Abstract: A filter element (202, 250) includes pleated filter media (26) having a plurality of pleats (28) in a closed annular loop having an outer perimeter (30) defined by a plurality of outer pleat tips (32), an inner perimeter (34) defined by a plurality of inner pleat tips (36), the loop having a hollow interior (38) extending along an axis (40), wherein fluid to be filtered flows laterally through the filter media and flows axially in the hollow interior (38). The filter element has an axial flow passage (56a) along the axis (40) and circumscribing the hollow interior (38) and has a flow perimeter (218) greater than the inner perimeter (34) of the filter element defined by the inner pleat tips (36), and in the preferred embodiment substantially the same as the outer perimeter (30) defined by the outer pleat tips (32), to provide axial flow (58) through the hollow interior (38) and additional axial flow (59 and 59a) through the axial ends (68) of the pleats.

Abstract: A filter element (22) includes pleated filter media (26) having a plurality of pleats (28) in a closed annular loop having an outer perimeter (30) defined by a plurality of outer pleat tips (32), and an inner perimeter (34) defined by a plurality of inner pleat tips (36), the closed annular loop having a hollow interior (38) extending along an axis (40), wherein fluid to be filtered flows laterally through the filter media and flows axially (58) in the hollow interior (38). The filter element (22) has an axial flow passage (56) along the axis (40) and circumscribing the hollow interior (38) and has a flow perimeter (60) greater than the inner perimeter (34) of the filter element defined by the inner pleat tips (36). An end cap (66) of resilient compressible material at the axial end (62) of the filter element bears radially between and is radially compressed between an outer liner (102) and a flow tube (90) at the enlarged flow passage (56).

Abstract: A filter element is adapted to be located in a gas stream. The filter element comprises a substrate having a structure selected from the group consisting of scrimed needled felt, scrimless needled felt, woven fabric and mesh. The substrate comprises at least two different materials. A first one of the materials has a first melting temperature. A second one of the materials has a second melting temperature lower than the first melting temperature. An expanded polytetrafluoroethylene filtering membrane is adapted to be located upstream relative to the substrate in the gas stream and supported by the substrate. The substrate is attached to the filtering membrane by the second material of the substrate melted to engage the membrane and fix the membrane to the substrate.

Abstract: A fluid filter includes a first batting of high loft, non-woven, fibrous fluid-permeable material with a plurality of openings formed through the thickness thereof across the length and width of the batting. A second layer of high loft, non-woven, fluid-permeable fibrous batting is attached to the first layer and extends across the entire length and width of the first layer. Preferably, the first and second layers are adhered together to form a single integral fluid filter. In the preferred form of the invention, the openings in the first batting have side walls which are perpendicular to the upper surface of the batting, such that fluid flow impacts on the upper surface of the batting, rather than directly impacting on the side walls.

Abstract: A filter element, in particular for purifying the intake air of an internal combustion engine, constituted by a non-woven fabric or paper folded in the manner of a concertina and secured as a flat plate in a frame (10). In order to increase the stability of this filter medium (11), strut segments (19, 20) are disposed on the frame, which engage in folds in the plate and are bonded thereto.

Abstract: A filter in a printing machine traps contaminants from a stream of air passing therethrough. The filter includes a support member defining an aperture therethrough for the passage of the stream of air. The support member has a cross section in a plane perpendicular to the flow of the stream of air. The cross section has an oblong shape and includes a longitudinal axis and a transverse axis. The filter further includes an air permeable member supported by the support member. The air permeable member defines a opening therein for receiving the stream of air. The filter further includes a reinforcement connected to the air permeable member. The reinforcement extends along the air permeable member in the direction of the stream of air. The reinforcement is positioned with respect to the support member so as to shape the air permeable member so that the opening may be sufficiently large to efficiently receive the stream of air.

Abstract: A cartridge filter is adapted for mounting on a tube sheet in a baghouse filter system and can be configured for removal from either the top or the bottom of the tube sheet. The cartridge filter includes a filter tube with proximate and distal ends and a filter tube passage extending therebetween. The filter tube includes a media element and mounts a tube mounting assembly on its proximate end and a cap on its distal end. The tube mounting assembly includes a boot for attachment to either the tube sheet in a top removal configuration or to a bagcup mounted on the tube sheet in a bottom removal configuration. The tube mounting assembly also includes a connector which is molded onto the boot and which pots the filter tube proximate end.

