Filter media comprising non-woven fiber webs and having one or more advantageous structural properties are generally described. In some embodiments, a filter media and/or non-woven fiber web described herein has one or more properties that are both beneficial and easily obtainable by undulating the non-woven fiber web, such as by performing a creping procedure. This property may be characteristic of the procedure employed to form the undulations (e.g., creping and/or microcreping), or may be attainable via one or more methods of undulation.

Provided are an air filter medium and an air filter product that can have a long life. The air filter medium includes a filter medium layer that includes first fibers having an average fiber diameter of not less than 5 μm and not greater than 50 μm and second fibers disposed in gaps between the first fibers and having an average fiber diameter of not less than 30 nm and not greater than 1 μm.

Producing a filtration body formed of a layered double hydroxide having a crystallite size of 20 nm or less carried on a carrier including a thermally fusible fiber is described. The carrier is prepared that has a first mesh carrier having a first mesh size and a second mesh carrier provided above the first mesh carrier. The second mesh carrier has a second mesh size larger than the first mesh size. A layered double hydroxide in the form of granules is supplied toward the second mesh carrier. The first mesh carrier carries the layered double hydroxide that has passed through the second mesh carrier. The carrier is shaken so that a portion of the layered double hydroxide (e.g., at least one granule) passes through the first and second mesh carriers. Thereafter, the layered double hydroxide carried on the first mesh carrier is adhered by thermally fusing the thermally fusible fiber.

Filter media and filters comprising a fibrous material, a bonding material, and a flame-resistant treatment composition are disclosed herein. Methods of making and using the same are also disclosed herein.

A non-woven fabric body (11) that forms a non-woven fabric (1) is formed by integrating composite polyester fibers (2) and flame-retardant acrylic fibers (3) which serve as the other fibers of the rest. The composite polyester fibers (2) have a core-sheath structure in which a sheath portion (4) is formed of a low melting point polyester and a core portion (5) is formed of a high melting point polyester having a higher melting point than that of the low melting point polyester. The composite polyester fibers (2) are contained in an amount of 15% to 80% by weight in a total of 100% by weight of the non-woven fabric body (11). Further, an apparent density of the non-woven fabric body (11) ((a basis weight of the non-woven fabric body)/(a thickness of the non-woven fabric body)) is 0.005 g/cm.sup.3 to 0.040 g/cm.sup.3. In addition, a bending resistance of the non-woven fabric body (11) in a flow direction of the fibers is 50 mN.Math.cm to 220 mN.Math.cm, and a bending resistance in a width direction that is orthogonal to the flow direction is 20 mN.Math.cm to 140 mN.Math.cm.

Filter media comprising fluorinated water-repellent additives and/or water-repellent additives having minimal or no fluorine atoms are generally provided. Filter media disclosed herein may include fluorinated water-repellent additives but not water-repellent additives having minimal or no fluorine atoms, water-repellent additives having minimal or no fluorine atoms but not fluorinated water-repellent additives, or both fluorinated water-repellent additives and water-repellent additives having minimal or no fluorine atoms.

The invention provides an antimicrobial fiber which exhibits excellent antimicrobial properties even without the addition of antimicrobial agents and can remain antimicrobial even after repeated washing. The antimicrobial fiber comprises a fiber having on a surface thereof a polyacetal copolymer (X) containing oxyalkylene groups, the molar amount of oxyalkylene groups in the polyacetal copolymer (X) being 0.2 to 5 mol % relative to the total of the molar amount of oxymethylene groups and the molar amount of oxyalkylene groups.

A system for thermally bonding nonwoven fibers of assemblages of nonwoven fibers loosely held together may include a processing duct including an inlet end, an outlet end, and an intermediate portion extending between the inlet end and the outlet end. The system also may include one or more heat inlets located in the intermediate portion and configured to facilitate introduction of heat and air flow into the intermediate portion. The system further may include an inlet air feed at the inlet end and configured to separate the assemblages upon entry into the inlet end and propel the assemblages into the intermediate portion. The system also may include one or more heating devices configured to heat the assemblages as the assemblages are conveyed toward the outlet end to form processed assemblages, each of the processed assemblages including at least some nonwoven fibers adhered to one another.

A filter material that contains a non-woven fabric is provided. When the amount of deformation of the filter material is 10 mm, its three-point bending strength is 2.0 MPa or greater.

Provided are antimicrobial nonwovens comprising antimicrobial chemical treated fibers and untreated binder fibers. 0.0003-0.1 wt. % of one or more silver containing antimicrobial chemicals are used in nonwovens to provide an excellent antimicrobial/antiviral property. Exemplary applications and methods of manufacturing antimicrobial products such as a facial covering, a mattress cover, a surface cover and an air filter are provided.