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. 25, 1976
Filed:
Dec. 11, 1973
Applicant:
Inventors:
Assignee:
Joh. A. Benckiser GmbH, Ludwigshafen, DT;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07F / ;
U.S. Cl.
CPC ...
2605025 ;
Abstract
Substantially pure amino methylene phosphonic acids, such as ethylene diamine tetra-(methylene phosphonic acid), nitrilo tris-(methylene phosphonic acid), and others are obtained in a high yield by reacting .alpha.-amino mono- or polycarboxylic acids which are substituted at their amino nitrogen atom, or their alkali metal salts with phosphorous acid and/or a phosphorus trihalogenide, preferably phosphorus trichloride in the presence or absence of an inert diluent.