, delivered a paper to the Society for Information Display (SID) Conference [2]. The company is participating in further R&D activity to the extent that planning permission was granted in mid-2005 for a £20 million technology centre to be built at Sedgefield in the North-East of England. This centre is being established by One North East, the area’s regional development agency, in partnership with Plastic Logic. The venture’s aim is to provide an open access facility for the entire European plastic electronics community. It will be built around a pilot line using technology developed by Plastic Logic. The facility’s equipment will include sophisticated ink jet and laser systems as well as test and measurement equipment. The project represents a scaling up of the current installation at Plastic Logic’s Cambridge plant. The technology employs a range of conductive media for the deposition process together with polythiophenes for semiconductors and other specialised products for electrical insulation.

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Rogers Corporation One Technology Drive PO Box 188 Rogers CT 06263-0188 USA www.rogerscorporation.com The Rogers Corporation is a specialist manufacturer of polymers and electronic materials with special emphasis on the communications and computing sectors. Products are manufactured in 14 plants including a European operation at Gent in Belgium. The US plants are based in Arizona, Connecticut and Illinois with Asian plants in China and Korea. There are also three joint ventures. In Japan, the Rogers Inoac Corporation (with partner Inoac) has plants at Nagoya and Mie and makes PORON elastomer materials and ENDUR elastomer components. The Polyimide Laminate Systems LLC partnership with Mitsui Chemicals Inc., is based in Chandler, Arizona and manufactures a customised flexible circuit material used in hard disk drive suspensions. In Taiwan at Taipei, the Rogers Chang Chun Technology Company Ltd., in partnership with the Chang Chun Plastics Company Ltd., manufactures and distributes Rogers R/flex Crystal adhesives and Rogers R/flex 9000 PET as well as PEN laminates and cover films. Rogers’ product range includes both high frequency and flexible PCB laminates. The company’s Durel division started off in 1988 as a joint venture with the 3M Corporation and was wholly integrated into Rogers in 2003. Its high volume production of DUREL3 electroluminescent backlighting systems, of which it is the world’s leading manufacturer, are widely used in portable electronics, communications and other applications. The latest IC designs are available in RoHS and WEEE compliant versions. Rogers recently reported 2005 net sales of $350 million which were 4% lower than the record figure of $365 million in 2004. On the basis of US generally accepted accounting principles the preliminary 2005 net income figure was $15.7 million.

SABIC Europe PO Box 5151 6130 PD Sittard The Netherlands www.sabic-europe.com SABIC Europe is a wholly-owned subsidiary of SABIC which is based in Saudi Arabia and which is the largest petrochemicals company in the Middle East, rated world number four in the worldwide polyolefins market. In 2002 SABIC bought DSM Petrochemicals which then comprised the business groups of DSM Polyethylenes, DSM Polypropylenes and DSM Hydrocarbons. SABIC had 2300 employees in 2002 with total sales turnover in excess of three billion euros. In addition to marketing company products made elsewhere in the world, SABIC Europe owns integrated world-scale production facilities at Geleen in the Netherlands and at Gelsenkirchen in Germany whose combined annual polyolefins production totals 2.5 million tonnes. In Europe SABIC’s sales of HDPE,

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Company Profiles

LDPE and linear low-density polyethylene exceed two million tonnes annually. SABIC’s total annual sales of PP and its compounds are around one million tonnes with the majority sourced from its European production facilities. Outside Europe SABIC produces melamine, polyesters, PS and PVC.

Samsung Electronics Samsung Main Building 250 2ga, Taepyung-ro Chung-gu Seoul South Korea www.samsung.com Samsung Electronics Co. Ltd., is reported to be Asia’s fifth largest company and the world’s major manufacturer of flat LCD and plasma screens and memory chips with 12 production plants in 12 countries. The company is reported to be seeking a site in Wroclaw, Poland to build refrigerators and possibly LCD monitors. Other reported planned investments include a joint venture with fellow South Korean company, LG Electronics, to invest almost $150 million to make LCD components at the Central Taiwan Science Park. Samsung has now begun shipping 80 cm and 100 cm LCD next generation TV panels from its newly opened second 7th generation production line. The company is the first volume producer of these advanced displays. The production line opened in January 2006 and the company expected to reach the line’s full monthly production capacity of 45,000 units by the end of June 2006.

Solutia Inc. PO Box 66760 St Louis MO 63166-6760 USA www.solutia.com Solutia, which was a spin off from the Monsanto company (St Louis, MO) in September 1997, has started the process which it hopes will result in its emergence from Chapter 11 Bankruptcy. The company’s management has reorganised the company on the basis of four business lines which include operations which are claimed to have industry-leading positions within their designated markets. Solutia is one of the world’s largest integrated producers of PA6.6. The integrated PA business accounts for around 58% of Solutia’s net sales. Solutia also claims to be the world’s largest producer of PVB laminated glazing interlayers, a business which accounts for a further 22% (approximately), of net sales. Plastic products, technical products, heat transfer fluids, aviation fluids and pharmaceutical services in total represent some 13% of net sales with the remaining 7%, or so, coming from CPFilms, Solutia’s branded aftermarket window films business.

