Panasonic has recently developed a soft, flexible, and stretchable polymer resin insulating film which stretches 2.5 times its length and returns to its original shape. It can be folded and adapts to varying free-form surfaces, as to reducing existing design constraints.
The possibilities for this type of technology could be endless! For an example, it would enable the construction of soft and stretchable electronic devices that are adaptable to various forms such as clothing and the body. This would open the window to many wearable technologies, and make clothing “smart” clothing.
Overcoming the Numerous Challenges
Polyurethane and rubber materials need to overcome challenges associated with adhesion, heat resistance, and the fact that they are brittle. Panasonic’s insulating material, made of thermosetting resin, is, both flexible and stretchable.
Devices implemented on clothing or worn on the body should be made of materials that withstand repeated use and allow no change in mechanical properties even after repeated deformation. In normal circumstances, materials subjected to repeated stretch and restore would tend to degrade in mechanical strength and recovery performance. Going beyond simple softening, Panasonic employed a unique resin design technology that makes optimal use of the characteristic three-dimensional cross-linked structure of thermosetting resin. By relaxing internal stresses arising from stretch, the newly developed insulating material returns to its original shape and withstands repeated use
Usually, copper or other metal wiring would break when its base material stretches or contracts. Due to this problem, it is not easy to use metal wiring to form complex circuits. Furthermore, metal fatigue resulting from deformation makes it difficult to achieve metal wiring that withstands repeated stretch. Panasonic has developed a technology to combine a stretchable resin as a binder with a silver filler. The result is conductive paste that retains a conductive path, hence conductivity, even after stretch and restore.
It will be interesting to see where this technology’s future lies, and how it will evolve over time.