Patent · US Expired

Nonmagnetic monocomponent negatively chargeable color developer

US5905011A · kind A · utility

8Cited by
13References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 12, 1998
Grant dateMay 18, 1999
Priority date
Expiry dateMar 12, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/0975
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A nonmagnetic monocomponent negatively chargeable color developer which has excellent light transmittancy for overhead projection transparencies, excellent transfer characteristics, charging characteristics, and durability is provided. The nonmagnetic monocomponent negatively chargeable color developer contains color toner particles that contain a chromatic color colorant, binder resin, and charge control agent, and an exterior additive added to the exterior of said toner particles. The binder resin is a linear polyester resin having a softening point of about 100.degree. to about 120.degree. C., the sum of the acid value and the hydroxyl value is about 20 to about 40 KOH mg/g, and the weight-average molecular weight/number-average molecular weight ratio is less than about 10. The charge controller is a boron compound having the general structural formula (A) below: ##STR1## wherein R.sub.1 and R.sub.8 is a substituted or nonsubstituted aryl groups; R.sub.2 and R.sub.4 is a member selected from the group consisting of hydrogen, alkyl group, substituted or nonsubstituted aryl group; X represents a cation, and n is an integer of either 1 or 2. The exterior additive is a hydrophobic s…

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