Coated carrier for developing electrostatically charged images

US6068959A · kind A · utility

Assignees

• Hoechst Research & Technology · DE
• DEUTSCHLAND GMBH & CO. KG · DE

Inventors

• Toru Nakamura · Toyota, JP
• Toshimi Nishioka · Suita, JP
• Takuya Hoga · Saitama, JP
• Nobuyuki Kurokawa · Tokyo, JP
• Junichi Fukuzawa · Yokohama, JP
• Horst-Tore Land · Hofheim, DE
• Fredy Helmer-Metzmann · Essenheim, DE

Key dates

• Filing date: May 20, 1998
• Grant date: May 30, 2000
• Expiry date: May 20, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G03G9/1133
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

This invention relates to a coated carrier for development of an electrostatically charged image, comprising carrier core particles coated with a coating resin; wherein the coating resin at least includes a polyolefin resin having a cyclic structure; a polyolefin resin of a cyclic structure having an intrinsic viscosity (i.v.) of 0.25 dl/g or more, a heat distortion temperature (HDT) by DIN53461-B of 70 .degree. C. or higher, and a number average molecular weight of 7,500 or more and a weight average molecular weight of 15,000 or more, as measured by GPC, is contained in an amount of less than 50% by weight based on the entire coating resin; and the coating resin is used for coating in an amount of 1 to 30% by weight based on the carrier core particles. The present invention can obtain a coated carrier which exhibits high anti-spent toner effect and excellent charge control properties during development with a dry toner.