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. 21, 1987
Filed:
Oct. 02, 1984
Bernd Dill, Rheinfelden, DE;
Ciba-Geigy AG, Basel, CH;
Abstract
The invention relates to a process for the preparation of anthraquinone imides by condensing vattable anthraquinone compounds which contain at least one primary amino group with aromatic halogen compounds, in an organic solvent and at elevated temperature in the presence of a base and a copper catalyst. The process comprises first carrying out the condensation until a reaction of 60-95% has taken place, and then subjecting the reaction mixture, without isolating the reaction product, to an aftertreatment at a temperature which is 5.degree. to 60.degree. C. above the initial temperature of the condensation. This process permits the anthraquinone imides to be obtained in increased yield and additionally provides products with improved qualities. The intermediates so obtained can be further processed to vat dyes.