| 摘要 |
PROBLEM TO BE SOLVED: To obtain a curable composition which can give an optical material having a low specific gravity, excellent optical properties including a high refractive index and a high Abbe's number, and improved handleability at a near room temperature by mixing a specified polythiol with a compound copolymerizable therewith. SOLUTION: A cyanuric halide of formula I (wherein X is Cl, Br, or I) is reacted with 3-30 mol, per mol of the cyanuric halide, of a dithiol at -20 to 150 deg.C to obtain a polythiol of formula II (wherein (n) is 0-5). 5-90 wt.% of this polythiol is mixed with 10-95 wt.% least one copolymerizable compound selected among a polyisocyanate compound, a polyisothiocyanate compound, an isocyanato-containing isothiocyanate compound, a monomer having a polymerizable unsaturated bond, an epoxy compound, an epithio compound, and a monomer having a plurality of thiol groups and being other than the polythiol of formula II. |
