Abstract: A method of making an electret includes condensing vapor from the atmosphere of a controlled environment onto a dielectric article and then drying the article to remove the condensate. The dielectric article may be a nonconductive polymeric material, and the condensate may include a polar liquid. The method is particularly useful for forming an electret from a porous material such as a nonwoven fibrous web. The method can enable individual fibers in the web to exhibit at least quasi-permanent electrical charge.

Abstract: A filtering face mask that includes a mask body that is adapted to fit over the nose and mouth of a person and a harness that is attached to the mask body. The mask body comprises i) a first shaping layer that has been molded; ii) a second shaping layer that has been molded; iii) a filtration layer that is disposed between the first and second shaping layers; iv) a first adhesive layer that adheres the first shaping layer to the filtration layer; and v) a second adhesive layer that adheres the second shaping layer to the filtration layer.

Abstract: A filtration media array is provided having at least one contoured polymeric film layer having surface structures. The film layers may be configured as a stack that has the contoured film layer defining a plurality of ordered inlet openings through a face of the stack and corresponding air pathways, thereby forming an open, porous volume. The air pathways may be defined by a plurality of flow channels formed by the contours of the structured contoured film layers.

Abstract: The present invention relates to a fan-forced positive pressure breathing apparatus commonly known as a Powered Air Purifying Respirators (PAPR) system, and specifically concerns the connecting of the breathing components of such equipment. The invention is a method and apparatus for rapid engagement of PAPR breathing components (such as air supply lines and filter elements to a blower housing). The invention also provides for indicating and/or monitoring whether the relative components have been aligned and coupled in sealed engagement.

Abstract: This disclosure relates to a method for making a polymeric article mold, a method for making a polymeric article with that mold, and improved surface topography features for a polymeric article. A prototype article is formed and then coated with a thin conductive layer. The coated prototype article is then electroformed until nickel plated to a sufficient depth to define a nickel plating tool. After the prototype article has been removed from the mold face of the nickel tool, the tool can be used as a mold for forming finished polymeric articles which replicate the original prototype article. The use of fine topography features such as a dense upstanding stem array on the surface of the prototype article facilitates accurate and complete electroforming by increased surface area presentation. The disclosure also presents improvements to microreplicated surface structures such as stem arrays.

Abstract: A filtration media is formed from at least one structured polymeric layer, wherein a structured surface is defined within the layer. Layers may be configured as a stack that has the structured surfaces defining a plurality of ordered inlets open through a face of the stack and corresponding ordered fluid pathways, thereby forming an ordered, porous volume. The ordered fluid pathways may be defined by a plurality of flow channels formed within the structured surfaces of the structured layers, or may be defined by a plurality of protuberances formed in an ordered pattern within the structured surfaces of the structured layers.

Abstract: An active fluid separation device for removing a constituent of a fluid mixture. The separation device formed from a first polymeric structured layer having a plurality of flow channels defined in one surface, and a selectively permeable fluid separation media covering at least some of the flow channels. An external source is also included to provide a potential over the flow channels to promote movement of the fluid through the separation media, thereby removing a constituent component of the fluid mixture. A manifold in fluid contact with the flow channels of the structured layer may also be used to operatively permit the source to provide the potential over the flow channels.

Abstract: A unidirectional valve, wherein the valve comprises a valve body including a frame, a valve opening through the frame, and a valve seat extending from the frame and at least partially surrounding the valve opening. The valve further includes a valve flap having a first portion attached to the frame and an adjacent second portion free to move from a first position where the second portion is in contact with at least a part of the valve seat to a second position where at least part of the second portion is spaced from the valve seat, wherein the valve flap has a contour profile. The contoured profile may be along the length of the valve flap, between the point of attachment of the flap to the frame and the flap end, or from one flap side edge to a second side edge.

Abstract: An electrofiltration process is provided having at least one electrostatically charged polymeric film layer having surface structures. The film layers may be configured as a collection cell that has the structured film layer defining a plurality of ordered inlet openings through a face of the collection cell and corresponding air pathways, thereby forming an open, porous volume. The air pathways are defined by a plurality of flow channels formed by the structured film layers. The electrofiltration process is coupled with an ionizer which actively induces charges onto the particles to be removed by the collection cell.

Abstract: An electrofiltration apparatus is provided having at least one electrostatically charged polymeric film layer having surface structures. The film layers may be configured as a collection cell that has the structured film layer defining a plurality of ordered inlet openings through a face of the collection cell and corresponding air pathways, thereby forming an open, porous volume. The air pathways are defined by a plurality of flow channels formed by the structured film layers. The electrofiltration apparatus is coupled with an ionizer which actively induces charges onto the particles to be removed by the collection cell.

Abstract: Liquid dispensers comprising a reservoir including a plurality of elongated channels formed from overlaying layers of microstructured film having a dispensing edge, each elongated channel having an outlet at the dispensing edge, wherein liquid can be stored in the reservoir, and a transfer element in fluid communication with the dispensing edge of the reservoir that provides a location from which liquid stored in the reservoir can be controllably dispensed.

