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. 17, 1997
Filed:
May. 03, 1996
Applicant:
Inventors:
Dietmar Kalz, Neunkirchen, DE;
Reinold Schmitz, Odenthal, DE;
Karl-Heinz Reinhardt, Leverkusen, DE;
Josef Schroder, Leverkusen, DE;
Stephan Michaelis, Odenthal, DE;
Assignee:
Bayer Aktiengesellschaft, Leverkusen, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C09B / ; C09B / ; C07C / ;
U.S. Cl.
CPC ...
552238 ; 552255 ; 552258 ; 552259 ;
Abstract
A process for the preparation of N,N'-disubstituted 1,4-diaminoanthraquinones has been found which is characterized in that 1,4-dihydroxyanthraquinones are reacted with aliphatic or aromatic amines in the presence of a hydroxycarboxylic acid as a condensation auxiliary.