Electrostatic toner comprising thermoplastic resin binder for nigrosine base salt
US4525445A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 1984 |
| Grant date | Jun 25, 1985 |
| Priority date | — |
| Expiry date | Apr 11, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/0914
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A particulate composition of matter for magnetic brush development of electrostatic charge patterns, adapted upon mixing with magnetic carrier particles to acquire a net positive charge, which contains colorant material and thermoplastic resin binder, the colorant material comprising a salt formed from a nigrosine base and at least one carboxylic acid containing one or two carboxylic acid groups and having from 2 to 26 carbon atoms, wherein the nigrosine salt is dispersed as particles in the thermoplastic resin binder which contains a polyester derived from fumaric acid or a mixture of at least 95 mol % fumaric acid and the balance isophthalic acid and a polyol blend of propoxylated bisphenol. The charge pattern is developed by contacting the same under the influence of an applied magnetic field with a mixture of magnetic carrier particles and the particulate composition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.