Patent ID: 7261843
Filing Date: 2007-08-28
Classification: C08G,C09D,Y10T

Abstract:
1. A photochromic article comprising: (a) a rigid substrate comprising paper, glass, ceramic, wood, masonry, textile, metal and/or organic polymeric material, (b) a photochromic organic polymeric coating appended to at least a portion of at least one surface of said substrate, said polymeric coating comprising a photochromic amount of at least one photochromic material, wherein said polymeric coating comprises photochromic polyurethane-based coatings, photochromic polyurea urethane-based coatings, photochromic poly(meth)acrylic-based coatings, photochromic aminoplast coatings, and/or photochromic epoxy resin-based coatings, and (c) a transparent coating comprising a thermally cured thermoset polymer superimposed on said photochromic polymeric coating, said transparent coating being harder than said photochromic organic polymeric coating, wherein said thermoset polymer comprises (a) a thermosetting polyurethane; (b) a thermoset polysiloxane polymer; and/or (c) a thermoset material prepared from (1) a liquid crosslinkable composition comprising a polyepoxide and a polyacid curing agent; (2) a crosslinkable composition comprising (i) a material containing a plurality of carbamate and/or urea functional groups and (ii) an aminoplast crosslinking agent; (3) a crosslinkable composition comprising at least one acrylic polyol, aminoplast and at least one carbamoyl triazine; (4) a powder clear coating composition comprising (i) an epoxy functional acrylic polymer or copolymer as the predominant film-forming polymer and (ii) a polycarboxylic acid crosslinking agent; or (5) film-forming resin compositions comprising a latex emulsion that includes crosslinked polymeric microparticles dispersed in an aqueous continuous phase.