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:
Apr. 26, 1977
Filed:
Jul. 25, 1975
Applicant:
Inventors:
Donald S Johnson, Scotia, NY (US);
Howard M Relles, Rexford, NY (US);
Assignee:
General Electric Company, Schenectady, NY (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
2605 / ; 260 / ; 260 / ; 2603 / ; 2603 / ; 2603 / ; 2603463 ; 260516 ; 260546 ;
Abstract
Aromatic tetracarboxylic acids can be prepared by effecting reaction between a 4-nitro-N-alkylphthalimide with an aromatic dihydroxy compound in the presence of potassium carbonate as a catalyst and using dimethyl sulfoxide as a solvent.