Sumitomo Rubber Industries Limited

Masahiro Yoshizato

Akihiro Mine

Toshihiro Tamura

Masashi Hamakubo

Toshiyuki Hirai

Hirokazu Nishimori

Munehiro Nishimoto

Keishi Yamamoto

Naoyuki Astoyoshi

There are provided: an electrically conductive thermoplastic elastomer composition which can be produced with higher productivity at lower costs by means of a simple arrangement and has excellent extrudability and a lower resistance required for a driving roller; a production method for the composition; a driving roller produced by employing the electrically conductive thermoplastic elastomer composition; and an image forming apparatus incorporating the driving roller. In the electrically conductive thermoplastic elastomer composition, 5 to 15 parts by mass of Ketjen black is finely dispersed in 100 parts by mass of a mixture of an ester type urethane thermoplastic elastomer and a plasticizer or in 100 parts by mass of a polyester thermoplastic elastomer. In the production method, the ingredient other than the Ketjen black is first kneaded, and then the Ketjen black is added to and further kneaded with the ingredient. The driving roller () is formed of the electrically conductive thermoplastic elastomer composition. The image forming apparatus incorporates the driving roller.

Electroconductive elastomer composition and manufacturing method therefor

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 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.

Sheet conveying roller and image forming apparatus

Growing community of inventors

Kobe, Japan

Masahiro Yoshizato