Patent ID: 7001706

Claim:
A sulfonate of the formula (I): wherein A + represents a counter ion and wherein Q 1 , Q 2 , Q 3 , Q 4 and Q 5 each independently represents a hydrogen, an alkyl having 1 to 16 carbon atoms, an alkoxy having 1 to 16 carbon atoms, a halogen, an aryl having 6 to 12 carbon atoms in which at least one hydrogen may be substituted by an alkyl, a cycloalkyl, an alkoxy, a hydroxyl or a halogen, an arylalkyl having 7 to 12 carbon atoms in which at least one hydrogen on an aryl ring may be substituted by an alkyl, a cycloalkyl, an alkoxy, a hydroxyl or a halogen, a cyano, a mercapto, an alkylthio having 1 to 16 carbon atoms, a hydroxy, a nitro or a group of the formula (I′) —COOR (I′) wherein R represents an aryl having 6 to 12 carbon atoms, a group of the formula (II′) or a group of the formula (II″) wherein R 1 and R 2 each independently represents an alkyl having 1 to 12 carbon atoms, a cycloalkyl having 3 to 12 carbon atoms, an arylalkyl having 7 to 12 carbon atoms or an aryl having 6 to 12 carbon atoms, and at least one hydrogen on an aryl ring in the arylalkyl or in the aryl may be substituted by an alkyl, a cycloalkyl, an alkoxy, a hydroxyl or a halogen, or R 1 and R 2 bond to form a monocyclic or polycyclic hydrocarbon group together with adjacent —C(R a )—, R a represents an alkyl having 1 to 8 carbon atoms, and —CH 2 — in the alkyl except the one at the terminal position may be substituted by —CO—, —O— or —S—, and R 3 and R 4 each independently represents a hydrogen, an alkyl having 1 to 12 carbon atoms, a cycloalkyl having 3 to 12 carbon atoms, an aryl having 6 to 12 carbon atoms, an arylalkyl having 7 to 12 carbon atoms, at least one hydrogen on the aryl ring in the aryl or in the arylalkyl may be substituted by an alkyl, a cycloalkyl, an alkoxy, a hydroxyl or a halogen, or R 3 and R 4 bond to form an monocyclic or polycyclic hydrocarbon group together with adjacent —CH—, with the proviso that at least one of Q 1 , Q 2 , Q 3 , Q 4 and Q 5 is a 1-alkylcycloalkyloxycarbonyl group.