Sumitomo Rubber Industries Limited

Toshihiro Tamura

Akihiro Mine

Takehiko Hyodo

Hirokazu Nishimori

Masahiro Yoshizato

Hideyuki Okuyama

Toshiyuki Hirai

Keishi Yamamoto

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 &#x3bc; 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.

Rubber composition, sheet conveying roller, and image forming apparatus

A sheet feeding member is provided, which is made of a thermoplastic elastomer composition comprising: a base polymer including a polyurethane thermoplastic elastomer and a polyester thermoplastic elastomer; and at least one ion conductive agent selected from the group consisting of a quaternary ammonium salt and a lithium salt/polyol, wherein the ion conductive agent is present in a proportion of 0.2 to 4 parts by mass based on 100 parts by mass of the base polymer in the thermoplastic elastomer composition.

Sheet feeding member

The inventive sheet conveying roller has a double-layer structure including a tubular outer layer and an inner layer inserted directly in the tubular outer layer without the intervention of an adhesive agent. The sheet conveying roller includes a roller body of a double-layer structure including a tubular outer layer () of a urethane thermoplastic elastomer and an inner layer () of a rubber such as IIR inserted directly in the tubular outer layer () without the intervention of an adhesive agent. The outer layer () has a Type-A Durometer hardness of not less than 40 and not greater than 65, and the inner layer () has a Type-A Durometer hardness of greater than 10 and not greater than 25.

Sheet conveying roller

The paper feed roller according to the present invention is made of a thermoplastic elastomer composition containing an ester thermoplastic elastomer urethane or an ether thermoplastic elastomer urethane (E) having microrubber hardness (type A) of not less than 60 and not more than 80 and a plasticizer (P) in a mass ratio E/P of 70/30 to 50/50.

Paper feed roller

The inventive sheet conveying roller includes a plurality of linear projections provided on an outer peripheral surface of a roller body of an elastic material and each having a generally right-angled triangular cross section which includes a hypotenuse edge and an adjoining edge provided on a forward side and on a rearward side, respectively, with respect to a roller body rotation direction, the adjoining edge aligning with a line perpendicular to a center axis of the roller body. The linear projections are rounded with the hypotenuse edges and the adjoining edges thereof connected to each other by curves as seen in section, and provided integrally with the roller body to be equidistantly arranged on the outer peripheral surface of the roller body.

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Kobe, Japan

Toshihiro Tamura