Abstract: A filter includes a center layer of carbon cloth interposed between two layers of filter material whose edges are welded together to provide not only a filter edge substantially free of carbon particles, but also an effective barrier to the migration of carbon particles from the filter's interior to its exterior. A filter pouch, encapsulating the carbon filter, includes a layered structure welded together proximate its edges. The filter pouch is also suitable for use with a desiccant filter.

Abstract: Porous materials suitable for a variety of uses including waterproof/breathable fabrics, air filters, liquid filters, liquid/liquid separation membranes, vascular grafts, mechanical seals, etc. which comprises an intimate combination of about 50 to 99.9 wt % polytetrafluoroethylene polymer and about 0.1 to 50 wt % of a fluorinated organic polymer which is liquid under ambient conditions, such as the perfluoroether fluids, wherein the material has a microstructure characterized by nodes interconnected by fibrils.

Abstract: A replaceable air filter for filtering inlet air to an engine has a heavy-duty housing which protects the filter element from heat and damage due to improper handling. The durable housing further provides additional surfaces for mounting the air filter to a combustion engine. The filter element inside the housing is permanently sealed to the housing, thereby reducing the risk of unfiltered air from bypassing the filter element to enter the air intake tube. Because the filter element is permanently attached to the housing, the entire air filter must be replaced during routine maintenance, thereby reducing the risk of loose dirt from spent filters being drawn into the engine. A snout member is injection molded to have an air outlet which may be sized for connection with either a flexible or rigid air intake tube.

Abstract: An air filter, especially for cleaning combustion air for internal combustion engines. The air filter includes a substantially cylindrical housing having a raw inlet and a pure air outlet. A pure air outlet is fitted substantially concentrically on the face of a cylindrical housing. The raw air inlet is fitted on the surface of the housing jacket, and an essentially menthol-free filter element is secured in the housing. The housing aperture is fitted with adaptive systems having an integrated dirt extractor.

Abstract: An open-pore polyurethane foam support body (20) is impregnated in a single step with a solution of a thermoplastic adhesive dissolved in a solvent that is also a foam expander, or in two sequential steps first with a foam expanding solution and then, after the foam has expanded, with a solution of a thermoplastic adhesive, to form an adhesive layer (40) on the surfaces (25) within the pores (22) and passages (24) of the foam body (20). Sorbent particles (30) of activated carbon are introduced into the expanded pores until the expanded foam is packed to the desired density of carbon particle loading. The impregnated and loaded foam is then air dried at room temperature to evaporate the foam expanding solution until the foam body contracts to substantially its original volume.

Abstract: Porous materials suitable for a variety of uses including waterproof/breathable fabrics, air filters, liquid filters, liquid/liquid separation membranes, vascular grafts, mechanical seals, etc. which comprises an intimate combination of about 50 to 99.9 wt % polytetrafluoroethylene polymer and about 0.1 to 50 wt % of a fluorinated organic polymer which is liquid ambient conditions, such as the perfluoroether fluids, in the material has a microstructure characterized by nodes connected by fibrils.

Abstract: An evaporative humidifier includes a base having a portion defining a reservoir for holding a quantity of water. A housing is mounted on the base over the reservoir, the housing having an air inlet and an air outlet. A cylindrically shaped wick filter with a permeable support is seated in the reservoir and extends up into the housing. The cylindrically shaped wick with permeable support filter has an open top end and a sidewall. A color change indicator strip is provided on the inner portion of the sidewall. The color change indicator strip provides a signal when the filter requires changing due to the extent of use and immersion of the filter in water. A fan is mounted inside the housing for drawing air into the housing through the air inlet, then into the center of the cylindrically shaped wick filter through the open top end, then out through the sidewall of the cylindrically shaped wick filter with a permeable support and then out of the housing through the air outlet.

Abstract: An air cleaner including a housing and a filter element. The housing has an air inlet and an air outlet, and includes a body having an open end, and a removable end cap adapted to close the open end of the body. The filter element is positioned within the housing between the air inlet and the air outlet. The filter element is securely attached to the end cap to be removable from the housing when the end cap is removed from the body. The permanent attachment of the filter element to the housing end cap in accordance results in a more reliable filter because the proper sized filter element is always present and securely positioned in the housing when the housing is closed.

