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. 14, 1977
Filed:
Jul. 25, 1975
Gunter Gehrke, Cologne, DT;
Reinold Schmitz, Blecher, DT;
Bayer Aktiengesellschaft, Leverkusen, DT;
Abstract
The invention relates to the preparation of anthraquinone disperse dyestuffs from aqueous solutions containing anthraquinone-sulphonic acid mixtures, especially from appropriate waste waters by treating such solutions with chloric acid/hydrochloric acid or their salts or activated halogene, isolating the halogenoanthraquinones thereby obtained, subjecting them to dinitration and warming the dinitrohalogenoanthraquinones thus obtained with elementary sulphur in sulphuric acid optionally in the presence of boric acid. The reaction products are .beta.-halogenated diaminodihydroxyanthraquinones which are suitable for the dyeing of polyesters and polyamides in blue shades with good fastness properties.