Semiconductor rubber composition and semicondctive rubber roller

• US 20060284142A1
• Filed: 04/10/2006
• Published: 12/21/2006
• Est. Priority Date: 06/20/2005
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Rubber Industries Limited
• Inventors: Mizumoto, Yoshihisa
• Granted Patent: US 7,641,816 B2
• Time in Patent Office: Days
• US Class Current: 252/500
• CPC Class Codes: G03G 15/0818 characterised by the structure of the donor member, e.g. surface properties
• CPC Class Codes: Y10T 428/1386 Natural or synthetic rubber or rubber-like compound containing
• CPC Class Codes: Y10T 428/139 Open-ended, self-supporting conduit, cylinder, or tube-type article

Abstract

A semiconductive rubber composition contains copolymerized rubber containing ethylene oxide; chloroprene rubber; and acrylonitrile-butadiene rubber. A conductive rubber roller has a conductive rubber layer composed of the semiconductive rubber composition on an outermost layer thereof.

Claims

1. A semiconductive rubber composition containing copolymerized rubber containing ethylene oxide;

chloroprene rubber; and

acrylonitrile-butadiene rubber.

2. The semiconductive rubber composition according to claim 1, wherein said copolymerized rubber containing said ethylene oxide essentially contains an epichlorohydrin copolymer.

3. The semiconductive rubber composition, according to claim 1, which shows ionic conductivity.

4. The semiconductive rubber composition, according to claim 2, which shows ionic conductivity.

5. The semiconductive rubber composition, according to claims 1, wherein a mixing amount of a copolymerized rubber containing ethylene oxide is smaller than that of acrylonitrile-butadiene rubber;

and a mixing amount of chloroprene rubber is smaller than that of said acrylonitrile-butadiene rubber.

6. The semiconductive rubber composition according to claims 1, wherein a compression set is not less than 1% nor more than 10%;

a hardness measured in accordance with JIS A is not less than 50 degrees nor more than 63 degrees; and

a maximum elongation is not less than 260%.

7. A conductive rubber roller having a conductive rubber layer composed of a semiconductive rubber composition described in claim 1 on an outermost layer thereof.

8. The conductive rubber roller, according to claim 7, having an oxide film formed on a surface thereof;

and a friction coefficient of said surface is in a range of 0.1 to 1.5.

9. The conductive rubber roller, according to claim 7, which is used as a developing roller in an image-forming mechanism of an electrophotographic apparatus.

10. The conductive rubber roller, according to claim 8, which is used as a developing roller in an image-forming mechanism of an electrophotographic apparatus.