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. 09, 2007
Filed:
Jul. 08, 2003
Applicants:
Fridolin Bäbler, Teresópolis, BR;
Hans Rudolf Merstetter, Chadds Ford, PA (US);
Inventors:
Fridolin Bäbler, Teresópolis, BR;
Hans Rudolf Merstetter, Chadds Ford, PA (US);
Assignee:
Ciba Specialty Chemicals Corporation, Tarrytown, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D 471/02 (2006.01); C09B 48/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
The present invention relates to a process of preparing quinacridone by oxidizing a 6,13-dihydroquinacridone salt corresponding to the quinacridone pigment with hydrogen peroxide as the oxidizing agent in the presence of 2,7-anthraquinone disulfonic acid as catalyst. The inventive process is economical and environmentally friendly and yields high performance quinacridone pigments in a high yield.