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:
Jun. 10, 1980
Filed:
Nov. 10, 1977
Applicant:
Inventors:
Wolfgang Eisfeld, Ludwigshafen, DE;
Walter Disteldorf, Ludwigshafen, DE;
Albert Hettche, Ludwigshafen, DE;
Assignee:
BASF Aktiengesellschaft, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
260546 ;
Abstract
Pure halonaphthalic acid anhydrides are prepared from haloacenaphthenes by oxidation with nitric acid in a mixture of aliphatic carboxylic acid, water and nitric acid in the presence of vanadate, with or without further metal salts, at an elevated temperature and the reaction product is isolated and subjected to an oxidative after-treatment with hypochlorite in aqueous solution at a pH of from 9 to 12 at an elevated temperature. The products are intermediates for the manufacture of optical brighteners.