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 photosensitive layer,
• the photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin,
• the hole transport material includes a triphenylamine derivative,
• the triphenylamine derivative is represented by a general formula (HT) shown below,
• the electron transport material includes a compound represented by a general formula (ET1), a general formula (ET2), a general formula (ET3), a general formula (ET4), or a general formula (ET5) shown below,
• the binder resin includes only a polyarylate resin, and
• the polyarylate resin is represented by a general formula (1) shown below,
• in the general formula (1),
• r and s represent an integer of at least 0 and no greater than 49,
• t and u represent an integer of at least 1 and no greater than 50,
• r+s+t+u=100,
• r+t=s+u,
• r and t may be the same as or different from each other,
• s and u may be the same as or different from each other,
• kr represents 3,
• kt represents 3,
• X and Y each represent, independently of one another, a divalent group represented by a chemical formula (2A), a chemical formula (2C), a chemical formula (2D), a chemical formula (2E), a chemical formula (2F), or a chemical formula (2G) shown below, and
• X and Y differ from each other,
• in the general formula (HT),
• R1, R2, and R3 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 4 or an alkoxy group having a carbon number of at least 1 and no greater than 4,
• k, p, and q each represent, independently of one another, an integer of at least 0 and no greater than 5,
• m1 and m2 each represent, independently of one another, an integer of at least 1 and no greater than 3,
• when k represents an integer of at least 2, plural chemical groups represented by R1 may be the same as or different from one another,
• when p represents an integer of at least 2, plural chemical groups represented by R2 may be the same as or different from one another, and
• when q represents an integer of at least 2, plural chemical groups represented by R3 may be the same as or different from one another,
• in the general formula (ET1),
• R11 and R12 represent an alkyl group having a carbon number of at least 1 and no greater than 6,
• in the general formula (ET2),
• R13, R14, R15, and R16 represent an alkyl group having a carbon number of at least 1 and no greater than 6,
• in the general formula (ET3),
• R17 and R18 each represent, independently of one another, an aryl group having a carbon number of at least 6 and no greater than 14 and optionally having one or more alkyl groups having a carbon number of at least 1 and no greater than 3,
• in the general formula (ET4),
• R19 and R20 represent an alkyl group having a carbon number of at least 1 and no greater than 6, and
• R21 represents an aryl group having a carbon number of at least 6 and no greater than 14 and optionally having one or more halogen atoms, and
• in the general formula (ET5),
• R22, R23, R24, and R25 represent an alkyl group having a carbon number of at least 1 and no greater than 6.