Abstract: The invention relates to a method for producing a zigzag-folded nonwoven material for a filter, wherein the nonwoven material is produced by a melt-spinning process, comprising the following work steps: folding the nonwoven material by means of a folding device, whereby a plurality of folds results, wherein the folds divide the nonwoven material into first limbs and second limbs such that the nonwoven material is folded in zigzag form; and subsequently welding a weld region of the first limb of a fold to at least one weld region of the second limb of a fold by means of a thermal-contact welding process, wherein a welded joint is formed between the two facing sides of the limbs of a fold. The invention furthermore relates to a corresponding apparatus and a corresponding nonwoven material.

Abstract: The invention relates to a fibrous nonwoven, in particular for a filter medium, having a first layer, wherein at least one single-piece fiber strand of said first layer has a first fiber portion and a second fiber portion in the longitudinal direction, and wherein the fiber strand has a thickening substantially in said second fiber portion.

Abstract: A pleatable nonwoven material is provided, including thicker form-giving fibers and thinner fibers determining the filter effect, wherein the thinner fibers are incorporated largely homogeneously in the thicker fibers running in the direction along the surface of the nonwoven material and a distribution density gradient of the thinner fibers is established perpendicular to the surface of the nonwoven material such that the highest concentration of thinner fibers is in the region of the center or on one of the two outsides, wherein the thicker and thinner fibers are bonded together by solidification from the melted condition and are made from the same material.

Abstract: The invention relates to a fibrous nonwoven, in particular for a filter medium, having a first layer, wherein at least one single-piece fiber strand of said first layer has a first fiber portion and a second fiber portion in the longitudinal direction, and wherein the fiber strand has a thickening substantially in said second fiber portion.

Abstract: An air filter medium consisting of a non-woven is provided, which is produced using a melting and spinning method and has a depth filter constituent and a surface filter constituent, wherein the air filter medium is configured such that it has long-lasting functionality owing to the depth filter constituent and can be substantially regenerated with a reverse pulse owing to the surface filter constituent.

Abstract: The invention relates to a filter medium consisting of a synthetic polymer, comprising a first layer of a non-woven produced by means of a melt-spinning method. An electrostatic charge can be applied to said first layer of a non-woven and the polymer has a melt-flow-Index between 20-200, preferably between 40-100 and even more preferably from 60, the non-woven layer has, in particular, a soft texture.

Abstract: The invention relates to a method for producing a nonwoven fabric (1), in particular a filter medium or air filler medium consisting of a nonwoven, in a melt-spinning method comprising the following steps: Melting a raw material, spraying the raw material from at least one spinning die (6) and capturing the raw material on a support layer (12) such that the nonwoven fabric (1) is formed. The support layer (12) has structures, so that spacers (2) are formed in the nonwoven fabric (1).

Abstract: A pleatable nonwoven material is provided, including thicker form-giving fibers and thinner fibers determining the filter effect, wherein the thinner fibers are incorporated largely homogeneously in the thicker fibers running in the direction along the surface of the nonwoven material and a distribution density gradient of the thinner fibers is established perpendicular to the surface of the nonwoven material such that the highest concentration of thinner fibers is in the region of the center or on one of the two outsides, wherein the thicker and thinner fibers are bonded together by solidification from the melted condition and are made from the same material.

Abstract: A pleatable nonwoven material is provided, including thicker form-giving fibers and thinner fibers determining the filter effect, wherein the thinner fibers are incorporated largely homogeneously in the thicker fibers running in the direction along the surface of the nonwoven material and a distribution density gradient of the thinner fibers is established perpendicular to the surface of the nonwoven material such that the highest concentration of thinner fibers is in the region of the center or on one of the two outsides, wherein the thicker and thinner fibers are bonded together by solidification from the melted condition and are made from the same material.

Abstract: Air filter medium from a non-woven fabric, which is produced in a melt-spinning process and comprises a depth filter component and a surface filter component, the air filter medium being designed such as to have a long service life and the surface filter component allowing regeneration by way of a reverse pulse.

Abstract: A pleatable nonwoven material is provided, including thicker form-giving fibers and thinner fibers determining the filter effect, wherein the thinner fibers are incorporated largely homogeneously in the thicker fibers running in the direction along the surface of the nonwoven material and a distribution density gradient of the thinner fibers is established perpendicular to the surface of the nonwoven material such that the highest concentration of thinner fibers is in the region of the center or on one of the two outsides, wherein the thicker and thinner fibers are bonded together by solidification from the melted condition and are made from the same material.

Abstract: A pleatable nonwoven material is provided, including thicker form-giving fibers and thinner fibers determining the filter effect, wherein the thinner fibers are incorporated largely homogeneously in the thicker fibers running in the direction along the surface of the nonwoven material and a distribution density gradient of the thinner fibers is established perpendicular to the surface of the nonwoven material such that the highest concentration of thinner fibers is in the region of the center or on one of the two outsides, wherein the thicker and thinner fibers are bonded together by solidification from the melted condition and are made from the same material.