Patent ID: 6884556

Claim:
An electrophotographic photoreceptor, comprising a photosensitive layer formed on an electroconductive substrate, wherein the photosensitive layer comprises a resin having repeating units of the following formula (1): where, in the formula (1), A represents a plurality of bivalent groups including at least two members selected from the group consisting of bivalent groups of the following formulae (2), (3) and (4) where, in the formulae (2), (3) and (4), each of R 1 to R 24 which are independent of one another, represents a hydrogen atom, a substituted or unsubstituted C 1-10 alkyl group, a substituted or unsubstituted C 1-10 alkoxyl group, a halogen atom, a halogenated alkyl group, or a substituted or unsubstituted C 6-20 aromatic group, and each of X 1 , X 2 and X 3 which may be the same or different, represents a single bond, a bivalent organic group of the formula (5), —O—, —S—, —CO—, —SO 2 — or —(CH 2 ) 8 —, wherein S is an integer of from 2 to 5 where, in the formula (5), each of R 25 to R 29 which are independent of one another, represents a hydrogen atom, a substituted or unsubstituted C 1-10 alkyl group, a substituted or unsubstituted C 1-10 alkoxyl group, a halogen atom, a halogenated alkyl group or a substituted or unsubstituted C 6-20 aromatic group, provided that R 25 and R 26 , and R 27 and R 28 , may be bonded to each other to form a cyclic structure, t is an integer of from 0 to 5, and u is an integer of from 0 to 4.