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:
Jan. 06, 1981
Filed:
Sep. 08, 1978
Applicant:
Inventor:
Heinz Herrmann, Wiesbaden, DE;
Assignee:
Hoechst Aktiengesellschaft, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
430115 ; 526264 ;
Abstract
This invention relates to an improvement in a liquid developer for the development of electrostatic charge images, comprising an electrically insulating carrier liquid in which pigments or dyestuffs, resinous binders, a polarity control agent, and conventional additives are dispersed or dissolved, the improvement that the polarity control agent is a copolymer which is soluble in the carrier liquid and is composed of 1 to 50 percent by weight of N-vinyl-2-pyrrolidone and 50 to 99 percent by weight of a methacrylic acid ester.