Before flexible electronic devices finally enter our lives, scientists have to create microcircuits that have the ability to stretch. Panasonic's team has made significant progress in developing a soft, flexible polymer resin film combined with transparent electrodes and a conductive paste.
Due to the stretching property of the material, the substrate can grow 2, 5 times, and then return to its original state. Also, the resin has a thermosetting property. This means that it only reacts once to heat during manufacture. Further heating will not melt it.
The ability to withstand such stresses and subsequent "respites" is due to the special three-dimensional "cross-linked" structure of the resin, which distributes mechanical stress evenly. In comparison, most rubbers lose their properties after a few stretches.
Conductive electrodes are made from a layer of carbon nanotubes "adhered" to the resin. Unlike indium and tin, nanotube material does not crack and does not lose electrical conductivity.
The electrode samples for the circuits are made from a paste made of the same polymer as the substrate, only mixed with silver. This explains the resistance to mechanical deformation and conductivity retention.