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:
Mar. 21, 1989
Filed:
Sep. 01, 1988
Applicant:
Inventors:
Assignee:
Canadian Patents and Development Limited, Ottawa, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ;
U.S. Cl.
CPC ...
21050029 ; 264 41 ; 264298 ; 264D / ; 264D / ;
Abstract
There is provided a method of manufacturing cellulose membranes with pore radii less than 30.times.10.sup.-10 m, suitable for reverse osmosis applications. The method comprises dissolving a cellulosic material in a DMSO/PF solvent at a temperature about 125.degree. C. for about 90 min., cooling and casting the solution at room temperature, evaporating the solvent at a temperature of 140.degree.-180.degree. C. and gelling the resulting membrane in a protic solvent, e.g. ethanol or water.