A filter media construct includes a plurality of flexible laminas joined in a stack, each lamina including an array of nanofibers extending from a surface thereof. Each lamina is configured to be permeable to a fluid such that the fluid can flow through each lamina normal to the surface thereof and in any direction along at least a portion of said surface when the fluid is flowed through the construct. The laminas can include a plurality of perforations extending therethrough such that the fluid flows through at least some of the perforations of the laminas when the fluid is flowed through the construct. A contaminant contained in the fluid is at least partially filtered from the fluid by the nanofibers when the fluid is flowed along the surface of any lamina or into or through the perforations.

A method for preparing a composite filter medium (1), comprising a step of forming a first filter medium (8) through deposition of nanofibers (4) on a base fabric (2) through an electrospinning process and a step of covering said filter medium (1) by plasma deposition of a coating (7) on said first filter medium (8) in a vacuum chamber (9). According to the invention, after the electrospinning process and before the plasma deposition of the coating (7), a degassing step of the base fabric (2) and of the nanofibers (4) forming the aforementioned first filter medium (8) is provided inside the same chamber (9). With respect to the known filter media, that of the invention offers the advantage of maintaining the desired level of water and oil repellency, due to the formation of a completely polymerized coating strongly adhering to the surface of the base fabric and of the nanofibers.

A filter medium is provided. The filter medium according to an embodiment of the present invention comprises: a first support body having a plurality of pores; a nanofiber web comprising nanofibers disposed on upper and lower sides of the first support body and forming a three dimensional network structure; and a second support body having a plurality of pores interposed between the first support body and the nanofiber web, wherein the nanofiber web is realized as a filter medium that satisfies: (1) an elongation of 25% or more, (2) an air permeability of 0.1 to 2.00 cfm, and 3) porosity of 60%˜85%. Accordingly, since the filter medium has a fixed level of mechanical properties of the nanofiber web, the shape, structure deformation, and damage of the filter medium are minimized and a flow path is smoothly secured during a water treatment operation so that the filter medium can have a high flow rate. In addition, since the filter medium of the present invention has a prolonged use life due to excellent durability of the filter medium even at high pressure applied during backwashing, and has excellent filtration efficiency and water permeability, the filter medium can be applied in various ways in various water treatment fields.

Embodiments disclosed herein include a stitched filtering fabric including a barrier layer configured to inhibit air flow through the filtering fabric, a yarn stitched through and forming a plurality of stitch holes in the barrier layer, and a first yarn layer comprising interlocking loops of the yarn. The barrier layer is configured to direct air flow through the yarn within the stitched holes.

A porous electrospun polymeric nanofiber liquid filtration medium, such as an electrospun mats, used for the removal of viral particles (e.g., parvovirus) and other particles in the 18 nm to 30 nm size range from fluid streams, having a mean flow bubble point measured with perfluorohexane above 100 psi. The electrospun medium includes nanofibers having an average fiber diameter of about 6 nm to about 13 nm, and the nanofiber liquid filtration medium has a mean pore size ranging from about 0.01 μm to about 0.03 μm, a porosity ranging from about 80% to about 95%, a thickness ranging from about 1 μm to about 100 μm, and a liquid permeability greater than about 10 LMH/psi. The high porosity of the electrospun mats enable much higher water fluxes, thus reducing the time required to complete virus filtration steps on a fluid stream.

Described herein is an antiviral face mask and methods of use thereof to inactivate a virus in contact with the face mask. The face mask may include a fibrous material with silicon nitride powder impregnated therein and a layer surrounding the fibrous material. In some embodiments, silicon nitride is present in the fibrous material at a concentration of about 30 wt. % to about 50 wt. %.

A composite multi-layer textile, comprising at least one nanofibre layer with nanofibres with diameters below 100 nm and one support layer with microfibres with diameters below three microns, wherein the layers were produced by electrospinning. The multi-layer textile shows a general transmittance at #=550 nm greater than 60%, which shows improved properties concerning transparency, breathability and robustness. This is achieved in that the at least one nanofibre layer and the support layer are fused, forming solid domains in the multi-layer textile, at closed areas of a pattern used in the production process, wherein the solid domains are separated from each other or connected, showing defined shapes, with regular or irregular spatial distribution, while the fibre morphology of nanofibres of the nanofibre layer and microfibres of support layer is preserved on top of the open areas beside the solid domains, attaining a general transmittance greater than that given by the sum of the individual layers.

Articles and methods involving filter media are generally provided. In certain embodiments, the filter media includes at least a first layer, a second layer, and an adhesive resin positioned between the first layer and the second layer. In some embodiments, the first layer may be a pre-filter layer or a support layer. The second layer may, for example, comprise fibers formed by a solution spinning process and/or may comprise fine fibers. In some embodiments, the adhesive resin may be present in a relatively low amount and/or may have a low glass transition temperature. The filter media as a whole may have one or more advantageous properties, including one or more of a high stiffness, a high bond strength between the first layer and the second layer, a high gamma, and/or a low increase in air resistance after being subjected to an IPA vapor discharge. The filter media may be, for example, a HEPA filter and/or an ULPA filter.

A layer for a protective mask (100a, 100b, 200a) comprises at least a first sublayer (122b, 218b), wherein the first sublayer (122b, 218b) includes a first substrate and a layer of a plurality of nanoparticles (124b, 7) of a nanomaterial provided on the first substrate. The protective mask (100a, 100b, 200a) includes an outer layer (120b, 230a) which is made of an organic fibular network bonded with nanomaterials. An air filtration element (900, 1070, 1240) for attenuation of airborne contaminants includes negatively charged nanodiamonds (920, 1320). A filter (1100, 1200, 1500, 1600) for an air conditioning system (1130, 1530) or an air purifier (1230, 1630) comprises the air filtration element (900, 1070, 1240). An air treatment element (1140,1300,1540,1640) comprises nanodiamonds (920,1320) including colour centers. The protective mask (100a, 100b, 200a), the air filtration element (900, 1070, 1240), the air treatment element (1140,1300,1540,1640) and the filter (1100, 1200, 1500, 1600) overcome or at least partially ameliorate some of the deficiencies as associated with those of the prior art.

In order to address the sustainability and environmental issues associated with conventional HVAC filters, inventive HVAC filters have been developed that are completely biodegradable and compostable and exhibit Minimum Efficiency Reporting Value (MERV) ratings that are superior to conventional HVAC filters. More particularly, it has been discovered that biodegradable electrospun nanofibers can be used to produce biodegradable HVAC filters that exhibit superior filtration performance relative to conventional HVAC filters produced from polypropylene electrostatic media or triboelectric nonwoven media.