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. 18, 1994
Filed:
Mar. 30, 1993
Heinz-Dieter Sluma, Grossostheim, DE;
Robert Weinzenhofer, Erlenbach, DE;
Alfons Leeb, Kleinwallstadt, DE;
Karl Bauer, Dammbach, DE;
Akzo N.V., , NL;
Abstract
A multilayer membrane for separating gas mixtures includes a polymer supporting membrane with a voids volume of more than 50% and a coating of two or more separating layers made of two or more different polymers. A hollow capillary serving as the supporting membrane is guided through the central bore of a spinneret. The spinneret has one or several concentric annular slits and/or annular grooves, through each of which a solution of one of the polymers forming the separating layers is applied to the supporting membrane. The spinneret terminates in a sealed chamber in which the solvent or solvents of the polymer solutions is/are evaporated and removed. The coated supporting membrane is drawn out of the chamber and wound up, possibly following aftertreatment with heat and/or liquids.