Methods for the production of fibrous materials and the fibrous materials obtainable by these methods and their uses

Description

[0001] The present invention relates to a process for producing fiber materials, in particular nonwoven mats or nonwoven panels, e.g., insulation mats. Furthermore, the invention relates to fiber materials, in particular nonwoven mats or nonwoven panels, e.g., insulation mats, obtainable by the process according to the invention. Furthermore, the invention relates to the use of the fiber materials according to the invention for sound and / or thermal insulation or for furniture production.

[0002] Thermal insulation of exterior facades is becoming increasingly important against a backdrop of increasingly scarce resources and rising energy costs. Both insulation boards based on foamed plastics, such as EPS insulation boards, and insulation boards based on natural fibers, such as hemp fiber insulation boards, are used for this purpose. To obtain natural fibers for insulation mats from suitable plant materials, these are often broken down and further processed using wet or dry processes that require a lot of equipment and energy, for example, by removing shives. Shives are the woody components of the plant material. Shives regularly complicate the processing of plant materials into insulation mats. This can be particularly true for extremely long fibers.Ships, and in particular fibers from bast plant materials such as hemp or flax, have high tensile strength and therefore damage rotating elements in processing plants. Ships can also lead to blockages in the feed lines of production plants. For this reason, the shives are regularly separated from the fiber material before the shredded plant materials are reused for nonwoven production. However, the prior art processes for isolating plant fibers are generally very energy-intensive and therefore expensive. A process for producing fiberboards that uses the entire crop or cultivated plant is known from DE 875 137. These fibers are shredded in a suitable milling device together with water until they are feltable.The fiber pulp is then deposited on a permeable substrate by suction or pressing to form a board, which can then be further compacted in subsequent steps and impregnated with impregnating and binding agents. This process is very complex and requires costly drying steps.

[0003] According to DE 196 30 828 A1, compostable nonwovens, which can also be used as insulation materials, are obtained by using as a binder at least one biodegradable polymer containing ester and / or ether compounds in the basic structure.

[0004] According to DE 198 46 104 A1, an insulating mat with a high insulating effect is to be made accessible by enclosing the insulating mat on both sides with laminations and by placing so-called volume-giving spacers made of essentially unrefined hemp fibre products between these laminations.

[0005] EP 2 963 167 A1 relates to a method for producing nonwoven mats comprising the steps: a) providing first comminuted plant material containing plant fibers and shives, wherein the plant fibers and shives are at least partially bonded to one another, b) providing at least one binder, d) producing a first material layer from the first comminuted plant material containing plant fibers and shives in a first feed device, j) discharging the mixture onto a conveyor belt to form a fiber web, l) forming a pre-woven fabric by means of at least one first web former comprising at least one needle roller or a drum, and / or by means of at least one web spreader, wherein the mixture is preferably fed to the web former or web spreader by means of a first transport unit, n) applying at least one particulate binder to the pre-woven fabric,o) Forming a nonwoven from the pre-fleece according to step l) or n) by means of a second nonwoven former comprising a drum, wherein the pre-fleece is preferably fed to the drum by means of a second transport unit comprising at least one pair of upper and lower rollers or comprising an upper roller and a feed table, and u) Separating the consolidated nonwoven into fiber nonwoven mats, in particular insulation mats. Such a process is intended to reliably produce insulation mats from renewable raw materials, even with the use of shives, which are characterized by a homogeneous distribution of the components forming the insulation mats, good thermal insulation properties comparable to those of foamed plastic insulation boards, and, at the same time, good stability and mechanical strength.

[0006] FR 2 990 221 A1 refers to a heat and sound insulation material consisting of cereal straw wool mixed with a binder 100 % of plant origin. The binder is present in an amount of between 8 and 50 % of the weight of the material in the composition. This 100 % The plant-based material consists of lignin or potato starch, or a mixture of these two components. Due to its composition of lignin and / or potato starch, such a thermal and sound insulation material is intended to allow use in residential construction without releasing volatile organic compounds (VOCs).

