Patent ID: 7431996

Claim:
A copolymerized polyester resin comprising: at least one repeating unit represented by the following formula (1); and at least one repeating unit represented by the following formula (2); wherein Ar 1 , Ar 2 and Ar 3 independently represent a substituted or unsubstituted arylene group, a substituted or unsubstituted bivalent heterocyclic group, or a combination thereof; T 1 and T 2 represent a linear or branched bivalent hydrocarbon group having 1 to 10 carbon atoms; and n represents 0 or 1, wherein Ar 4 , Ar 6 and Ar 8 independently represent a substituted or unsubstituted arylene group, a substituted or unsubstituted bivalent heterocyclic group, or a combination thereof; Ar 5 and Ar 7 independently represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group; R 1 and R 2 independently represent a hydrogen atom, a cyano group, an alkyl group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, or a heterocyclic group; and T 3 and T 4 represent a linear or branched bivalent hydrocarbon group having 1 to 10 carbon atoms.