Abstract: An apertured film extruded from a crystalline, thermoplastic, extrudable fluoroplastic material. The film includes spaced-apart strand segments defining apertures therebetween and has at least 10 strand segments per inch. The film has a thickness of 2-12 mils and a Frazier air permeability number in the range of 200-2,000. The invention includes a process for preparing an apertured thermoplastic film by a single-sided embossing method. The process includes the steps of extruding in the machine direction, a film of a molten, crystalline, thermoplastic, extrudable, fluoroplastic material. The molten extruded film is passed in the machine direction through the nip of two metal rollers. One of the rollers has a substantially smooth surface, having a convex configuration as viewed from a direction substantially parallel to the axis of the roll, such that the diameter in the center of the roll is in the range of 8-12 mils greater than the diameter at the ends of the roller for a 40 inch roller.

Abstract: A desiccant canister comprised of a generally cylindrical body portion, first and second end portions, and at least one gas permeable disk-shaped member, wherein the body portion is generally impermeable to liquids and gases, wherein at least one of the said end portions is perforated, and wherein the disk-shaped member is secured to the end portion of the canister containing perforations.

Abstract: A pleated filter medium arrangement including a sheet of pleated porous filtering media nestingly engaged between adjacent pleats by a pleated sheet of thermobondable plastic screening with preselected facing opposite portions of the screening being heat bonded together.

Abstract: A container for particulate desiccant includes a cup and a cap. The cup includes spaced inner and outer wall portions connected by a transverse web portion to define a chamber having an opening for receiving the desiccant. The chamber side of the transverse web includes peripheral and central flanges, or energy directors, to which a first ply of permeable lining material is ultrasonically bonded. The cap is designed for receipt in the chamber to cover the opening. In addition, the cap has a hole for receiving the inner wall portion of the cup, and the chamber side of the cap includes peripheral and central flanges, or energy directors, to which a second ply of permeable lining material is ultrasonically bonded. The inner wall portion includes a beveled inner end surface which tapers radially inwardly in a direction toward the transverse web portion to facilitate insertion of a canister pipe into the inner wall portion.

Abstract: An efficient, light-weight airbag inflation filter includes a gas-permeable, substantially rigid support tube having a plurality of uniform perforations therethrough. A filtering element formed from a continuous inorganic ceramic yarn or roving is helically cross-wound around the support tube to form one or more layers covering the perforations of the support tube. A wire screen, having openings therethrough smaller than the perforations in the support tube, is disposed between the filtering element and the support tube to act as a gas diffusion layer for the gases passing through the inflation filter.

Abstract: A filter cartridge for use in a filter system, in which the cartridge has no structural metal or plastic parts and is adapted for environmentally acceptable disposal. A pleated paper filter media is formed into a cylinder, and potted end caps at the axial ends of the cylinder hold the shape of the filter. Sealing gaskets are associated with the end caps. At least one side has a radial seal formed at the outer periphery of the filter cartridge to protect the associated end cap from higher a pressure region found at the outer periphery. The other axial end can have a similar radial filter in some applications, or in other applications, where flow at that end of the filter is not desired, can utilize an axial seal specially configured to protect the associated end cap from higher pressure at the outer periphery. Maintenance of lower pressure at the respective end caps places any axial loads on the filter in tension, and thereby prevents the application of axial crushing loads on the filter cartridge.

Abstract: A portable air cleaner designed to remove fine particles and unwanted gases from a room to provide for a healthier and cleaner environment. The portable air cleaner includes a high air volume circulating design and operates quietly and efficiently. The portable air cleaner is designed to minimize the unsettling of particles which have settled out on the floor about the base of the air cleaner so as not to aggravate the particle concentration within the room environment. The portable air cleaner includes a particle filter designed to have ultra high efficiencies with respect to particle removal. Disposed coterminous to the particle filter to remove unwanted gases from the filter air to provide for improved cleaner and healthier environment.

Abstract: Air filtration media is formed by collecting a layer of fine diameter glass fibers directly on a foraminous, reinforcing, backing layer and subsequently collecting a layer of relatively coarse diameter glass fibers directly on the layer of fine diameter glass fibers. A bonding agent carried by the glass fibers is then cured to bond the glass fibers within each layer together at their points of intersection, to bond the layers of fine and coarse glass fibers together and to bond the layer of fine diameter fibers to the backing layer. This method of forming the composite air filtration media permits the particle efficiency and the dirt loading capacity of the composite air filtration media to be adjusted during the production of the media by adjusting the diameters of the glass fibers in one or both of the layers and/or by adjusting the density of one or both of the layers.

