Method for manufacturing monosulfonium salt, cationic polymerization initiator, curable composition, and cured product

Abstract

A monosulfonium salt in which very little unreacted raw material remains, which has a purity of at least 96%, and which has one sulfonio group in its molecule is manufactured without a refining step. After (a) an aryl compound, (b) a sulfoxide compound, (c) a dehydrating agent, and (d) a BF 4 , PF 6 , AsF 6 , or SbF 6 salt of an alkali metal or an alkaline earth metal are introduced into a reaction system, (e) an inorganic acid is added, so that the aryl compound (a) and the sulfoxide compound (b) are subjected to dehydration condensation.

1 - 3 . (canceled) 
     
     
         4 . A cationic polymerization initiator comprising a monosulfonium salt represented by the general formula (1): 
       
         
           
           
               
               
           
         
         wherein Ar denotes an optionally substituted aryl group; each of R 1  and R 2  denotes the same or different, optionally substituted heterocyclic group or hydrocarbon group; and X −  denotes BF 4   − , PF 6   − , AsF 6   − , or SbF 6   − , and 
         wherein the monosulfonium salt is manufactured by introducing (a) an aryl compound, (b) a sulfoxide compound, (c) a dehydrating agent, and (d) a BF 4 , PF 6 , AsF 6 , or SbF 6  salt of an alkali metal or an alkaline earth metal into a reaction system, followed by introduction of (e) an inorganic acid so that the aryl compound (a) and the sulfoxide compound (b) are subjected to dehydration condensation. 
       
     
     
         5 . A curable composition comprising the cationic polymerization initiator described in  claim 4  and a cationically polymerizable compound, wherein the cationic polymerization initiator consists of 97% by mass or more of the monosulfonium salt and 3% by mass or less as a total of an aryl compound and a sulfoxide compound. 
     
     
         6 . A cured material formed by curing of the curable composition described in  claim 5 .