Solarfast uv reactive paints black a clever uv sensitive paint apply to fabric or paper using a brush sponge or inking roller blot excess paint thoroughly then cover with an opaque design drawn or printed onto acetate or any object that casts a shadow and expose to uv light the light fixes the dye colour will not develop in the shaded areas and the undeveloped dye can be washed out with solarfast wash out can also be used for printing when mixed with solarfast thickener 236ml bottles