A breakthrough in tattoo technology allows for temporary ink that reacts to ultraviolet light, changing color almost instantly when exposed to a 365-nanometer UV LED. The pigment remains embedded in the skin but fades just as quickly under bright sunlight, offering a reversible alternative to permanent tattoos. Researchers have demonstrated how this method could enable dynamic, erasable body art without invasive procedures. The discovery opens possibilities for medical markings, fashion, or temporary identification that can be altered on demand.
A 365-nanometer ultraviolet LED can switch a tattoo pigment on in about two to three seconds, and bright sunlight erases the color again within seconds, even though the pigment stays in the skin. That ...
