The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1985
Filed:
Apr. 11, 1984
Pierre R De Roo, Schoten, BE;
Serge M Tavernier, Schoten, BE;
Agfa-Gevaert N.V., Mortsel, BE;
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.