A method for producing a fiber mat that includes: dispersing fibers having a fiber length smaller than a pore diameter of a papermaking wire in a dispersion medium; and matting the dispersed fibers including papermaking the dispersed fibers on a microporous sheet having a pore diameter smaller than that of the papermaking wire and disposed on the papermaking wire.

A method for producing a fiber mat that includes: dispersing fibers having a fiber length smaller than a pore diameter of a papermaking wire in a dispersion medium; and matting the dispersed fibers including papermaking the dispersed fibers on a microporous sheet having a pore diameter smaller than that of the papermaking wire and disposed on the papermaking wire.

Paper making machine comprising a forming zone in which a layer of fibrous material is formed, a zone for forced removal of water from the fibrous material layer downstream of the forming zone, a drying zone downstream of the forced removal of the water, and a paper collection zone downstream of the drying zone, and means for transporting the layer of fibrous material through said zones of the machine along a path that follows a predetermined transport direction (MD). The forced water removal zone comprises, in turn, two consecutive zones (Z1, Z2) along said transport direction (MD), in which a capillary roller (44) and a pressure element (4S) with a respective counter-roller (4C) are respectively arranged, acting consecutively on the layer of fibrous material upstream of the drying zone.

Paper making machine comprising a forming zone in which a layer of fibrous material is formed, a zone for forced removal of water from the fibrous material layer downstream of the forming zone, a drying zone downstream of the forced removal of the water, and a paper collection zone downstream of the drying zone, and means for transporting the layer of fibrous material through said zones of the machine along a path that follows a predetermined transport direction (MD). The forced water removal zone comprises, in turn, two consecutive zones (Z1, Z2) along said transport direction (MD), in which a capillary roller (44) and a pressure element (4S) with a respective counter-roller (4C) are respectively arranged, acting consecutively on the layer of fibrous material upstream of the drying zone.

A method for producing a foam-formed multilayered substrate that includes producing an aqueous-based foam including at least 3% by weight non-straight synthetic binder fibers, wherein the non-straight synthetic binder fibers have an average length greater than 2 mm; forming together a wet sheet layer from the aqueous-based foam and a cellulosic fiber layer, wherein the cellulosic fiber layer includes at least 60 percent by weight cellulosic fibers; and drying the combined layers to obtain the foam-formed multilayer substrate. A multilayered substrate includes a first layer including at least 60 percent by weight non-straight synthetic binder fibers having an average length greater than 2 mm; and a second layer including at least 60 percent by weight cellulosic fiber, wherein the first layer is in a facing relationship with the second layer, and wherein the multilayered substrate has a wet/dry tensile ratio of at least 60%.

A method for producing a foam-formed multilayered substrate that includes producing an aqueous-based foam including at least 3% by weight non-straight synthetic binder fibers, wherein the non-straight synthetic binder fibers have an average length greater than 2 mm; forming together a wet sheet layer from the aqueous-based foam and a cellulosic fiber layer, wherein the cellulosic fiber layer includes at least 60 percent by weight cellulosic fibers; and drying the combined layers to obtain the foam-formed multilayer substrate. A multilayered substrate includes a first layer including at least 60 percent by weight non-straight synthetic binder fibers having an average length greater than 2 mm; and a second layer including at least 60 percent by weight cellulosic fiber, wherein the first layer is in a facing relationship with the second layer, and wherein the multilayered substrate has a wet/dry tensile ratio of at least 60%.

There is provided a method of producing a paper having a grammage according to ISO 536 of 50-250 g/m.sup.2, a Gurley value according to ISO 5636-5 of above 15 s and a stretchability according to ISO 1924-3 in the machine direction of at least 9%, said method comprising the steps of: a) providing a pulp, preferably sulphate pulp; b) subjecting the pulp to refining; c) diluting the pulp from step b) and adding the diluted pulp to a forming wire to obtain a paper web; d) pressing and the paper web from step c); e) drying the paper web from step d); f) compacting the paper web from step e) in a Clupak unit at a moisture content of 32-50%, preferably 37-49%, more preferably 41-49%; g) calendering the paper web from step f), optionally after drying, at a moisture content of 21-40%, preferably 30-40%, more preferably 32-39%; h) drying the paper web from step g).

There is provided a method of producing a paper having a grammage according to ISO 536 of 50-250 g/m.sup.2, a Gurley value according to ISO 5636-5 of above 15 s and a stretchability according to ISO 1924-3 in the machine direction of at least 9%, said method comprising the steps of: a) providing a pulp, preferably sulphate pulp; b) subjecting the pulp to refining; c) diluting the pulp from step b) and adding the diluted pulp to a forming wire to obtain a paper web; d) pressing and the paper web from step c); e) drying the paper web from step d); f) compacting the paper web from step e) in a Clupak unit at a moisture content of 32-50%, preferably 37-49%, more preferably 41-49%; g) calendering the paper web from step f), optionally after drying, at a moisture content of 21-40%, preferably 30-40%, more preferably 32-39%; h) drying the paper web from step g).

An installation for producing a fibrous material web, in particular a long-fiber paper or wet nonwoven web, contains a binder wire section having a binder wire for applying an aqueous binder to the fibrous material web, and a dryer section having a dryer fabric for drying and consolidating the fibrous material web. The binder wire section and the dryer section are arranged at a distance from each other, so that the fibrous material web is led from the binder wire to the dryer fabric in a free draw. At least one air extraction device is arranged at the edge of the installation in the region of the distance between the binder wire section and the dryer section.

A device and a method for the production of a fiber mat is suitable in particular for use in the production of packaging board or fibrous construction elements, from a fibrous source material. The method includes providing the fibrous source material, low-water processing of the fibrous source material in an airflow into raw material including individual fibers and/or fiber bundles, forming of the individual fibers and/or fiber bundles in the airflow by a dry forming method into a fiber mat in such a way that a spatial or three-dimensional structure is formed by the fiber mat and consolidation of the formed fiber mat. The specific volume of the fiber mat is greater than 1.6 cm.sup.3/g, in particular greater than 2 cm.sup.3/g, preferably greater than 3 cm.sup.3/g, and the fiber mat thickness 1 mm, in particular 1.5 mm, preferably 2 mm.