Abstract: The present invention is an improved catalytic filter material for use in removing contaminants such as NO.sub.x from a fluid stream. The filter of the present invention employs composite fibers of expanded polytetrafluoroethylene (PTFE) filled with catalytic particles. The composite fibers are chopped into staple fibers and made into a felt material. Preferably, the felt material is then laminated on at least one side with a protective microporous membrane. The combined filter removes both macro-particles, such as dust, from the filter stream before the dust can clog active catalytic sites and effectively catalytically coverts undesirable contaminants in the fluid stream to acceptable end products.

Abstract: An adsorbent assembly is provided for removing gaseous contaminants from an enclosure having an adhesive layer, an adsorbent layer and a filtering layer. An exterior mounted assembly is also provided having an outer layer containing a metal or metallized material that provides an electromagnetic shield to the enclosure.

Abstract: A fiber glass air filtration media includes a blanket of glass fibers with about 25% to 35% by weight of the glass fibers being fine glass fibers having an average diameter of less than 3.5 microns and about 65% to 75% by weight of the glass fibers being coarse glass fibers having an average diameter of more than 3.5 microns. The fine and coarse glass fibers are randomly intermingled throughout the blanket. The blanket is formed by producing the fine glass fibers on a first set of fiber generators and the coarse glass fibers on a second set of fiber generators. The fiber generators are laterally aligned across the width of and direct gaseous streams of the glass fibers at a moving collection surface where the blanket is formed. The fiber generators of the first set alternate with the fiber generators of the second set and the glass fibers produced by the two sets of fiber generators are mixed together before being deposited on the collection surface.

Abstract: The present invention is an improved sorbent filter for use in both particulate filtration and absorption of gaseous contaminants in a variety of applications, such as for filtration in a computer disk drive. The filter of the present invention provides previously unavailable levels of combined particulate filtration and contaminant sorption while being capable of ready reconditioning (such as through washing with D.I. water).

Abstract: The filter element (10) includes a filter material layer (12) being held and supported by a support material layer (14). The support material layer (14) can be folded in zig-zag manner and has bending regions (16, 17) with folding portions (18) therebetween. The support material layer (14) has the region of its folding portions (18) provided with deformations (20) projecting from the planes of the folding portions (18). The filter material layer (12) is supported by the support material layer (14) through the boundary edges of the deformations (20).

Abstract: A compact sorbent filter for selectively sorbing contaminants and method of removing contamination from an enclosure with a filter is disclosed. The filter comprises a sorbent core including contaminant adsorbing material therein, an outer protective cover wrapped around the inner sorbent core so as to completely contain the sorbent core, with the exposed end(s) of the core being capped so as to encapsulate the sorbent core present within the filter while not limiting the amount of material contained therein. A sorbing filter is placed within an enclosure to remove gaseous contamination therein. The filter is particularly suitable for use in a computer disk drive or similar enclosure where out-gassing contamination may be a problem.

Abstract: An ostomy filter for colostomy and ileostomy bags is gas-permeable to allow venting, and liquid-impermeable to prevent leakage. It includes a hydrogen sulphide adsorbent to remove smells. The filter comprises 9 to 50% by weight of particles of unsintered granular polytetrafluoroethylene (PTFE), 30 to 82% by weight of particles of comminuted sintered expanded porous PTFE, and 9 to 30% by weight of particulate water-insoluble H.sub.2 S adsorbent. The particles are fused together by baking at elevated temperature to form a gas-permeable liquid-impermeable network. The comminuted sintered expanded porous PTFE is preferably formed by comminuting uniaxially expanded PTFE fibre.

Abstract: An air filter element includes a media pack formed by inner and outer tubular liners and by a sleeve of filter media located between the liners. Moldable potting compound (e.g., Plastisol) is located at each end of the media pack to hold the liners and the filter media in assembled relation. A separately formed sealing gasket molded of Nitrile rubber is joined to one end of the media pack by a ring of the Plastisol, which encapsulates part of the sealing gasket. When the filter element is installed in a housing, the sealing gasket resiliently engages a sleeve and establishes a radial seal between the filter element and the sleeve. The end of the media pack opposite the sealing gasket is closed by a cap molded of the Plastisol and reinforced by a plate made of metal or stiff plastic.

Abstract: A microfibrous sorbent article is provided. The microfibrous sorbent article comprises an elongate boom having a substantially oval cross-section. The boom is formed of multiple adjacent microfibers layers, the layers being bonded to each other by entanglement of fibers between adjacent layers. The boom further contains ion exchange resin, selectively absorbent particulate material, catalytic agent or selectively reactive particulate material.

