Developing member

• US 8,655,238 B2
• Filed: 04/11/2013
• Issued: 02/18/2014
• Est. Priority Date: 12/09/2011
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Kusaba, Takashi, Urushihara, Shohei, Uno, Masashi, Sugiyama, Ryo
• Primary Examiner(s): HYDER, G.M. ALI
• Application Number:
  US13/861,271
• Publication Number:
  US 20130223892A1
• Time in Patent Office: 313 Days
• Field of Search: 399/279, 399/286
• US Class Current: 399/286
• CPC Class Codes: G03G 15/08 using a solid developer, e.g. powder developer
• CPC Class Codes: G03G 15/0818 characterised by the structure of the donor member, e.g. surface properties

Abstract

Provided is a developing roller including elastic layer and resin layer adhered to each other and having an appropriately resistance, thereby suppressing fogging. The developing member comprises a mandrel; an elastic layer; and a resin layer, wherein: the resin layer comprises polyurethane resin obtained by isocyanate and polyol; and the elastic layer includes cured silicone rubber composition comprising (a)-(d):

• (a) organopolysiloxane having two or more alkenyl groups bonded to silicon atom and having methyl group as a group other than the alkenyl bonded to the silicon;
• (b) organopolysiloxane having three or more hydrogen atoms bonded to silicon atom and having methyl group as a group bonded to the silicon;
• (c) carbon black;
• (d) organopolysiloxane represented by formula (1) and having Mw of 18,000-110,000 and Mw/Mn of 1.0-2.0 (R¹ represents alkenyl group, R² represents functional group reacting with isocyanate, and n represents an integer of 1 or more).

Claims

1. A developing member, comprising in the following order:

a mandrel;

an elastic layer; and

a resin layer,

wherein;

the resin layer comprises a polyurethane resin obtained by reacting an isocyanate compound with a polyol compound; and

the elastic layer comprises a cured product of an addition polymerization type silicone rubber composition comprising the following (a) to (d);

(a) an organopolysiloxane having two or more alkenyl groups bonded to a silicon atom in one molecule and having a methyl group as a group other than the alkenyl groups bonded to the silicon atom;

(b) an organopolysiloxane having three or more hydrogen atoms bonded to a silicon atom in one molecule and having a methyl group as a group bonded to the silicon atom;

(c) carbon black; and

(d) an organopolysiloxane represented by the following formula (1) and having a weight average molecular weight Mw of 18,000 or more and 110,000 or less and a molecular weight distribution Mw/Mn, where Mn represents a number average molecular weight, of 1.0 or more and 2.0 or less;

2. The developing member according to claim 1, wherein the functional group capable of reacting with an isocyanate group in the (d) component, comprises a group selected from the group consisting of a hydroxyl group, an alkoxyl group, an amino group, and a thiol group.

3. The developing member according to claim 2, wherein the functional group capable of reacting with an isocyanate group in the (d) component, comprises an alkoxyl group, and the alkoxyl group comprises one of a methoxy group and an ethoxy group.

4. The developing member according to claim 1, wherein the (b) component, has a weight average molecular weight of 300 or more and 100,000 or less.

5. The developing member according to claim 1, wherein the elastic layer has a volume resistivity of 1×

10⁴ Ω

·

cm or more and 1×

10⁷ Ω

·

cm or less.

6. An electrophotographic apparatus, comprising:

a photosensitive member; and

a developing member placed to abut on the photosensitive member,

wherein the developing member comprises the developing member according to claim 1.