Respiratory devices and methods for their manufacture and use are disclosed. The device features a resiliently deformable element configured to form a perimeter seal with the inner nostril wall and to swab the distal portion of the internal nostril region with a disinfectant during device installation. A first filter stage includes a first filter layer characterized by first geometric convolutions and a first MPPS1 value; and a second filter stage includes a second filter layer characterized by second geometric convolutions and a second MPPS2 value.

In a method for producing a filter medium, at least one substrate layer of a nonwoven comprising cellulose fibers and/or synthetic polymer fibers is provided and a fiber layer of polymer fibers is deposited on the at least one substrate layer. Prior to depositing the fiber layer, a solvent is applied to the at least one substrate layer, wherein a material of the substrate layer and/or a material of the fiber layer is soluble in the solvent. A filter medium produced by the method has material-fused connections at crossing points of the polymer fibers and/or cellulose fibers of the substrate layer with the polymer fibers of the fiber layer.

In a method for producing a filter medium, at least one substrate layer of a nonwoven comprising cellulose fibers and/or synthetic polymer fibers is provided and a fiber layer of polymer fibers is deposited on the at least one substrate layer. Prior to depositing the fiber layer, a solvent is applied to the at least one substrate layer, wherein a material of the substrate layer and/or a material of the fiber layer is soluble in the solvent. A filter medium produced by the method has material-fused connections at crossing points of the polymer fibers and/or cellulose fibers of the substrate layer with the polymer fibers of the fiber layer.

The present disclosure provides a filtration element comprising a proximal filtration layer, a distal filtration layer and at least one filtration layer placed between said proximal filtration layer and said distal filtration layer, each filtration layer comprising a non-woven (NW) fabric having a filtration degree; wherein the proximal filtration layer and the distal filtration layer have, independently, a filtration degree that is lower than the filtration degree of the at least one filtration layer placed between said proximal filtration layer and said distal filtration layer. Also provided by the present disclosure is a personal protective equipment comprising the disclosed filtration element and a method of protecting a subject body using the same.

The present disclosure relates to a multilayer fabric media comprising a non-woven membrane of fibers comprising at least one polymer in combination with at least one photoreactive agent mounted on a woven or non-woven substrate and coated with a light transmissible protective layer, to methods of forming such multilayer fabric media, and to articles of manufacture made therewith.

Filter media are described. The filter media may include multiple layers. In some embodiments, the filter media include a nanofiber layer adhered to another layer. In some embodiments, the layer to which the nanofiber layer is adhered is formed of multiple fiber types (e.g., fibers that give rise to structures having different air permeabilities and/or pressure drops). In some embodiments, the nanofiber layer is adhered to a single-phase or a multi-phase layer. In some embodiments, the nanofiber layer is manufactured from a meltblown process. The filter media may be designed to have advantageous properties including, in some cases, a high dust particle capture efficiency and/or a high dust holding capacity.

A filtration barrier comprises at least one barrier layer which includes polymeric nanofibers interlaced with microfibers, and at least one substrate layer which includes polymeric microfibers. The filtration barrier can be made by electrospinning process.

One aspect of the technology relates to a recirculation filter. The recirculation filter has a first outer layer defining at least a portion of a first flow face of the recirculation filter, where the first flow face is configured to be positioned adjacent to a sensitive component in an electronics enclosure. A second outer layer defines at least a portion of a second flow face of the recirculation filter. A filter material layer is disposed between the first outer layer and the second outer layer. The filter material layer has a central region, wherein a substantial portion of the central region is offset from the first flow face of the recirculation filter. Other aspects are also described.

A mask according to an embodiment of the present disclosure includes a filter structure provided in a form in which a plurality of members are laminated, and a fiber sheet coupled to a circumferential part of the filter structure and configured to come into contact with a user's face, wherein the fiber sheet may be manufactured using an isotropic fiber sheet.

The filter device has a high-temperature filter medium and a low-temperature filter medium. The high-temperature filter medium includes a high-temperature resin that melts above a first melting-temperature. The low-temperature filter medium includes a low-temperature resin which melts above a second melting-temperature which is lower than the first melting-temperature. The low-temperature filter medium is disposed in a layer in which a temperature for forming a welded portion is hard to rise. In the welded portion, both the high-temperature resin and the low-temperature resin are welded. A welding step supplies heat so that heat is transferred from the high-temperature filter medium to the low-temperature filter medium. In the welding step, melted resins are cured to form the welded portion after melting both the high-temperature resin and the low-temperature resin.