Electrophotographic photoreceptor, process cartridge, and image forming apparatus

Abstract

An electrophotographic photoreceptor includes a conductive substrate, an undercoat layer disposed on the conductive substrate, and a photosensitive layer disposed on the undercoat layer, in which the undercoat layer contains a binder resin and at least one perinone compound selected from the group consisting of a compound represented by Formula (1) and a compound represented by Formula (2), the photosensitive layer contains a polyester resin (1) having at least one dicarboxylic acid unit (A) selected from the group consisting of a dicarboxylic acid unit (A2) represented by Formula (A2), a dicarboxylic acid unit (A3) represented by Formula (A3), and a dicarboxylic acid unit (A4) represented by Formula (A4), and a diol unit (B) represented by Formula (B), and a mass proportion of the polyester resin (1) in the photosensitive layer is 15% by mass or greater, in Formula (1), R11, R12, R13, R14, R15, R16, R17, and R18 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, an aralkyl group, an aryl group, an aryloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkoxycarbonylalkyl group, an aryloxycarbonylalkyl group, or a halogen atom, R11 and R12, R12 and R13, and R13 and R14 may be each independently linked to each other to form a ring, and R15 and R16, R16 and R17, and R17 and R18 may be each independently linked to each other to form a ring, in Formula (2), R21, R22, R23, R24, R25, R26, R27, and R28 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, an aralkyl group, an aryl group, an aryloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkoxycarbonylalkyl group, an aryloxycarbonylalkyl group, or a halogen atom, R21 and R22, R22 and R23, and R23 and R24 may be each independently linked to each other to form a ring, and R25 and R26, R26 and R27, and R27 and R28 may be each independently linked to each other to form a ring, in Formula (A2), n201 and n202 each independently represent an integer of 0 or greater and 4 or less, and n201 pieces of Ra201's and n202 pieces of Ra202's each independently represent an alkyl group having 1 or more and 10 or less carbon atoms, an aryl group having 6 or more and 12 or less carbon atoms, or an alkoxy group having 1 or more and 6 or less carbon atoms, in Formula (A3), n301 and n302 each independently represent an integer of 0 or greater and 4 or less, and n301 pieces of Ra301's and n302 pieces of Ra302's each independently represent an alkyl group having 1 or more and 10 or less carbon atoms, an aryl group having 6 or more and 12 or less carbon atoms, or an alkoxy group having 1 or more and 6 or less carbon atoms, in Formula (A4), n401 represents an integer of 0 or greater and 6 or less, and n401 pieces of Ra401's each independently represent an alkyl group having 1 or more and 10 or less carbon atoms, an aryl group having 6 or more and 12 or less carbon atoms, or an alkoxy group having 1 or more and 6 or less carbon atoms, in Formula (B), ArB1 and ArB2 each independently represent an aromatic ring that may have a substituent, LB represents a single bond, an oxygen atom, a sulfur atom, or —C(Rb1)(Rb2)—, and nB1 represents 0, 1, or 2. Rb1 and Rb2 each independently represent a hydrogen atom, an alkyl group having 1 or more and 20 or less carbon atoms, an aryl group having 6 or more and 12 or less carbon atoms, or an aralkyl group having 7 or more and 20 or less carbon atoms, and Rb1 and Rb2 may be bonded to each other to form a cyclic alkyl group.

Dependencies are inferred from the claim text.