Patent ID: 7232641

Claim:
A polymer which has at least one or more of a repeating unit represented by a following general formula (1a), a repeating unit represented by a following general formula (2a) and a repeating unit represented by a following general formula (3b), and a repeating unit represented by a following general formula (1c), wherein R 1 represents any one of a hydrogen atom, a methyl group and —CH 2 CO 2 R 6 , R 2 represents any one of a hydrogen atom, a methyl group and —CO 2 R 6 , R 1 and R 2 in the repeating units (1a) and (2a) may be the same or different, R 3 to R 5 each independently represent a monovalent hydrocarbon group having 1–15 carbon atoms which may contain a hetero atom, R 6 represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1–15 carbon atoms, R 15 represents any one of a hydrogen atom, a methyl group and —CH 2 CO 2 R 6 , R 14 represents any one of a hydrogen atom, a methyl group and —CO 2 R 6 , R 16 represents a single bond or a linear or branched alkylene group having 1–4 carbon atoms, R 17 represents a fluorine atom or a trifluoro methyl group, R 18 represents any one of a hydrogen atom, an acyl group having 1–10 carbon atoms and an acid labile group, R 21 and R 22 each independently represent a hydrogen atom or a fluorine atom, R 23 and R 24 each independently represent a hydrogen atom or a linear or branched alkyl group having 1–6 carbon atoms, R 25 is a linear, branched or cyclic alkyl group having 1–20 carbon atoms, Y 2 is —O— or —C(═O)—O—, Z 1 is a bridged cyclic hydrocarbon group having 4–10 carbon atoms, which may have —O— and/or —S—, and a1, a2, c, and b3 fall within the range that 0≦a1≦0.8, 0≦a2≦0.8, 0≦b3≦0.8, 0.1≦a1+a2+b3≦0.8, and 0<c≦0.9.