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:
Nov. 29, 1988
Filed:
Jul. 07, 1987
Applicant:
Inventor:
Ulf Sjostrand, Karlskoga, SE;
Assignee:
Nobel Kemi AB, Karlskoga, SE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
562453 ; 534674 ; 260508 ;
Abstract
The disclosure relates to a method of producing 5-amino salicylic acid from salicylic acid, with sulphanilic acid as the recyclable auxiliary chemical. The method according to the present invention includes linking between the diazonium salt of the sulphanilic acid and the salicylic acid, followed by a splitting by hydrogenation with hydrogen gas and catalyst, and selective precipitation of the desired product.