URETHANE RESIN PLASTIC LENS

摘要

PURPOSE:To provide a titled lens having high transparency and impact resistance by using an urethane resin obtd. by addition polymn. of the product of reaction of an isocyanate compd. and an unsatd. compd. contg. a hydroxy group as a blank material and providing prescribed optical properties. CONSTITUTION:An urethane resin obtd. by addition polmn. of the product of reaction of an isocyanate compd. and an unsatd. compd. contg. a hydroxyl group is used as a blank material. The various properties of the resultant plastic are changed by selecting the amts. of compounding of both components, reaction temp. and reaction time variously and therefore the lens is made to have refractive index ND=1.45-1.70 (values at 20 deg.C) and Abbe number nu=35-60 by selecting these, whereby the lens having high transparency and impact resistance is obtd.