Patent ID: 7081497

Claim:
A block copolymer comprising at least one segment having an acid group and at least one segment substantially free from an acid group, wherein the segment having an acid group comprises a repeating unit which is a substituted repeating unit represented in the formula (1) with an acid group, —(Ar 1 —X 1 —Ar 2 —X 2 )—, (1) and in the formula (1), X 1 and X 2 being each independently -0-or —S—, Ar 1 and Ar 2 being each independently an aromatic group selected from the groups represented by the following formulae (2) to (4), wherein, R1 is a halogen atom, a hydroxyl group, a nitro group, a nitro group, an amino group, an optionally substituted alkyl group with a carbon number of 1 to 10, an optionally substituted alkoxy group with a carbon number of 1 to 10, an optionally substituted aryl group with a carbon number of 6 to 10, or an optionally substituted aryloxy group with a carbon number of 6 to 10, a is an integer of 0 to 4, and b is an integer of 0 to 6, in a case of plural R 1 , R 1 may be the same or different, or be bonded to each other, Y is a direct bond, -0-, —S—, an optionally substituted alkylene group with a carbon number of 1 to 6, or an optionally substituted alkylenedioxy group with a carbon number of 1 to 6, and n is an integer of 0 to 2, in a case of plural Y, Y may be the same or different, and in a case where both of X 1 and X 2 are -0-, both of Ar 1 and Ar 2 being not the group represented by the formula (2) wherein the segment substantially free from an acid group comprises a repeating unit represented by the following formula (5), —(Ar 3 —Z 1 —Ar 4 —Z 2 )—, (5) in the formula (5), Z 1 and Z 2 independently representing direct bond, —O—or —S—, and Ar 3 and Ar 4 being each independently an aromatic group selected from the groups represented by the following formulae (6) to (10), wherein, R 2 is a halogen atom, a hydroxyl group, a nitrile group, a nitro group, an amino group, an optionally substituted alkyl group with a carbon number of 1 to 10, an optionally substituted alkoxy group with a carbon number of 1 to 10, an optionally substituted aryl group with a carbon number of 6 to 10, or an optionally substituted aryloxy group with a carbon number of 6 to 10, c is an integer of 0 to 4, and d is an integer of 0 to 6, in a case of plural R 2 , R 2 may be the same or different, or be bonded to each other, W is a direct bond, —0—, —S—, —CO—, —SO 2 -, an optionally substituted alkylene group with a carbon number of 1 to 6, or an optionally substituted alkylenedioxy group with a carbon number of 1 to 6, m is an integer of 0 to 2, in a case of plural W, W may be the same or different, A is —O—, —S—, or —NR 3 - in which R 3 is a hydrogen atom or an optionally substituted alkyl group with a carbon number of 1 to 10, two of A may be the same or different, Ar 5 is an aromatic group selected from the groups represented by the following formulae (11) to (14) where, R 2 , W and m are the same as the above, e is an integer of 0 to 2, f is an integer of 0 to 4, and g an integer of 0 to 3.