Patent ID: 8906589

Claim:
A salt represented by the formula (I): wherein R 1 and R 2 each independently represent a fluorine atom or a C1-C6 perfluoroalkyl group, X 1 represents *—CO—O-L b2 -, *—CO—O-L b4 -CO—O-L b3 -, *—CO—O-L b8 -O—, and *—CO—O-L b10 -O-L b9 -CO—O— where L b2 represents a single bond or a C1-C15 saturated hydrocarbon group, L b3 represents a single bond or a C1-C12 saturated hydrocarbon group, L b4 represents a C1-C13 saturated hydrocarbon group, with the proviso that total carbon number of L b3 and L b4 is 1 to 13, L b8 represents a C1-C14 saturated hydrocarbon group, L b9 represents a C1-C11 saturated hydrocarbon group, L b10 represents a C1-C11 saturated hydrocarbon group, with the proviso that total carbon number of L b9 and L b10 is 1 to 12, and * represents a binding position to —C(R 1 )(R 2 )—, and R 3 represents a hydrogen atom or a methyl group, and Z 1+ represents an organic counter cation.