US Patent 7087195 Photochromic curable composition and cured articles thereof

There is provided a method of preventing decreases in the developed color density and color fading speed of an organic photochromic compound without lowering the mechanical and optical physical properties such as hardness of a cured product when the cured product which has the organic photochromic compound dispersed in a polymer matrix is obtained. A photochromic cured product is obtained by curing a photochromic curable composition which comprises a polymerizable monomer having a biphenyl skeleton such as p-phenylphenyl methacrylate, a multifunctional polymerizable monomer having no biphenyl skeleton such as a mixture of trimethylolpropane trimethacrylate and triethylene glycol dimethacrylate, and an organic photochromic compound.