摘要 |
PCT No. PCT/EP94/03627 Sec. 371 Date Jul. 25, 1996 Sec. 102(e) Date Jul. 25, 1996 PCT Filed Nov. 4, 1994 PCT Pub. No. WO95/14525 PCT Pub. Date Jun. 1, 1995Process 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 that the membrane areas in the filter modules in direct contact with the securing components still remain sufficiently hydrophilic.
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