Abstract: A molded or formed product obtained by molding or forming a resin composition comprising (A) at least one vinyl cyclic hydrocarbon polymer selected from the group consisting of hydrogenated products of aromatic vinyl polymers, vinylcyclohexene polymers or hydrogenated products thereof, and vinylcyclohexane polymers, and (B) at least one substance selected from the group consisting of compounding additives incompatible with the polymer, organic compounds having at least one alcoholic hydroxyl group and at least one ether linkage, and organic compounds having at least one alcoholic hydroxyl group and at least one ester linkage, wherein the initial light transmittance (a) of the molded or formed product at an optional wavelength within a range of 400 to 800 nm and the light transmittance (b) of the molded or formed product after the molded or formed product is held for 1,000 hours in an atmosphere of 65° C.

Abstract: A molding material for plastic lenses, comprising a hydrogenated product of an aromatic vinyl polymer, wherein the hydrogenated product of the aromatic vinyl polymer has properties that the hydrogenation rate of aromatic rings is at least 97%, the weight average molecular weight (Mw) is within a range of 50,000 to 500,000, and the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is at most 2.5, a plastic lens obtained by molding the molding material, novel hydrogenated products of aromatic vinyl polymers, which are suitable for use as molding materials, and a production process thereof.

Abstract: A hydrogenated product of an aromatic vinyl polymer, wherein the hydrogenation rate of the aromatic rings thereof is at least 97%, a ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is at most 2.0, the weight average molecular weight (Mw) is 100,000 to 300,000, and the content of a component having a molecular weight (M) of at most 10,000 is at most 2% by weight based on the total weight of the polymer; a hydrogenated product of an aromatic vinyl polymer, wherein the content of foreign matter having a particle diameter of at least 0.5 &mgr;m in the hydrogenated polymer is at most 3.0×104 particles/g; and a substrate for information recording media obtained by molding a resin material containing a hydrogenated product of an aromatic vinyl polymer, wherein the hydrogenation rate of the aromatic rings thereof is at least 97%, a :ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is at most 2.

Abstract: A molded or formed product obtained by molding or forming a resin composition comprising (A) at least one vinyl cyclic hydrocarbon polymer selected from the group consisting of hydrogenated products of aromatic vinyl polymers, vinylcyclohexene polymers or hydrogenated products thereof, and vinylcyclohexane polymers, and (B) at least one substance selected from the group consisting of compounding additives incompatible with the polymer, organic compounds having at least one alcoholic hydroxyl group and at least one ether linkage, and organic compounds having at least one alcoholic hydroxyl group and at least one ester linkage, wherein the initial light transmittance (a) of the molded or formed product at an optional wavelength within a range of 400 to 800 nm and the light transmittance (b) of the molded or formed product after the molded or formed product is held for 1,000 hours in an atmosphere of 65° C.

Abstract: A molded or formed product obtained by molding or forming a resin composition comprising (A) at least one vinyl cyclic hydrocarbon polymer selected from the group consisting of hydrogenated products of aromatic vinyl polymers, vinylcyclohexene polymers or hydrogenated products thereof, and vinylcyclohexane polymers, and (B) at least one substance selected from the group consisting of compounding additives incompatible with the polymer, organic compounds having at least one alcoholic hydroxyl group and at least one ether linkage, and organic compounds having at least one alcoholic hydroxyl group and at least one ester linkage, wherein the initial light transmittance (a) of the molded or formed product at an optional wavelength within a range of 400 to 800 nm and the light transmittance (b) of the molded or formed product after the molded or formed product is held for 1,000 hours in an atmosphere of 65° C.

Abstract: A molded or formed product obtained by molding or forming a resin composition comprising (A) at least one vinyl cyclic hydrocarbon polymer selected from the group consisting of hydrogenated products of aromatic vinyl polymers, vinylcyclohexene polymers or hydrogenated products thereof, and vinylcyclohexane polymers, and (B) at least one substance selected from the group consisting of compounding additives incompatible with the polymer, organic compounds having at least one alcoholic hydroxyl group and at least one ether linkage, and organic compounds having at least one alcoholic hydroxyl group and at least one ester linkage, wherein the initial light transmittance (a) of the molded or formed product at an optional wavelength within a range of 400 to 800 nm and the light transmittance (b) of the molded or formed product after the molded or formed product is held for 1,000 hours in an atmosphere of 65° C.