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:
Apr. 09, 1985
Filed:
Jul. 27, 1983
Applicant:
Inventors:
Assignee:
Sumitomo Chemical Company, Limited, Osaka, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
260371 ;
Abstract
A process for the production of 1,4-diaminoanthraquinone-2-sulfonic acid or a salt thereof is disclosed, comprising reacting 1-amino-4-bromoanthraquinone-2-sulfonic acid or its salt with liquid ammonia in the presence of a copper catalyst wherein the reaction is carried out in the presence of an inert organic solvent, e.g., n-heptane and cyclohexane. In this process, crystals of the desired product do not substantially deposit on reactor walls, and distillation recovery of ammonia can be performed easily without causing deterioration of the desired product. 1,4-Diaminoanthraquinone-2-sulfonic acid or salt thereof is a useful intermediate for the preparation of, e.g., anthraquinone dyes.