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:
Aug. 31, 1976
Filed:
Nov. 05, 1975
Applicant:
Inventor:
Maurice Grelat, Bettingen, CH;
Assignee:
Ciba-Geigy AG, Basel, CH;
Primary Examiner:
Int. Cl.
CPC ...
C07C / ; C07C / ;
U.S. Cl.
CPC ...
260378 ;
Abstract
A process for the manufacture of 1,4-diamino-5-nitroanthraquinone from 1,4-diaminoanthraquinone by nitration with mixed nitric and sulphuric acid, before which nitration a masking of the two amino groups to form 1,9-4,10-anthraquinone disulphonimide takes place, this intermediate being in turn split by hydrolysis after the nitration, which process comprises carrying out the masking of the 1,4-diaminoanthraquinone to form the 1,9-4,10-anthraquinone-disulphonimide with liquid sulphur trioxide and carrying out the entire nitration process by using liquid solvents which are inert towards the reactants.