HIGH-REFRACTIVE-INDEX RESIN MATERIAL

PURPOSE: To obtain a resin material having a high refractive index, low disper sion, a low specific gravity and improved impact resistance by polymerizing and curing a polymerizable composition containing specified unsaturated monomers by the action of heat and/or actinic radiation. CONSTITUTION: A mixture of 10-99 pts.wt. urethane-bond- or thioether-bond- containing unsaturated monomer represented by formula I (R is H or CH ; and R is a group of any one of formulas II-VI) with 99-1 pt.wt. compound having at least one ethylenically unsaturated bond in the molecule is mixed with 0.01-5wt.% photopolymerization initiator or heat polymerization initiator. The obtained polymerizable mixture is heated to 20-150 deg.C for 1-30hr or is irradiated with an actinic radiation at a dose of 0.01-300J/m to obtain a polymer being a high-refractive-index resin material having a refractive index of 1.55 or above, an Abbe's number of 30 or above and a specific gravity of 1.35 or below.