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. 08, 1985
Filed:
Aug. 23, 1982
Karl Sommer, Konigstein, DE;
Norbert Armbrecht, Sulzbach, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
Water soluble trisazo dyestuffs of the formula ##STR1## in which A is 1-amino-8-naphthol-3,6-disulfonic acid or 1-amino-8-naphthol-4,6-disulfonic acid, or a mixture of these two compounds, and B is 1-(3'- or 4'-aminophenyl)-3-methyl-5-pyrazolone, a process for their manufacture by diazotizing component A and coupling it with 3,3'-dihydroxy-diphenylamine to give a monoazo dyestuff, reacting this dyestuff with diazotized component B to give a disazo dyestuff, and converting this dyestuff to the trisazo dyestuff by uniting it with diazotized 4-nitro-4'-amino-diphenylamine-2-sulfonic acid, or by operating as described while, however, changing the sequence of reaction of component B and 4-nitro-4'-amino-diphenylamine-2-sulfonic acid, and use of these dyestuffs for the dyeing of leather and fur.