Abstract: Filtration medium is formed of a mass of nonwoven melt blown support and filtration fibers which are integrally co-located with one another. The support fibers have, on average, relatively larger diameters as compared to the filtration fibers which are integrally co-located therewith. Preferably, the filtration medium is disposed within at least one annular zone of a filtration element, for example, a disposable cylindrical filter cartridge having an axially elongate central hollow passageway which is surrounded by the filtration media. A depth filter cartridge in accordance with the present invention may thus be formed having one or more additional filtration zones (which additional filtration zones may or may not respectively be provided with integrally co-located support fibers) in annular relationship to one another.

Abstract: A surface-modified fibrous material which includes hydrocarbon polymer fibers having cationic or anionic groups on the surfaces thereof and coated with a polyelectrolyte having a net charge opposite to that of the cationic or anionic groups on the surfaces of the fibers. The hydrocarbon polymer may be, by way of illustration, a polyolefin, such as polyethylene or polypropylene. The cationic or anionic groups may be carboxylic acid, sulfonic acid groups, or quaternary ammonium groups. Examples of polyelectrolytes include chitosan, poly(methacryloxyethyltrimethylammonium bromide), poly(acrylic acid), and poly(styrene sulfonate). Also disclosed is a method of making the surface-modified fibrous material. The surface-modified fibrous material may be used as a filtration medium for liquids.

Abstract: A filtration structure comprising a thermally bonded, wet laid, fibrous web and support is provided. The web is formed from bicomponent fiber comprising a structure-forming component and a heat-bondable component. Also provided is a filtration method using the filtration structure. Beneficially, the filtration structure may include microfiber.

Abstract: Composite articles are useful for separating mercury from fluids. The composite articles can be porous supports comprising an inert substrate having immobilized thereon finely divided gold optionally in combination with a tin salt coating. The porous support can be a particulate or porous fibrous webs. Alternatively, the composite articles can comprise a porous fibrous membrane having enmeshed therein the aforementioned porous supports which can be in particulate or fibrous forms. The method for separating elemental, ionic, or organic mercury in fluids comprises the step of contacting and passing a fluid containing mercury through a support comprising a porous, high surface area, inert substrate on which is immobilized finely divided elemental gold at a controlled rate for a time sufficient for the mercury to sorb to the elemental gold and to provide an immobilized gold-mercury amalgam on the support. If a tin salt also is immobilized on the inert substrate, mercury-tin salt can also be formed.

Abstract: Apparatus for washing-down serigraphical frames by means of a cleaning liquid comprises a sing-like unit having V or U-shaped ends, in which unit the serigraphical frames are placed, a scavenging hose with affixed brush, a filter section, a circulation pump, a sludge discharge system and a recirculation system for liquid. The filter section comprises a filter tray having V or U shaped cross-sections and a loosely fitted recovable filter mat of a chemically resistant material, preferably a polyester coating glass fibre material or polypropylene, with optimum surface. The collected sludge is discharged at intervals through the bottom of the tank unit, the unit cleaning liquid is recirculated continuously after filtration and added with fresh cleaning liquid. The apparatus is equipped with a double-acting suction system for vapours from the cleaning liquid and involves substantial advantages to the working environment.

Abstract: A filter includes a cylindrical filter element having a longitudinal axis, first and second end surfaces, and a plurality of longitudinal pleats. Each of the pleats has a pair of legs with first and second surfaces. The pleats are in a laid-over state in which the first surface of each leg is in intimate contact with the first surface of an adjoining leg and the second surface of each leg is in intimate contact with the second surface of an adjoining leg over substantially the entire height of each leg and over a continuous region extending for at least approximately 50% of the axial length of the filter element. An impervious end cap is connected to the first end surface of the filter element.

Abstract: This invention provides a composition, device and method for the removal of selected factors, such as cytokines or pharmaceuticals, from a substance such as whole blood or plasma. Advantageously, the invention provides for the treatment or prevention of septic shock syndrome or other conditions evidenced by the presence of cytokines in a patient by contacting the patient's whole blood with a composition comprising silica and a surface treatment material, such as heparin, but preferably human serum albumin (HSA). The treatment lowers the cytokine concentration of the blood. Pharmaceuticals can be removed from an individual's whole blood or plasma, such as for use in treating drug overdosage.

