Patent ID: 8440713

Claim:
A [1]benzothieno[3,2-b][1]benzothiophene compound represented by formula (I): wherein X and Y are each independently a hydrogen atom, a halogen atom, a functional group which is a straight or branched aliphatic alkenyl group or an alicyclic alkenyl group which is represented by formula (II), a functional group having a carboxyl group which is represented by formula (III), and a functional group having a thiol group which is represented by formula (IV): wherein Ar is selected from the group consisting of optionally substituted benzene, optionally substituted thiophene, optionally substituted naphthalene and optionally substituted thienothiophene, n is an integer of 1 or more, when n is 2 or more, the plurality of Ar groups are the same or each independently different, R 1 and R 2 are each independently a hydrogen atom, a straight or branched aliphatic alkyl group optionally having a halogen atom, or an alicyclic alkyl group optionally having a halogen atom; provided that at least one of X and Y is the functional group of formula (II), the functional group of formula (III) or the functional group of formula (IV).