[0007] EP 3 135 811 A1 relates to a process for producing pulp for the production of boards, in which cereal straw is shredded into plates with a length of 10 to 50 mm, which are then subjected to a hydrothermal treatment. The resulting mass is injected between the grinding plates of the defibration unit using a feeding machine and is then compressed using a screw press until an absolute moisture content of less than 50 is reached. %pressed. The resulting mass is then fluffed into pulp form and dried. In this process, the cut cereal straw flakes are subjected to a hydrothermal treatment using a water mixture at a temperature below 50°C, with the hydrothermal treatment lasting no longer than 1 minute. This process is intended to reduce the energy consumption of the production process both by reducing the thermal energy required to heat the water and by reducing the electrical energy required to carry out the fluffing process. Furthermore, the risk of charring / burning of fibers on circular knives in subsequent production steps is also to be reduced.

[0008] EP 2 963 198 A1 claims a method for producing a flame-retardant nonwoven mat, in particular an insulating mat, comprising a) providing comminuted plant material containing plant fibers or comminuted plant material containing plant fibers and shives, b) providing at least one binder, c) providing at least one flame retardant, d) producing a material layer having an upper and a lower side from the comminuted plant material, f) mixing the comminuted plant material with at least one binder, g1) discharging the fiber mixture onto a conveyor belt to form a fiber web having an upper and a lower side and treating the fiber web with at least one flame retardant, and / or g2) discharging the fiber mixture onto a conveyor belt to form a fiber web,Forming a pre-woven fabric with a top and a bottom side by means of at least one nonwoven spreader and / or by means of at least one nonwoven former containing at least one needle roller or a drum, and treating the pre-woven fabric with at least one flame retardant, h) forming a nonwoven fabric with a top and a bottom side from the fibrous web according to step g1) or from the pre-woven fabric according to step g2) by means of at least one nonwoven former, in particular an aerodynamic nonwoven former containing a drum, and j) consolidating the nonwoven fabric to form the nonwoven fiber mat, in particular an insulating mat. This process is intended to enable the production of insulation boards from renewable raw materials, which provides insulation boards with sufficient flame retardancy, in particular without having to accept any loss in their mechanical and / or thermal insulation properties, and which can nevertheless be operated economically.

[0009] DE 22 29 405 A1 relates to a process for the production of building elements for the construction industry from cellulose-containing materials and / or minerals using residues from mineral oil and / or coal distillation as well as resin. Furthermore, the claimed process is characterized in that 15 to 85 wt. % cellulosic material and / or mineral, 1 to 15 wt. % one or more alkali metal hydroxides and / or one or more alkaline earth metal hydroxides, 1 to 45 wt. % Residues of mineral oil and / or coal distillation and 1 to 10 wt. %Resin and, if necessary, a foaming agent are heated to a temperature of 120 to 250°C, and the resulting material is then thermoformed. This should enable the production of building elements for the construction industry from cellulose-containing materials and / or minerals with good thermal insulation properties, heat resistance up to at least 100°C, high compressive strength, and moisture resistance, while also having a low density.

[0010] WO 2008 / 107664 A1 relates to a fiber mat comprising fibers of plant origin arranged in a fibrous network and a material of plant origin that differs from the fibers of plant origin and is held within the fibrous network to provide a mat structure. The claimed method is intended to make it possible to provide fiber mats from fibers of plant origin.

[0011] In the production of high-quality insulation mats made from grain straw, it has often proven disadvantageous that grain straw can only be conveyed in a controlled manner using conventional conveyor systems to a limited extent or not at all due to its pronounced waxy and therefore very smooth coating. This smooth surface of the stalks prevents these components of the straw from sticking to each other or to other objects.

[0012] When manufacturing insulation boards made from renewable raw materials, it should not be overlooked that these compete with foamed insulation boards made from plastic materials. The latter generally have good insulating properties, which are achieved due to the homogeneity of the material across the entire insulating surface. On the other hand, it can sometimes be difficult to achieve a sufficiently homogeneous material distribution within the insulation mat, for example with insulation boards made from hemp plants, which contain shives. This lack of homogeneous distribution is just as detrimental to adequate thermal insulation as it is to the stability required of the insulation boards. While the stability of such an insulation board can be increased by stronger consolidation and the use of a larger amount of binding agents, this usually results in a deterioration of the thermal insulation properties.

[0013] It would therefore be desirable to be able to use a process for the production of fibre materials, in particular insulation mats or insulation boards, from renewable raw materials that is not afflicted with the shortcomings of the state of the art.

