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. 10, 1986
Filed:
Jun. 12, 1985
Hansjoerg Vollmann, Bad Soden, DE;
Heinz Herrmann, Wiesbaden, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
A liquid developer and a charge control substance for developing positively charged electrostatic charge images. The developer comprises an electrically insulating carrier liquid having a high resistance and a low dielectric constant and which contains a pigment or dye, a resinous binder, the charge control substance and conventional additives in dispersion or solution. The charge control substance is a negative-controlling graft copolymer soluble in an aliphatic hydrocarbon and is obtained by grafting a carboxylic acid N-alkenylamide onto polymers soluble in aliphatic hydrocarbons used as the carrier liquid. The carboxylic acid N-alkenylamide is a compound of the formula: ##STR1## in which R is hydrogen or C.sub.1 -C.sub.3 alkyl,