Developer carrying member, developing assembly, process cartridge, and image forming apparatus

• US 9,261,814 B2
• Filed: 11/04/2014
• Issued: 02/16/2016
• Est. Priority Date: 11/13/2013
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Hagiwara, Kazunari, Orihara, Tatsuaki, Tokiwa, Shuhei, Matsumoto, Yasuyuki, Haraguchi, Manami, Nakamoto, Atsushi, Horiguchi, Yasuhiro
• Primary Examiner(s): Laballe, Clayton E
• Assistant Examiner(s): Smith, Linda B
• Application Number:
  US14/532,487
• Publication Number:
  US 20150132032A1
• Time in Patent Office: 469 Days
• Field of Search: 399/286
• US Class Current: 1/1
• CPC Class Codes: G03G 15/0818 characterised by the structure of the donor member, e.g. surface properties

Abstract

A developing roller that is capable of carrying toner on a surface thereof, and that supplies the toner carried on the surface to a surface of a photosensitive drum when a voltage is applied thereto, includes: an elastic layer; and a surface layer that covers the elastic layer and contains aluminum oxide, wherein the aluminum oxide of the surface layer contains tetracoordinated aluminum atoms and hexacoordinated aluminum atoms existing in a higher proportion than the tetracoordinated aluminum atoms.

Claims

1. A developer carrying member that is capable of carrying a developer on a surface thereof, and that supplies the developer carried on the surface to a surface of an image bearing member when a voltage is applied thereto, comprising:

an elastic layer; and

a surface layer that covers the elastic layer and contains aluminum oxide,

wherein the aluminum oxide of the surface layer contains tetracoordinated aluminum atoms and hexacoordinated aluminum atoms existing in a higher proportion than the tetracoordinated aluminum atoms.

2. The developer carrying member according to claim 1, wherein a volume resistance is greater than 2×

10⁴ Ω and

smaller than 5×

10⁶ Ω

.

3. The developer carrying member according to claim 1, wherein a volume resistivity of the surface layer is no smaller than 10¹¹ Ω

cm and no larger than 10¹⁴ Ω

cm.

4. The developer carrying member according to claim 1, wherein a thickness of the surface layer is no smaller than 0.05 μ

m and no larger than 1.0 μ

m.

5. The developer carrying member according to claim 1, wherein a thickness of the surface layer is no smaller than 0.1 μ

m and no larger than 0.5 Ω

m.

6. The developer carrying member according to claim 1, wherein an Asker-C hardness is higher than 30 degrees and lower than 80 degrees.

7. The developer carrying member according to claim 1, wherein the developer is a single component non-magnetic toner.

8. A developing assembly comprising:

a developer container housing a developer; and

the developer carrying member according to claim 1.

9. A process cartridge that can be attached to a main body of an image forming apparatus detachably in order to perform an image formation process, comprising:

an image bearing member capable of bearing a developer image; and

the developer carrying member according to claim 1, which forms the developer image by developing an electrostatic latent image on the image bearing member.

10. An image forming apparatus comprising:

an image bearing member capable of bearing a developer image;

the developer carrying member according to claim 1, which forms the developer image by developing an electrostatic latent image on the image bearing member; and

applying means for applying a voltage to the developer carrying member.