[0014] The object of the present invention was therefore to provide a process by which fiber materials, in particular insulation mats or insulation boards, can be obtained in a reliable manner, which are characterized by a homogeneous distribution of the components forming the fiber material, good thermal insulation properties comparable to those of foamed plastic insulation boards, and at the same time good stability and mechanical strength.

[0015] Accordingly, a process for producing fiber materials, in particular nonwoven fiber mats or nonwoven fiber boards, has been found, comprising a) Provision of cereal straw, in particular wheat straw, which is preferably at least partially pre-shredded, in particular shortened in length and optionally dried, wherein the cereal straw has a residual moisture content in the range of 5 to 20 percent by weight and wherein the proportion of cereal straw is at or above 70 percent by weight. %wherein the said proportion of cereal straw is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives. b) providing at least one binding agent, in particular binding fiber, c) providing a smaller amount, based on the amount of cereal straw, of comminuted bast plant material containing bast plant fibers and shives, in particular from the bast plant providing the bast plant fibers, wherein preferably the bast plant fibers and shives are at least partially bonded to one another, wherein the proportion of comminuted bast plant material is in the range of 2 to 20 wt. %wherein the said proportion of comminuted bast plant material is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives, wherein the comminuted bast plant material containing plant fibers and shives mainly comprises plant fibers and / or shives with an average length in the range of 2 to 15 cm, g) mixing the comminuted bast plant material containing bast plant fibers and shives according to c) with the cereal straw according to a) and the at least one binder according to b), in particular the at least one binder fiber, in particular in an air stream, h) separating dust and / or foreign particles from the resulting mixture, in particular by means of at least one cyclone separator and / or condenser, in particular a condenser, j) discharging the mixture according to g) or h) onto a conveyor belt to form a fiber web,n) optionally applying to the mixture at least one particulate binder, in particular in the form of powder, granules or fibers or any mixture thereof, q) applying to the mixture steam, in particular if a particulate binder, preferably in powder form, is added in step n), and / or r) activating the binder and optionally simultaneously or staggered applying to the mixture pressure, s) optionally calendering the mixture obtained according to step q) or r), t) if a heat treatment has taken place in step q), r) and / or s), at least partially cooling the mixture solidified according to step q, r) and / or s) and optionally applying to pressure and u) separating the solidified mixture to fiber materials, in particular nonwoven fiber mats or nonwoven fiber boards.

[0016] In an expedient embodiment, the method according to the invention also provides the following steps after step c): d) producing a first material layer from the comminuted bast plant material containing bast plant fibers and shives in a first feed device, e) producing at least one second material layer from the cereal straw according to a) in a second feed device, f) adding at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the first and / or second material layer and / or the cereal straw according to a), in particular applying an aqueous system containing at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the material layers from the top side and / or the bottom side, in particular the top side, g) mixing the comminuted bast plant material containing bast plant fibers and shives with the cereal straw according to a) and / or e) or f) and the at least one binder according to b), in particular the at least one binder fiber, in particular in an air stream.

[0017] In a further development, the method according to the invention can also make use of the following steps after step g) and before step k): i) intermediate storage of the mixture obtained after step g) or h) and j) discharge of the mixture according to i) onto a conveyor belt to form a fibre web.

