Filter membrane and device
AssigneeGambro Lundia AB
InventorsBernd KRAUSE, Adriana BOSCHETTI-DE-FIERRO, Manuel VOIGT, Johannes GECKELER, Ferdinand SCHWEIGER
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Abstract
The present disclosure relates to a microporous hollow fiber filter membrane having a large inner diameter and a thin wall. The fiber can be used for sterile filtration of liquids or removal of particles from liquids. The disclosure further relates to a method for producing the membrane and a filter device comprising the membrane.
Claims21
A porous hollow fiber membrane having a sponge-like structure, the membrane comprising a mean flow pore size, determined by porometry, which is larger than 0.2 μm;
- the membrane comprising polyethersulfone and polyvinylpyrrolidone;
- and wherein the membrane comprises
- an inner diameter of from about 2,300 μm to about 4,000 μm;
- and
- a wall strength of from about 150 μm to about 500 μm;
- wherein the inner diameter and the wall strength have a ratio of greater than about 10.
A continuous solvent phase inversion spinning process for preparing a porous hollow fiber membrane, said process comprising the steps of
- a) dissolving at least one polyethersulfone, at least one polyvinylpyrrolidone, and, optionally, a polymer bearing cationic charges, in N-methyl-2-pyrrolidone to form a polymer solution;
- b) extruding the polymer solution through an outer ring slit of a nozzle with two concentric openings into a precipitation bath;
- simultaneously
- c) extruding a center fluid through the inner opening of the nozzle;
- d) washing the membrane obtained;
- and subsequently
- e) drying the membrane;
- f) sterilizing the membrane with steam or gamma radiation subsequently to drying;
- wherein the polymer solution comprises from about 15% to about 20 wt %, relative to the total weight of the polymer solution, of polyethersulfone, and from about 10% to about 15 wt %, relative to the total weight of the polymer solution, of polyvinylpyrrolidone.
(canceled)
Dependencies are inferred from the claim text.