Patent · US Expired

Carrier for electrostatic image developer and process for the production thereof

US5376488A · kind A · utility

10Cited by
2References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 26, 1993
Grant dateDec 27, 1994
Priority date
Expiry dateApr 26, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/1138
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A carrier of developer for developing an electrostatic image and a method for producing the carrier are disclosed. The carrier comprises core particles each having a resin layer covering the surface of said core particle. The resin layer is formed by dry process in which the core particles are stirred together with fine resin particles with no solvent for the resin to form the resin layer on the surface of each core particle. The fine resin particles comprise a homopolymer or a copolymer comprising a fluorinated acrylate repeating unit and are formed by emulsified polymerization carried out in the presence of a surfactant comprising an alkylbenzene sulfonic compound, and the residual amount of the surfactant in the fine resin particles is within the range of from 60 ppm to 10,000 ppm. The carrier is improved in adhesion between the surface of the core and the resin layer and satisfactory in friction electricity providing capability.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.