Pouring into a mold polymerization method null of sulfur-containing urethane resin make

摘要

There is here provided a casting polymerization process for preparing a sulfur-containing urethane resin lens by which the lens can be easily released from a lens matrix and by which the surface of the lens can have a high transparency and a good surface accuracy, the aforesaid process being characterized in that in casting-polymerizing a polyisocyanate having two or more isocyanate groups and a polythiol having two or more thiol groups in the lens matrix made of glass or metal, the surface active agent comprising one or more selected from the group consisting of fluorine and silicon series nonionic surface active agents, alkyl quaternary ammonium salts and acidic phosphate esters is previously added, as an internal release agent, to the mixture of the polyisocyanate and the polythiol.