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:
Feb. 05, 1985
Filed:
Aug. 19, 1983
Applicant:
Inventors:
Heinz Herrmann, Wiesbaden, DE;
Hans-Joachim Schlosser, Wiesbaden, DE;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
430115 ; 430137 ; 430100 ;
Abstract
An electrophotographic liquid developer is disclosed which is useful in the development of negatively charged charge images. The developer comprises an electrically insulating carrier liquid of high electrical resistivity and a low dielectric constant, a pigment or dye, a resinous binder, a charge controller comprising a copolymer of N-vinyl-2-pyrrolidone and a methacrylic acid ester, and a poly-N-vinyl-2-pyrrolidone which has been alkylated with an .alpha.-olefin. A process for producing the liquid developer is also disclosed.