Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus
AssigneeCanon Kabushiki Kaisha
InventorsKunihiko Sekido, Masashi Nishi
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Abstract
An electrophotographic photosensitive member capable of maintaining a charging ability during repeated use is provided. An electrophotographic photosensitive member having a support, a conductive layer, a photosensitive layer and a protective layer in this order, wherein the protective layer contains a binding resin and a metal oxide particle, the metal oxide particle has a core and a coating layer, the core and the coating layer each contain titanium oxide, and the coating layer further includes niobium.
Claims13
An electrophotographic photosensitive member, comprising:
- a support, a conductive layer, a photosensitive layer and a protective layer in this order;
- the protective layer comprising a binding resin and a metal oxide particle;
- the metal oxide particle comprising a core bearing a coating layer;
- the core comprising titanium oxide and niobium;
- and
- the coating layer comprising titanium oxide, wherein
- the content of the metal oxide particle is at least 33% by volume based on a total volume of the protective layer,
- the content of niobium in the metal oxide particles is 5.0 to 5.2% by mass based on the total mass of the coating layer, and
- A≤1.0 and 20×B<C when A (%) is an oxygen deficiency rate of the metal oxide particle, B (%) is an oxygen deficiency rate of the core and C (%) is an oxygen deficiency rate of the coating layer.
A process cartridge integrally supporting at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit, and being removably mounted onto the main body of an electrophotographic apparatus, the process cartridge comprising:
- an electrophotographic photosensitive member, the electrophotographic photosensitive member comprising a support, a conductive layer, a photosensitive layer and a protective layer in this order;
- the protective layer comprising a binding resin and a metal oxide particle;
- the metal oxide particle comprising a core and a coating layer;
- the core comprising titanium oxide and niobium;
- and
- the coating layer comprising titanium oxide, wherein
- the content of the metal oxide particle is at least 33% by volume based on a total volume of the protective layer,
- the content of niobium in the metal oxide particles is 5.0 to 5.2% by mass based on the total mass of the coating layer, and
- A≤1.0 and 20×B<C when A (%) is an oxygen deficiency rate of the metal oxide particle, B (%) is an oxygen deficiency rate of the core and C (%) is an oxygen deficiency rate of the coating layer.
An electrophotographic apparatus, comprising:
- an electrophotographic photosensitive member, a charging unit, an exposing unit, a developing unit and a transferring unit;
- the electrophotographic photosensitive member comprising a support, a conductive layer, a photosensitive layer and a protective layer in this order;
- the protective layer comprising a binding resin and a metal oxide particle;
- the metal oxide particle comprising a core and a coating layer;
- the core comprising titanium oxide and niobium;
- and
- the coating layer comprising titanium oxide, wherein
- the content of the metal oxide particle is at least 33% by volume based on a total volume of the protective layer,
- the content of niobium in the metal oxide particles is 5.0 to 5.2% by mass based on the total mass of the coating layer, and
- A≤1.0 and 20×B<C when A (%) is an oxygen deficiency rate of the metal oxide particle, B (%) is an oxygen deficiency rate of the core and C (%) is an oxygen deficiency rate of the coating layer.
Dependencies are inferred from the claim text.