CHARGING MEMBER AND ELECTROPHOTOGRAPHIC APPARATUS

• US 20130295330A1
• Filed: 07/02/2013
• Published: 11/07/2013
• Est. Priority Date: 02/06/2012
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kodama, Masataka, Sato, Taichi, Suzumura, Noriko, Doi, Noriyuki, Kurachi, Masahiro, Masu, Hiroki, Kuroda, Noriaki
• Granted Patent: US 9,081,321 B2
• Time in Patent Office: Days
• US Class Current: 428/147
• CPC Class Codes: C09D 183/06 containing silicon bound to oxygen-containing groups C09D183/12 takes precedence
• CPC Class Codes: G03G 15/02 for laying down a uniform charge, e.g. for sensitising; Corona discharge devices G03G15/14 takes precedence
• CPC Class Codes: G03G 15/0233 Structure, details of the charging member, e.g. chemical composition, surface properties
• CPC Class Codes: Y10T 428/24405 Polymer or resin [e.g., natural or synthetic rubber, etc.]

Abstract

There is provided a charging member having charging performance that is not easily changed even by long-term use.

The charging member includes an electro-conductive support, an elastic layer, and a surface layer. The elastic layer contains particles in such a manner that at least a part of the particles are exposed from the elastic layer, and thus a surface of the elastic layer is roughened. The particles are high-molecular-weight polyethylene particles. The surface of the elastic layer is covered with the surface layer in such a manner that the surface shape of the elastic layer is reflected in the surface shape of the charging member. The surface layer contains a high-molecular compound having a specific constitutional unit.

Claims

1. A charging member comprising:

an electro-conductive support,

an elastic layer containing electro-conductive particles dispersed in the elastic layer, and

a surface layer, wherein

the elastic layer holds polyethylene particles in such a manner that at least a part of the polyethylene particles are exposed from the elastic layer, and a surface of the elastic layer is roughened thereby,

the surface of the elastic layer is covered with the surface layer in such a manner that the surface shape of the elastic layer is reflected in the surface shape of the charging member, and wherein

the surface layer contains a high-molecular compound having a constitutional unit represented by formula (1);

2. The charging member according to claim 1, wherein the polyethylene particles are composed of a polyethylene having a weight-average molecular weight of two million or more.

3. The charging member according to claim 1, wherein the polyethylene particles are 5% by mass or more and 50% by mass or less with respect to the elastic layer.

4. The charging member according to claim 1, wherein the polyethylene particles have an average particle size of 10 μ

m or more and 40 μ

m or less.

5. The charging member according to claim 1, wherein the surface layer has an elastic modulus of 1,000 MPa or more and 20,000 MPa or less.

6. The charging member according to claim 1, wherein the ten-point height of irregularities of a surface of the surface layer is in the range of 5 to 30 μ

m.

7. The charging member according to claim 1, wherein the high-molecular compound is a crosslinked product of a hydrolyzed condensate of a hydrolyzable silane compound containing a compound represented by formula (10):

R₃₁—

Si(OR₃₂)(OR₃₃)(OR₃₄) 

 

formula (10)

(wherein in formula (10), R₃₂, R₃₃, and R₃₄ each independently represent an alkyl group having 1 to 4 carbon atoms; and

R₃₁ represents any one of formulae (12) to (15);

8. The charging member according to claim 7, wherein the hydrolyzable silane compound further contains a compound represented by formula (11):

R₆₃—

Si(OR₆₄)(OR₆₅)(OR₆₆) 

 

formula (11)

(wherein in formula (11), R₆₄, R₆₅, and R₆₆ each independently represent an alkyl group having 1 to 4 carbon atoms; and

R₆₃ represents an alkyl group having 6 to 10 carbon atoms or a phenyl group).

9. An electrophotographic apparatus comprising an electrophotographic photosensitive member, and a charging member arranged in contact with the electrophotographic photosensitive member,

wherein the charging member is the charging member according to claim 1.