Patent ID: 7316875
Filing Date: 2008-01-08
Classification: G03C,Y10S

Abstract:
1. An image forming medium, comprising a polymer; and a photochromic compound containing chelating groups embedded in the polymer; and a metal salt; wherein molecules of the photochromic compound are chelated by a metal ion from the metal salt; wherein the photochromic compound comprises at least one of a spiropyran compound, spirooxazine, thiospiropyran, a benzo compound, naphthopyran, stilbene, azobenzene, bisimidazol, spirodihydroindolizine, quinine, perimidinespirocyclohexadienone, viologen, fulgide, fulgimide, diarylethene, hydrazine, anil, and aryl thiosulfonate; wherein the chelating group is at least one of carboxylic acid, primary, secondary and tertiary amino groups, ester groups, hydroxyl, ether groups, heteroaromatic groups, sulfonic acid, ketone, thioalcohol, and thioether; and wherein the image forming medium further comprises at least one salt of a metal with an oxidation state of +1 or +3.