A nonwoven fabric is formed of fibers of 0.10 μm or more and 5.00 μm or less. The nonwoven fabric includes a coarse layer portion and a dense layer portion. In the coarse layer portion, a void volume Pc is at least 90% and an average pore diameter Dc is in a range of 0.5 μm or more and 50 μm or less. In the dense layer portion, a void volume Pd is at least 70% and a relative standard deviation of pore diameter distribution is 20% or less.

A manufacturing method enabling the obtainment of a functional part essentially formed in a metallic material, all or part of the functional part delimiting a filtering medium permeable to a fluid and delimiting first and second main faces for a preferred circulation of the gas through the filtering medium. The method includes a main phase consisting of an additive manufacturing method in successive passes from a support tray. Each pass includes the deposition of at least one layer of the metallic material, the deposited material adhering to the metallic material deposited before. The deposition is controlled at each pass so the stack of metallic material constitutes the functional part. The filtering medium includes a coalescent network of connecting strands interconnected according to a three-dimensional spatial distribution between the faces, the connecting strands of the network delimiting therebetween pores spatially distributed within the filtering medium in three dimensions between the faces.

The present application relates to a polypropylene with high melt flow index and a method for producing the same, and meltblown fiber fabrics. A reacting mixture is firstly provided, and a polymerization process is performed to the reacting mixture in a slurry reaction system to obtain the polypropylene. The reacting mixture includes propylene monomers, Ziegler-Natta catalysts, organoaluminum compounds and electron donor. The polypropylene has high melt flow index and adjustable melting point and molecular weight distribution, such that it is used to produce the meltblown fiber fabrics.

A macro electrically active mask includes two conductive layers separated by at least one filtering and insulating layer. The conductive layers are connected to each other by a power source. The power source includes an oscillator and a high voltage transformer. The power source generates a periodic voltage with a fundamental frequency and multiple harmonic frequencies. The power source is connected between the two conductive layers and the periodic voltage generates a periodic electric field between the two conductive layers. The fundamental frequency, the duty cycle, and the amplitude of the periodic voltage are configured to inactivate the microorganism that pass through the electric field.

A pillar shaped honeycomb structure includes: a porous partition wall that defines a plurality of cells, the cells forming flow paths for a fluid, the cells extending from an inflow end face to an outflow end face; and an outer peripheral wall located at the outermost circumference. The cells include: a plurality of cells A wherein a side of the inflow end face is opened and the outflow end face has a plugged portion; and a plurality of cells B wherein a side of the outflow end face is opened and the inflow end face has a plugged portion, the cells B being arranged alternately with the cells A. One or both of the plugged portion of the cells A and the plugged portions of the cells B contain a magnetic substance and glass.

This depth filter comprises a substrate layer, a filtration layer, and a skin layer in this order. The substrate layer and the skin layer are layers obtained by winding and thermally fusing a nonwoven cloth configured from fibers having an average fiber diameter of 150 μm or more. The filtration layer is a layer obtained by winding a layered body two or more times, the layered body containing at least a net and a nonwoven cloth included only in the filtration layer. The average fiber diameter of the nonwoven cloth constituting the substrate layer and the average fiber diameter of the nonwoven cloth constituting the skin layer are larger than the average fiber diameter of the nonwoven cloth included only in the filtration layer.

A ceramic honeycomb filter has (a) cross section areas of intake flow paths being larger than those of discharge flow paths; (b) the intake and discharge flow paths having octagonal cross section shapes with four-fold rotation symmetry each obtained by cutting off four corners from a square; (c) the intake and discharge flow paths being alternately arranged in a first direction and a second direction perpendicular to the first direction, such that their opposing sides are parallel; (d) the opening ratio of the intake flow paths being 45-60%; (e) the number of the flow paths per cm.sup.2 being 30-60; (f) the thickness t1 of a cell wall between an intake flow path and a discharge flow path adjacent to that intake flow path being 0.150-0.260 mm; and (g) the thickness t2 of a cell wall between adjacent intake flow paths meeting 1.175<t2/t1<1.6.

A composite virucidal filter media is described. The filter media comprises a fibrous substrate comprising a plurality of intermingled fibers, a low cost, nontoxic, hydrophilic polymer without acidic functional groups deposited on a surface of the fibers without the formation of a continuous coating layer on the substrate, and a virucidal metal, a virucidal metal-containing compound, or combinations thereof deposited on the surface of the fibers comprising the hydrophilic polymer without acidic functional groups. The hydrophilic polymer without acidic functional groups can be charged or non-charged. Methods of making virucidal fibrous filter media are also described.

A filter element including a filter media and methods for making the same are provided. The filter element includes a support core surrounded by a tubular ring of filter media. A first end of the tubular ring of filter media is coupled to a first end cap and a second end of the tubular ring of filter media coupled to a second end cap. The tubular ring of filter media includes a carrier media layer, a coarse filter media layer, a fine filtration media layer, a water-capturing media layer, and an outer wrap.

Filter media comprising non-woven fiber webs having one or more advantageous physical properties are generally described. In some embodiments, a filter media and/or non-woven fiber web described herein comprises a combination of fibers that results in enhanced physical properties. For example, the non-woven fiber web may comprise a combination of fiber types that is advantageous, such as a combination comprising fibrillated fibers, glass fibers, and/or binder fibers. In some cases, the filter media and/or non-woven fiber web comprising the combination of fibers may be formed into undulations (e.g., by a creping and/or microcreping process) to further enhance the physical properties of the filter media and/or non-woven fiber.