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:
Mar. 23, 1993
Filed:
Aug. 28, 1991
Horst Langfeld, Grenzach-Wyhlen, DE;
Claudio Puebla, Grenzach-Wyhlen, DE;
Gunter Sereinig, Schopfheim, DE;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
A process for the preparation of azo dyes of formula ##STR1## wherein K is the radical of a coupling component of the benzene or naphthalene series or of the heterocyclic series, and the hydroxy group is attached to K adjacent to the azo group, X is hydrogen or nitro and M is an alkali metal ion, which process comprises coupling a diazo component of formula ##STR2## in the presence of one or more buffer mixtures and in the absence or presence of an alkali metal chloride, to a coupling component of formula ##STR3## in which formulae (2) and (3) K and X are as defined for formula (1). The present invention makes it possible to prepare the azo dyes in high yields.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile