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. 13, 1984
Filed:
Feb. 10, 1982
Applicant:
Inventors:
Assignee:
Degussa Aktiengesellschaft, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
546245 ; 548499 ; 548535 ; 562443 ; 562444 ; 562445 ; 562446 ; 562503 ; 562507 ; 562557 ; 562571 ; 562573 ; 562574 ; 562575 ;
Abstract
Aqueous solutions of sodium salts of .alpha.-aminocarboxylic acids practically free of foreign salts are produced by saponifying the corresponding hydantoin at a temperature between 110.degree. C. and 180.degree. C. with a mixture, in each case based on the hydantoin, of 1 equivalent of sodium hydroxide and 2 equivalents of calcium oxide or hydroxide, separating off the precipitated calcium carbonate after the end of the saponification and concentrating the aqueous sodium salt solution remaining to drive off the ammonia contained therein.