Process cartridge and image forming apparatus

Patent metadata

Field	Value
Publication number	US-11144007-B2
Application number	US-201916681100-A
Country	US
Kind code	B2
Filing date	Nov 12, 2019
Priority date	Nov 14, 2018
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

A process cartridge using an image forming apparatus, including a rotatable image bearing member having a circumferential surface; a developing unit configured to supply a developing agent to the image bearing member; and a cleaning member that cleans the circumferential surface, wherein the developing agent contains a toner including toner particles and a metal soap, the image bearing member includes a plurality of grooves formed on the circumferential surface to extend in a circumferential direction of the circumferential surface and to be arranged side by side in a rotation axis direction, and the plurality of grooves and portions between the grooves form concave-convex portions on the circumferential surface. The circumferential surface of the image bearing member had surface roughness Rz of 0<Rz≤0.70 μm and average interval Sm between concave-convex portions on the circumferential surface of 0<Sm≤70.0 μm.

First claim

What is claimed is:

1. A process cartridge for use in an image forming apparatus, comprising:
an image bearing member configured to be rotatable and have a circumferential surface on which a latent image is formed;
a developing unit storing a developing agent, the developing unit being configured to supply the developing agent to the image bearing member in order to develop the latent image on the image bearing member; and
a cleaning member configured to contact the circumferential surface of the image bearing member and clean the circumferential surface,
wherein
the developing agent stored in the developing unit contains a toner including toner particles and a metal soap,
the image bearing member includes a plurality of grooves formed on the circumferential surface so as to extend in a circumferential direction of the circumferential surface and to be arranged side by side in a rotation axis direction, the plurality of grooves and portions between the grooves forming concave-convex portions on the circumferential surface,
the circumferential surface of the image bearing member has a ten-point average surface roughness Rz that is less than an average particle diameter of the metal soap so that the metal soap remains on the circumferential surface of the image bearing member,
the average particle diameter of the metal soap is at least 0.15 μm and not more than 2.00 μm so that the metal soap is supplied from the toner to the grooves on the surface of the image bearing member, and
the ten-point average surface roughness Rz is in a range of 0.10≤Rz≤0.53 μm and an average interval Sm between concave-convex portions on the circumferential surface of 0<Sm≤70.0 μm so as to increase an amount of time that the metal soap remains on the circumferential surface, thereby reducing an occurrence of image smearing.

2. The process cartridge according to claim 1 , wherein
the toner includes inorganic silicon fine particles present on the surface of the toner particles.

3. The process cartridge according to claim 1 , wherein
the toner particles include fine particles present on the surface of the toner particles, the fine particles containing an organosilicon polymer having a structure represented by the following Formula (1):
R—SiO 3/2   (1)

wherein R represents a hydrocarbon group having at least 1 and not more than 6 carbon atoms.

4. The process cartridge according to claim 3 , wherein
when the ratio of the amount of silicon in the toner particles after washing with aqueous solution of neutral detergent to the amount of silicon in the toner particles before washing with the aqueous solution of neutral detergent is defined as an adhesion ratio, the adhesion ratio of the fine particles to the surface of the toner particles is at least 30% and not more than 90%.

5. The process cartridge according to claim 3 , wherein
the toner includes no inorganic silicon fine particles as an external additive.

6. The process cartridge according to claim 1 , wherein
the toner particles include an organosilicon polymer covering the surface of the toner particles, the organosilicon polymer having a structure represented by the following Formula (1):
R—SiO 3/2   (1)

wherein R represents a hydrocarbon group having at least 1 and not more than 6 carbon atoms.

7. The process cartridge according to claim 6 , wherein
R represents an aliphatic hydrocarbon group having at least 1 and not more than 3 carbon atoms.

8. The process cartridge according to claim 6 , wherein
when the ratio of the amount of silicon in the toner particles after washing with aqueous solution of neutral detergent to the amount of silicon in the toner particles before washing with the aqueous solution of neutral detergent is defined as an adhesion ratio, the adhesion ratio of the organosilicon polymer on the surface of each of the toner particles is 90% or more.

9. The process cartridge according to claim 1 , wherein
the metal soap contains at least one metal selected from the group consisting of zinc, calcium, and magnesium.

10. The process cartridge according to claim 1 , wherein
the metal soap is zinc stearate, calcium stearate, or magnesium stearate.

11. The process cartridge according to claim 1 , wherein
the developing unit is a contact developing unit that performs developing by contacting a developing agent carrying member carrying the developing agent with the image bearing member.

12. The process cartridge according to claim 1 , wherein
the image bearing member includes a protective layer on the outermost layer.

13. The process cartridge according to claim 12 , wherein
the protective layer contains an acrylic resin.

14. The process cartridge according to claim 1 , further comprising
a frame body which rotatably supports the image bearing member and to which the cleaning member is fixed,
wherein
the cleaning member includes a plate-like elastic body and a plate-like support that supports the plate-like elastic body,
the plate-like elastic body has one end that is fixed to the plate-like support and the other end as a free end that comes into contact with the circumferential surface,
the plate-like support has one end that is fixed to the frame body and the other end as a free end to which the plate-like elastic body is fixed, and
a direction that extends from the one end of the plate-like support to the other end of the plate-like elastic body is opposite to a rotation direction of the image bearing member at a portion where the other end is in contact with the circumferential surface.

15. The process cartridge according to claim 1 , wherein
in an orientation during use, the image bearing member rotates so that the circumferential surface moves in a downward direction at a portion where the cleaning member is in contact.

16. An image forming apparatus, comprising:
a device body; and
the process cartridge according to claim 1 which is detachable from the device body.

17. A process cartridge for use in an image forming apparatus, comprising:
an image bearing member configured to be rotatable and have a circumferential surface on which a latent image is formed;
a developing unit storing a developing agent, the developing unit configured to supply the developing agent to the image bearing member in order to develop the latent image on the image bearing member; and
a cleaning member configured to contact the circumferential surface of the image bearing member and clean the circumferential surface,
wherein
the developing agent stored in the developing unit contains a toner including toner particles and a metal soap,
the image bearing member includes a plurality of grooves formed on the circumferential surface so as to extend in a circumferential direction of the circumferential surface and to be arranged side by side in a rotation axis direction, the plurality of grooves and portions between the grooves forming concave-convex portions on the circumferential surface, and
the circumferential surface of the image bearing member has a ten-point average surface roughness Rz of 0<Rz≤0.70 μm and an average interval Sm between concave-convex portions on the circumferential surface of 0<Sm≤70.0 μm, and
an average particle diameter of the metal soap is larger than the ten-point average surface roughness Rz,
wherein the toner particles include an organosilicon polymer covering the surface of the toner particles,
wherein when the ratio of the amount of silicon in the toner particles after washing with aqueous solution of neutral detergent to the amount of silicon in the toner p

Assignees

• Canon Kk

Inventors

• Hagiwara Shinichi
• Ikami Yasukazu
• Ikada Kosuke
• Nakata Keitaro
• Shimozawa Hideharu

Classifications

• G03G15/75 Primary

  Details relating to xerographic drum, band or plate, e.g. replacing, testing (electrographic recording members per se G03G5/00) · CPC title

• G03G15/751

  relating to drum (G03G15/757 takes precedence) · CPC title

• G03G5/005

  Materials for treating the recording members, e.g. for cleaning, reactivating, polishing · CPC title

• G03G15/754

  relating to band, e.g. tensioning (G03G15/757 takes precedence) · CPC title

• G03G9/09725

  Silicon-oxides; Silicates · CPC title