Temporary tattoos turn the body into a touchscreen

Researchers from Germany’s Saarland University computer science center have developed stretchy temporary tattoos to turn the body into a connected interface.

Building on the technology of previous epidermal electronics, SkinMarks prints multiple layers of thin-film sensors on temporary tattoo paper. Developed by researchers from Germany’s Saarland University Department of Computer Science, the ink is heat cured and after applying an adhesive to the tattoo paper, ready for use as an interactive wearable. SkinMarks are stretchy and smaller than most earlier skin-based connected sensors and designed specifically for use on skin of varying textures and on flexible body parts.

A microcontroller is connected to the tattoo via printed traces, and the sensors are activated by various methods of touch – sliding, squeezing and bending. The tattoos can also be used under accessories such as rings and bracelets, which, if conducive, can become touch sensitive themselves. Further development of the technology will focus on continuing to decrease the size and thickness of the tattoos and finding ways to enable other parts of the body, such as permanent tattoos, hair, tan lines and other types of jewelry, to work with the flexible sensors.

Wearables are becoming ever smaller, more user friendly and well designed. Another temporary tattoo project uses a gold-leaf circuit board for connectivity, and with a signal-emitting ring, the skin around a smart watch can also be used as a touchscreen. How will users disconnect once most garments, accessories and even body parts become integrated into the smart communications network?