Patent ID: 7442479
Filing Date: 2008-10-28
Classification: G03G

Abstract:
1. A photoreceptor comprising at least an electroconductive substrate, and a charge blocking layer, a moiré preventing layer, and a photosensitive layer, which are located overlying the electroconductive substrate in this order, wherein the photosensitive layer comprises an azo pigment having the following formula (I): wherein R 201 and R 202 independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxyl group, or a cyano group; and Cp 1 and Cp 2 independently represent a residual group of a coupler, which has the following formula (II): wherein R 203 represents a hydrogen atom, an alkyl group, or an aryl group; R 204 , R 205 , R 206 , R 207 and R 208 independently represent a hydrogen atom, a nitro group, a cyano group, a halogen atom, an alkyl group, an alkoxyl group, a dialkylamino group or a hydroxyl group; and Z represents an atomic group needed for constituting a substituted or unsubstituted aromatic carbon ring or a substituted or unsubstituted aromatic heterocyclic ring, and wherein the photosensitive layer is prepared by coating a coating liquid including a dispersion which is prepared by dispersing the azo pigment in a solvent to an extent such that an average particle diameter of the azo pigment is not greater than 0.3 μm and a standard deviation of the particle diameter is not greater than 0.2 μm, followed by filtering with a filter having an effective pore diameter not greater than 5 μm and which includes only particles of the azo pigment having particle diameters not greater than 0.25 μm.