This disclosure describes a filter medium that minimizes the adverse effects of variations in flow rate on filter medium efficiency without a corresponding increase in pressure drop. The filter medium includes a support layer, a continuous fine fiber layer, and an efficiency layer. The continuous fine fiber layer includes a continuous fine fiber that has a diameter of up to 10 micrometers and is located downstream of the efficiency layer.

An object of the present invention is to provide a separation substrate having a high megakaryocyte blocking rate and a high platelet permeation rate, and a cell separation filter and a method for producing a platelet which use the same. The separation substrate of the present invention is a separation substrate including non-woven fabric for separating a platelet from a cell suspension containing a megakaryocyte and the platelet, in which an average pore diameter of the separation substrate is 2.0 μm to 15.0 μm, and a thickness of the separation substrate is 10 μm to 500 μm.

A thermoplastic core-sheath fiber comprises: a polymer fiber core having a coextensive sheath layer disposed thereon, and an electrostatic charge enhancing additive. The sheath layer may comprise poly(4-methyl-1-pentene) and the fiber core and the sheath layer have different compositions. At least one of the fiber core or the sheath layer comprises an electret charge. A nonwoven fibrous web comprising the core-sheath fibers and a respirator including the nonwoven fibrous web are also disclosed.

A nanofiber for an air filter and a method for manufacturing the same are proposed. The nanofiber may include a styrene-(meth)acrylate-acrylonitrile random copolymer having a zwitterionic functional group in a side chain. The nanofiber can greatly enhance the bonding of particulate matter (PM) particles with the surface of a polymer by having a high dipole moment derived from the zwitterionic functional group, thereby providing high efficiency of filtration (>99.9%) of the PM particles. Furthermore, the nanofiber can be very usefully used as a core material for air purifier filters and vehicle air purification filters by having low airflow resistance and excellent antibacterial properties.

The present invention generally relates to a dual density air filtration media that comprises a plurality of nanofibers layers formed from nanofibers having different fiber diameters. Due to the presence of these multiple nanofiber layers with different nanofiber diameters, the resulting filtration media of the present invention comprises a gradient density. In particular, the present invention uses a novel combination of two or more layers of nanofibers made via an electrospinning process, wherein the nanofiber layers made up from different fiber sizes are strategically applied to a cellulose or synthetic base material or substrate, to thereby maximize the filtration efficiency and dust holding capacity of the resulting filtration media.

Articles such as filter media, which include dendrimers and/or other components, are provided. The filter media may further include a water repellant (e.g., a fluorinated species) to impart desirable properties to the media such as high water repellency. The filter media may also have a high efficiency as a function of pressure drop (i.e., high gamma values). In some embodiments, the filter media includes a fiber web which may be formed of various components such as glass fibers. The fiber web can also include additional components such as synthetic fibers, binder components, as well as other additives. The media may be incorporated into a variety of filter element products.

A product and method of manufacturing and producing antimicrobial fibers using an antimicrobial additive material. The method comprising using various antimicrobial metals incorporated and embedded into an inorganic material as metal ions within the additive material that can be formulated into a masterbatch precursor material and processed to manufacture fine or synthetic fibers using standard manufacturing processes for use in applications from face masks and respirators to air filters for HVAC and higher efficiency HEPA applications.

A device and a method for removing fats, oils and/or grease (“FOGs”) from water comprise a separator, wherein the separator removes the FOGs that separate from the water under gravity, and a filter wherein the filter removes the FOGs remaining in the water after the water has passed through the separator. The filter comprises several layers having different compositions suitable for removing FOGs from water, including a layer comprising granular activated carbon bonded together and wrapped in polyester.

An object is to provide a blood processing filter favorable in both of the effectiveness (leukocyte removing performance) and the safety (reduction in the amount of elutable substances). The object can be achieved by a blood processing filter comprising a filtration medium including a polyester fiber, wherein a surface area of the filtration medium is 6.0 m.sup.2 or more, and a maximum absorbance of an aqueous extract of the blood processing filter in the range from 240 to 245 nm is 0.03 or less.

A moisture-retentive fabric medium includes a hydrophilic, thermoplastic polyester fiber as a blend of from 10-905% or 20-80% by total weight of textile fibers and 90-10% or 80-20% by total weight of hydrophilic textile fibers and less than 0.5% by weight of total fabric medium as microfibrillated cellulose fiber and less than 0.05% by weight superabsorbent polymers, the polyester having a melting point between 190-500 F when measured in accordance with ASTM D-3418.