Patent · US Expired

Dry type toner for electrophotography

US5061588A · kind A · utility

23Cited by
4References
17Claims
0Family size

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Key dates

Filing dateApr 14, 1989
Grant dateOct 29, 1991
Priority date
Expiry dateApr 14, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/105
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A dry type toner for electrophotography is disclosed which comprises as the main components (a) a coloring agent; and (b) a polyol resin serving as a binder agent in an effective amount, the polyol resin being prepared by subjecting a bisphenol-type epoxy resin containing epoxy groups, which may contain secondary hydroxyl groups, to reaction steps (1), (2) and (3), or steps (2) and (3), in any sequential combination, until substantially no epoxy groups remain in the polyol resin, wherein the reaction step (1) comprises a step of causing the epoxy groups in the bisphenol-type epoxy resin to react with a primary amine; the reaction step (2) comprising a step of causing the epoxy groups to react with a compound containing one active hydrogen capable of reacting with the epoxy groups; and the reaction step (3) comprising a step of esterifying at least part of the secondary hydroxyl groups or hydroxyl groups produced in the bisphenol-type epoxy resin by reaction step (1) and/or reaction step (2) by use of an esterifying agent.

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