Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

A process cartridge integrally supporting:

• an electrophotographic photosensitive member;
• and at least one unit selected from the group consisting of a charging unit, a developing unit, a transfer unit and a cleaning unit, the process cartridge being detachably attachable to an electrophotographic apparatus main body, wherein
• the electrophotographic photosensitive member comprises:
• a support;
• an undercoat layer;
• and a photosensitive layer in the mentioned order,
• the undercoat layer comprises a binder resin and a strontium titanate particle,
• the strontium titanate particle has a maximum peak at a position of 2θ=32.20±0.20 (θ represents a Bragg angle) in a CuKα characteristic X-ray diffraction pattern, and
• a half-value width of the maximum peak is 0.10 deg or more and 0.50 deg or less.

An electrophotographic apparatus comprising:

• a photoelectric photosensitive member;
• a charging unit;
• an exposing unit;
• a developing unit;
• and a transfer unit, wherein
• the electrophotographic photosensitive member comprises:
• a support;
• an undercoat layer;
• and
• a photosensitive layer in the mentioned order,
• the undercoat layer comprises a binder resin and a strontium titanate particle,
• the strontium titanate particle has a maximum peak at a position of 2θ=32.20±0.20 (θ represents a Bragg angle) in a CuKα characteristic X-ray diffraction pattern, and
• a half-value width of the maximum peak is 0.10 deg or more and 0.50 deg or less.