Patent ID: 8278030

Claim:
A sulfonium salt represented by formula (1): wherein R 1 is a group represented by formula (2); R 2 and R 3 each represent an aryl group having 6 to 30 carbon atoms, a heterocyclic hydrocarbon group having 4 to 30 carbon atoms, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an alkynyl group having 2 to 30 carbon atoms, wherein some hydrogen atoms of the aryl group, the heterocyclic hydrocarbon group, the alkyl group, the alkenyl group, or the alkynyl group may be substituted with a substituent (t); S represents a sulfur atom; and X − represents a monovalent polyatomic anion: wherein R 4 to R 6 each represent an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylthiocarbonyl group, an acyloxy group, an arylthio group, an alkylthio group, an aryl group, a heterocyclic hydrocarbon group, an aryloxy group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a hydroxy(poly)alkyleneoxy group, an amino group, a cyano group, a nitro group, or a halogen atom; k, m, and n represent the number of R 4 , the number of R 5 , and the number of R 6 , respectively; k is an integer of 0 to 4; m is an integer of 0 to 3; n is an integer of 0 to 4; A is a group represented by —S—, —O—, —SO—, —SO 2 —, or —CO—; O represents an oxygen atom; and S represents a sulfur atom.