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Polymers in Electronics

Solvay Chemicals Limited PO Box 7 Warrington Cheshire WA4 6HB www.solvay.com The Solvay Group, based in Brussels, broke new records in 2005, when compared with 2004 figures, with sales up by 18% to €8.562 billion and with net income up by a staggering 51% to €816 million. When analysed on a sector by sector basis pharmaceutical sales rose by 30%, chemicals by 14% and plastics by 13%. The sales of speciality polymers grew by 7% despite reported weakness in the automotive and semiconductor markets. Solvay has rapidly expanded its presence in the speciality polymers sector, where its products include polyamideimide (Torlon) and high performance sulfones (Supradel), by means of three recent strategic investments. In September 2005 it set up a new Technical Centre in Shanghai, Solvay High Performance Materials R&D (Shanghai) Co. Ltd., which began operations in the first quarter of 2006. The main aim of the centre is to provide clients in China with R&D services and, by offering innovative solutions, to assist them with design and processing of new components using Solvay’s range of speciality polymers. The centre will also provide a base for its local chemical and plastics sector staff in state-of-the-art facilities. Solvay Speciality Polymer sales in the Asian region already exceed €100 million and are continuing to grow rapidly. The Solvay Group has been active in China since 1995 and has operated via joint ventures and commercial representation. In December 2005 Solvay announced the acquisition of the Polymers Division of Gharda Chemicals in India. The Division operates a state-of-the-art R&D centre and production plant at Panoli in Gujarat State which employs 180 employees with sales revenues in excess of US $10 million. The acquisition, which provides Solvay’s Speciality Polymers Strategic Business Unit with a foothold in India, is to be combined with the US Solvay Advanced Polymers LLC unit at Alpharetta in Georgia. One of the attractions of the Indian investment is that it manufactures PEEK using its own in-house technology and Solvay plans an early increase in production of this polymer as part of the group’s broader plan to establish a strong market position in PEEK. However some users find the Indian product more difficult to use than PEEK from Victrex and are prepared to pay its higher price. Solvay further boosted its polymer portfolio in January 2006 with the acquisition of Mississippi Polymer Technologies a start-up company whose main attraction is the PARMAX family of melt-processable, transparent, amorphous, rigid-rod thermoplastics which are claimed to exhibit a unique combination of strength, stiffness and hardness. The chemical resistance of PARMAX is claimed to be comparable with semi-crystalline materials and to be unsurpassed by any other transparent polymer.

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Company Profiles

Teijin 1-1, Uchisaiwaicho 2-chome Chiyoda-ku Tokyo 100-8585 Japan www.teijin.co.jp Teijin’s developments include BESFIGHT carbon fibre whose thermal conductivity exceeds that of metals. The company claims that resin compounds containing these carbon fibres can be processed cheaply to form various types of casings and components which are both light and strong. Teijin plans to optimise these qualities in products to be offered for such applications as mobile phone components. Teijin’s main carbon fibre production plants are located in Mishima (Japan) where 3,700 tons annually are produced from acrylonitrile raw material. The Wuppertal plant in Germany uses a precursor to produce 1,900 tons annually. A precursor is also used at the US Knoxville plant to produce 3,500 tons annually. The fibre produced is used in a wide range of applications for the aircraft and automotive industries in particular. Electronics uses include audio speakers, compact disk parts and integrated circuit carriers. Teijin is a major producer of Panlite PC resin with manufacturing and sales locations in Japan, China and Singapore. Interestingly in 2005, Teijin signed a letter of intent with Germany’s Bayer Material Science AG for the two companies to supply each other with PC resin. In the manufacture and sale of PET film its DuPont Teijin 50% owned joint ventures operate in Japan, the US, Indonesia, Luxembourg and Scotland. Teijin’s polyester PET films whose applications include flexible printing substrates, membrane switches, PCB and touch panels are sold under the brands Teijin, Tetoron film, Melinex film, Mylar film and Teflex film. Teijin’s proprietary PEN film, sold as Teonex, has greater strength, rigidity and heat resistance than PET film. Its coated films, which include OPTFINE and Purex, are manufactured using proprietary nanostructure control and coating technologies. PUREACE is a solvent-cast PC film used in mobile phones, personal digital assistants (PDA) and other handheld electronic equipment. Teijin is endeavouring to restore profitability to its European films operations by investigating productivity improvements and by looking at possible reductions in workforce numbers. In 2003, the Teijin Advanced Films Limited joint venture with the Asahi Kasei Corporation was launched using polyparaphenylene terephthalamide to manufacture Aramica. Another Teijin joint venture, with the US Great Lakes Chemical Corporation, has involved the combination of the two companies’ worldwide brominated carbonate oligomer activities as part of their polymer flame retardant marketing operation. Teijin Solufill Limited produces Solufill a high porosity PE engineering film formerly made by a joint venture with DSM whose interests were bought out by Teijin. Solufill is filled with a special ceramic powder. Solufill was formerly used in the manufacture of bulk multilayer ceramic capacitors but in 2005 Teijin decided to withdraw from this application due to weakening electronic component prices and a worsening market environment. However, Solupor, a sister product is being supplied for use as a battery separator.

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Teijin is consolidating its position in the People’s Republic of China where its DuPont Teijin Films China Limited and two joint ventures with local partners are opening large-scale new production facilities in order to meet local demand in this rapidly growing market. Investment in Japan resulted in the start-up of a second PC production line dedicated to the manufacture of sheet to be used in diffusion plates or large screen LCD-TV direct-type backlights. PC sheets have higher heat resistance than the PMMA and methacrylic material formerly used.

