Abstract: A process for the manufacture of porous structures comprises forming a dry mixture comprising a component providing primary separation capability, a component providing green strength reinforcement capability and, a component providing binding capability and selected from the group consisting of thermoplastic and thermosetting polymers; delivering the mixture to a suitable surface and building a desired thickness thereof; densifying the mixture into tile form desired for the porous structure; removing the densified porous structure from the surface; binding the component providing the primary separation capability by melting the mixture to a temperature of up to about 20.degree. C. higher than the melting point of any thermoplastic component providing binding capability.

Abstract: A process for the manufacture of porous structures comprises forming a dry mixture comprising a component providing primary separation capability, a component providing green strength reinforcement capability and, a component providing binding capability and selected from the group consisting of thermoplastic and thermosetting polymers; delivering the mixture to a suitable surface and building a desired thickness thereof; densifying the mixture into the form desired for the porous structure; removing the densified porous structure from the surface; binding the component providing the primary separation capability by melting the mixture to a temperature of up to about 20.degree. C. higher than the melting point of any thermoplastic component providing binding capability.

Abstract: Removable filter cartridge assemblies (10) for housings (28) having a removable member (101, 130) to provide access to the interior (102, 136) of the housing and an inlet (108, 134) and an outlet (109, 135) to and from the interior thereof (102, 136) comprising at least one filter cell (12) through which fluids are passed for filtration, the cell having a central aperture (18) therethrough for the passage of fluid, separate from the fluid within the housing; opposed disks of filtration media (16), spaced apart and defining upper (16U) and lower (16L) surfaces of the cell emanating radially from the central aperture; and, an outer peripheral edge (14) circumscribing the cell; first and second retainer ring members (22) securably disposed on the upper and lower surfaces of said filter cell, open to and concentric with the central aperture, said first retainer ring members being contiguous with the outlet of the housing; and lifting means (42, 50, 80, 90) communicable with one of the retainer ring members for mo

Abstract: Filter cartridge assemblies (10) comprising at least one filter cell (12) having an aperture (18) therethrough; a retainer ring (22) securably disposed on the filter cell and concentric with the aperture; and a lifting device (42, 50, 70, 80, 90) in communication with the retainer ring. A device for lifting and carrying a filter cell (12) comprising a retainer ring (22); and a lifting device (42, 50, 80, 90) in communication with the retainer ring. A method for the assembly of a cell-type filter cartridge device (10) comprising the steps of providing a filter housing (28) for at least one filter cell (12), the filter housing having a removable opening, an inlet and an outlet; providing at least one filter cell, the cell having an aperture (18) communicable with the outlet and a retainer ring (22) secured to the cell and providing a lifting device (42, 50, 80, 90); depositing the filter cell into the filter housing; and fastening the removable opening to the filter housing.

Abstract: A method for the production of a hydrolytically stable nylon membrane includes providing a nylon having at least about 0.9 moles of amino end groups per mole of nylon and preparing the nylon membrane therefrom. The membrane can be used in cartridges for use in filtration applications as may be necessary in the food and beverage industry as well as for the production of pharmaceuticals and the manufacture of electronic components. The membrane is capable of withstanding autoclaving and hot water sanitization without molecular dissociation regardless of its pore size, or thickness of the membrane, or the nylon solids content of the dope or, the temperature at which the dope is made.

Abstract: A method is provided of manufacturing a skinless, nylon microporous hollow fiber membrane. The method comprises the steps of providing a nylon polymer dope solution and a quench liquid capable of solidifying and forming micropores in an extruded nylon polymer dope solution to produce a skinless, microporous nylon membrane. The quench liquid is placed into a vessel and a tube is provided which has a top and a bottom outlet. The bottom outlet of the tube is partially submerged in the quench liquid, the tube vertically extending therefrom. A spinneret is provided which has an outlet adjacent the top of the tube. The chemical quench liquid is raised in the tube until it is in substantial contact with the spinneret outlet. The nylon polymer dope solution is extruded in the form of a hollow fiber through the spinneret outlet directly into the quench liquid.

Abstract: A process for the cross-flow filtration of a liquid comprising circulating the liquid tangential to a charge modified organic polymeric microporous filter membrane. Preferably, the membrane comprises an organic polymeric microporous filter membrane which has a micro-structure throughout the membrane and an amount of a charge modifying agent bound to substantially all of the membrance micro-structure without substantial pore size reduction or pore blockage.The process may be used for the filtration of liquids, particularly parenteral or biological liquids contaminated with charged particulate and for plasmapheresis, particularly in the form of hollow fiber tubes.

Abstract: A microporous nylon hollow fiber is prepared by extruding a nylon spinning solution through an annular slit of an orifice into a quench liquid while simultaneously introducing a core liquid into the inside hollow portion of the extruded spinning solution where the weighted densities of the spinning solution, quench liquid and the core liquid are regulated such that the average of the density of the core liquid and the spinning solution is about equal to the density of the quench liquid.

Abstract: A quench bath, for quenching and solidifying an extruded hollow porous fiber of a liquid polymer solution in a chemical quenching solution, includes a shallow quench bath of a length for the generally horizontal part of the extruded fiber travel in the bath. A vertical extension tube with its lower end beneath the surface of the bath liquid holds a spinneret through which the fiber is extruded. The spinneret is sealed in the tube above the height of the liquid in the shallow bath. A vacuum drawn in the tube raises the liquid up to the spinneret. Also, the vacuum may be drawn by disposing the spinneret in a sealing piston which is raised through the tube to draw the vaccum in the tube behind the piston.

Abstract: A dimensionally stabilized microporous polyamide membrane having enhanced flow characteristics comprised of a film forming organic polymeric material of low shrinkage prepared by drying the membrane, under conditions of restraint in the plane of the membrane to minimize the shrinkage until the membrane is essentially in a dried condition. A process is also described for preparing a microporous membrane designed to enhance incorporation and retention of a charge modifying resin for use as a charge modified filter media. The process comprises preparing a dope solution of a film forming polymer in a solvent system, directly casting the solution under the surface of a quenching medium comprising a non-solvent system for the polymer for a time sufficient to form micropores in the film, and drying the film while controlling the planar dimensions of the film during the drying.