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Printed Electronics World
Posted on October 22, 2007 by  & 

Would electronic devices be free of toxic substances if printed?

The media have widely reported the allegation by Greenpeace, following independent tests, that the new iPhone contains toxic substances such as bromine, antimony, lead and chlorine. Reports say that it has been notified that it is in breach of its home state's law. Apple has promised that PVC, a source of chlorine, and flame retardants containing bromine will be banned from all its new products by the end of 2008. Phthalate plasticisers, cited for birth defects, may also have to be removed, or warning labels attached, say reports. After all, young children may chew on the ubiquitous electronics in the average home today. It may be dropped in a fire, thus emitting dangerous fumes, or it may be dropped in food. People do strange things. Then there is the pollution from waste disposal because the final destination of billions of such tiny items is inherently uncontrollable. Greenpeace says that none of this would be a problem under European law however. Apparently the Europeans are more concerned about sending back Chinese toys made with lead paint.
 
Of course, the environmental claims of Apple, with Al Gore sitting on the Board, make it a good target. We make no judgement what Apple is or is not doing but we would note that the electronics industry has a long record of using bromine based PCB flame retardant, lead solders and so on. PVC has almost entirely been removed from electronic products and lead free solders are commonly available. Arsenic and antimony are silicon dopants. Photolithography of silicon chips still involves hydrofluoric acid and polymer substrates may be made using carcinogenic solvents. Lithium appears widely in batteries.
 
 
There is therefore a bigger story here, involving the use and disposal of nasty chemicals in electronics factories, whether or not they reach the consumer in the final product. The environmental arguments, concerning poisons and pollutants, are therefore easy to make against the old electronics. Indeed, open up a talking gift card and you will see that most of the basic technology has not changed significantly for 60 years. The loudspeaker, wires, solder, capacitors, batteries and resistors are much the same.
 
Consumer electronics will mostly be made by printing in the years to come. Therefore an interesting question is whether it will be poisonous either at the level of the factory or the level of the user? Unfortunately, the answer is only "sometimes". Carcinogens often feature in the manufacture of both plastic substrates and plastic inks. Are all the solvents in the inks themselves safe? Just as cadmium has been banned from batteries and other things in some parts of the world, cadmium telluride thin film photovoltaics has landed orders totalling over one billion dollars in the last few months. The argument is that its binding energy is great, so heat, for example, will not easily release cadmium and anyway it is used in architectural features, where there is controlled disposal, and it is usually banned from disposables such as toys. First Solar even argues that its CdTe PV is doing an environmental service by binding up a nasty industrial by product. Cambridge University in the UK researches next generation nanocomposite photovoltaics based on CdTe.
 
 
Lithium is still widely used in the new thin film batteries. Silver ink is very prevalent in printed electronics yet its disposal is controlled in countries such as Germany because, in nano form it is a biocide. That one is curious because it is not in nano form when it is trashed as an electronic circuit. What about phthalates in printed electronics?
 
Perhaps a global trade association will emerge for the new electronics. Perhaps it will restrict membership to those with non poisonous products and processes. To be fully environmental it would have to back those that do not use precious materials either, though that would exclude most players. Such an industry body could acquire the environmental banner and, as a result, huge backing from consumers and governments. Alternatively we could bumble on and tell the world that we are "good in parts". Those were the words used by an English curate a long time ago when he was served a bad boiled egg for breakfast and wanted to be tactful. Thus the English phrase "Good in parts."
 
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Source of top image: www.abcnews.go.com
 

Authored By:

Chairman

Posted on: October 22, 2007

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