Abstract: A heat exchanger utilizing active fluid transport of a heat transfer fluid is manufactured with multiple discrete flow passages provided by a simple but versatile construction. The microstructured channels are replicated onto a film layer which is utilized in the fluid transfer heat exchanger. The surface structure defines the flow channels which are generally uninterrupted and highly ordered. These flow channels can take the form of linear, branching or dendritic type structures. A cover layer having favorably thermal conductive properties is provided on the structured bearing film surface. Such structured bearing film surfaces and the cover layer are thus used to define microstructure flow passages. The use of a film layer having a microstructured surface facilitates the ability to highly distribute a potential across the assembly of passages to promote active transport of a heat transfer fluid.

Abstract: A filtration media having at least one structured polymeric layer, wherein a structured surface is defined within the layer. Layers may be configured as a stack that has the structured surfaces defining a plurality of ordered inlets open through a face of the stack and corresponding ordered fluid pathways, thereby forming an ordered, porous volume. The ordered fluid pathway may be defined by a plurality of flow channels formed within the structured surfaces of the structured layers, or may be defined by a plurality of protuberances formed in an ordered pattern within the structured surfaces of the structured layers.

Abstract: A heat exchanger utilizing active fluid transport of a heat transfer fluid has multiple discrete flow passages provided by a simple but versatile construction. The microstructured channels are replicated onto a film layer which is utilized in the fluid transfer heat exchanger. The surface structure defines the flow channels which are generally uninterrupted and highly ordered. These flow channels can take the form of linear, branching or dendritic type structures. A cover layer having favorably thermal conductive properties is provided on the structured bearing film surface. Such structured bearing film surfaces and the cover layer are thus used to define microstructure flow passages. The use of a film layer having a microstructured surface facilitates the ability to highly distribute a potential across the assembly of passages to promote active transport of a heat transfer fluid. The thermally conductive cover layer then effects heat transfer to an object, gas, or liquid in proximity with the heat exchanger.

Abstract: An electrofiltration apparatus is provided having at least one electrostatically charged polymeric film layer having surface structures. The film layers may be configured as a collection cell that has the structured film layer defining a plurality of ordered inlet openings through a face of the collection cell and corresponding air pathways, thereby forming an open, porous volume. The air pathways are defined by a plurality of flow channels formed by the structured film layers. The electrofiltration apparatus is coupled with an ionizer which actively induces charges onto the particles to be removed by the collection cell.

Abstract: An active fluid transport device (10, 40, 54, 60) that includes a layer (12) of polymeric material. The layer (12) has a structured surface (13) that includes a plurality of substantially discrete flow channels (16). The flow channels (16) have a minimum aspect ratio of about 10 to 1 and a hydraulic radius no greater than about 300 micrometers. The device may also include a connector (20, 55) that allows a potential source (14) external to the structured surface (13) to be placed in fluid communication with the discrete flow channels (16). The potential source (14) promotes fluid movement through the flow channels (16) from a first location to a second location.

Abstract: A heat exchanger utilizing active fluid transport of a heat transfer fluid is manufactured with multiple discrete flow passages provided by a simple but versatile construction. The microstructured channels are replicated onto a film layer which is utilized in the fluid transfer heat exchanger. The surface structure defines the flow channels which are generally uninterrupted and highly ordered. These flow channels can take the form of linear, branching or dendritic type structures. A cover layer having favorably thermal conductive properties is provided on the structured bearing film surface. Such structured bearing film surfaces and the cover layer are thus used to define microstructure flow passages. The use of a film layer having a microstructured surface facilitates the ability to highly distribute a potential across the assembly of passages to promote active transport of a heat transfer fluid.

Abstract: A filtration media array is provided having at least one contoured polymeric film layer having surface structures. The film layers may be configured as a stack that has the contoured film layer defining a plurality of ordered inlet openings through a face of the stack and corresponding air pathways, thereby forming an open, porous volume. The air pathways may be defined by a plurality of flow channels formed by the contours of the structured contoured film layers.

Abstract: A fluid guide device that can evenly and effectively distribute the potential from a fluid transport source over an area substantially larger than the opening of a source conduit. The fluid guide device includes a first major surface having a structured surface that includes a plurality of flow channels disposed thereon. The flow channels extend from a first point to a second point along the structured surface and have a minimum aspect ratio of about 10:1 and a hydraulic radius no greater than about 300 micrometers (.mu.m). The fluid guide device also includes an active fluid transport source provided external to the structured polymeric surface to provide a potential over the flow channels to promote movement of matter through the flow channels from a first potential to a second potential. The fluid transport source is connected with a plurality of the flow channels of the structured surface by way of a manifold.

Abstract: A flexible pressure vessel 20 having an aperture 44 through one wall 30 of the vessel 20, which aperture 44 can be closed by a closure flap 50 having sufficient surface area of adhesive 52 to completely surround the aperture 44. The adhesive 52 has sufficient peel strength to prevent the vessel 20 from being reused after closure, and the vessel 20 is capable of withstanding a pressure differential of at least 75 kPa for at least thirty minutes.