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:
Mar. 08, 1977
Filed:
Aug. 19, 1975
Applicant:
Inventors:
Tatsumi Kobayashi, Kurashiki, JA;
Yutaka Takakura, Kurashiki, JA;
Sadafumi Yoshino, Kurashiki, JA;
Yoshiaki Fukuda, Kurashiki, JA;
Assignee:
Nippon Soda Company Limited, Tokyo, JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ; C07C / ;
U.S. Cl.
CPC ...
2604 / ;
Abstract
Diaminomaleonitrile which is produced by the tetramerization of hydrogen cyanide is purified by heating a crude diaminomaleonitrile in an inert liquid or in an inert atmosphere at a temperature of 90.degree. to 140.degree. C, preferably 100.degree. to 120.degree. C, and then extracting pure diaminomaleonitrile having a purity of about 99% from said heated crude diaminomaleonitrile with a solvent.