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:
May. 26, 1992
Filed:
Apr. 15, 1991
Applicant:
Inventor:
Reinhold Kohlhaupt, Frankenthal, DE;
Assignee:
BASF Aktiengesellschaft, Ludwigshafen, DE;
Primary Examiner:
Int. Cl.
CPC ...
C09B / ;
U.S. Cl.
CPC ...
548457 ; 548458 ;
Abstract
A process for the purification of indigo comprises treating the indigo with sulfuric acid to give indigo sulfate, separating off and subsequently hydrolyzing the latter to re-form indigo, and then treating the dye with dilute hydrogen peroxide solution.
Kohlhaupt, Reinhold. (1992). Purification of indigo (U.S. Patent No. 5116997). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/5116997
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile