Polymerizable composition for optical material, optical material and method for producing optical material

Abstract

Disclosed is a polymerizable composition for o an optical material containing tolylene diisocyanate, hexamethylene diisocyanate, and one or more polythiol compounds selected from the group consisting of 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 4,8-, 4,7- or 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, pentaerythritol tetrakismercaptoacetate, pentaerythritol tetrakismercaptopropionate, 2,5-bis(mercaptomethyl)-1,4-dithiane, bis(mercaptoethyl)sulfide, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 4,6-bis(mercaptomethylthio)-1,3-dithiane and 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane.

1 . A polymerizable composition for an optical material comprising tolylene diisocyanate, hexamethylene diisocyanate, and one or more polythiol compounds selected from the group consisting of 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 4,8-, 4,7- or 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, pentaerythritol tetrakismercaptoacetate, pentaerythritol tetrakismercaptopropionate, 2,5-bis(mercaptomethyl)-1,4-dithiane, bis(mercaptoethyl)sulfide, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 4,6-bis(mercaptomethylthio)-1,3-dithiane and 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane. 
     
     
         2 . The polymerizable composition for an optical material as set forth in  claim 1 , further comprising at least one polyisocyanate compound other than tolylene diisocyanate and hexamethylene diisocyanate and selected from the group consisting of an aliphatic polyisocyanate compound, an alicyclic polyisocyanate compound, an aromatic polyisocyanate compound and a heterocyclic polyisocyanate compound. 
     
     
         3 . An optical material obtained by curing the polymerizable composition for an optical material as set forth in  claim 1 . 
     
     
         4 . A method for producing an optical material, the method comprising the step of curing the polymerizable composition for an optical material as set forth in  claim 1 . 
     
     
         5 . The method for producing an optical material as set forth in  claim 4 , in which said optical material is formed by cast polymerization of said polymerizable composition.