Ticona GmbH Professor Staudinger Strasse 65451 Kelsterbach Germany www.ticona.com Ticona was formed in 1961 as a joint venture of Hoechst AG and the Celanese Corporation of America. Hoechst acquired Celanese in 1987 and, following subsequent restructuring, established Celanese AG in 1999 as a separate company within which Ticona operates independently. It is now the technical polymers business of Celanese AG with a worldwide workforce of around 1,800 and production, compounding and research facilities in Germany (Kelsterbach and Oberhausen), USA and Brazil. Company affiliates include Fortron Industries in the US, Polyplastics Co. Ltd., with operations in Japan, Malaysia and Taiwan plus PTM Engineering Plastics at Nantong in China. Group sales in 2004 totalled $863 million. Ticona is a minority shareholder in Polyplastics Co. Ltd., Japan with a 45% holding, the majority shareholder is Daicel Chemical Industries Ltd., with a 55% holding. Other joint manufacturing ventures include one with DSM to produce PBT. In December 2005 Celanese contracted to sell its loss-making Topas, cyclo-olefin copolymers (COC) operation to a Daicel (55%)/Polyplastics (45%) joint venture. This COC business has approximately 100 employees at production and research facilities in Oberhausen and Frankfurt as well as in the UK. Following the sale, which involves the transfer of all production facilities and employees to the new joint venture, the headquarters of the business will remain in Germany. Ironically, Mitsui Chemicals announced plans to increase COC production by 600 tonnes per year, citing forecast rising demand of 20% per year for its own Apel COC product. Earlier, Ticona had announced its intention to withdraw from its Pemeas joint venture which had lost US$12 million in 2003. Ticona products include polyoxymethylene (POM) which are distributed worldwide under the Celcon and Hostaform brands. Ticona’s polyester product line includes Celanex Duranex (PBT), Impet (PET), Riteflex (TPE-E) and Vandar thermoplastic polyester blends. Ticona also claims major world status in ultra-high molecular weight polyethylene GUR, Vectra (LCP). Other products include Celstran and Compel which are long fibre reinforced thermoplastics and which are some of the company’s advanced materials along with its Fortron PPS. Celanex XFR is a new range of PBT grades which are free from brominated flame retardants and which therefore comply with the latest recycling regulations. The four grades are: unreinforced, and three reinforced with 10%, 20% or 30% glass fibre. In partnership with SGL Carbon, Ticona have developed a highly graphite filled Vectra grade for the injection moulding of bipolar fuel cell plates. These plates can be moulded on a 10 second cycle time and

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Company Profiles

are seen as a lower weight substitute for plates made from milled graphite or stainless steel coated with gold. Furthermore they resist the aggressive media which interact in fuel cells and also have the benefit of being corrosion-proof. Additionally they will retain their shape even at temperatures as high as 240 ºC.

Toray Europe Limited (TEL) Third Floor 7 Old Park Lane London W1K 1AD www.toray.com In the year to March 31st 2005, on the basis of an exchange rate of 107 yen to the US dollar, Toray’s total net sales were $12.137 billion with an operating income of $757 million and a net income of $321 million. This Japanese company holds world market leadership in polyester films and carbon fibre composite materials. The company’s advanced materials business is based on its core technologies of organic synthetic chemistry, polymer chemistry and biochemistry. Advanced materials projects include organic electroluminescent materials, next generation flexible PCB, flat panel display materials and nanotechnology applications. Products include ABS, LCP, PA, POM, PBT and PPS films, resins, moulded products and components. Toray also produces carbon fibres and composites. Toray is in the fortunate position of supplying its Lumirror PET film to both LCD and plasma display panel (PDP) flat panel manufacturers. Toray is also a major supplier of polyester film to capacitor manufacturers and in January 2005 expanded production at its Yahua Toray Polyester Film plant. In China, Toray’s Yihna Toray Polyester Film joint venture with the Chinese Yihna Group is installing its third, 500 tonnes per year production line, specifically for ultrathin capacitors, because the market for capacitor grade PET film is expanding rapidly in China. Its two existing PET production lines serve the packaging and industrial materials markets. Other sales growth areas include Metaloyal, an electrolytically plated two-layer flexible substrate film used in electronic circuits, where production capacity is being increased by 50% at its Japanese Fukushima plant in Kagamiishi where the annual production capacity was scheduled to reach the rate of one million square metres in January 2006.

Total SA 2 Place de la Coupole La Defense 6 92400 Courbevoie France www.total.com Total is the world’s fourth largest integrated listed oil and gas company and continues to benefit from rising oil prices to the extent that 2005 group sales rose by 17.4% to €143.168 billion, compared

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with €121.998 billion in 2004. Operating income rose by 37% to €23.669 billion in 2005 from €17.217 billion in 2004. Organisational changes in the structure of the chemicals business were implemented in October 2004 with the creation of Arkema which is a new independent legal entity, which was spun off from Total on May 18th 2006, and is responsible for vinyl products, industrial chemicals and performance products. The other two units which form the chemicals business are Total Petrochemicals, which covers all petrochemical operations and fertilisers, and Specialities which groups together the rubber processing activities of Hutchinson, the Bostik adhesives business, the Atotech electroplating business and the resins activities of Cray Valley and Sartomer. The key figures for chemicals are shown in Table 6.2.

