US 4,906,371 AGranted

Filter element having microporous membrane

AssigneeCuno Incorporated

InventorMatthew J. Miller

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Abstract

A filter element containing a hydrophilic nylon microporous filter membrane having a preformed substantially non-porous sealing area of non-porous tape heat sealed to the membrane and a filter housing having preferably a hydrophobic thermoplastic sealing surface in thermoplastic sealing relationship with the sealing area. Preferably, the filter membrane is a pleated cylindrical membrane and the housing includes endcaps thereto. The preferred pleated cylindrical membrane is produced from an elongated porous filtration area longitudinally bordered by the substantially non-porous sealing areas. Such a membrane may be produced by applying a heat sealable non-porous tape along the longitudinal borders of the filtration area. The filter element is particularly useful for the filtration of aqueous liquids, particularly parenteral or body liquids.

Claims7

Dependent claims

A filter cartridge for filtration of aqueous liquids comprising:

(a) at least one end cap having a sealing surface made of hydrophobic thermoplastic material;
(b) a hydrophilic microporous nylon membrane in sheet form and having at least one edge;
(c) a netting layer on at least one side of said membrane;
(d) a non-porous heat-sealing tape extending along said at least one edge of said membrane and bonded thereto;
(e) said membrane and netting layer being folded to form a pleated filtering surface;
(f) said tape forming a sealing layer along at least one peripheral end of said filtering surface and being partially embedded and thermoplastically sealed within said sealing surface of said end cap;
and
(g) said tape substantially blocking micropores on said edge of said hydrophilic membrane to minimize adsorption of hydrophobic thermoplastic material along said peripheral end of said filtering surface during a thermoplastic sealing process when the filter cartridge is manufactured, so that aqueous liquids to be filtered can thoroughly and completely wet said hydrophilic membrane along said peripheral end of said filtering surface.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/339,928Filed 17 Apr 1989 · continuation
Priority: 28 May 1982
Granted: 6 Mar 1990
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

B01D 69/00
Semi-permeable membranes for separation processes or apparatus characterised by their form, structure
B01D 63/061
Tubular membrane modules: manufacturing thereof
B01D 63/067
Tubular membrane modules: with pleated membranes
B01D 65/003
Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes: membrane bonding or sealing