Patent ID: 8685600

Claim:
An electrophotographic photoreceptor comprising: a conductive substrate; an intermediate layer; a photosensitive layer; and a surface layer, in this order, the surface layer including at least one selected from the group consisting of a guanamine compound and a melamine compound, and two or three charge transporting materials each including a reactive substituent selected from the group consisting of â€”OH, â€”OCH 3 , â€”NH 2 , â€”SH, and â€”COOH, and respectively having mutually different ionization potentials of from 5.31 to 5.77, in an amount of about 90% by weight or more relative to the total solid content of the surface layer, when the number of charge transporting materials contained in the surface layer is 2, the content ratio X of each of the two charge transporting materials satisfying the following Formula (1-2), and when the number of charge transporting materials contained in the surface layer is 3, the content ratio X of each of the three charge transporting materials satisfying the following Formula (1-3): X (1)â‰§ X (2)â€ƒâ€ƒFormula (1-2) X (1)â‰§ X (2)â‰§ X (3)â€ƒâ€ƒFormula (1-3) wherein in Formulae (1-2) and (1-3), X(1) represents a content ratio expressed by % by weight of a charge transporting material that has the highest ionization potential among the two or three charge transporting materials; X(2) represents a content ratio expressed by % by weight of a charge transporting material that has the second highest ionization potential among the two or three charge transporting materials; X(3) represents a content ratio expressed by % by weight of a charge transporting material that has the third highest ionization potential among the three charge transporting materials; in Formula (1-2), X(1) is from 55% by weight to 65% by weight relative to the total solid content of the surface layer; and in Formula (1-3), X(2) is from 38% by weight to 44% by weight relative to the total solid content of the surface layer.