Versatile camouflage coating of photochromic pigments

Based on photochromism of a diarylethene species, we introduced an easy but highly effective bar-coating method of a photochromic ink including shell type of photochromic pigments and UV curable epoxy resin, reversibly presenting change color in response to ultraviolet (UV) light. By using mask patterns for bar-coating, different patterns were successfully coated on various types of surfaces such as wood, glass, general concrete wall and even curved surfaces. Besides, in order to increase mechanical stability of the coating, thin layer including acrylate chemicals is further coated on the patterns. Finally, camouflage coating applications for encryption display films were successfully demonstrated.