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:
Oct. 19, 2004
Filed:
Feb. 24, 2003
Michael Stanek, Linz, AT;
Regina Schitter, Linz, AT;
Gerhard Steinbauer, Enns, AT;
Gerald Summer, Linz, AT;
Peter Hildebrand, Linz, AT;
DSM Fine Chemicals Austria Nfg GmbH & Co KG, Linz, AT;
Abstract
The invention relates to a washing process for cleaning polymers containing N or amine, ammonium or spirobicyclic ammonium groups, comprising cationic groups containing N, in addition to suitable counterions, whereby the gelled-out polymers are obtained through polymerization and cross-linking by a) adding a base which is partially or fully deprotonated, b) the partially or fully deprotonated polymers are washed, then c) optionally, are reprotonated in an organic solvent or in an organic solvent/water mixture by adding an acid, whereupon d) optionally, they are washed in an organic solvent or an organic solvent/water mixture in order to shrink the gels and optionally, e) in connection with step c) or d), the steps a)-c) or -d) are repeated.