Abstract: A filter for use in a concrete press mould, the filter comprising a fabric being knit or woven at least in part from heat meltable yarns and having a fabric density which permits the passage of water therethrough but prohibits the passage of particulate material, the filter being bounded around its periphery with at least one continuous imperforate band integrally formed with the fabric by fusion of said heat meltable yarns.

Abstract: An improved air diffusion panel, and method of construction and use, is provided which is particularly suitable for use in clean and ultra-clean environments, such as clean rooms and mini-environments facilities. The preferred diffusion panel of the present invention includes a diffusion membrane of a continuous mass of porous polytetrafluoroethylene bonded to one or more support screens of polymer mesh. The composite membrane and screens are mounted in a unique frame which eases the time and effort required for construction of the panels and which can be mounted to reduce vibration of the panel and leakage around its edges. This improved air diffusion panel also significantly filters small and sub-micron particles, resists chemical attack, and blocks liquid droplets.

Abstract: A self-supporting filter of adsorbent particles is provided by agglomerating the adsorbent particles with a thermoplastic binder and forming a self-supporting filter with a low pressure drop and high efficiency suitable for use as an automotive cabin filter.

Abstract: A generally flat air filtering device for an optical disk drive is disclosed. As air is sucked into the disk drive via an inlet of a filter, a filter mat included in the filter removes dust and other impurities from the air. The purified air comes out of the outlet of a tube and then enters and cools an optical disk unit. The filter mat has a generally V-shaped section and, therefore, has a filtering area great enough to enhance efficient dust collection as well as the service life of the filter. To isolate the purified air from surrounding dust-containing air, an endless projection or rail is provided on the tube to bite into the filter mat which is flexible.

Abstract: A unitary filter medium that is composed of a sheet of porous substrate that has bonded to its upstream surface a plurality of separate spaced apart islands of flock fibers, the fibers of adjacent islands at least partially overlapping. The flock fibers are bonded by calotte shaped adhesive structures to the substrate so as to form porcupine-like arrays.

Abstract: A filter composite is made of a porous polytetrafluoroethylene (PTFE) and a fabric. The PTFE and fabric are bonded by an adhesive. The adhesive is prevented from penetrating the fabric by employing a coating of an oil and water-repellent material to the surface of the fabric adjacent the adhesive.

Abstract: A process for producing hermetically sealed filters is disclosed. The process includes the steps of providing thermoplastic base and top filter parts and a section of filtration media, sandwiching the media between sections of the base and top filter parts under a compressive force, applying a rapidly repetitive force to at least one of the filter parts to cause movement between the parts and frictional welding of the parts, maintaining the compressive force after frictional welding to allow the melted portion of the parts to solidify and thereby form a fluid seal at the junction of the filter parts and at the junctions of the filtration media and each of the base and top filter parts. In one embodiment, the junction between the filter parts is the periphery of an automatic transmission filter, and the junction is hermetically sealed. A hermetically sealed automatic transmission filter is also disclosed.

Abstract: The invention includes a filter element (10) having a pair of end caps (12) with pleated, corrugated filter media (14) spanning therebetween. The filter media (14) is sealed or potted into the end caps (12) with a potting material ( b 16). To ensure substantially uniform penetration of the plates of the media (14) by the potting material (16), the edges of the media (14) are configued to eliminate "linear check valve" action between pleats. Several edge patterns can be used to minimize the formation of linear check valves, including a saw tooth pattern; sine wave pattern; vertical edge corrugations; flat edge regions; and saw kerfs in the edges of the media.

Abstract: A cylindrical screen construction for a filter and a method of producing the screen. A sheet of metal screen containing a multiplicity of holes is rolled into cylindrical form and the longitudinal edges of the sheet are joined by a thermoplastic connecting strip. The strip is generally H-shaped in cross section having a pair of opposed longitudinal grooves that receive the respective edges of the sheet. Heat and pressure are applied to the strip causing the thermoplastic material to fuse and penetrate the holes along the side edges of the screen to provide a smooth surfaced mechanically interlocked joint between the edges.

Abstract: A filter or filter assembly in which at least the frame work is made of magnetic material which holds the filter or filter assembly in place without the need of hardware and which is easily removed for cleaning or changing. The applications or numerous such as vehicle vents, swimming pools, spas, radiator covers, or any opening which needs to be filtered which has a metal frame work or opening.

