Patent · US Expired

Negatively chargeable toner for use in dry electrophotography

US4883735A · kind A · utility

21Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 25, 1988
Grant dateNov 28, 1989
Priority date
Expiry dateJan 25, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/08795
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A negatively chargeable toner for use in dry electrophotography, said toner comprising (A) a resinous binder composed of at least one resin selected from copolymers of styrene and/or alpha-methylstyrene with alkyl (meth)acrylates, (B) 2 to 10 parts by weight, per 100 parts by weight of the resinous binder, of a copolymer containing a sulfonic acid group, said copolymer having a weight average molecular weight of from 2,000 to 15,000 and composed of 80 to 98% by weight of recurring units represented by the formula ##STR1## wherein R.sub.1 represents a hydrogen atom or a methyl group, and 20 to 2% by weight of recurring units represented by the formula ##STR2## and (C) a coloring agent.

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