ELECTROPHOTOGRAPHIC MEMBER, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS

• US 20190018362A1
• Filed: 07/09/2018
• Published: 01/17/2019
• Est. Priority Date: 07/12/2017
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Morishita, Hiroshi, Sakurai, Yuji, Ishida, Kazutoshi, Nakamura, Minoru, Ishii, Toru, Sugiyama, Ryo, Matsunaga, Kenta
• Granted Patent: US 10,310,447 B2
• Time in Patent Office: Days
• CPC Class Codes: G03G 15/0233 Structure, details of the charging member, e.g. chemical composition, surface properties
• CPC Class Codes: G03G 15/0808 characterised by the developer supplying means, e.g. structure of developer supply roller
• CPC Class Codes: G03G 15/0818 characterised by the structure of the donor member, e.g. 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 5/04 Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor

Abstract

Provided is an electrophotographic member which can suppress adhesion of the toner component and fogging even in the case of printing a large number of sheets. The electrophotographic member includes an electroconductive support and an elastic layer and has convex portions composed of the elastic layer on a surface of the electrophotographic member and a filled portion containing a resin at a valley portion between the convex portions, the filled portion has a height lower than heights of the convex portions, and the surface of the electrophotographic member has a specific Martens hardness.

Claims

1. An electrophotographic member comprising an electroconductive support and an elastic layer on the support, wherein

the electrophotographic member has convex portions composed of the elastic layer on a surface of the electrophotographic member,

the electrophotographic member has a filled portion containing a resin at a valley portion between the convex portions,

the filled portion has a height lower than heights of the convex portions,

the surface of the electrophotographic member includes

a first region which is a surface of the elastic layer uncovered with the filled portion and

a second region which is a surface of the filled portion, and wherein when

a Martens hardness measured at a surface of the first region is defined as H1, and a Martens hardness measured at a surface of the second region is defined as H2, H1 and H2 satisfy a following relationship:

H2>

H1.

2. The electrophotographic member according to claim 1, wherein the electrophotographic member has a roller shape.

3. The electrophotographic member according to claim 1, wherein a difference between H1 and H2 is 0.5 N/mm² or more and 35.0 N/mm² or less.

4. The electrophotographic member according to claim 1, wherein a coverage factor of a part covered with the second region on the surface of the electrophotographic member is 20% or more and 80% or less.

5. The electrophotographic member according to claim 1, wherein L2/L1 is 0.2 or more and 0.8 or less where L1 denotes an average value of the heights of the convex portions and L2 denotes an average value of the heights of the filled portions.

6. An electrophotographic process cartridge which is configured to be detachably attachable to a main body of an electrophotographic image forming apparatus and equipped with a developing apparatus including an electrophotographic member, wherein

the electrophotographic member includes an electroconductive support and an elastic layer on the support,

the electrophotographic member has convex portions composed of the elastic layer on a surface of the electrophotographic member,

the electrophotographic member has a filled portion containing a resin at a valley portion between the convex portions,

the filled portion has a height lower than heights of the convex portions,

the surface of the electrophotographic member includes

a first region which is a surface of the elastic layer uncovered with the filled portion and

a second region which is a surface of the filled portion, and wherein when

a Martens hardness measured at a surface of the first region is defined as H1, and a Martens hardness measured at a surface of the second region is defined as H2, H1 and H2 satisfy a following relationship:

H2>

H1.

7. The electrophotographic process cartridge according to claim 6, comprising the electrophotographic member as a developing member.

8. The electrophotographic process cartridge according to claim 7, further comprising at least one member selected from the group consisting of a toner feed roller, a toner regulating member, and an electrophotographic photosensitive member, wherein the member is in contact with a surface of the developing member.

9. An electrophotographic image forming apparatus comprising:

an image carrier for carrying an electrostatic latent image;

a charging apparatus for primarily charging the image carrier;

an exposure apparatus for forming an electrostatic latent image on the image carrier primarily charged;

a developing apparatus for developing the electrostatic latent image with a toner to form a toner image; and

a transfer apparatus for transferring the toner image onto a transfer material, wherein

the developing apparatus includes an electrophotographic member,

the electrophotographic member has convex portions composed of an elastic layer on a surface of the electrophotographic member,

the electrophotographic member has a filled portion containing a resin at a valley portion between the convex portions,

the filled portion has a height lower than heights of the convex portions,

the surface of the electrophotographic member includes

a first region which is a surface of the elastic layer uncovered with the filled portion and

a second region which is a surface of the filled portion, and wherein when

a Martens hardness measured at a surface of the first region is defined as H1, and a Martens hardness measured at a surface of the second region is defined as H2, H1 and H2 satisfy a following relationship;

H2>

H1.

10. The electrophotographic image forming apparatus according to claim 9, further comprising at least one member selected from the group consisting of a toner feed roller, a toner regulating member, and an electrophotographic photosensitive member, wherein the member is in contact with a surface of the developing member.