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:
Sep. 08, 1992
Filed:
Feb. 28, 1991
Applicant:
Inventors:
Detlef-Ingo Schutze, Cologne, DE;
Dietmar Muller, Cologne, DE;
Assignee:
Bayer Aktiengesellschaft, Leverkusen, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
546 37 ;
Abstract
Brilliant and easily dispersible perylene-3,4,9,10-tetracarboxydiimide pigments of high color strength and N-alkyl derivatives thereof having 1 to 4 carbon atoms per alkyl group can be prepared by subjecting finely divided crude pigments to a treatment by means of a mixture of water and an organic solvent from the class of alcohols, ketones, carboxylic acids or carboxylic esters.