Abstract: An electrophotographic photoreceptor is disclosed, comprising an electrically conductive substrate having thereon and a light-sensitive layer, said light-sensitive layer comprising an electric charge generating layer and an electric charge transporting layer, wherein the electric charge generating layer contains an electric charge generating organic pigment having positive hole transporting properties and a pyrylium compound represented by the formula (I) or (II): ##STR1## wherein X is an oxygen atom or a sulfur atom; R.sub.1 to R.sub.5 are each a hydrogen atom, and alkyl group, a cycloalkyl group, an alkoxycarbonyl group, a benzyl group, a substituted or unsubstituted styryl group, or a substituted or unsubstituted phenyl group, and Z.sup..crclbar. is an anion.

Abstract: A bisazo compound having good electrophotographic properties is disclosed, which is represented by formula (I) ##STR1## wherein X represents a hydrogen atom, a chlorine atom or a nitro group. A process for producing the bisazo compound is also disclosed.

Abstract: An electrophotographic photoreceptor is disclosed, comprising a conductive support having provided thereon a photosensitive layer containing a bisazo compound respresented by formula (I) ##STR1## wherein Y represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group or a hydroxyl group; and A represents a substituted or unsubstituted divalent aromatic hydrocarbon group or a substituted unsubstituted divalent nitrogen-containing heterocyclic group. The photoreceptor exhibits excellent sensitivity and durability.

Abstract: An electrophotographic photoreceptor is disclosed, comprising a conductive support having provided thereon a photosensitive layer containing a bisazo compound represented by formula (I) ##STR1## wherein X represents a halogen atom or a nitro group, and A represents a substituted or unsubstituted divalent aromatic hydrocarbon group or a substituted unsubstituted divalent nitrogen-containing heterocyclic group. The photoreceptor exhibits excellent sensitivity and durability.