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.

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.

A method for producing a composite filter tube and filter element made of a multilayer metal mesh and metal powders, including: knitting to obtain metal meshes of different mesh numbers, obtaining a layered structure by means of a lamination method, then putting the layered structure in a vacuum furnace for sintering processing, sintering a metal composite layer to obtain a composite filter sheet and tube made of a multilayer metal mesh and metal powders with a multilayer metal mesh as a structure support layer and a metal powder sinter structure as a filter layer, then rolling the composite filter sheet and tube into a tubular filter element by using a shaping machine, and welding to obtain a composite filter tube and filter element product made of a multilayer metal mesh and metal powders.

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.

A facemask manufacturing process is described. A first and a second assembly of strips are provided superposed one on the other, each of the first and the second assembly of strips comprising a first strip of filtering material, a second strip of filtering material and an elastic strip interposed between the first strip of filtering material and the second strip of filtering material. Then the first and second assemblies of strips are cut in order to form, in a top-to-tail position, a first facemask and a second facemask respectively having a median line corresponding to the first weld line and to the second weld line and orifices intended for receiving a user's ears.

The present invention provides a laminated sheet, a cylindrical filter element, and a filtration kit that are used to perform water filtration. Specifically, the laminated sheet used to perform water filtration includes: a pre-filtration layer, the pre-filtration layer including a first fiber having a diameter within a range of 1-5 m and a second fiber having a diameter within a range of 200-900 nm, and the pre-filtration layer having a pore diameter within a range of 0.2-1 m; and a fine filtration layer, the fine filtration layer having a pore diameter within a range of 0.02-0.5 m, wherein the pore diameter of the pre-filtration layer is greater than the pore diameter of the fine filtration layer. The laminated sheet used to perform water filtration and the cylindrical filter element and the filtration kit including the same according to the technical solution of the present invention have an extremely small pressure difference, high filtration efficiency, and a long service life.

The filter for gel shearing and particle filtration of molten polymer has a first layer of metal fibers of an average equivalent diameter between 8 and 65 m. The cross-section of the metal fibers has two neighboring straight sides with an included angle of less than 90 and one or more irregularly shaped curved sides. The metal fibers have an average length of at least 6 mm. The metal fibers are bonded to each other by metal bonds; where the metal of the metal fibers of the first layer is the bonding agent forming the metal bonds. The filter has a second layer of metal fibers. The average equivalent diameter of the metal fibers of the second layer is smaller than the average equivalent diameter of the metal fibers of the first layer.

The present invention provides a nonwoven fabric sheet for use in extraction filters having high sealing strength and extraction filters manufactured using the nonwoven fabric sheet. The nonwoven fabric sheet includes a first layer including a spunbonded nonwoven fabric formed from a polyester-based resin having an IV value of 0.60 to 1.00, a crystallinity of 30% to 80%, a crystalline orientation of 60% to 95%, and a birefringence (n) of 0.040 to 0.100 and provided with a partial thermocompression bonding section whose thermocompression bonding area rate is in the range of 5% to 30%, and a second layer including a meltblown nonwoven fabric formed from a polyester-based resin blown onto a surface of the first layer and solidified to have a crystallinity of 0% to 14%. The extraction filters are formed by sealing by welding the nonwoven fabric sheet with the second layer of the sheet placed inside.

An annular filter includes a first annulus wall and a second annulas wall being impermeable to fluid (liquid and gas), a first circular wall and a second circular wall mounted between the first annulas wall and second annulas wall wherein the first and second circular wall are permeable to fluid (liquid and gas), at least one dividing wall mounted between the first and second circular wall to divide an internal volume defined between the first and second annulas wall and the first and second circular wall into channels, bisecting walls between the first and second circular walls to change a direction of fluid flow from a first direction to a second direction first and second channels, turbulator walls mounted channel, wherein the turbulator walls cause turbulent fluid flow in the channels, and a filter media positioned in at least one of the channels.