Electrophotographic photosensitive member, process cartridge, and image forming apparatus

An electrophotographic photosensitive member comprising:

• a conductive substrate;
• and
• a photosensitive layer, wherein
• the photosensitive layer is a single layer,
• the photosensitive layer contains a charge generating material, a binder resin, an electron transport material, and a hole transport material,
• the binder resin includes a polyarylate resin,
• the polyarylate resin includes repeating units represented by formula (1), (2), (3), and (4),
• the repeating unit represented by the formula (3) has a percentage content of greater than 0% and less than 50% to a total number of repeats of the repeating units represented by the formulas (1) and (3),
• the repeating unit represented by the formula (4) has a percentage content of at least 35% and less than 70% to a total number of repeats of the repeating units represented by the formulas (2) and (4),
• the electron transport material includes a compound represented by formula (11), (12), (13), (14), (15), (16) or (17),
• the hole transport material includes a compound represented by formula (20), (21), or (22), and
• the electron transport material has a percentage content of at least 15% by mass and no greater than 35% by mass to the mass of the photosensitive layer:
• where in the formula (1),
• R1 and R2 each represent a methyl group and X represents a divalent group represented by formula (X1), or
• R1 and R2 each represent a hydrogen atom and X represents a divalent group represented by formula (X2),
• in the formulas (X1) and (X2), * represents a bond,
• Q1 and Q2 in the formula (11), Q21, Q22, Q23, and Q24 in the formula (12), Q31 and Q32 in the formula (13), Q41, Q42, and Q43 in the formula (14), Q51, Q52, Q53, and Q54 in the formula (15), Q61 and Q62 in the formula (16), and Q71, Q72, Q73, Q74, Q75, and Q76 in the formula (17) each represent, independently of one another, a hydrogen atom, a halogen atom, a cyano group, an alkyl group with a carbon number of at least 1 and no greater than 6, an alkenyl group with a carbon number of at least 2 and no greater than 6, an alkoxy group with a carbon number of at least 1 and no greater than 6, or an aryl group with a carbon number of at least 6 and no greater than 14 optionally substituted with at least one substituent selected from the group consisting of a halogen atom and an alkyl group with a carbon number of at least 1 and no greater than 6, and
• in the formula (17), Y1 and Y2 each represent, independently of one another, an oxygen atom or a sulfur atom,
• in the formula (20), R50 and R51 each represent, independently of one another, a phenyl group, an alkyl group with carbon number of at least 1 and no greater than 6, or an alkoxy group with carbon number of at least 1 and no greater than 6;
• R52, R53, R54, R55, R56, R57, and R58 each represent, independently of one another, a hydrogen atom, an alkyl group with carbon number of at least 1 and no greater than 6, an alkoxy group with carbon number of at least 1 and no greater than 6, or a phenyl group optionally substituted with an alkyl group with carbon number of at least 1 and no greater than 6;
• f1 and f2 each represent, independently of one another, an integer of at least 0 and no greater than 2;
• and f3 and f4 each represent, independently of one another, an integer of at least 0 and no greater than 5,
• in the formula (21), R21, R22, and R23 each represent, independently of one another, an alkyl group with carbon number of at least 1 and no greater than 6;
• R24, R25, and R26 each represent, independently of one another, a hydrogen atom or an alkyl group with carbon number of at least 1 and no greater than 6;
• and b1, b2, and b3 each represent, independently of one another, 0 or 1, and
• in the formula (22), R31, R32, and R33 each represent, independently of one another, an alkyl group with carbon number of at least 1 and no greater than 6, and R34 represents a hydrogen atom or an alkyl group with carbon number of at least 1 and no greater than 6;
• and d1, d2, and d3 each represent, independently of one another, an integer of at least 0 and no greater than 5.