Process for the partial modification of porous, hydrophilitic filter membranes, of filter membranes treated in such manner and filter modules equipped with such filter membranes, especially filter cartridges

US6159369A · kind A · utility

Assignee

• Seitz-Filter-Werke GmbH und Co. · DE

Inventors

• Gerhard Strohm · Dexheim, DE
• Hans-Joachim Muller · Remscheid, DE
• Markus KIRSCHNER · Mainz, DE
• Udo Holzki · Wörrstadt, DE

Key dates

• Filing date: Jul 25, 1996
• Grant date: Dec 12, 2000
• Expiry date: Jul 25, 2016

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D65/003
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Process for the partial modification of porous, hydrophilitic filter membranes, of filter membranes treated in such manner and filter modules equipped with such filter membranes. When hydrophilic filter membranes are embedded in hydrophobic securing components of filter modules, the membrane filters are hydrophobized beyond the embedding area in an edge region, so that this edge region, that can no longer be wetted by water, forms an air by-pass when the filter modules are tested, rendering thus impossible that the filter modules can be tested. The novel process is intended to modify the edge regions in such a manner that, even after partial areas have been embedded in a hydrophobic polymer material, they remain porous and hydrophilic over the whole of their effective area. The porous filter membranes are soaked in a solution of hydrophilizing agent in the areas intended to be embedded, so that the filter membranes are saturated with solution in the thus predetermined areas, and the thus treated filter membranes are immediately washed and dried. Through this process, the modified edge regions are several times more hydrophilic than the untreated areas in the filter membranes, so th…