Patent ID: 8822588

Claim:
A fluorine-containing polymer comprising a repeating unit of the general formula (2) and produced by homopolymerization or copolymerization with another polymerizable double bond-containing monomer where W represents a divalent linking group of the general formula (3) n represents an integer of 1 to 3; R′ represents a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a hexafluoroisopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a norbornyl group or a adamantyl group; A is represented by B 1 -B 2 -B 3 ; B 1 represents a single bond or a group selected from the following groups; B 2 represents a single bond; a linear, branched or cyclic alkylene group; or a group in which a linear or branched alkylene group and a cyclic alkylene group are bonded in series, wherein the linear, branched or cyclic alkylene group or the group in which the linear or branched alkylene group and the cyclic alkylene group are bonded in series may have a carbonyloxy group or an amide bond inserted therein and all or some of the hydrogen atoms of the linear, branched or cyclic alkylene group may be substituted with fluorine; B 3 represents a single bond or a group selected from the following groups: R 1 each independently represents a perfluoroalkyl group; Q represents a unit structure formed by cleavage of a double bond of a polymerizable double bond-containing group; and M + represents a hydrogen cation, a metal ion or a quaternary ammonium ion of the general formula (15) where R 11 to R 14 each independently represent a substituted or unsubstituted C 1 -C 20 alkyl or aryl group.