Interference pigment flakes and foils are provided which have luminescent and color-shifting properties. The pigment flakes can have a symmetrical coating structure on opposing sides of a core layer, can have an asymmetrical coating structure with all of the layers on one side of the core layer, or can...http://www.google.de/patents/US6572784?utm_source=gb-gplus-sharePatent US6572784 - Luminescent pigments and foils with color-shifting properties
