Patent ID: 8206880

Claim:
An electrophotographic photoreceptor, comprising: an electroconductive substrate; and a photosensitive layer, overlying the substrate, wherein the photosensitive layer comprises a complex azo pigment comprising: a first azo compound having the following formula A(H) n (a) wherein A represents a residue of an azo compound, bonded with n pieces of hydrogen atom through one or more heteroatom being N or O and forming a part of the residue A; H represents a hydrogen atom; and n represents an integer of from 1 to 9, and a pigment selected from the group consisting of quinacridone, titanium oxide, fullerene, titanylphthalocyanine, and other azo pigments different from the azo compound having the formula (a), wherein the first azo compound is prepared by dissolving in an organic solvent and de-carbo esterifying a second azo compound having a carbo-ester group and the following formula (I): A(E) n (I) wherein A represents a residue of an azo compound, bonded with n pieces of E group through one or more heteroatom being N or O and forming a part of the residue A; E independently represents a hydrogen atom or a carbo-ester group having a formula of —(═O)—O—R1, wherein R1 represents a substituted or an unsubstituted alkyl group having 4 to 10 carbon atoms, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group or an aralkyl group; and n represents an integer of from 1 to 9.