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:
Nov. 17, 1992
Filed:
Jul. 26, 1991
/Peter Hanel, Bad Vilbel, DE;
Harald Helmrich, Frankfurt am Main, DE;
Metallgesellschaft Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
The process of making a multilayer membrane composed of a carrier layer, a porous supporting layer and a separating layer includes making a modified polyvinyl alcohol by decomposing a polyvinyl ester or ether until the proportion of the vinyl alcohol monomer units in the modified polyvinyl alcohol corresponds to that in a material consisting of 80 to 95% of the polyvinyl ester or ether and 20 to 5% of a polyvinyl alcohol obtained by completely decomposing the polyvinyl ester or ether; preparing a composite material consisting of the carrier layer and the porous supporting layer, preparing a dilute aqueous solution containing 1 to 10% by weight of the modified polyvinyl alcohol; preferably storing the dilute solution at temperatures from -10.degree. to +10.degree. C., preferably from 0.degree. to 5.degree. C., for 3 to 20 days, after storing, applying the dilute solution to the supporting layer of the composite material to coat the composite material with the modified polyvinyl alcohol; and after the applying, heating the composite material coated with the modified polyvinyl alcohol at a temperature of from 100.degree. to 180.degree. for 1 to 60 minutes.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile