Tattoos are usually permanent, which is exactly what some people later regret. A new type of ink, described by New Scientist, could change that by making tattoos possible to hide on demand. The ink is said to be turned on and off with light, allowing the same design to appear or disappear.
If the technology works as described, it would give wearers control over when their tattoos are visible. That could be useful for professional settings, travel, or simply changing one's mind. The report does not specify how the ink works or when it might be available, but the basic idea is that light triggers a reversible change in visibility.
This is an early-stage concept, and no claims are made about testing or commercial availability. Still, the possibility of a tattoo that can be switched off with light offers a clear alternative to permanent ink.