Peratech is offering a novel and interesting ink that can change its resistance by as much as 16 orders of magnitude when pressed with a finger! This intriguing material is based on a quantum tunnelling composite (QTC) which consists of a polymer (e.g., silicone) and metal nanoparticles (e.g., nickel). Here, the spiked nanoparticles are brought in close proximity when pressed, enabling the current carriers to tunnel across the metallic nanoparticles. When the pressure is released, the spiked nanoparticles come apart again, severing the current path.
Speaking at the IDTechEx Printed Electronics USA 2011 event earlier this month, Peratech revealed how the QTC can be formulated as a transparent, translucent or opaque ink but the attributes do not end here. The QTCs are flexible, can withstand a temperature range of -60 C to 250 C, and support a current of up to 10,000 A!
The immediate application is a switch in which the material goes from being an insulator to being a conductor when pressed. This can bring touch sensing capability to a large array of different substrates and products, including NASA's robotic arms. They can also be printed atop a variety of textiles, bringing touch to our everyday clothing including gloves.
They can also act as transducers, converting mechanical energy into an electrical signal. This could, for example, act as piezoelectric-type detector and monitor the heart beat rate when printed on medical clothes. It could serve as a large-area vibration sensor when printed on various industrial machines. Or it could even be used as fencing attire, sensing the moment of contact!
The applications for this novel product are numerous but some challenges remain too. In particular, the pressure sensitivity must be tamed and accurately controlled. This is because small changes, non-uniformities and/or non-linearity can change the conductivity by several orders of magnitude. There are pending questions regarding the stability and consistency, as well as response time. In general, this is an impressive material and we will be closely following its progress.
Peratech won the award for commercialization at the IDTechEx event after announcing two multi million dollar license deals. For more information, hear Peratech present at Printed Electronics Europe 2012.