Table 6.2 Sales of Total Petrochemicals Chemicals key figures (billion euros) 2005

2004

Change

22.3

20.0

+11%

Base chemicals

10.2

8.9

+16%

Specialities

6.5

6.0

+8%

Arkema

5.6

5.2

+8%

Corporate Chemicals

–

0.07

not significant

Adjusted Operating income

1.35

1.14

+19%

Base chemicals

0.58

0.51

+15%

Specialities

0.55

0.50

+10%

Arkema

0.23

0.12

+96%

(0.01)

0.01

not significant

Net Adjusted Operating income

0.96

0.77

+25%

Investments

1.12

0.95

+17%

Sales Sales by business unit

Corporate Chemicals (loss)

Source: Company press release February 16th 2006

Total claims to be the world’s fifth largest producer of petrochemicals with a world ranking of number 3 in both PP and PS. In technical polymers Arkema claims world market leadership in the production of PA11 and 12 (Rilsan) as well as in PVDF and fluoropolymers (Kynar). Arkema also claims world leadership in the production of PMMA with the Altuglas and Plexiglas brands. Arkema manufactures Nanostrength nanoparticles. Arkema has expanded its PVDF manufacturing capacity at Pierre-Benite near Orleans in France. One of Arkema’s main polymer R&D projects is the development of fuel cells using PVDF conductive material for the membranes. Total is committed to the development of renewable energy systems including wind, solar and photovoltaic power. Tenesol, its 50:50 joint venture with Electricité de France (EDF), claims to be a

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Company Profiles

world leader in photovoltaics. With headquarters in Lyon and production facilities in Toulouse and South Africa, Tenesol designs, manufactures and installs solar power systems. In partnership with its EDF and Total parents, Tenesol is implementing decentralised rural electrification programmes in Morocco, Mali and South Africa with the ultimate objective of supplying more than 70,000 isolated households with photovoltaic electricity. Total is a 42.5% shareholder in Photovoltech, the Belgian photovoltaic cell manufacturer, whose other shareholders are Electrabel (42.5%) and Imec (15%). Imec (Interuniversity Microelectronics Centre) is Europe’s leading research establishment in the field of microelectronics. Photovoltech, which holds an exclusive licence from Imec to use its technologies, has been building up production at its Tienen plant where the planned annual output capacity is 80 MWp. MWp is defined as megawatt-peak where watt-peak is a solar panel unit which will generate one watt of electricity in good sunlight.

TT Electronics plc Clive House 12-18 Queens Road Weybridge Surrey KT13 9XB www.ttelectronics.com TT Electronics is an unusual example of a company that has rationalised its manufacturing activities whilst retaining its core electronic and electrical engineering interests. The company’s strategy is to dispose of non-core electrical operations at attractive prices and re-invest the proceeds in growth businesses. To this end the company’s AEI Power Cables Division at Gravesend in Kent has been closed and the site sold. In Scotland there has been a major manufacturing reduction at Prestwick Circuits which in future will supply its customers with Asia-sourced PCB. On the positive side TT Electronics has acquired the entire share capital of Dage Limited and its subsidiaries. Dage, now renamed TTeis Ltd., manufactures technologically advanced backplane assemblies, systems integration solutions and PCB assemblies at its UK factory at Aylesbury and its Suzhou plant near Shanghai in China. TT electronics continues to carry out contract electronic manufacturing at its AB Electronic Assemblies plant at Rogerstone in South Wales and Welwyn Systems plant at Blyth in Northumberland. TT Electronics continues to be a major manufacturer of a wide range of passive electronic components, hybrid microcircuits and electrical connectors. The company has also successfully developed a wide range of temperature and pressure sensors and recently announced plans to extend its Dresden plan in Germany by 2325 m2. In 2004 TT Electronics reported full year revenue of £597.4 million accompanied by an operating profit, before exceptional items, of £33 million. In his initial trading update for 2005 the Executive Chairman, John Newman, reported that 2005 had been a year of consolidation for the company.

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Tyco Electronics UK Limited Faraday Road Dorcan Swindon Wiltshire SN3 5HH www.tycoelectronics.co.uk By dint of acquisition and amalgamation Tyco Electronics has become the world’s largest passive components supplier with its electronics business reporting a 2005 sales revenue of $12.2 billion which accounts for 30.7% of the corporation’s total revenue of $39.7 billion. Tyco employs over 250,000 people worldwide and its extensive product range includes antennas, capacitors, connectors, heat sinks, PCB, relays, resistors, sensors, switches, terminal blocks and touch screens. Company trademarks include AMP, Augat, Elcon, Neohm, Potter & Broomfield, Raychem and Schrack.

Victrex plc Victrex Technology Centre Hillhouse International Thornton Cleveleys Lancashire FY5 4QD www.victrex.com Victrex is best known for its semi-crystalline polymer PEEK, which is insoluble in all common solvents and can be used at temperatures of up to 300 ºC. PEEK’s 2005 total sales volume was 1,972 tonnes a 9.4% increase from the 2004 figure of 1,802 tonnes. Victrex USA has reformulated its PEEK products in order for them to be used for lead-free soldering of components. As a consequence PEEK is challenging use of PPS in such applications. The company reported a 14.8% sales increase to £101.6 million in the year to September 30th 2005 with gross profits up by 21.7% to £58.0 million. Victrex has wholly owned sales subsidiaries in Germany and the US with a 51% owned sales subsidiary in Japan where the joint venture partner is Mitsui Chemicals. Other developments include the opening of the company’s first Asian sales office in Hong Kong. Victrex is also investing in a new Asian Innovation and Technology Centre which will provide customers with expertise in material specification, testing, research and application development. Victrex has now purchased the operations of Degussa AG relating to the manufacture of 4, 4–difluorobenzophenone (BDF) which is produced by the oxidation of 4, 4–difluorodiphenyl methane (DFDPM) whose manufacturing facilities had already been bought by Victrex. The purchase from Degussa also includes a plant to manufacture fluoroboric acid. The expansion of the business is being underscored by the £29 million investment in the construction of a second VICTREX PEEK polymer powder manufacturing plant on the company’s main UK Lancashire site at Thornton Cleveleys.

