Patent 7682531 was granted and assigned to Hoya on March, 2010 by the United States Patent and Trademark Office.
A method of manufacturing an optical member by mixing isocyanate terminal prepolymer component (A) and aromatic diamine component (B), and immediately after mixing, casting a mixture into a casting mold to obtain a molded article. A method of manufacturing a plastic lens by mixing said components (A) and (B), immediately after mixing, casting a mixture into a casting mold and polymerizing it to obtain a molded article. A gasket for molding plastic lenses comprised of a cylindrical member. A casting mold for molding plastic lenses using this gasket and a monomer casting jig.