A nonwoven fabric according to the present invention is formed so that constituent fibers of the nonwoven fabric have an average fiber diameter of less than 1 m and the number of fibers having fiber diameters ranging from 2 times up to 10 times the average fiber diameter of the constituent fibers is in a range of 2 to 20% of a total number of the constituent fibers. When the nonwoven fabric according to the present invention is used as a filter layer constituting an air filter, for example, it is possible to achieve high collection efficiency while reducing clogging (packing) between fibers to solve problems that may occur in using the conventional nanofiber nonwoven fabric (such as an increase in pressure loss and a decrease in service life).

Disclosed is a composite filter media. The composite filter media is formed from multiple layers of media material including a nanofiber media layer, where the layers are laminated, bound, or otherwise composited to each other. The composite filter media can comprise at least one nanofiber layer comprising polymeric media material having a geometric mean fiber diameter of about 100 nm to 1 ?m, and fibers configured in a gradient such that ratio of the geometric mean diameter of fibers at the upstream face of the nanofiber layer to the geometric mean diameter of fibers at the downstream face of the nanofiber layer is about 1.1 to 2.8, preferably about 1.2 to 2.4.

Provided are a filter medium for an air filter capable of having extended life even when composed of embossable material. The filter medium (1) has a tensile elongation of 10% or greater, and includes a main collection layer (30) having a filing rate of 5% to 15%, a thickness of 0.35 mm to 0.70 mm, and a peak in a fiber diameter distribution at less than 1.0 m and a peak at 1.0 m or greater. An average fiber diameter of small fiber diameters of less than 1.0 m is from 0.1 m to less than 0.8 m, and an average fiber diameter of large fiber diameters of 1.0 m or greater is from 1.2 m to less than 3.0 m. A volume ratio of the fibers having the small fiber diameter to the fibers having the large fiber diameter is from 30:70 to 80:20.

Composite filter media is formed from multiple layers of media material including a nanofiber media layer, where the layers are laminated, bound, or otherwise composited to each other. The composite filter media can comprise at least one nanofiber layer comprising polymeric media material having a geometric mean fiber diameter of about 100 nm to 1 ?m, and fibers configured in a gradient such that ratio of the geometric mean diameter of fibers at the upstream face of the nanofiber layer to the geometric mean diameter of fibers at the downstream face of the nanofiber layer is about 1.1 to 2.8, preferably about 1.2 to 2.4.

Carbon fiber composite additives, media incorporating the carbon fiber composites, and related methods are provided herein. In some aspects, a composition includes at least one medium; and a carbon fiber composite incorporated with the at least one medium, the carbon fiber composite including one or more carbon fibers with an epoxy resin matrix applied thereto to produce a composition having improved characteristics and filtration performance.

Porous structures are made from compositions that include hollow glass bodies and an inorganic powder. The inorganic powder may act as a rigid frame member, a crystallization agent, or both, which reduces the shrinkage of the porous structures during firing. The porous structures made therefrom have an open porosity of greater than 70% and reduced shrinkage of less than 10% compared to the green structures prior to firing. Methods for firing the green structures made from the compositions are also disclosed, the firing methods including reducing a temperature ramping rate of the green structures during a crystallization temperature range of the glass of the hollow bodies.

A filter material of microspheres bonded in a close-packed arrangement is provided. A filter device comprising a funnel containing a filter material of microspheres bonded in a close-packed arrangement is provided. The filter material and filter device are suitable for plasma separation from whole blood.

The present invention is directed toward an improved air filtration medium comprising a single layer polymeric nanofibrous web comprising a single source randomly intermingled fiber network with electrostatic charge up to 20 kV, a filtration efficiency range from about 70% to about 99.99%, and an air resistance less than about 2.5 mm wg for 0.3 diameter micron particles. The air filtration medium is made from a centrifugal melt spinning process.

The present invention aims to provide a leukocyte depletion filter that has both higher leukocyte removal performance and higher blood permeability than conventional filters. The leukocyte depletion filter according to the present invention includes a filter material having an average fiber diameter of 0.30 to 1.60 m and a coefficient of variation of fiber diameter of at least 0.40 but not more than 1.20.

The present application is direction to a system and method for preparing filter media from macro and nanofibers by ventilating a nanofiber media, combining the nanofiber media with macro fibers to form a hybrid media, inserting the hybrid media between a stitching plate and a stripper plate and alternatively inserting and withdrawing needles to combine the macro fibers with the nanofiber media and create a fiber web along at least one surface of the nanofiber media.