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Abstract

Photochromic coating compositions for synthetic resin ophthalmic lenses to impart photochromic properties to the lenses are provided. The photochromic coating composition includes an organic silicon compound to impart a surface hard coating and a photochromic material dispersed in the hard coat to impart photochromic properties. The photochromic materials may include compounds including the molybdic acid amine group, dithizone-mercury polymers, halogenated silver or copper, and a benzopyrylospiran compound. The coating composition is prepared by dispersing the photochromic material in a silicon hard coating composition. The coating composition may be coated on the surface of a synthetic resin lens by dipping, spraying, spin coating, flow coating and the like and then dry-heated to be cured. The coating composition is applied in thicknesses from about 1 to 30 microns. The synthetic resin lenses which may be coated are transparent resins, such as polycarbonate resins, acryl resin, CR-39 resins, polystyrene and the like.

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First Claim