PROCESS FOR PREPARING MOLDED OPTICAL ARTICLES

摘要

Provided is a process for preparing a molded optical article that is essentially free of optical defects. The process comprises: a) introducing each of two separate reactive components A and B from separate supply vessels into a mixing chamber having a volume of 200 ml to 2000 ml; b) mixing the components together in the mixing chamber for a period of 50 to 200 seconds to form a reaction mixture; c) injecting the reaction mixture at a temperature of up to 130° C. into a mold; d) holding the reaction mixture in the mold at a temperature and for a time sufficient to essentially cure the reaction mixture and form a molded optical article; and e) releasing the article from the mold. The process is particularly suitable for preparing polythiourethane lenses with high yield, high transparency, very low haze, low flow lines and low inclusions.