Previously restricted to biohackers, the use of LEDs and invasive surgical procedures and often dedicated solely to aesthetics, a practical, temporary and facilitated method of applying illuminated tattoos was developed by scientists at University College London (UK) and of the Istituto Italiano di Tecnologia. Among the researchers’ objectives is the construction of a medical tool capable of issuing different alerts when combined with other wearable solutions.
In an article published in the magazine Advanced Electronic Materials, those responsible for the novelty explain that it carries the organic light-emitting diode technology present in devices such as the latest iPhones and folding screens.
Furthermore, due to the flexibility of the largest organ in the human body, in which they intend to test the creation soon, and the folds generated by movements, the OLED proved to be the best option for their purposes.
In short, an extremely thin layer of an electroluminescent polymer that glows after receiving a charge, just 2.3 micrometers thick, about a third the diameter of a red blood cell, the inventors point out, “fills in” a pair of electrodes and is on top of an insulating layer.
The result, in turn, is pasted onto temporary tattoo paper using a ‘cheap’ and large-scale reproducible printing process. In total, the equipment is 76 nanometers thick.
“This is just the first step. Future challenges will include encapsulating OLEDs as much as possible to prevent them from rapidly degrading through contact with air, as well as integrating the device into a battery or supercapacitor,” says Franco Cacialli , senior author of the article.
One step at a time
Also according to the team, the new OLED tattoos make use of the wet transfer process of temporary tattoos designed for children – easily washed off with soap and water when no longer needed or desired.
The possibilities, claim the creators, are many. Bright illustrations and light-emitting nails, for example, are not out of the question, but in the health area, electronics can even indicate changes in body conditions, dehydration of athletes and optimize light therapies in the fight against cancers.
“Tattoo electronics is a rapidly growing field of research. At the Istituto Italiano di Tecnologia, we have already developed electrodes that we tattoo on people’s skin and are used to carry out diagnostic tests, such as electrocardiograms,” said Virgilio Mattoli.
Limitations, of course, exist for now. The group emitted only green light on a glass panel, a plastic bottle, an orange and a paper package. Not on human skin yet.
Finally, in the future, it is expected that all colors of the RGB spectrum will be displayed and that the technology will eliminate the need for external power supply for additional components.