Electrophotographic photoreceptor, process cartridge, and image forming apparatus

An electrophotographic photoreceptor comprising:

• a conductive substrate;
• and
• a single layer type photosensitive layer disposed on the conductive substrate,
• wherein the single layer type photosensitive layer contains a polyester resin (1) having a dicarboxylic acid unit (A) represented by Formula (A) and a diol unit (B) represented by Formula (B), and a charge transport material, and
• in a case where a value A is a weight-average molecular weight Mw of the polyester resin (1) contained in the single layer type photosensitive layer divided by 10,000 (A=Mw/10,000), a value of a ratio M1/M2 of a mass M1 of the charge transport material contained in the single layer type photosensitive layer to a mass M2 of the single layer type photosensitive layer is defined as Ct, and an average thickness of the single layer type photosensitive layer is defined as Dt (μm),
• expressions of 5≤A≤40,
• 0.40≤Ct≤0.60,
• 27≤Dt≤50, and
• 2.5≤(A×Dt)/(Ct×100)≤48.0 are satisfied,
• in Formula (A), n1 represents 1, 2, or 3, m1's each independently represent 0, 1, 2, 3, or 4, Ra1'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), 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, Rb3, Rb4, Rb5, Rb6, Rb7, Rb8, Rb9, and Rb10 each independently represent a hydrogen atom, 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, an aralkyl group having 7 or more and 20 or less carbon atoms, or an alkoxy group having 1 or more and 6 or less carbon atoms, and Rb1 and Rb2 may be bonded to each other to form a cyclic alkyl group.