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:
Jun. 23, 1998
Filed:
Feb. 10, 1997
Applicant:
Inventors:
Assignee:
Huels Aktiengesellschaft, Marl, DE;
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528227 ; 204155 ; 204554 ; 528482 ;
Abstract
A process for the preparation of a condensation resin of low catalyst content from a ketone and an aldehyde comprising reacting the ketone and aldehyde in a polycondensation reaction in an aqueous medium in the presence of a basic catalyst to form the resin, which is contaminated with alkali ions from the basic catalyst, and then exposing the resin to an electrical field in a cell demarcated by ion-selective membranes permeable to the alkali ions whereby alkali ions are caused to migrate out of the resin through the membranes. Also, a process for the removal of alkali from condensation resins as described above.