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:
Sep. 24, 1996
Filed:
Sep. 01, 1993
Hoechst AG, , DE;
Abstract
An ecologically and economically advantageous process for preparing a disazo pigment of the formula (I) or a mixture of said disazo pigments ##STR1## where D.sup.1 and D.sup.2 are identical or different and each is unsubstituted phenyl, phenyl with from 1 to 5 substituents, unsubstituted naphthyl, naphthyl with from 1 to 3 substituents, unsubstituted anthraquinonyl, anthraquinonyl with from 1 to 3 substituents, or a radical of a fused aromatic heterocycle which contains from 1 to 3 identical or different heteroatoms from nitrogen or oxygen and sulfur and is unsubstituted or has from 1 to 3 substituents, R.sup.1 and R.sup.2 are identical or different and each is hydrogen, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.5 -alkoxycarbonyl, nitro, cyano, phenoxy or trifluoromethyl, by azo coupling, comprises