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. 08, 1980
Filed:
Mar. 16, 1978
BASF Aktiengesellschaft, Rheinland-Pfalz, DE;
Abstract
In a process for the manufacture of 1-amino-2-bromo-4-hydroxyanthraquinone by hydroxylating previously prepared and isolated 1-amino-2,4-dibromoanthraquinone in sulfuric acid in the presence of boric acid at from 110.degree. to 130.degree. C., the improvememt that 1-aminoanthraquinone is brominated (from 1.5 to 2.1 moles of bromine per mole) in sulfuric acid of from 50 to 85 percent strength at from 80.degree. to 130.degree. C., the reaction mixture is brought to a concentration of from 96 percent strength sulfuric acid to 5 percent strength oleum by adding oleum; and the dibromo compound is then hydroxylated in the presence of boric acid. Very pure 1-amino-2-bromo-4-hydroxyanthraquinone, which can be used for all purposes, is obtained in a high yield.