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:
Jan. 06, 1981
Filed:
May. 25, 1979
Robert Portmann, Pratteln, CH;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
The invention relates to a process for the preparation of azo dyes of the formula ##STR1## or mixtures thereof, in which Ar is a substituted or unsubstituted phenyl, naphthyl or aromatic heterocyclic radical and Y is a group of the formula --O-R, --S-R or ##STR2## in which R is a substituted or unsubstituted alkyl, aryl or heterocyclic radical and R.sub.1 and R.sub.2 independently of one another are hydrogen or a substituted or unsubstituted alkyl, aryl or heterocyclic radical, and the groups R.sub.1 and R.sub.2, together with the nitrogen atom to which they are bonded, can form a ring. The process comprises first coupling dimeric malonodinitrile with a diazo component and cyclizing the resulting intermediate with an alcohol, thioalcohol or amine.