Abstract: Metal filter for a particulate trap which meets the requirements for low pressure drop, high collecting capacity and a long life. The metal filters have one or more layers of unwoven fabric (such as felt) formed of a metal fiber having one of the following alloy compositions A, B and C wherein composition A is made of Ni: 5-20% by weight, Cr: 10-40 by weight, Al: 1-15% by weight, the remainder being Fe and inevitable impurities; composition B is made of Cr: 10-40% by weight, Al: 1-15% by weight, the remainder being Ni and inevitable impurities; and composition C is made of Cr: 10-40% by weight, Al: 1-15% by weight, the remainder being Fe and inevitable components. The metal filter is highly resistant to corrosion and heat and can withstand repeated heatings for removal of the particulate.

Abstract: Process and apparatus for demineralizing water include a fibrous microporous body having interfiber spaces in communication with one another and a porosity at least equal to 50%, water supply elements for supplying water to be demineralized through the fibrous microporous body, a heating device adapted to heat the fibrous microporous body to a temperature of at least 60.degree. C., and elements adapted to collect the demineralized water.

Abstract: A filter material for filtering leucocytes from a fraction of or whole human blood, comprises a web having a thickness of at least about 1 millimeter and a bulk density of about 0.05 to 0.4 g/cm.sup.3. The web has a plurality of interlocked matrix fibers distributed in the web to form a matrix thereof with spaces between adjacent interstices of interlocked fibers. The matrix fibers are composed mainly of about 1 to 3 micron diameter glass fibers, i.e. at least 75% of the weight of the web being the glass fibers. A plurality of fibrillated particles of textile fiber material, having a surface area of between 5 and 100 square meters per gram are disposed within the spaces of the matrix. The weight ratio of the fibrillated particles to the matrix fibers is between about 1:99 and 40:60. A thermoplastic binder is disposed at least at cross-over portions of the matrix fibers, with the amount of the binder being about 0.1% to 10% by weight of the web.

Abstract: An expanded fiber composite structure and process for making an expanded fiber composite structure are provided. The expanded fiber composite structure is made up of a fiber mat held in partial compression by a monolithic plastic coating on the fibers, the structure having a plurality of interstitial voids which may optionally be filled with a polymeric interstitial material. The process includes impregnating a fiber mat with a plastic material, compressing the mat to impregnate the mat with the plastic, fully wetting each fiber and creating a substantially void-free fiber/plastic matrix, and reducing the compressive forces on the mat, allowing the fibers to rebound and expand the mat to a predetermined desired thickness, in the process creating the interstitial voids. The structure is then cooled such that the plastic material stiffens and itself retains the structure at the desired thickness.

Abstract: A fuel filter having a housing made of an electrically non-conductive material has a chamber disposed within the housing and the housing has an inlet and an outlet both in communication with the chamber. A filter media is disposed inside the chamber and is fluidly disposed between the inlet and the outlet for filtering non-polar substances such as fuel for internal combustion engines or the like. The filter media includes conductive fibers for preventing the buildup of or generation of electrostatic charges which would otherwise be generated by passage of fuel through standard paper filters such as those used almost universally in the automotive industry. These conductive fibers are preferably carbon fibers which consist of approximately two percent (2%) of the entire filter media.

Abstract: A composite membrane comprises an inorganic support having interstices and porous inorganic films of sintered non-metallic particles carried by the support and bridging the interstices thereof. The support is preferably a woven metal mesh, with the films substantially coplanar with the support. The films may be formed by applying a suspenion of refractory particles in a polymer solution to bridge the interstices of the support, and heating the films to partly sinter the particles. Since the films are in compression at ambient temperature, any cracks that may be formed by damage to the composite membrane tend not to propagate.

Abstract: A deodorizing filter which is composed of a honeycomb structure of ceramic fibrous paper supporting cuprous oxide or both cuprous oxide and solid acid; and a method for manufacturing the deodorizing filter wherein the ceramic fibrous paper is soaked in the slurry of the mixture of reductant-added water solution with the cuprous oxide and binder or with the cuprous oxide, solid acid and binder and is dried; and then the ceremic fibrous paper is formed into the honeycomb-type filter; or the ceramic fibrous paper with the binder added is formed first into the honeycomb-type filter and then is soaked in the slurry of the mixture of reductant-added water solution with the cuprous oxide and binder or with the cuprous oxide, solid acid and binder and finally is dried to make the deodorizing filter.

