PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS

• US 20140255838A1
• Filed: 05/22/2014
• Published: 09/11/2014
• Est. Priority Date: 01/24/2013
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Matsuda, Hidekazu, Tanaka, Daisuke, Uematsu, Atsushi
• Granted Patent: US 9,411,307 B2
• Time in Patent Office: Days
• US Class Current: 430/56
• CPC Class Codes: G03G 15/0233 Structure, details of the charging member, e.g. chemical composition, surface properties
• CPC Class Codes: G03G 21/1814 Details of parts of process cartridge, e.g. for charging, transfer, cleaning, developing G03G21/1835 takes precedence
• CPC Class Codes: G03G 5/14708 comprising organic material
• CPC Class Codes: G03G 5/14752 Polyesters
• CPC Class Codes: G03G 5/14756 Polycarbonates
• CPC Class Codes: G03G 5/14773 Polycondensates comprising silicon atoms in the main chain

Abstract

A process cartridge that can suppress production of a banding image attributed to contact rotation of an electrophotographic photosensitive member and a charging member and output a high-quality image is provided. The charging member includes an electro-conductive substrate and an electroconductive resin layer, the resin layer contains a binder, a conductive fine particle, and a bowl-shaped resin particle having an opening, and the surface of the charging member has a concavity derived from the opening of the bowl-shaped resin particle and a protrusion derived from the edge of the opening thereof. The electrophotographic photosensitive member includes a support and a photosensitive layer, and the surface layer in the photosensitive member contains a specific resin (α), a specific resin (β), and a specific compound (γ).

Claims

1. A process cartridge comprising:

a charging member; and

an electrophotographic photosensitive member which is electrically charged upon being brought into contact with the charging member, wherein;

the charging member comprises

an electro-conductive substrate and

an electroconductive resin layer formed on the electro-conductive substrate;

the electroconductive resin layer comprises

a binder,

a conductive fine particle, and

a bowl-shaped resin particle which has an opening; and

the surface of the charging member has

a concavity derived from the opening of the bowl-shaped resin particle, and

a protrusion derived from an edge of the opening of the bowl-shaped resin particle;

and wherein;

the electrophotographic photosensitive member comprises

a support and

a photosensitive layer formed on the support, and

a surface layer of the electrophotographic photosensitive member comprises the following resin (α

), resin (β

), and compound (γ

);

resin (α

);

at least one resin selected from the group consisting of polycarbonate resins having no siloxane structure at a terminal and polyester resins having no siloxane structure at a terminal;

resin (β

);

at least one resin selected from the group consisting of polycarbonate resins having a siloxane structure at a terminal, polyester resins having a siloxane structure at a terminal, and acrylic resins having a siloxane structure at a terminal; and

compound (γ

);

at least one compound selected from the group consisting of methyl benzoate, ethyl benzoate, benzyl acetate, ethyl 3-ethoxypropionate, and diethylene glycol ethyl methyl ether.

2. The process cartridge according to claim 1, wherein the resin (α

) is a polycarbonate resin A having a repeating structural unit represented by the following formula (A);

3. The process cartridge according to claim 2, wherein the polycarbonate resin A is a polymer having only one kind of repeating structural unit selected from repeating structural units represented by the following formulas (A-1) to (A-8) or a polymer having a combination of two or more kinds of repeating structural units represented by the following formulas (A-1) to (A-8):

4. The process cartridge according to claim 1, wherein the resin (α

) is a polyester resin B having a repeating structural unit represented by the following formula (B);

5. The process cartridge according to claim 4, wherein the polyester resin B is a polymer having only one kind of repeating structural unit selected from repeating structural units represented by the following formulas (B-1) to (B-9) or a polymer having a combination of two or more kinds of repeating structural units represented by the following formulas (B-1) to (B-9):

6. The process cartridge according to claim 1, wherein the resin (β

) is a polycarbonate resin A′

having a repeating structural unit represented by the following formula (A′

) and a terminal structure represented by the following formula (D);

7. The process cartridge according to claim 1, wherein the resin (β

) is a polyester resin B′

having a repeating structural unit represented by the following formula (B′

) and a terminal structure represented by the following formula (D);

8. The process cartridge according to claim 1, wherein the compound (γ

) is phenol or p-tert-butyl phenol.

9. The process cartridge according to claim 1, wherein the bowl-shaped resin particle is a particle having a resin shell, an opening derived from the partial lack of the shell, and a spherical concavity.

10. The process cartridge according to claim 9, wherein an electroconductive resin layer is formed along an inner wall of the spherical concavity of the bowl-shaped resin particle.

11. An electrophotographic apparatus comprising the process cartridge according to claim 1.