[0018] Embodiments of the method according to the invention have also proven particularly advantageous in which, after step j), the following steps are provided: k) optionally treating the fiber web with at least one flame retardant and / or a hydrophobizing agent and / or a biocide, in particular applying an aqueous system containing at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the fiber web from the top side and / or the bottom side, in particular the top side, and in each case in particular at least one flame retardant, l) forming a pre-web by means of at least one first web former, in particular equipped with needles or pins, for example an aerodynamic web former, containing at least one needle roller or a drum, and / or by means of at least one web spreader, in particular comprising or consisting of at least one pin roller, wherein the mixture is preferably conveyed by means of a first transport unit, in particular comprising at least one pair of rollers comprising an upper and lower roller or an upper roller and a trough table,is fed to the nonwoven former or nonwoven spreader, m) optionally treating the pre-woven fabric with at least one flame retardant and / or a hydrophobizing agent and / or a biocide, in particular applying an aqueous system containing at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the pre-woven fabric from the top side and / or underside, in particular the top side, n) optionally applying at least one particulate binder, in particular in the form of powder, granules or fibers or any desired mixture thereof to the pre-woven fabric, in particular sprinkling the pre-woven fabric, o) forming a nonwoven fabric from the pre-woven fabric according to step l), m) or n) by means of a second, in particular aerodynamic, nonwoven former, in particular comprising a drum, in particular equipped with a sawtooth wire and / or a pin roller,wherein the pre-woven fabric is preferably fed to the second web former, in particular the drum, by means of a second transport unit containing at least one pair of upper and lower rollers or containing an upper roller and a feed table, p) optionally treating this web with at least one flame retardant and / or a hydrophobizing agent and / or a biocide, in particular applying an aqueous system containing at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the web from the top and / or bottom, in particular the top, and containing at least one flame retardant, in each case in particular at least one flame retardant, q) applying steam to the web, in particular if a particulate binder, preferably in powder form, is added in step n), and / or r) activating the binder by treating the web obtained according to step o), p) or q) with heat for the purpose of thermobonding the binder,in particular the binding fibers, and optionally applying pressure to the nonwoven fabric simultaneously or at different times, s) calendering the nonwoven fabric obtained according to step q) or r), t) if a heat treatment has taken place in step q), r) and / or s), cooling the nonwoven fabric consolidated according to step q, r) and / or s) and optionally applying pressure and u) separating the consolidated nonwoven fabric to form nonwoven fiber materials, in particular nonwoven fiber mats or nonwoven fiber sheets.

[0019] The advantages of the present invention are particularly also achieved with an embodiment of the method according to the invention comprising the following steps: a) Provision of cereal straw, in particular wheat straw, which is preferably at least partially pre-shredded, in particular shortened in length and optionally dried, wherein the cereal straw has a residual moisture content in the range of 5 to 20 percent by weight and wherein the proportion of cereal straw is at or above 70 percent by weight. %wherein the said proportion of cereal straw is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives. b) providing at least one binding agent, in particular binding fiber, c) providing a smaller amount, relative to the amount of cereal straw, of comminuted bast plant material containing bast plant fibers and shives, in particular from the bast plant providing the bast plant fibers, wherein preferably the bast plant fibers and shives are at least partially bonded to one another, wherein the proportion of comminuted bast plant material is in the range of 2 to 20 wt.%, wherein the said proportion of comminuted bast plant material is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives,wherein the comminuted bast plant material containing plant fibers and shives mainly comprises plant fibers and / or shives with an average length in the range of 2 to 15 cm, d) producing a first material layer from the comminuted bast plant material containing bast plant fibers and shives in a first feed device, e) producing at least one second material layer from the cereal straw according to a) in a second feed device, f) adding at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the first and / or second material layer and / or the cereal straw according to a), in particular applying an aqueous system containing at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the material layers from the top side and / or the bottom side, in particular the top side,g) Mixing the comminuted bast plant material containing bast plant fibers and shives with the cereal straw according to a) and / or e) or f) and optionally the at least one binding agent according to b), in particular the at least one binding fiber, in particular in an air stream, h) Separating dust and / or foreign particles from the resulting mixture, in particular by means of at least one cyclone separator and / or condenser, in particular a condenser, i) Optionally, intermediate storage of the mixture obtained after step g) or h), j) Discharge of the cereal straw according to a) or f) or the second material layer according to e) or f) or discharge of the mixture according to g), h) or i) onto a conveyor belt to form a fiber web, k) Optionally, treating the fiber web with at least one flame retardant and / or a hydrophobizing agent and / or a biocide, in particular applying the fiber web from the top and / or the bottom,in particular the upper side, with an aqueous system containing at least one flame retardant and / or a hydrophobizing agent and / or a biocide, in each case in particular at least one flame retardant, l) forming a pre-woven fabric by means of at least one first web former, in particular equipped with needles or pins, for example an aerodynamic web former, containing at least one needle roller or a drum, and / or by means of at least one web spreader, in particular comprising or consisting of at least one pin roller, wherein the mixture is preferably fed to the web former or web spreader by means of a first transport unit, in particular containing at least one pair of rollers comprising an upper and lower roller or an upper roller and a trough table, m) optionally treating the pre-woven fabric with at least one flame retardant and / or a hydrophobizing agent and / or a biocide,in particular applying an aqueous system containing at least one flame retardant and / or a hydrophobic agent and / or a biocide, in each case in particular at least one flame retardant, to the pre-woven web from the top side and / or underside, in particular the top side, n) optionally applying, in particular sprinkling the pre-woven web, at least one particulate binder, in particular in the form of powder, granules or fibers or any desired mixture thereof, o) forming a web from the pre-woven web according to step l), m) or n) by means of a second, in particular aerodynamic, web former, in particular containing a drum, in particular equipped with a sawtooth wire and / or a pin roller, wherein the pre-woven web is preferably fed to the second web former by means of a second transport unit containing at least one pair of upper and lower rollers or containing an upper roller and a feed table,in particular drum, p) optionally treating this nonwoven fabric with at least one flame retardant and / or a hydrophobizing agent and / or a biocide, in particular applying an aqueous system containing at least one flame retardant and / or a hydrophobizing agent and / or a biocide to the nonwoven fabric from the top side and / or underside, in particular the top side, and in each case in particular at least one flame retardant, q) applying steam to the nonwoven fabric, in particular if a particulate binder, preferably in powder form, is added in step n), and / or r) activating the binder by treating the nonwoven fabric obtained according to step o), p) or q) with heat for the purpose of thermobonding the binder, in particular the binding fibers, and optionally applying pressure to the nonwoven fabric simultaneously or at different times, s) optionally calendering the nonwoven fabric obtained according to step q) or r),t) if a heat treatment has taken place in step q), r) and / or s), cooling the nonwoven fabric consolidated according to step q, r) and / or s) and, if appropriate, applying pressure and u) separating the consolidated nonwoven fabric to form nonwoven materials, in particular nonwoven mats or nonwoven sheets.

