Patent ID: 8889888

Claim:
A sulfonic acid onium salt compound represented by the following general formula (2) wherein R represents (a) a linear or branched monovalent hydrocarbon group selected from methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, i-octyl group, n-nonyl group, n-decyl group, 2-ethylhexyl group and n-dodecyl group, (b) a monovalent hydrocarbon group having a cyclic or a partially cyclic structure selected from cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, bornyl group, norbornyl group, adamantyl group, pinanyl group, thujyl group, caryl group, camphanyl group, cyclopropylmethyl group, cyclobutylmethyl group, cyclopentylmethyl group, cyclohexylmethyl group, bornylmethyl group, norbornylmethyl group and adamantylmethyl group, (c) an aryl group selected from phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 1-phenanthryl group, or (d) a heterocyclic organic group selected from furyl group, thienyl group, piranyl group, pyrrolyl group, thianthrenyl group, pyrazolyl group, isothiazolyl group, isoxazolyl group, pyrazinyl group, pyrimidinyl group, pyradazinyl group and monocyclic or polycyclic lactone, wherein any of the group selection from (a) to (d) may have a substituent selected from fluorine, chlorine, bromine, iodine, hydroxyl group and thiol group, wherein any of the group selection from (a), (b) and (d) may have an aryl group as a substituent or have a keto group in which two hydrogen atoms on the same carbon in the hydrocarbon group are substituted with one oxygen atom, wherein the group selected form (c) may have an alkyl group as a substituent, and wherein Q + represents a monovalent onium cation.