Patent ID: 8895675

Claim:
A block copolymer consisting essentially of two or more of blocks of the following formula (1): wherein in the formula (1), Ar represents a conjugative divalent group and represents the same divalent group in an identical block, and m represents a number of 1 or more showing the number average polymerization degree of Ar present in one block, at least two of a plurality of m's present in the copolymer represent a number of 5 or more, Ar's in adjacent two blocks in the copolymer are mutually different, and the copolymer has two Ar's when composed of 2 blocks of the formula (1), has two or more Ar's when composed of 3 blocks of the formula (1) and has four or more Ar's when composed of 4 or more blocks of the formula (1), and wherein Ar's in different blocks all represent different divalent groups.