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Company Profiles

The company addresses the market sectors of electronics, industrial and transport and also owns Invibio Ltd., which it claims is an innovative global leader in the field of high performance biomaterial solutions for medical device manufacturers. Products offered include PEEK-OPTIMA, PEEK-CLASSIX and ENDOLIGN which is a continuous carbon fibre reinforced product. In the electronics segment there are components built to tight tolerances with moulding flexibility needed for intricate snap-fit designs. This permits the mass production of highly complex finished components which have no need to be machined further. Other applications include handling equipment for semiconductor and LCD flat panel fabrication.

References 1.

C. Curling, Proceedings of USDC Flexible Displays and Microelectronics Conference, 2006, Phoenix, AZ, USA.

2.

S.E. Burns et al., in Proceedings of the Society for Information Display (SID), San Francisco, CA, USA, 2006, Paper 7.4.

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108

7

Future Outlook

7.1 Optical Applications The growing use of fibre optic cables has stimulated the demand for ancillary components to facilitate connections and other requirements. One interesting development at Toronto University in Canada has been the production of a new hybrid plastic which can produce light at the wavelengths used in fibre optic communications thus paving the way for an optical computer chip. Use of optical fibre is found in the car, the home, small offices and into consumer products. Polymer optical fibres (POF) are cheaper than glass and are easier to manufacture and use, although their maximum effective operating length is of the order of a few hundred metres. POF offer the prospect of being able to employ simple low cost moulded plugs to make rapid connections. One contributory factor to the simplicity is the fact that plastic optical fibre has a diameter of up to 1 mm which is around eight times the diameter of a standard single mode silica fibre. POF is more tolerant of connection misalignment than silica. COC, previously three times the price of such competing optical resins as acrylic and PC, were pioneered in Japan for such optical applications as film and sheet for LCD. They have also made inroads into the market as light-guide panels for laptop computers where resulting weight savings have justified the price premium.

7.2 Search for New Products One of the problems in the UK is the frequent inability to translate a good idea into a saleable product. This study has provided examples of spin-offs from university laboratories which have developed new products and then licensed the technology to multinational companies which then proceed to profitable exploitation. Even when an inventor makes a major discovery, as with Mr Dyson and his vacuum cleaner, it is often impossible to find a domestic manufacturer willing to exploit the product commercially though in Mr Dyson’s case he established his own manufacturing company. The problem is also present in the state sector where the government has sought to commercialise new technology discovered in military research establishments. Examples of these efforts have had mixed results but successes include technologies relating to lithium batteries and flat panel displays. January 2006 has marked the launch of a new initiative by the DTI which is providing £11,000,000 over three years to the Materials Knowledge Transfer Network (KTN) whose projects include the development of self-healing composite material by QinetiQ. Defence applications are important markets for electronic components made from plastics because they are far more difficult to detect than metal components. Already innovative new ground penetrating radar detectors are being used to seek out minimum-metal plastic landmines.

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Bayer MaterialScience has developed an innovative, forgery-proof data storage system which utilises photo addressable polymers which are constructed from its new breed of long-chain molecules which align themselves in parallel under certain kinds of laser light thereby creating patterns in the plastic, the holograms. The system takes the form of a special plastic film which can store data using a particular system of laser light which encodes the information in the form of a hologram. In order to access the information a second laser of the same type is needed. The electronics industry is constantly seeking new products which will attain ‘must have’ status. Whilst mobile phone manufacturers have successfully persuaded their customers to upgrade by introducing additional services and features, the increasing complexity of the handsets has become just too complicated for some potential customers. Invariably, some new products in their infancy are too expensive to sell in large numbers but widespread acceptance can bring economies of scale and lower prices which drive up demand still further. Examples of this trend include car satellite navigation systems, digital cameras and large screen television sets which incorporate plasma or other technologies. In some cases competition is so fierce that new products may even be launched at below cost prices as in the case of video games consoles, the Xbox 360 for example, where revenue from the future sale of video games and anticipated cuts in future production costs are seen as justifying the initial stance. In a recent statement the Head of Multimedia at Nokia, Anssi Vanjoki, foresaw the convergence of the telecommunications industry with IT and the media, a trend supported by Nokia’s emergence in 2005 as the largest manufacturer of cameras and MP3 music players with sales of 100 million camera phones and 40 million music handsets. The need for a continuous flow of new products is underlined by the evidence of certain products passing their peak in key markets. The latest example being digital cameras where a downturn has been identified in the North American market although growth continues in Eastern Europe, China, India and Korea as well as certain other markets. This situation mirrors the state of affairs in the mobile phone market. Already Kyocera/Yashica has cut back, as has Konica Minolta. Another polymer using sector where, in this case, the polymer supplier is probably in a win-win situation is in the high-capacity video disk market. Here the battle lines have been drawn between two competing systems, HD-DVD and Blu-ray. Arguably the current situation has arisen as a consequence of the arrival of high definition television sets and the inability of existing DVD to store the necessary data to display a film in a HDTV format on a single disk which has a 4.7 GB (gigabyte) capability. The HD-DVD disk can store 15 GB on a single layer disk or 30 GB on a dual-layer disk. The corresponding figures for Blu-ray disks are 25 GB and 50 GB, respectively. HD-DVD supported are said to include Intel, Microsoft, Hewlett-Packard and Toshiba whereas the Blu-ray team is said to include all but one of Hollywood’s studios, Apple, Dell Philips and Sony. The shorter wavelength blue-violet (405 nm) laser is used by Blu-ray to secure spot sizes of 160, 149 or 138 nm to achieve possible disk capacities of 23.3, 25 or 27 GB with double layer blue laser disks raising the potential capacity to 50 GB of data. In an interesting development designed to eliminate return visits to rental shops Flexplay Technologies and Walt Disney launched the ‘ez-D’ a disposable DVD which erases itself two days after being removed from its packaging. The erasure is the result of a special coating which reacts with air and turns black thus becoming unreadable by DVD players. In the American trial markets, Flexplay established a recycling programme before launching the disks whereby customers could go to the company’s website and print out mailing labels and postage and request a mailing envelope. Flexplay would then send the returned disks to GreenDisk who would aggregate them with other disks before sending them to plastics recyclers.

