Patent ID: 6984704

Claim:
A fluoropolymer having monomer units formed by cyclopolymerization of a fluorinated diene represented by the formula (1): CFR 1 ═CR 2 -Q-CR 3 ═CHR 4 (1) wherein each of R 1 , R 2 , R 3 and R 4 which are independent of one another, represents a hydrogen atom, a fluorine atom, an alkyl group having at most 8 carbon atoms, or an alicyclic hydrocarbon group, and at least one of them is an alicyclic hydrocarbon group, provided that part of carbon atoms in the alkyl group or the alicyclic hydrocarbon group may be substituted by a hetero atom or a carbonyl group, and part of hydrogen atoms in the alkyl group or the alicyclic hydrocarbon group may be substituted by a fluorine atom, an alkyl group or a fluoroalkyl group; and Q represents a bivalent organic group having a blocked acidic group capable of developing an acidic group by an acid or a group capable of being converted into such a blocked acidic group.