Abstract: A fluoropolymer having functional groups and having high transparency in a wide wavelength range is provided, and a resist composition and a composition for a resist protective film, comprising the fluoropolymer, wherein the fluoropolymer has monomer units formed by cyclopolymerization of a fluorinated diene represented by the formula (1): CF2?CFCF2C(CF3)(OR1)—(CH2)nCR2?CHR3??(1) wherein R1 is a hydrogen atom, an alkyl group having at most 20 carbon atoms, or (CH2)aCOOR4 (wherein a is 0 or 1, and R4 is a hydrogen atom or an alkyl group having at most 20 carbon atoms), each of R2 and R3, which are independent of each other, is a hydrogen atom or an alkyl group having at most 12 carbon atoms, and n is 0 or 2, provided that when n is 0, at least one of R1, R2 and R3 is other than a hydrogen atom.

Abstract: To provide a fluoropolymer having functional groups and having high transparency in a wide wavelength range, and a resist composition and a composition for a resist protective film, comprising the fluoropolymer. A fluoropolymer having monomer units formed by cyclopolymerization of a fluorinated diene represented by the formula (1): CF2?CFCF2C(CF3)(OR1)—(CH2)nCR2?CHR3??(1) wherein R1 is a hydrogen atom, an alkyl group having at most 20 carbon atoms, or (CH2)aCOOR4 (wherein a is 0 or 1, and R4 is a hydrogen atom or an alkyl group having at most 20 carbon atoms), each of R2 and R3, which are independent of each other, is a hydrogen atom or an alkyl group having at most 12 carbon atoms, and n is 0 or 2, provided that when n is 0, at least one of R1, R2 and R3 is other than a hydrogen atom.

Abstract: A fluorocopolymer having units derived from a monomer unit formed by cyclopolymerization of a fluorinated diene and units derived from a monomer unit formed by cyclopolymerization of a functional group-containing fluorinated diene having a specific structure or a monomer unit formed by polymerization of an acrylic monomer having a specific structure, a method for its production, and a resist composition.

Abstract: A fluoropolymer (A) having units derived from monomer units formed by cyclopolymerization of at least one fluorinated diene selected from a fluorinated diene represented by the formula (1) and a fluorinated diene represented by the formula (2), and units derived from monomer units formed by cyclopolymerization of a fluorinated diene represented by the formula (3): CF2?CFCF2—C(CF3)(OR1)—CH2CH?CH2??(1) CF2?CFCH2—CH((CH2)nC(CF3)2(OR1))—CH2CH?CH2??(2) CF2?CFCH2—CH(COOR2)—CH2CH?CH2??(3) wherein R1 represents a hydrogen atom, a blocked group of a hydroxyl group capable of being converted into a hydrogen atom by an acid, or a blocked carboxyl group-containing organic group capable of being converted into a carboxyl group-containing organic group by an acid, R2 represents a hydrocarbon group having at most 20 carbon atoms, and n represents 0 or 1.

Abstract: To provide a fluoropolymer having functional groups and having high transparency in a wide wavelength region, and a resist composition comprising the fluoropolymer. A fluorinated copolymer having units derived from a monomer unit formed by cyclopolymerization of a fluorinated diene represented by the following formula (1): CF2?CFCH2CH(CH2C(CF3)2(OR1))CH2CH?CH2 ??(1) wherein R1 is a hydrogen atom, an alkyl group having at most 20 carbon atoms, which may have an etheric oxygen atom, an alkoxycarbonyl group having at most 6 carbon atoms, or CH2R2 (wherein R2 is an alkoxycarbonyl group having at most 6 carbon atoms), and units derived from a monomer unit formed by cyclopolymerization of another monomer or units derived from a monomer unit formed by polymerization of an acrylic monomer, and a resist composition having such a fluorinated copolymer as a base polymer.

Abstract: A fluoropolymer (A) having units derived from monomer units formed by cyclopolymerization of at least one fluorinated diene selected from a fluorinated diene represented by the formula (1) and a fluorinated diene represented by the formula (2), and units derived from monomer units formed by cyclopolymerization of a fluorinated diene represented by the formula (3): CF2?CFCF2—C(CF3)(OR1)—CH2CH?CH2??(1) CF2?CFCH2—CH((CH2)nC(CF3)2(OR1))—CH2CH?CH2??(2) CF2?CFCH2—CH(COOR2)—CH2CH?CH2??(3) wherein R1 represents a hydrogen atom, a blocked group of a hydroxyl group capable of being converted into a hydrogen atom by an acid, or a blocked carboxyl group-containing organic group capable of being converted into a carboxyl group-containing organic group by an acid, R2 represents a hydrocarbon group having at most 20 carbon atoms, and n represents 0 or 1.