Patent ID: 7074738

Claim:
A curing accelerator to be mixed into a curable resin composition for promoting the curing reaction of the curable resin composition, wherein the curing accelerator comprises trisubstituted phosphoniophenolate or a salt thereof, wherein the trisubstituted phosphoniophenolate is represented by the following general formula (1): wherein R 1 , R 2 and R 3 are the same as or different from one another, and each represents a substituted or unsubstituted monovalent organic group containing at least one aromatic ring; and Ar represents (i) an unsubstituted phenylene group or (ii) a phenylene group substituted with a single substituent, said substituent not being a hydroxyl group; further wherein the oxyanion-O âˆ’ is located in an ortho or meta position relative to the phosphorus atom.