Abstract: The present invention relates to resin useful in preparing plastic lenses having a high refractive index comprising reacting an aliphatic polyisocyanate compounds having at least one sulfur atom with one or more of active hydrogen compounds selected from the group consisting of a polyol, a polythiol having sulfur atoms only in a mercapto groups, and a polythiol having at least one sulfur atom other than in the mercapto groups; lenses containing the above-mentioned resin; and a method for the preparation thereof characterized by adding an internal release agent to the mixture of the above-mentioned raw materials in casting lenses from the resin; and lenses obtained by this method.

Abstract: A process for producing a plastic lens having a high refractive index and profile regularity which includes forming a mixture of one or more of sulfur-containing aromatic polyisocyanate compounds, one or more of active hydrogen compounds selected from the group consisting of polyol compounds and polythiol compounds, and at least one internal mold releasing agent. Then subjecting the resulting mixture to casting polymerization, to form the plastic lens.

Abstract: Disclosed herein are a novel and highly refractive S-alkyl thiocarbamate base resin useful in preparing lenses and a process for producing the resin comprising reacting one or more of polyisocyanate compounds and one or more of mercapto compound having at least one hydroxyl group, a plastic lens made of the resin, and a process for making a plastic lens of high profile regularity from the resin by using internal mold releasing agents in the casting polymerization process.

Abstract: A novel compound, 4-(4-hydroxyphenyl)-3-cyclohexene-1-ol, and a novel preparation process of 4,4'-biphenol by using the novel compound as the raw material.4-(4-Hydroxyphenyl)-3-cyclohexene-1-ol can be obtained by conducting a thermal decomposition reaction of 4,4-bis(4-hydroxyphenyl)cyclohexanol. 4,4'-Biphenol can be industrially manufactured by conducting a dehydrogenation reaction of 4-(4-hydroxyphenyl)-3-cyclohexene-1-ol.

Abstract: Polyurethane base lens resins obtained by reacting one or more of sulfur-containing polyisocyanates compound with one or more of sulfur-containing polyols, and polyurethane base lenses comprising these resins are disclosed.A method for preparing polyurethane base lenses which comprises adding internal mold releasing agents to the mixture of the above polyisocyanates and polyols prior to casting polymerization is also disclosed.

Abstract: A novel compound, 4-(4-hydroxyphenyl)-3-cyclohexene-1-ol, and a novel preparation process of 4,4'-biphenol by using the novel compound as the raw material.4-(4-Hydroxyphenyl)-3-cyclohexene-1-ol can be obtained by conducting a thermal decomposition reaction of 4,4-bis(4-hydroxyphenyl)cyclohexanol. 4,4'-Biphenol can be industrially manufactured by conducting a dehydrogenation reaction of 4-(4-hydroxyphenyl)-3-cyclohexene-1-ol.

Abstract: A novel compound, 4-(4-hydroxyphenyl)-3-cyclohexene-1-ol, and a novel preparation process of 4,4'-biphenol by using the novel compound as the raw material.4-(4-Hydroxyphenyl)-3-cyclohexene-1-ol can be obtained by conducting a thermal decomposition reaction of 4,4-bis(4-hydroxyphenyl)cyclohexanol. 4,4'-Biphenol can be industrially manufactured by conducting a dehydrogenation reaction of 4-(4-hydroxyphenyl)-3-cyclohexene-1-ol.