The present invention provides a sulfonate of the formula (I): ##STR1##

wherein Q¹, Q², Q³, Q⁴ and Q⁵ each independently represent hydrogen, alkyl having 1 to 16 carbon atoms, alkoxy having 1 to 16 carbon atoms, halogen, aryl having 6 to 12 carbon atoms, aralkyl having 7 to 12 carbon atoms, cyano, sulfide, hydroxy, nitro or a group of the formula (I)

wherein X represents alkylene and at least one —CH₂— in the alkylene may be substituted by —O— or —S—, and Cy¹ represents alicyclic hydrocarbon having 3 to 20 carbon atoms,

and A⁺ represents a counter ion, with the proviso that at least one of Q¹, Q², Q³, Q⁴ and Q⁵ is the group of the formula (I). The present invention also provides a chemical amplification type positive resist composition comprising a sulfonate of the formula (I) and resin which contains a structural unit having an acid labile group and which itself is insoluble or poorly soluble in an alkali aqueous solution but becomes soluble in an alkali aqueous solution by the action of an acid.