Electrophotographic photosensitive member, process cartridge, electrophotographic apparatus, and method for producing electrophotographic photosensitive member

A process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge integrally supporting an electrophotographic photosensitive member and at least one device selected from the group consisting of a charging device, a developing device, a transfer device, and a cleaning device,

• wherein the electrophotographic photosensitive member includes an undercoat layer, a charge generation layer, and a charge transport layer in this order,
• the undercoat layer contains
• a cured product of a composition containing an electron transport material,
• a particle having an average primary particle size of 10 nm or more, and
• a silicone oil,
• a content of the particle in the undercoat layer is 3% by mass or more and 20% by mass or less, and
• a content of the silicone oil in the undercoat layer is 0.01% by mass or more and 10% by mass or less relative to the content of the particle.

An electrophotographic apparatus comprising:

• an electrophotographic photosensitive member;
• a charging device;
• an exposure device;
• a developing device;
• and
• a transfer device,
• wherein the electrophotographic photosensitive member includes an undercoat layer, a charge generation layer, and a charge transport layer in this order,
• the undercoat layer contains
• a cured product of a composition containing an electron transport material,
• a particle having an average primary particle size of 10 nm or more, and
• a silicone oil,
• a content of the particle in the undercoat layer is 3% by mass or more and 20% by mass or less, and
• a content of the silicone oil in the undercoat layer is 0.01% by mass or more and 10% by mass or less relative to the content of the particle.

A method for producing an electrophotographic photosensitive member that includes an undercoat layer, a charge generation layer, and a charge transport layer in this order, the method comprising:

• a step of forming an undercoat layer by drying a coating film of a coating liquid for an undercoat layer by heating, the coating liquid containing an electron transport material, a particle having an average primary particle size of 10 nm or more, a silicone oil, a compound represented by formula (A), and a compound represented by formula (B),
• wherein a ratio of the particle to a total solid content in the coating liquid for an undercoat layer is 3% by mass or more and 20% by mass or less,
• a content of the silicone oil in the coating liquid for an undercoat layer is 0.01% by mass or more and 10% by mass or less relative to a content of the particle, and
• a content of the compound represented by formula (A) in the coating liquid for an undercoat layer is 0.3 times or more and 3.0 times or less a content of the compound represented by formula (B) in terms of mass ratio:
• where Ra and Rb each independently represent a substituted or unsubstituted alkyl group having 3 or less carbon atoms, and the substituent of the substituted alkyl group is a methyl group, and
• where Rc and Rd each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group having 4 or less carbon atoms, and the substituent of the substituted alkyl group is a methyl group.