Abstract: A nonwoven web, containing at least one first homogeneous layer consisting of a blend of at least one of defibrated natural plant based fibers, individualized natural plant based fibers and staple fibers is provided. The nonwoven web contains no binder, adhesive or thermal bonding fibers and a basis weight of the at least one homogeneous layer is from 20 g/m2 to 100 g/m2. When a weighted average fiber length of the blend is greater than about 4.0 mm, the nonwoven web is a non-dispersible product which does not meet the requirement for dispersibility in accordance with INDA/EDANA GD4, and when a weighted average fiber length of the blend is less than about 4.0 mm, the nonwoven web is a dispersible product as defined in accordance with INDA/EDANA GD4. Methods to prepare the nonwoven web are provided.

Abstract: The present invention relates to a filter medium comprising a substrate and a fine fiber layer on top of the substrate, wherein the substrate comprises a first layer comprising first fibers having a first average diameter and a first maximum fiber length; a second layer comprising second fibers having a second average diameter and a second maximum fiber length; and a third layer comprising third fibers having a third average diameter and a third maximum fiber length; wherein the boundary area between the first and the second layer forms a first blended area comprising first and second fibers; and the boundary area between the second and the third layer forms a second blended area comprising second and third fibers; and wherein the first and the third average diameters are each larger than the second average diameter.

Abstract: The present invention relates to a filter medium comprising a substrate and a fine fiber layer on top of the substrate, wherein the substrate comprises a first layer comprising first fibers having a first average diameter and a first maximum fiber length; a second layer comprising second fibers having a second average diameter and a second maximum fiber length; and a third layer comprising third fibers having a third average diameter and a third maximum fiber length; wherein the boundary area between the first and the second layer forms a first blended area comprising first and second fibers; and the boundary area between the second and the third layer forms a second blended area comprising second and third fibers; and wherein the first and the third average diameters are each larger than the second average diameter.

Abstract: A nonwoven web, containing at least one first homogeneous layer consisting of a blend of at least one of defibrated natural plant based fibers, individualized natural plant based fibers and staple fibers is provided. The nonwoven web contains no binder, adhesive or thermal bonding fibers and a basis weight of the at least one homogeneous layer is from 20 g/m2 to 100 g/m2. When a weighted average fiber length of the at least one of defibrated natural plant based fibers, individualized natural plant based fibers and staple fibers is greater than about 4.0 mm, the nonwoven web is a non-dispersible product which does not meet the requirement for dispersibility in accordance with INDA/EDANA GD4, and when a weighted average fiber length of the at least one of defibrated natural plant based fibers, individualized natural plant based fibers and staple fibers is less than about 4.0 min, the nonwoven web is a dispersible product as defined in accordance with INDA/EDANA GD4.

Abstract: The present invention relates to a filter medium comprising a substrate and a fine fiber layer on top of the substrate, wherein the substrate comprises a first layer comprising first fibers having a first average diameter and a first maximum fiber length; a second layer comprising second fibers having a second average diameter and a second maximum fiber length; and a third layer comprising third fibers having a third average diameter and a third maximum fiber length; wherein the boundary area between the first and the second layer forms a first blended area comprising first and second fibers; and the boundary area between the second and the third layer forms a second blended area comprising second and third fibers; and wherein the first and the third average diameters are each larger than the second average diameter.

Abstract: The present invention relates to a filter medium comprising a substrate and a fine fiber layer on top of the substrate, wherein the substrate comprises a first layer comprising first fibers having a first average diameter and a first maximum fiber length; a second layer comprising second fibers having a second average diameter and a second maximum fiber length; and a third layer comprising third fibers having a third average diameter and a third maximum fiber length; wherein the boundary area between the first and the second layer forms a first blended area comprising first and second fibers; and the boundary area between the second and the third layer forms a second blended area comprising second and third fibers; and wherein the first and the third average diameters are each larger than the second average diameter.

Abstract: The present invention relates to a filter medium comprising a substrate and a fine fiber layer on top of the substrate, wherein the substrate comprises a first layer comprising first fibers having a first average diameter and a first maximum fiber length; a second layer comprising second fibers having a second average diameter and a second maximum fiber length; and a third layer comprising third fibers having a third average diameter and a third maximum fiber length; wherein the boundary area between the first and the second layer forms a first blended area comprising first and second fibers; and the boundary area between the second and the third layer forms a second blended area comprising second and third fibers; and wherein the first and the third average diameters are each larger than the second average diameter.

Abstract: The present invention relates to a filter medium comprising a substrate and a fine fiber layer on top of the substrate, wherein the substrate comprises a first layer comprising first fibers having a first average diameter and a first maximum fiber length; a second layer comprising second fibers having a second average diameter and a second maximum fiber length; and a third layer comprising third fibers having a third average diameter and a third maximum fiber length; wherein the boundary area between the first and the second layer forms a first blended area comprising first and second fibers; and the boundary area between the second and the third layer forms a second blended area comprising second and third fibers; and wherein the first and the third average diameters are each larger than the second average diameter.

Abstract: A non woven web containing water insoluble nanofibers and/or microfibers obtained by an electrospinning process using water based solution containing at least two components, a first component having carboxylic acid and/or anhydride functionalities and a second component having primary and/or secondary amino functionalities, the web being cured upon a heat treatment. Application: filtration and separation.