This is a special color for textiles: you first apply the color to the textile (which is colorless in the beginning), put a negative on top of it and then expose it to sunlight.
After some time, the color develops, you remove the negative and wash the textile with a special detergent. Then you have the motive in the color you used.
On the pictures, you see two steps of the process: the inverted picture on a foil, attached to the T-shirt (which was prepared with Lumi color), and the shirt after the developing in the light.
I was a little bit disappointed with the result; after the washing, most of the constrast disappeared, and the color distributed over the other textiles in the washing machine.
Next time I would change the following things:
- make sure that it is a bright, sunny day (we only had a cloudy day) or a strong UV light (did anyone try to develop it in a tanning salon?)
- wash it more than one time before drying it in the sun