Abstract: A depth filtration method employing a depth filter media sheet, a method of forming the depth filter media sheet and the structure of the depth filter media sheet are described wherein the depth filter media sheet is formed from a wet strength layer and a filter septum layer, the filter septum layer being substantially thicker than the wet strength layer and being formed as a matrix from at least one fiber selected to provide substantial loft and pore structure throughout the filter depth of the filter septum layer, the wet strength layer and the filter septum layer being arranged adjacent each other and preferably bonded together with a lateral surface of the filter septum layer being substantially totally exposed for receiving fluid to be filtered with the porous matrix of the filter septum layer being available to receive and capture particulate solids from the fluid, the filter septum layer also preferably including a second fiber or additional fibers selected in combination with the first fiber for defin

Abstract: A filter material for filtering leucocytes from a fraction of or whole human blood, comprises a textile web having a thickness of between about 2 millimeters to about 12 millimeters and a bulk density of about 0.05 to 0.4 g/cm.sup.3. The web has a plurality of interlocked textile fibers with average deniers between about 0.05 and 0.75 and average lengths between about 3 millimeters and 15 millimeters. The textile fibers are distributed in the web to form a matrix thereof with spaces between adjacent interstices of interlocked fibers. A plurality of fibrillated particles of textile fiber material, having a surface area of between 5 and 100 square meters per gram are disposed within the spaces of the matrix. The weight ratio of the fibrillated particles to the textile fibers is between about 1:99 and 40:60. A plurality of glass fibers, having an average diameter of between 0.1 and 5 microns and being about 2% to 85% of the web, also form part of the matrix.

Abstract: A filter for filtering a highly viscous material comprises a filter element including a glass fiber filter medium, preferably resin-bonded, having upstream and downstream sides and a polymeric mesh situated on at least one of the upstream and downstream sides of the filter medium, and preferably on both sides of the filer medium. A non-woven sheet, such as a cellulose paper sheet, may be disposed between the downstream side of the filter medium and the downstream polymeric mesh. The filter element is typically cylindrical and longitudinally pleated to maximize the filtration area in as small a volume as possible. Also provided is a method of filtering a highly viscous material, particularly magnetic coating mixes.

Abstract: Mechanically strong and thermally/chemically-resistant composite nanofiltration membranes, well adapted for the separation of low molecular weight compounds, comprise a porous inorganic support substrate, the pore diameters of which ranging from 3 to 10 nm, this inorganic support substrate having a polymer membrane which comprises an elastomeric polyphosphazene densely deposited on at least one of the face surfaces thereof, the structural porosity of such polyphosphazene membrane ranging from 0.2 to 2 nm.

Abstract: A membrane support usable for separative procedures is disclosed. The support is a mechanically solid composite carbon-carbon material of limited thickness in the passage direction Z of a flow to be treated, which composite has a porous texture appropriate for the membrane, with a fibrous substrate and a porous carbon-containing matrix. To increase the permeability and reduce the roughness of the outer surface of the support to be brought into contact with the membrane, the fibrous substrate is a carbon fibre mat of carbon fibre segments contained in a plane perpendicular to the Z axis and randomly oriented in that plane. Optionally a fraction of the support to be in contact with the membrane contains an inert fine powder dispersion making it possible to adjust the diameter of the pores of the outer face of the support. Also disclosed is a process for the production of this membrane support and its use as a membrane support and as a filtering element without the addition of a membrane.

Abstract: A porous mineral support such as a porous mineral oxide coated with an aminated polysaccharide polymer has cationic characteristics and is capable of reversibly fixing thereto biological macromolecules. This material is employed in the separation and purification of said biologic macromolecules.

Abstract: A deep bed filter with a layer thickness of at least 1 mm comprises a pleated, self supporting filter layer (7, 8) which contains a mixture of long fibered material and short fibered material, whereby the fibers comprise cellulose and/or artificial fibers and whereby the filter layer preferably contains diatomaceous earth and/or perlite.

Abstract: A composite membrane for microfiltration comprises a woven metal mesh support and films bridging the interstices comprising inorganic particles, e.g. zirconia, bonded together by 1-25% of an inorganic adhesive. Group IV metal e.g. Si or Zr phosphate adhesives are preferred. Low temperature film formation without sintering permits the use of non-refractory metal supports.

Abstract: A flexible fleece-like filter material is provided wherein in a matrix-like basic framework consisting of synthetic or natural fibres, ultra-finely fibrillated fibres and/or inert porous particles are incorporated as a filter medium, the filter medium forming, anchored in the matrix, chain structures provided with a cationic or anionic charge or possibly charged with other substances which influence the filtering properties or with immobilised cells and/or catalysts. A fleece is formed with a thickness of between 0.5 mm and 5 mm and preferably up to 2 mm, which is flexible and which can even be pleated. This filter material can be produced by a simple method without harming the environment.

