Various natural and synthetic surfactants are now used to reduce the surface tension of water and ensure uniform nanomaterials dispersibility for smooth printing and wide application.
Some (at Harvard University and MIT) have developed "biosensitive" inks for temporary patches or for real so-called smart tattoos (printed biosensors).
Once on or in the skin, the ink gives indications of temperature or health status, for example by turning from blue to brown depending on the sugar level in the interstitial fluid (see diabetes), or from purple to pink depending on the pH of the skin and changing intensity according to the salt level.
In addition to the health risks associated with the production/use of nanoparticles, they could encourage an explosion in the marketing of a number of light display devices, as well as so-called "communicating" and/or "smart" surfaces, objects, buildings and vehicles thanks to the ease of printing presence, pressure and temperature sensors on a wide variety of media.
Manufacturers argue that electronics will thus be lightened or even diffuse (the motherboard disappears in favor of printing on structural or exterior parts, replacing screens, microphones, keys, joysticks and buttons) which is presented as a source of savings.