... sunlight or UV light 2.Change form :transparent --vivid color --transparent 3.SGS,MSDS TEST 1.photochromic pigment :Under ... Ultraviolet light or sunlight .color change from white color or very light color to RED ,YELLOW,BLUE ,PRUPLE color .Once away Ultraviolet light ... process can repeat again and agian .2.Basic color : Red ,Yellow, Blue ,Purple (after changing color form )3. Change form : White to ...