New research published in ACS Applied Materials & Interfaces reports the development of ultrathin, stretchable electronics that can be easily transferred to 3D objects or made to adhere to human skin. The paper’s authors say these flexible electronics could improve man-machine interfaces in a variety of ways.
The researchers fabricated a ∼5 μm thick circuit by printing the pattern over a temporary tattoo paper using a desktop laser printer. They then coated the circuit with a silver ink and eutectic gallium–indium (EGaIn) liquid metal alloy. The resulting “Ag–In–Ga” traces are highly conductive and maintain low electrical resistivity as the circuit is stretched to conform to nondevelopable 3D surfaces.
The authors write that this material could have a number of practical applications, such as creating an interactive circuit with touch buttons, transferring light-emitting diodes to the 3D-printed shell of a robotic prosthetic hand, making tattoos that could be used to acquire an electromyography signal from human skin, and transferring a proximity measurement skin over a 3D surface.
This video shows how these circuits could be used to help machines and humans interact.