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. 18, 1980
Filed:
Apr. 10, 1979
Applicant:
Inventors:
Dietmar Nussbaumer, Gottingen, DE;
Horst Perl, Gottingen, DE;
Assignee:
Sartorius GmbH, Gottingen, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ; B01D / ; B29D / ;
U.S. Cl.
CPC ...
264 41 ; 2105 / ; 536 69 ; 536 76 ;
Abstract
An asymmetrical ultrafiltration membrane based on cellulose hydrate which may be dried without destructive shrinkage and which has been saponified without reduction in flow-through or separation performance is prepared by adding hydrophobic synthetic silicic acid to a casting solution based on cellulose triacetate optionally partially substituted by cellulose diacetate, and then casting the cellulose acetate membrane and saponifying to the cellulose hydrate form.