A filtering film includes a porous substrate and a membrane disposed on the porous substrate. The membrane includes a plurality of fibers of one or more bio-degradable materials. The fibers have an average diameter of about 50 nm to about 3 μm. The one or more bio-degradable materials has a melt flow index of at least 5 g/10 min at 210° C. at a load of 2.16 kg.

A nanofiber nonwoven product is disclosed which comprises a polyamide with a relative viscosity from 2 to 330, spun into nanofibers with an average diameter of less than 1000 nanometers (1 micron). In general, the inventive products are prepared by: (a) providing a polyamide composition, wherein the polyamide has a relative viscosity from 2 to 330; (b) melt spinning the polyamide composition into a plurality of nanofibers having an average fiber diameter of less than 1 micron, followed by (c) forming the nanofibers into the product.

Filter media, filter elements, and methods for filtering an gas stream are described herein. In some embodiments, the filter media may comprise a fiber web comprising a plurality of fibers and having a particular oil repellency level. For instance, in certain embodiments, the surface chemistry of the fiber web may be tailored to impart a particular surface energy density that matches the surface energy density of the fluid (e.g., an oil, a lubricant, and/or a cooling agent) being removed from the gas stream. In some embodiments, the fiber web may be wrapped around a core. For example, the fiber web may be wrapped around the core such that it forms two or more layers around the core. In some cases, the fiber web may be perforated. In certain embodiments, an gas stream comprising a fluid (e.g., an oil, a lubricant, and/or a cooling agent) may be passed through the fiber web, filter media, and/or filter element such that at least a portion of the fluid coalesces on the fiber web. Fiber webs, filter media, and/or filter elements as described herein may be particularly well-suited for applications that involve filtering gas streams containing oil, lubricants, and/or cooling agents (e.g., gas streams generated by a compressor) though the media may also be used in other applications. Advantageously, the fiber webs, filter media, and/or filter elements described herein may significantly reduce or prevent fouling of the filter caused by oil or other liquids.

Group of inventions relates to multilayer filtration materials for liquid or gas purification, which can be used purification systems for liquids, for example water from various sources, including drinking water, in ventilation systems or air filtration or for personnel or collective protective equipment production, including respiratory protective equipment, produced based on filtration materials.

Filtration material for liquid or gas purification, consisting of at least two layers, which liquid or gas flows one by one, where first layer is coarse filtration layer and is made on the base of nonwoven fibrous material, and second layer is a fine filtration layer on the base of filtration paper and/or filtration cardboard, characterized in that is configured to sorption filtration of liquid or gas, therein coarse filtration layer contains the particles with size of 2 to 500 mkm, predominantly from 5 to 200 mkm, at least of one type of sorbent, retained in the structure of nonwoven fibrous material, predominantly due to mechanical forces, and the second fine filtration layer contains particles with e size of 0.05 to 20 mkm, predominantly from 0.2 to 5 mkm of at least one fine-dispersed sorbent, retained in the structure of filtration paper and/or filtration cardboard predominantly due to adhesive forces.

Personal protective equipment made as helmet, consisting of body from predominantly transparent polymeric material with air inlet and outlet, collar from elastic polymeric material, and contains at least one air circulation means, therein air inlet and outlet openings are equipped with filters made of filtration material of the claim 1, therein in the inlet filter coarse filtration layer goes first to the environment, and the outlet filter—second fine layer of the filtration material.

Filter media, filter elements, and methods for filtering an gas stream are described herein. In some embodiments, the filter media may comprise a fiber web comprising a plurality of fibers and having a particular oil repellency level. For instance, in certain embodiments, the surface chemistry of the fiber web may be tailored to impart a particular surface energy density that matches the surface energy density of the fluid (e.g., an oil, a lubricant, and/or a cooling agent) being removed from the gas stream. In some embodiments, the fiber web may be wrapped around a core. For example, the fiber web may be wrapped around the core such that it forms two or more layers around the core. In some cases, the fiber web may be perforated. In certain embodiments, an gas stream comprising a fluid (e.g., an oil, a lubricant, and/or a cooling agent) may be passed through the fiber web, filter media, and/or filter element such that at least a portion of the fluid coalesces on the fiber web. Fiber webs, filter media, and/or filter elements as described herein may be particularly well-suited for applications that involve filtering gas streams containing oil, lubricants, and/or cooling agents (e.g., gas streams generated by a compressor) though the media may also be used in other applications. Advantageously, the fiber webs, filter media, and/or filter elements described herein may significantly reduce or prevent fouling of the filter caused by oil or other liquids.

Fibrous filtration media for hot oil filtration includes a nonwoven fibrous web containing synthetic fibers and at least about 15 wt. %, based on total weight of the fibrous web, of a binder component selected from thermoset binder resins and/or binder fibers. The synthetic fibers of the fibrous web will contain from about 2 wt. % to about 65 wt. %, for example between about 10 wt. % to about 50 wt. %, based on total weight of fibers in the fibrous web, of thermoplastic synthetic microfibers having an average diameter of less than 5μ.Math.τ.Math.. The synthetic fibers are bonded together with the binder component to form the fibrous web which is capable of forming a self-supporting, pleated oil filter media which retains pleats upon contact with oil having a temperature in a range encountered in an internal combustion engine.

Filter media, such as electret-containing filtration media for filtering gas streams (e.g., air), are described herein. In some embodiments, the filter media may be designed to have desirable properties such as stable filtration efficiency over the lifetime of the filter media, increased normalized gamma, relatively low pressure drop (i.e. resistance), and/or relatively low basis weight. In certain embodiments, the filter media may be a composite of two or more types of fiber layers where each layer may be designed to enhance its function without substantially negatively impacting the performance of another layer of the media. For example, one layer of the media may be designed to have a relatively low basis weight and/or a relatively high air permeability, and another layer of the media may be designed to have stable filtration efficiency and/or a relatively high efficiency throughout the filter media's lifetime. The filter media described herein may be particularly well-suited for applications that involve filtering gas streams (e.g., face masks, cabin air filtration, vacuum filtration, room filtration, furnace filtration, respirator equipment, residential or industrial HVAC filtration, high-efficiency particulate arrestance (HEPA) filters, ultra-low particular air (ULPA) filters, medical equipment), though the media may also be used in other applications.

An air filter medium includes a glass filter medium layer that includes a glass fiber. The glass filter medium layer has a protruding portion. The protruding portion undergoes a change in protrusion height of 70% or less when left to stand at an atmospheric temperature of 100° C. for one hour.

High efficiency and high capacity glass-free filtration media include a blend of synthetic non-fibrillated staple fibers and fibrillated cellulosic staple fibers, wherein the fibrillated cellulosic fibers are present in the media in an amount to achieve a multipass dust holding capacity of 10 mg/in.sup.2 and greater, and a multipass filtration efficiency at 1.5 microns of greater than 50%. The filtration media is made by forming a wet laid sheet from a fibrous slurry blend of the synthetic non-fibrillated staple fibers and fibrillated cellulosic staple fibers, followed by drying the sheet to obtain the filtration media. Optionally, the filtration media may be provided with a resin binder and may be grooved and/or pleated.

A face mask containing a network of conductive activated carbon meso-fibers crosslinked with a crosslinking agent bonded to a insulative polymeric micro-fiber based purification element. The purification element is captured between two ridged porous elements and contacted to the face by a biocompatible flexible polymeric seal. Optionally the front cover attaches to a main frame of the mask through a system of sliding locks that are coupled with bayonet latch mechanisms. The face mask attaches to the head of a wearer through a harness that couples with the sliding locks or alternatively with a biocompatible adhesive.