Rubber composition, sheet conveying roller, and image forming apparatus

• US 9,637,623 B2
• Filed: 03/10/2014
• Issued: 05/02/2017
• Est. Priority Date: 03/29/2013
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Rubber Industries Limited
• Inventors: Mine, Akihiro, Tamura, Toshihiro, Hyodo, Takehiko
• Primary Examiner(s): Vaughan, Jason L
• Application Number:
  US14/202,692
• Publication Number:
  US 20140296049A1
• Time in Patent Office: 1,149 Days
• Field of Search: 492 56, 492 59
• CPC Class Codes: C08L 19/00 Compositions of rubbers not provided for in groups C08L7/00 - C08L17/00
• CPC Class Codes: G03G 15/6511 Feeding devices for picking up or separation of copy sheets
• CPC Class Codes: G03G 15/6529 Transporting G03G15/6555 takes precedence
• CPC Class Codes: G03G 15/6552 Means for discharging uncollated sheet copy material, e.g. discharging rollers, exit trays
• CPC Class Codes: G03G 2215/00683 Chemical properties

Abstract

A rubber composition contains a higher ethylene content EPDM and a lower ethylene content EPDM as a rubber component. The proportion of the higher ethylene content EPDM is 30 to 80 mass % based on the overall amount of the rubber component. The rubber composition is less susceptible to reduction in friction coefficient μ and has a proper hardness, a smaller permanent elongation and an excellent abrasion resistance after crosslinking. Therefore, the rubber composition is suitable for a sheet conveying roller and an image forming apparatus incorporating the sheet conveying roller.

Claims

1. A rubber composition for forming a sheet conveying roller, comprising a rubber component, and a peroxide crosslinking agent,

wherein the rubber component consists of:

a first portion of an ethylene propylene diene rubber having an ethylene content of not less than 62%; and

a second portion of an ethylene propylene diene rubber having an ethylene content of not greater than 55%,

wherein the first portion of the ethylene propylene diene rubber is present in a proportion of not less than 30 mass % and not greater than 50 mass % based on an overall amount of the rubber component.

2. The rubber composition according to claim 1, further comprising a crosslinking assisting agent.

3. The rubber composition according to claim 2, which provides a crosslinked product having a permanent elongation of not greater than 12%.

4. The rubber composition according to claim 1, which provides a crosslinked product having a permanent elongation of not greater than 12%.

5. A sheet conveying roller comprising a rubber composition according to claim 1.

6. An image forming apparatus comprising a sheet conveying roller according to claim 5.