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:
Aug. 29, 1978
Filed:
Nov. 07, 1977
Applicant:
Inventors:
Hans Frischkorn, Hofheim am Taunus, DE;
Gunter Rosch, Bad Soden amTaunus, DE;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C09K / ; C07D / ;
U.S. Cl.
CPC ...
25230128 ; 2603 / ;
Abstract
Compounds of the formula ##STR1## wherein R.sup.1 to R.sup.8 each mean, independent from one another, a hydrogen atom or a non chromophoric substituent, R.sup.9 means a hydrogen atom, an alkyl group, a halogen atom, preferably a chlorine or bromine atom, an optionally functionally modified carboxy or sulfo group. They are prepared by reacting 1 mol of 1,7-naphthalene dicarboxylic acid or its acid chloride with 2 mols of an o-aminophenol and subsequent cyclization of the di-N,N'-acyl compounds obtained in the first step. These compounds are valuable optical brighteners.