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In another development in this sector, Bayer MaterialScience has invested five million dollars in the leading American optical storage company, InPhase Technologies, with whom it has signed a joint development agreement. This partnership has been targeted towards the launch of a holographic storage medium using products from Bayer. InPhase’s holographic disks have 50 times the memory capacity of a DVD or 460 times that of a CD. Bayer MaterialScience is also the source of holographic storage material required for the powerful and secure systems sought by mobile data carriers. The technique involves coating Makrofol ID PC film with a laser-writable special polymer to create a storage medium to save data using holography. To this end GE Advanced Materials and Plextor have established a joint development agreement to develop and market a 52X CD-R/RW optical disk drive able to recognise GE’s SecureQQ resins on disks. These highly specialised drives and disk media define a system for the secure delivery of digital content, typically music and films, to paying consumers. Working on the basis that necessity is the mother of invention a new anti-intrusion shell product from RocTool would appear to satisfy a number of needs. The shell, using reformulated conductive polyester composite material, incorporates a smart card within the moulding which, in the event of threatened integrity, can transmit information. Typical product applications include the transport of hazardous or sensitive materials, protection of electronic equipment, security of buildings, the ensuring of system integrity in IT systems and for double protection in an alarm system. For those with sight problems the University of Tokyo has developed a thin flexible polymer display where a system of Nafion polymer cantilevers pushes up 0.9 mm radius dots through a 10 μm polydimethylsilane membrane to a height of 0.25 mm above the display surface to form a Braille display. The thin flexible 1 mm thick bendable display is driven by a Braille input. The system is powered at 3 V which is sufficient to cause electro-osmosis which bends the cantilever by differential osmotic pressure. Removal of the voltage allows the cantilever to straighten up and though, theoretically the device can operate at up to 2 Hz, this is not physically possible with the installed organic transistor circuitry. The dots are displayed in a typical 2 x 3 dot Braille character array - the 4 cm prototype features four rows of six characters. The impetus behind the development of light emitting technology which holds the promise of low power consumption devices with relatively low manufacturing costs is destined to result in the launch of a host of new products. Displays of all kinds can be produced in a laminar, flexible form and incorporated in a wide range of materials which include clothing. The technology can be incorporated in a variety of different shapes, typically those that are found in packaging applications. Another concept is the creation of paper-thin material which could carry messages or be used as type of light emitting wallpaper.

7.3 Superconducting Plastics This category can be said to include quantum tunnelling composites which are currently under development. These unusual materials are insulators under normal operating conditions but become metal-like conductors when pressure is applied. Such materials can be used for sensors and switch substrates for example. They can be cast, extruded, moulded, machined or screen printed by standard processes.

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7.4 Asia - Opportunity or Threat The total annual demand for thermoplastics in South-East Asia has been estimated to be in the order of 50,000,000 tonnes. However, from the Western viewpoint, we do not always appreciate the jockeying for supremacy taking place between individual Asian countries, especially between Japan and South Korea. In electronics terms Korean groups, especially Samsung SDI have dominated LCD markets and have been on track to dominate the plasma display market, a strategy the Japanese groups aim to overcome. In 2004, South Korea had a 46% share of worldwide Thin Film Transistor Liquid Crystal Displays (TFT-LCD) whereas Taiwan had a 44% share. However, Taiwan’s market share is expected to overtake that of South Korea in 2006. One interesting aspect of Taiwan’s apparent growth strategy occurred in Finland where the Foxconn Taiwanese subcontractor to Nokia is understood to have purchased another Nokia supplier in Finland, Eimo, subsequently closing its manufacturing operations there and just leaving the service function in that country. In future Chinese companies will certainly raise their profile as in the case of the Chinese Lenovo company’s acquisition of IBM’s personal computer business. Other Asian countries with higher cost levels than the major manufacturing countries in the region still manage to compete and Malaysia, for example, is expanding its production of plastic parts for electronic components. It is difficult to come to terms with the consequences of GDP growth of 8% per year in China where the economy is forecast to maintain this growth rate over the next few years. China’s population is currently around 1.3 billion and its annual consumption of plastics products is approximately 1 kg per head compared with a 40 kg figure for Western Europe. It would appear that this consumption figure is bound to increase as the population becomes more prosperous the big question being to what extent can Europe benefit from the situation? Japanese companies have suffered as manufacturing operations have moved to countries with lower costs. Sanyo, which is still the world’s largest manufacturer of rechargeable batteries, is under financial stress, and is being advised to withdraw from segments where it is unable to compete, notably white goods and audio-visual products. Furthermore, in the mobile phone handset market, Sanyo recently announced a joint venture with Nokia in which Sanyo will have a controlling interest. The venture, with its estimated 20% market share, combines Sanyo’s skills in the mid and high-end sector of the market whereas Nokia will focus on the lower cost Code Division Multiple Access (CDMA) sector. CDMA technology, where Samsung is the leading manufacturer, is the main rival to Global Standard or System for Mobile (GSM), the most popular wireless technology. To the extent that it provides quality products at very attractive prices China is a prime source of components with UK brokers, for example, acting as intermediaries between Chinese injection moulding companies and their potential customers. The connector manufacturing industry illustrates the trend of closure of factories in Western Europe by multinational companies who have opted to establish production facilities in that country. Such transfers reduce the demand for polymers in Western Europe. However some European companies are fighting back and DSM, for example, decided in 2005, to establish a new state-of-the-art plant at Jiangyn in China to expand its engineering plastics compounding capacity with a 2006 completion date. As well as doubling the capacity of the company’s Stanyl PA46, Akulon PA6 and Arnite polyester compounding facilities the new site will also accept the relocation of DSM’s existing facilities at Zhouzhuang. The new site is sufficiently large to accommodate further expansion of DSM Engineering Plastics activities or the establishment of new facilities by other DSM businesses.

