WearTec

Warning to all the wearable gadget fans, this one does not require batteries and does not seem “technical” at all at first glance.
Caribongo designes clothes and more importantly prints and motives that are applied to the fabric using a special, photochromic ink.
The photochromic ink makes the whole product stand out from other clothing items. Because of it the motive appears gray, but walk into sun light and all of a sudden the motive is colored.

Their website explains how photochromic ink works:

All our products shown on this website use our unique photochromic technology.

Photochromic is the correct term for sun -or- UV activated pigments.

In short Ultra-violet (UV) light changes the molecular structure of the photochromic inks and makes them absorb color. The inks undergo a temporary physical change in which the molecules change state and appear colored.

When the UV source (sunlight) is removed, the molecules return to their original state and the inks lose their color.

Pretty cool and a “low impact” piece of wearable technology. My only concern is whether the effect will still work after a few washes.

[via Tshirt Island]