Low-cost printing of electronics

Materials World magazine
,
1 Dec 2009
A printed electronic substrate

A UK printed media firm claims to have developed a low-cost way of
applying electronic circuitry to packaging, which could turn an
ordinary carton into an interactive game.

The technique, discovered by Cambridge-based company Novalia, uses
existing high-volume printing processes, such as screen, offset and
flexography, to pattern metallic conductive tracks onto substrates. The
process is said to be as easy as adding a barcode.

Dr Kate Stone, CEO of the company, believes that this could transforms
consumer packaging. ‘Many companies in this field borrow some form of
printing and take it back into an electronics environment’, she
explains. ‘But we are the first people to use conductive inks on
commercial presses, taking printed electronics to the printers
themselves, who have the manufacturing facilities and a validated route
to market.’

The concept uses a compact, self-contained printed elect-ronics control
module consisting of a power source, integrated circuits for input/
output control and interaction flow, and a sound transducer.

Novalia’s designers incorporate lines into the graphics of the product,
which form the circuit to drive user interaction. These will be printed
with conductive inks – silver, carbon or polymer depending on the print
process. The specific nature of the interaction will depend on the
programing of the chip. Sensors, LEDs and audio devices can be added,
but no extra wiring is required.

‘At the moment the controller is a couple of millimetres thick, but
there is always somewhere in a package to put something like that,’
explains Stone, adding that the company eventually hopes to shrink it
to the size of a postage stamp.

Stone envisages a take-away meal carton turning into a toy with lights
and sounds, or a pharmaceutical package that highlights safety
precautions.

‘Printing has very low tooling cost,’ she points out. ‘The value is
that the whole printed surface is the user interface. We’re not trying
to put a display on a cereal packet, we are trying to make a printed
product interactive.’

‘We have working examples of this concept, such as a carton that
becomes a toy fire engine’, says Stone. ‘Touch various parts of the
image and the fire engine makes a different noise. Once [the demo
model] has passed through a manufacturing phase, it could be produced
on a million boxes per week, in just one factory.’

The company is working with battery developer Blue Spark Technologies,
based in Westlake, USA, to achieve a cost-effective power source. Blue
Spark claims that their carbon-zinc batteries are thin, flexible and
disposable, meeting the RoHS directive.

Further information: Novalia and Blue Spark Technologies

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