| 摘要 |
PURPOSE:To provide the resin which is colorless and transparent, and has a high refractive index and high Abbe number by bringing specific dithiols and prescribed compd. into reaction. CONSTITUTION:The title resin is prepd. by bringing >=1 kinds of the dithiols expressed by formula and the compd. (A) having >=2 reactive unsatd. groups per 1 molecule into reaction. In formula, R1, R3 denote H, 1 to 3 C alkyl, etc.; (n) denotes 1 to 3; 1, 4-benzene dithiol, etc., are usable as the compd. expressed by formula. Polyisocyanate (e.g.: 2, 4-tolylene diisocyanate), polyvalent allyl compd., etc., are preferably used for the compd. A. The lens is formed by adding a polymn. initiator, etc., at need to the dithiols of the formula and the compd. A, injecting the mixture into a desired mold and gradually heating the same. |