Abstract: A filter material for filtering leucocytes from a fraction of or whole human blood, comprises a shape-sustaining laid textile web having a thickness of between about 2 millimeters to about 12 millimeters and a bulk density of about 0.05 to 0.4 g/cm.sup.3. The web has a plurality of interlocked, staple, textile fibers with average deniers between about 0.05 and 0.75 and average lengths between about 3 millimeters and 15 millimeters. The textile fibers are substantially uniformly distributed in the web so as to form a matrix of the textile fibers with spaces between adjacent interstices of interlocked fibers. A plurality of fibrillated particles of a polymeric material, e.g. a textile fiber material, having a surface area of between 5 and 60 square meters per gram are substantially disposed within the spaces of the matrix.

Abstract: A single-layer blood separation medium for separating erythrocytes from whole blood and made of a composite including glass microfibers, cellulose fibers, and synthetic textile fibers, having enhanced tensile strength and lower absorptive capacity compared to binderless glass microfiber sheet. The mean bulk density of the glass microfiber component is less than 0.1 g/cm.sup.3, and is typicaly about 0.05 g/cm.sup.3.

Abstract: A filter aid material and a method for using same in a filtration system for reclaiming and maintaining coolant oil used in aluminum rolling or working processes are disclosed. The filter aid is a fibrous material which is permeated with an acid material and may be provided in either particulate form as a body feed or as a compressed filter pad. As contamined oil flows through the filter aid, the acid acts chemically to remove aluminum fines and oxides as well as the aluminum portion of contaminating soap in the coolant oil. Use of the filter aid with acid greatly reduces the amount of conventional filter aid previously used and produces a relatively small amount of residual filter aid which can be disposed of by incineration.

Abstract: A ceramic filter used for filtering molten metal, particularly molten aluminum, made by sintering the composition comprising 90 parts by weight of electrofused alumina for an aggregate and 5 to 15 parts by weight of an inorganic binder. The inorganic binder comprises 5 to 15 wt % of B.sub.2 O.sub.3, 15 to 50 wt % of MgO, 3 to 10 wt % of SiO.sub.2 and the remainder Al.sub.2 O.sub.3.

Abstract: A molecular sieve material is combined with a porous carrier material. The pores of the molecular sieve material are impermeable to molecules or organisms having a size equal to or greater than that of the water molecule either because the molecular sieve material is selected so as to have pores which are smaller than such molecule or because the pores of the molecular sieve material are closed by a film. The pores of the molecular sieve material thus remain unoccupied and are able to exert an attractive force on molecules or organisms which are to be captured. The pores of the carrier material are designed to accept molecules or organisms having a size equal to or greater than that of the water molecule so that, when such molecules or organisms are attracted by the molecular sieve material, they can be trapped in the carrier material.

Abstract: The present invention relates to ceramic foam filters having a gasket material chemically and mechanically bonded thereto. The filters have particular utility in the filtration of molten metal, especially aluminum. The filters are formed by immersing the porous filter body, preferably in a fired condition, in a gasketing medium consisting of a concentration of ceramic fibers, one or more binders, and the balance a vehicle such as water and applying a vacuum through the porous filter to draw the gasketing medium into contact with the portions of the filter body to be gasketed.

Abstract: A filtrating apparatus is disclosed in which a filter unit and a washing unit for effecting a fluid washing are unified into one system. A plurality of filter elements of main filters provided in the filter unit are made of sintered material containing metallic fiber. A nominal filtration rating of the filter elements is greater than 0.3 .mu.m but smaller than 2 .mu.m. Accordingly, it is possible to ensure the smooth filtration of beer funguses without any necessity of interchanging filter elements. It is therefore possible to reduce a running cost and filtration cost and to save a space for the apparatus.

Abstract: Blood separation filter assemblies and methods are provided to quickly and completely separate plasma or serum from whole blood without the need of centrifugation. The filter assemblies and methods have filter materials of a predetermined thickness which are maintained under positive pressure during use. The filter materials have at least one layer of glass fibers having an average fiber diameter ranging from 0.2 .mu.m to 7.0 .mu.m and which are compressed at least 25% in thickness.