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Outside observers have seen dramatic increases in the quality of Chinese products in recent years and one was quoted as expressing surprise that, not only were the Chinese aware of future European legislation, they were actually complying with it. In Europe some companies have responded to low cost Asian competition by customising their products and now offer complete packages rather than individual connectors, for example, since these have tended to become commodity items. These packages may well include associated cabling, filters, power supplies, card frames and racking. A different approach has been taken by EPCOS, the German multinational passive electronics components manufacturer. Although, between 2004 and 2005, it increased its worldwide workforce by 3% from 15,600 to 16,100, the increase almost exclusively took place in countries with low labour costs, especially China and the Czech Republic. The quoted approximate geographic distribution of the workforce is Asia (48%), Germany (13%), Rest of Europe (28%) and the Americas (11%). Multinational companies are well able to control the quality of the components they source in China but there are possible pitfalls for the independent distributor seeking to source products from individual companies in that country with a real risk of ending up with fraudulent or substandard material. To overcome this potential problem the Electronic Reseller Association International has linked up with the White Horse Strategic Solutions, a testing company based in Hong Kong, to provide convenient and independent testing facilities. In future there is a possibility that China might become a victim of its own success as labour costs are reported to be rising due to a shortage of skilled workers and raw material costs are rising as a result of the increased worldwide demand for oil and commodities, especially as copper. Low prices in the past failed to provide suppliers with the incentive to increase production capcity. In some areas the utilities are under pressure. Even without a revaluation of China’s currency, manufacturing costs could rise by 10% this year. However, to put things in perspective it is worth noting that average wage rates in China are around 5% of comparable UK figures. Whilst China is undoubtedly on track to be a leading economic superpower and will shortly leapfrog the UK into world number four spot in GDP terms, its science superpower status trails behind somewhat. In an interesting recent remark the anonymous Research and Development Director of a leading manufacturer observed that whilst Chinese telecommunications are strong in the field of development, their success in basic research is nowhere near as good. Despite its economic problems in recent years it is important not to forget Japan whose companies may also be on the acquisition trail in the West. For example Fuji Photo Film recently agreed to acquire a majority stake in the American Arch Chemicals’ microelectronics business for $160 million. The turnover of $135 million is derived from the sale of photoresists, formulated product polyimides and thin-film systems used to manufacture semiconductors and flat panel displays. Fuji has also acquired Arch’s 49% holding in the two companies’ joint venture FujiFilmArch. Fuji subsequently stated that it would broaden the scope of the Arch microelectronics business to cover the whole of the electronics sector including the high-density mounting field.

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8

Abbreviations and Acronyms

3D-MID

Three-dimensional electronic circuits

ABS

Acrylonitrile-butadiene-styrene

AC

Alternating current

AIM

Alternative investment market

AMAT

Advanced molecular agitation technology

AMLCD

Active matrix liquid crystal display(s)

ASA

Acrylate styrene acrylonitrile

ATEX

From the French ‘ATmospheres EXplosible’

ATM

Automated teller machines

BCE

Block copolymer electrolyte(s)

BMBF

German Federal Ministry of Education and Research

BPF

British Plastics Federation

BSI

British Standards Institute

CAD

Computer aided design

CAS

Chinese Academy of Sciences

CD

Compact disk(s)

CDMA

Code division multiple access

CD-ROM

Compact disk – read only memory

CDT

Cambridge Display Technology

CEA

Consumer Electronics Association (US)

CEM

Contract electronics manufacturer(s)

CJC

Clean Japan Centre

CMO

Chi Mei Optoelectronics

CNT

Carbon nanotube(s)

COC

Cyclo-olefin copolymers

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CR

Polychloroprene elastomer

CRT

Cathode ray tube(s)

CSTN

Colour super-twisted nematic

DC

Direct current

DDE

DuPont Dow Elastomers LLC

DFDPM

4, 4–Difluorodiphenyl methane

DOE

Department of Energy

DTAM

Distributor total available component market

DTI

Department of Trade and Industry

DVD

Digital video disk(s)

EBIT

Earnings before interest and taxes

EDF

Electricité de France

EDIA

European Display Industry Association

EECA

European Component Manufacturers Association

EMC

Electromagnetic compatibility

EMI

Electromagnetic interference

EPCIA

European Passive Components Industry Association

EPDM

Ethylene-propylene diene elastomer

EPIA

European Packaging and Interconnection Association

EPS

Expanded polystyrene

ESIA

European Semiconductor Industry Association

ESR

Equivalent series resistance

EU

European Union

FEP

A polymer of tetrafluoroethylene and hexafluoropropylene

FET

Field effect transistor(s)

FFC

Flat flex cable

FIM

Film insert moulding

FPC

Flexible printed circuit

FPD

Flat panel display(s)