Abstract: A filter element comprises at least two pleated filtering mediums and at least one roughly flat filtering medium interposed between the pleated filtering mediums. Each pleated filtering medium has an end constituted by edges of triangular bottom sections and the other end constituted by edges of triangular top sections. The triangular bottom sections of one pleated filtering medium is bonded to the flat filtering medium only at and near the edges of the bottom sections. The triangular top sections of the other pleated filtering medium is bonded to the roughly flat filtering medium only at and near the edges of the top sections. Spacers are provided between the top sections and the flat filtering medium and between the bottom sections and the roughly flat filtering medium. Such spacers may be constituted by alternate small ridges and grooves formed in the roughly flat filtering medium.

Abstract: An air filter for attaching to a top and/or bottom surface of a fan blade. The air filter is constructed from an elongated strip of porous material capable of having air pass therethrough while trapping airborne particles borne by the air. Also, the elongated strip has opposed exposed surfaces and a peripheral edge extending therearound and preferably, an adhesive strip having opposite surfaces and an adhesive substance on each of the opposite surfaces is attached to one side edge of the elongated strip. The other opposed surface of the adhesive strip is preferably attached to a top and/or bottom surface of a fan blade. Thus, the filter strip sweeps and filters air moving across the one surface of the fan blade as the fan blade rotates.

Abstract: An air filter including a generally tubular filter element having an open air outlet end and a closed end is provided with a molded ring-like end cap of a soft elastomer material. A tubular air outlet member is mounted in the open end of the filter element with the end cap having a radially inwardly facing surface constructed so as to be compressed to sealingly engage the outlet member to block flow of contaminated air therebetween. A housing having an air inlet surrounds the filter element to provide an air distribution chamber for incoming contaminated air.

Abstract: A filter having a structural framework (45) formed integral with and surrounding an active filtering area, and a process for manufacturing the filter are disclosed. The process includes (a) masking selected areas (40) on a sheet (30) of filter media, which areas will serve as the active filtering areas in the end filter product; (b) applying to the remaining exposed areas of the media a liquid-phase filler material; (c) forcing the material to fully penetrate and completely saturate the exposed media areas; (d) and curing the filler-saturated media areas whereby the filler material solidifies within the fiber structure of the media making that portion of the media sheet impervious to any air flow therethrough. The sealed media area (45) provides a structurally integral framework which is continuous with the active filtering media area (40) of the filter. The filter may then be secured along its integral framework area (45) to a suitable mounting substrate surface.

Abstract: A non-clogging and wear-reducing screen assembly for a vibrating screening machine including a substantially rigid plate having upper and lower sides and having first and second pairs of opposite edges, attachment members formed integrally with a plate on a first pair of opposite edges for attachment to a vibrating screening machine, a plurality of spaced openings throughout the substantially rigid plate and extending in both directions between the first and second pairs of the opposite edges, borders on the plate surrounding the openings, a supporting screen on the upper side of the plate, first and second superimposed contiguous abutting screens overlying the supporting screen, and adhesive firmly securing the supporting screen and the first and second screens to the borders of the openings.

Abstract: In a deodorizing gas filter for ostomy bags (22), consisting of a sheet (10) of deodorizing filter material, for example a porous foamed plastic with particles of active carbon, and having a central inlet opening (12), a gas-tight connecting layer (14) to the bag on one side of the filter sheet, and a gas-tight covering layer (24) on the other side of the filter sheet, the covering layer consists of elastic film material, or is provided with a layer of elastic material at least in that part covering the central opening and an immediately surrounding zone thereof.

Abstract: An improved method for attaching a hydrophobic vent directly to a urinary drainage container without requiring special supplemental donut-shaped sandwich structures for retaining the filter. The substantially improved fusion bond is obtained by a special seal structure formed by a die having two protruding fusion ribs separated by a relief groove. The seal structure formed by such a die permits direct sealing of a silicone treated hydrophobic vent to a thermoplastic bag wall with a firm viable seal.

Abstract: Improved disposable nose and mouth filter masks are disclosed each of which is comprised of a sheet of a suitable air filtering material, sized and configurated for use in pairs to individually loosely cover the mouth and nostrils of the face of a wearer. A continuous peripheral adhesive strip is applied to peripheral edge areas of the filters with a removable backing strip being normally engaged on the inner exposed adhesive surface, the adhesive strips being applied in overlapping relation in the area between the nose and mouth of the user.