Abstract: A method for separating plasma from red blood cells and a device utilizing the method in which a low-pressure filter is interposed in a pathway between an inlet port and a reaction area. The sole driving force for the movement of plasma from the filter to the reaction area is capillary force provided by a tubular capillary. The filter is selected from glass microfiber filters of specified characteristics, which can operate in the absence of agglutinins, and filters capable of separating agglutinated red cells from plasma, which require the use of an agglutinin.

Abstract: In a process for the manufacture of a filter for liquid or gaseous media, especially for exhaust gases of combustions engines, the filter is formed from one or several filter plates out of a mesh, network, reticulation or fabric of metal wires. The filter body of a plurality of layers or plies of wires is brought between the electrodes of a resistance welding unit and subsequently a resistance welding is performed for partial connection of the wires to one another by spot welding.

Abstract: Preparation of binary membrane ultrafiltration (UF) toplayers (Al.sub.2 O.sub.3 -CeO.sub.2 and Alhd 2O.sub.3 -TiO.sub.2) to make chemically stable UF membranes and/or or catalytically active membranes. Two stable sols are prepared and mixed under controlled conditions and a top layer is prepared on a support under controlled conditions.

Abstract: There is disclosed a fluid filtration element having a porous core cylinder, a sectionally thick filtration cylinder fitted around the core cylinder, and end plates secured to the end surfaces of filtration cylinder. Highly densified portions are formed at the filtration cylinder ends to which the end plates are press-fitted, thereby hindering the fluid permeation. Sectionally thin protrusions erected on the end plate surfaces are cut into the highly densified portions.

Abstract: Filter pads, which are made inherently stable by binders and by removal of the binders can be converted in packings to be maintained under substantially constant surface pressure between rigid filter brackets, are produced first as molded bodies from a suspension of filter aids in liquid by depositing granular, fibrous, or fiber-containing filter aids or mixtures of those filter aids in a casting mold, there being used high rates of flow while avoiding turbulences, and adding binders to the suspension so that the molded body can be stabilized by activation of the binder while drying. It is possible in this process also to manufacture multi-layered filter pads, it having been surprisingly found in those multi-layered filter pads that the layer assembly is kept intact during the filtration even in the filter packing that no longer contains binders.

Abstract: A recirculating fiber filter (1) and method is provided for removing particulates from moving fluid streams. High aspect ratio fibers (2) are used which readily nest with each other to form the high voidage fiber filter bed. In the method, fibers are continuously removed from the bottom of the bed regenerated to remove particulates and recycled back to the top of the bed and distributed thereon. Dirty fluid is passed from the top to the bottom of the filter. Dendrites of the particulate impurity appear to buildup in a thin section (A) at the top of the filter and provide the primary mechanism for further particulate entrapment. Recirculation of fibers offers a continuously fresh volume of fibers at the top for capture of particulates.

Abstract: A heat fumigation apparatus for transpiring a solution of a chemical agent dissolved in a solvent by heating which comprises a container having the solution therein, a wick a part of which is immersed in the solution and a heater for heating the upper portion of the wick thereby transpiring the solution drawn up the wick. The wick is composed of an inorganic powder and/or an organic powder, a binding agent and at least one antioxidant which is substantially non-evaporative at a heating temperature.

Abstract: A unique blood filter matrix material is provided which is able to effectively separate whole blood into cellular and noncellular constituents, especially when the whole blood volume is 0.5 milliliters or less. The filter matrix presents an overall negative surface electrical charge to the whole blood and utilizes a mechanism of action to rapidly separate cells from plasma or serum.

Abstract: The invention relates to a support intended to receive a mineral membrane for separation procedures, and processes for the production thereof. The support is formed by a carbon-carbon composite material of small thickness, which is mechanically strong and which is of a porous texture suited to the mineral membrane. It is produced by adjusting the porous texture of a carbon-carbon material.

Abstract: A filter media (10) of the type supported across a fluid flow passage for collecting particulate out of the fluid and subsequently being moved out of the flow passage after becoming congested with particulate. The filter media (10) includes a top layer (12), a middle layer (14), and a bottom layer (16). The middle layer (14) comprises a support web (18) formed by entwined cotton fibers (20), and a mesh (22) supported by the web (18) formed by entwined glass microfibers (24). The middle layer (14) forms a plurality of minute pore passages between adjacent glass microfibers (24) and cotton fibers (20). The top layer (12) is a nonwoven wet laid polyester material for preventing adherence of the fiber media (10) to the edges of the fluid flow passage. The bottom layer (16) is a nonwoven spun bonded polyester material highly resistant to tear for supporting the filter media (10) while it is moved out of the flow passage.

