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:
Aug. 14, 1979
Filed:
Jun. 23, 1977
Werner Henne, Wuppertal, DE;
Gustav Dunweg, Wuppertal, DE;
Werner Schmitz, Wuppertal, DE;
Raimund Pohle, Wuppertal, DE;
Friedrich Lawitzki, Wuppertal, DE;
Akzo N.V., Arnhem, NL;
Abstract
A dialyzing membrane, especially for hemodialysis, formed as a hollow fiber, tubular foil or flat sheet by regeneration of cellulose from a cuprammonium solution, the membrane comprising at least two firmly adhered cellulosic layers including at least one dialyzing layer consisting essentially of a semipermeable regenerated cellulose and at least one adsorbent layer consisting of said regenerated cellulose containing embedded therein fine particles of an adsorbent material in an amount of up to 95% by weight with reference to the dry weight of the adsorbent layer, preferably 1 to 90% and especially 20 to 70% by weight, when the adsorbent layer is part of a hollow fiber structure. The dialyzing membrane of the invention is produced by a method requiring at least two cuprammonium cellulose solutions, one of which is free of adsorbent particles and another of which contains a suspension of adsorbent particles, the different solutions being spun from adjacent spinning slots for immediate layer to layer contact and then introduced over a short air gap into a coagulating or precipitating bath to entrap the adsorbent particles in the spun layer in which the particles were originally suspended. Isopropyl myristate is particularly advantageous as a liquid filler for the axial duct or canal of a hollow membrane.