| 摘要 |
<p>An optical lens with a high refractive index which comprises, so as to have high heat resistance and excellent dyeability, a sulfurized urethane resin obtained by polymerizing at least one polyisocyanate compound with at least two polythiols and/or sulfurized polyol compounds, wherein the polythiols contain as the essential ingredient a dithiol compound represented by the general formula HS-[-(-CH2-)-nS-]-mH, wherein n is an integer of 1 to 4 and m is an integer of 1 to 3. The lens, when prepared from monomers in which the polythiols contain 3 to 40 mol% di(2-mercaptoethyl) sulfide as an example of the dithiol compound through a given polymerization under heating, attains a refractive index of 1.59 or higher and a heat distortion temperature of 95 °C or higher and has excellent dyeability.</p> |
