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. 23, 1995
Filed:
Jun. 21, 1994
Sophie Suc, Oullins, FR;
Jacques Defaye, Saint Ismier, FR;
Andree Gadelle, Montbonnot Saint Martin, FR;
Jacques Kervennal, Lyon, FR;
Elf Atochem, S.A., Paris, FR;
Abstract
An amphoteric starch containing carboxyl and cationic groups characterized in that its carboxyl groups originate from the selective oxidation of the hemiacetal groups of the cationic starch and possibly of the hemiacetal groups of its products of acid hydrolysis. The process for producing the amphoteric starch consists in reacting a cationic starch in aqueous solution with hydrogen peroxide and hydrobromic acid or bromine, so as to oxidize selectively the hemiacetal groups of the cationic starch and, where appropriate, the hemiacetal groups of its products of acid hydrolysis, to give carboxyl groups.