Abstract: A self-supporting composite filter for ultra filtration that can be backwashed has a central porous body which supports a thin diaphragm of fine porosity applied to the outer surface of the body. The body is porous, being formed by coarse grains and a binder. The diaphragm is thin in comparison to the filter body and is formed from a mix of fine grains, fibers and binder whose percentage composition, by volume, is in the ratio 60 to 40:40 to 20:30 to 10. The fibers are thin, 0.3 to 30 microns, and long, with a length at least 10 times their width to provide a microelasticity in the diaphragm. The absolute thickness of the diaphragm is 0.2 to 2 millimeters which is 5 to 75 times smaller than that of the support body. The ratio of the specific permeabilities of the support body to that of the diaphragm, for fluids in the laminar flow range, is between 2:1 and 100:1.

Abstract: A unitary injection molded filter is disclosed which includes a rigid frame of resin material to provide a rigid shape to the filter, and at least one screen of non-woven sheet resin material suspended on the frame and having formed therethrough a plurality of holes extending between the opposed side surfaces of the screen so as to form fluid passages therethrough. Each screen is integrally molded simultaneously with the frame.

Abstract: A cell separator which can separate cells, especially lymphocytes, with high selectivity and high efficiency without changing the cell population ratio of the cells. The cell separator comprises fibrous material containing fibers including hydroxyl apatite.

Abstract: A filter for separating solid particles, whose diameters are generally smaller than 5 .mu.m, from flowing gases or liquids. A covering layer with columnar and/or platelet-shaped oxides is formed on a body consisting of porous steel foil at least in and around the pores.

Abstract: A device for separating plasma or serum from whole blood and analyzing the same, wherein the device includes a layer of glass fibers with an average diameter of from 0.2 to 5 microns and having a density of from 0.1 to 0.5 g./cm.sup.3 and an adsorption volume at least twice that of the plasma or serum to be separated and, preferably, more than 3.3 times the volume.

Abstract: Hydrophilic glass fibers which have bonded to their surfaces a layer of silane molecules of the formula ##STR1## are useful for the separation of plasma from blood for haemostasiological testing. In the formula: the molecule is bonded at its end oxygen to a surface of a glass fibre; R.sub.1 is C.sub.2 -C.sub.6 alkylene; X is OH, C.sub.1 -C.sub.6 alkoxy, having n carbon atoms and up to (n-1) OH groups in which n is 1-6, or an amino acid or peptide residue; and each of R'.sub.3 and R".sub.3 is C.sub.1 -C.sub.6 alkyl, an oxygen bridge to the silicon atom of another silane molecule or an oxygen bridge to the glass surface. The fibres have an average diameter of from 0.2 to 5 microns and a density of 0.1 to 0.5 g/cm.sup.3.

Abstract: The invention relates to a process for producing a tubular glass membrane with wall thicknesses between 5 and 30 microns and reproducible pore sizes between 11 A and 50 A. Alkali borosilicate glass is drawn into discrete hollow tubes and immediately cooled. The tubes are thermally treated to effect a phase separation into a coherent silicon dioxide phase and a boron oxide phase rich in alkali borate. The boron oxide phase is leached out with mineral acid. The tubes can be subsequently treated to give enlarged or reduced pores, asymmetric pores and coated surfaces.

Abstract: A method for filtering liquid or gaseous materials where the filtration is conducted with a porous filter media prepared from an aqueous wet-laid, lofted fiber-reinforced composite sheet, the composite sheet comprising a heat fusible polymer, reinforcing fibers and a binder. The random fiber composite sheet can be selectively lofted or recompressed to form filter media having variable porosity. Also, a membrane support means prepared by applying or treating the fiber-reinforced composite sheet with a discriminating membrane layer.

Abstract: A filter element has a generally ring-like structure which basically comprises a plurality of generally radial sections circumferentially arranged to define a central space. Each radial section has a plurality of circumferentially zigzag pleats formed from a ribbon of a filtering sheet material. The radial sections are circumferentially connected such that radially inwardly open generally radial spaces and radially outwardly open generally radial spaces are defined. The radially inwardly open radial spaces are closed at the axially opposite ends by end walls. Fluid to be filtrated can enter the radially outwardly open radial spaces and then passes through the zigzag pleats into the radially inwardly open radial spaces and thus into the central space. The ring-like structure has many modifications.