- “We learned that devices that can be worn for a week or longer for continuous monitoring were needed for practical use in medical and sports applications,” says Professor Takao Someya at the University of Tokyo’s Graduate School of Engineering whose research group had previously developed an on-skin patch that measured oxygen in blood.
- However, although the ultrathin films and rubber sheets used in these devices adhere and conform well to the skin, their lack of breathability is deemed unsafe for long-term use: dermatological tests show the fine, stretchable materials prevent sweating and block airflow around the skin, causing irritation and inflammation, which ultimately could lead to lasting physiological and psychological effects.
- Wearable electronics that monitor heart rate and other vital health signals have made headway in recent years, with next-generation gadgets employing lightweight, highly elastic materials attached directly onto the skin for more sensitive, precise measurements.
- A hypoallergenic electronic sensor can be worn on the skin continuously for a week without discomfort, and is so light and thin that users forget they even have it on, says a group of researchers at the University of Tokyo and their collaborators.
- The group also evaluated the permeability, with water vapor, of the nanomesh conductor—along with those of other substrates like ultrathin plastic foil and a thin rubber sheet—and found that its porous mesh structure exhibited superior gas permeability compared to that of the other materials.
- The device can be applied by spraying a tiny amount of water, which dissolves the PVA nanofibers and allows it to stick easily to the skin—it conformed seamlessly to curvilinear surfaces of human skin, such as sweat pores and the ridges of an index finger’s fingerprint pattern.