FPM

Fluoroelastomer

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Abbreviations and Acronyms

FR-4

Flame retardant

FSTN

Film super-twisted nematic

GDP

Gross domestic product

GPRS

General packet radio service

GSM

Global standard or system for mobile

HD

High definition

HDPE

High-density polyethylene

HDTV

High definition television(s)

HIPS

High-impact polystyrene

HVM

High value manufacturing

IC

Integrated circuit

ICCAS

CAS Institute of Chemistry

ICP

Intrinsically conducting polymer(s)

IP

Ingress protection

IT

Information technology

ITO

Indium tin oxide

KRW

Korean Won

KTN

Knowledge transfer network

LCD

Liquid crystal display(s)

LCP

Liquid crystalline polymers (s)

LDPE

Low-density polyethylene

LDS

Laser direct structuring

LED

Light-emitting diode(s)

LEP

Light-emitting polymers(s)

LIP

Lithium-ion-polymer cells

LMP

Lithium-metal-polymer

MEC

Manufacturing Engineering Centre

MID

Moulded interconnect device(s)

MIT

Massachusetts Institute of Technology

MOD

Ministry of Defence

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MOF

Metal organic framework(s)

MPPE

Modified-polyphenylene ether

MRSA

Methacillin resistant Staphylococcus aureus

MWT

Molecular Waste Technologies Inc.

NASA

National Aeronautics and Space Administration

NASDAQ

National Association of Securities Dealers Automated Quotation (system)

NBR

Nitrile butadiene rubber

NCA

A blend of nickel - cobalt - aluminium dioxide

NCM

Nickel-cobalt-manganese

NiPdAu

Nickel-palladium-gold

OEM

Original equipment manufacturer(s)

OLED

Organic light-emitting diode(s)

ORB

Organic-radical rechargeable battery

PA

Polyamide

PAFC

Phosphoric acid fuel cell(s)

PBB

Polybrominated biphenyl(s)

PBDE

Polybrominated diphenyl ether(s)

PBT

Polybutylene terephthalate(s)

PC

Polycarbonate(s)

PCB

Printed circuit board(s)

PCT

Polycyclohexylene dimethyl terephthalate

PDA

Personal digital assistant

PDP

Plasma display panel(s)

PE

Polyethylene

PEDOT

Polyethylene dioxythiophene

PEDT

Poly(3,4-ethylenedioxyhiophene)

PEEK

Polyether ether ketone

PEEK-HT

High temperature PEEK

PEI

Polyetherimide

PEM

Polymer electrolyte membrane

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Abbreviations and Acronyms

PEN

Polyethylene naphthalate

PES

Polyethersulfone

PET

Polyethylene terephthalate

PFA

A polymer of tetrafluoroethylene and perfluorovinylether

PI

Polyimide(s)

PLA

Polylactic acid

PLED

Polymer light emitting diode(s)

PMMA

Polymethylmethacrylate

POEM

Polyoxyethylene methacrylate

POF

Plastic optical fibre(s)

P-OLED

Polymer organic light emitting diode

POM

Acetal copolymer(s)

PP

Polypropylene

PPA

Polyphthalamides(s)

PPE

Polyphenylene

PPO

Polyphenylene oxide

PPS

Polyethylene sulfide

PS

Polystyrene

PSSA

Crosslinked polystyrene sulfonic acid

PSU

Polysulfone

PTC

Positive temperature coefficient

PTF

Polymer thick film

PTFE

Polytetrafluoroethylene

PTMA

Polytetramethylpiperidinyloxy methacrylate

PU

Polyurethane(s)

PVB

Polyvinyl butyral

PVC

Polyvinyl chloride

R&D

Research & Development

RF

Radio frequency

RFI

Radio frequency interference

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RFID

Radio-frequency identification tags

RMS

Root mean square current ratings

RoHS

Restriction of Hazardous Substances

RTI

Relative thermal index

SAN

Styrene acrylonitrile copolymer

SARS

Severe acute respiratory syndrome

SED

Surface-conduction electron emitter display

SIM

Subscriber identity module

SLA

Stereolithography

STN

Super-twisted nematic or supertwist

T260

The time at 260 ºC before decomposition occurs

TAV

Total asset visibility

Td

Thermal decomposition temperature

TFT

Thin film transistor(s)

Tg

Glass transition point

TI

Texas Instruments(s)

TN

Twisted nematic

TPE

Thermoplastic elastomer(s)

TPE-O

Thermoplastic polyolefin

TPE-S

Thermoplastic styrene copolymer elastomer

UDC

Universal Display Corporation

UHMW-PE Ultra-high molecular weight polyethylene UL

Underwriter’s Laboratory

USB

Universal serial bus

UV

Ultraviolet

VoIP

Voice over internet protocol

WEEE

Waste Electrical and Electronic Equipment

XPS

Crosslinked polystyrene

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ISBN-10: 1-84735-006-2 ISBN-13: 978-1-84735-006-0

Smithers Rapra Limited Smithers Rapra Limited is a leading international organisation with over 80 years of experience providing technology, information and consultancy on all aspects of rubbers and plastics. Smithers Rapra Limited was formed in 2006 when Rapra Technology became part of The Smithers Group. Rapra has extensive processing, analytical and testing laboratory facilities and expertise, and produces a range of engineering and data management software products, and computerised knowledge-based systems. Rapra also publishes books, technical journals, reports, technological and business surveys, conference proceedings and trade directories. These publishing activities are supported by an Information Centre which maintains and develops the world’s most comprehensive database of commercial and technical information on rubbers and plastics.

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