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. 01, 1988
Filed:
May. 30, 1986
Applicant:
Inventors:
Stephen Y Lin, Wausau, WI (US);
Lin H Hoo, Schofield, WI (US);
Assignee:
Reed Lignin Inc., Rothschild, WI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08H / ;
U.S. Cl.
CPC ...
530501 ;
Abstract
Disclosed herein are sulfonated ligno-aminodicarboxylic acid and the salts thereof of the formula ##STR1## wherein X is an alkali cation, such as sodium, potassium, lithium, and ammonium, and Lignin denotes the polymeric sulfonated lignin material derived from commercial pulping of wood, straw, corn stalks, bagasse and the like. The dicarboxylic acid is made by a three-step process: (1) amination with ammonia and formaldehyde; (2) cyanomethylation with formaldehyde and sodium cyanide; and (3) hydrolysis of nitrile to carboxylic acid. The sulfonated ligno-aminodicarboxylic acid and its salts are useful as metal complexing agents.