[0020] The process according to the invention enables completely problem-free material transport of grain straw even in conventional compounding plants, allowing high-quality insulation-related fiber materials, especially nonwoven mats or nonwoven panels, to be reproducibly produced with consistently high quality. Without being bound by any theory, it is currently assumed that the surfaces of the bast plant materials possess sufficient grip to carry even the smooth grain straw components along during transport, without causing a so-called sedimentation process.

[0021] In an expedient embodiment of the method according to the invention, this comprises a) the provision of cereal straw, in particular wheat straw, where the cereal straw has a residual moisture content in the range of 5 to 20 percent by weight and where the proportion of cereal straw is at or above 70 percent by weight. %wherein the said proportion of cereal straw is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives. b) the provision of at least one binding agent, in particular binding fiber, c) the provision of a smaller amount, based on the amount of cereal straw, of comminuted bast plant material containing bast plant fibers and shives, in particular from the bast plant providing the bast plant fibers, wherein preferably the bast plant fibers and shives are at least partially bonded to one another, wherein the proportion of comminuted bast plant material is in the range from 2 to 20 wt. %wherein the said proportion of comminuted bast plant material is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives, wherein the comminuted bast plant material containing plant fibers and shives mainly comprises plant fibers and / or shives with an average length in the range of 2 to 15 cm, g) mixing the comminuted bast plant material containing bast plant fibers and shives with the cereal straw according to a) and optionally the at least one binder according to b), in particular the at least one binder fiber, in particular in an air stream, h) separating dust and / or foreign particles from the resulting mixture, in particular by means of at least one cyclone separator and / or condenser, in particular a condenser, j) discharging the mixture according to g) or h) onto a conveyor belt to form a fiber web,l) Forming a pre-woven web by means of at least one first web former, in particular equipped with needles or pins, for example an aerodynamic web former, containing at least one needle roller or a drum, and / or by means of at least one web spreader, in particular comprising or consisting of at least one pin roller, wherein the mixture is preferably fed to the web former or web spreader by means of a first transport unit, in particular containing at least one pair of upper and lower rollers or an upper roller and a trough table, n) optionally applying to the pre-woven web, in particular sprinkling the pre-woven web, with at least one particulate binder, in particular in the form of powder, granules or fibers or any desired mixture thereof, o) Forming a web from the pre-woven web according to step l) or n) by means of a second, in particular aerodynamic, web former, in particular containing a drum,in particular equipped with a sawtooth wire and / or a pin roller, wherein the pre-fleece is preferably fed to the second fleece former, in particular a drum, by means of a second transport unit containing at least one pair of upper and lower rollers or containing an upper roller and a feed table, r) activating the binder by treating the fleece obtained according to step o) with heat for the purpose of thermobonding the binder, in particular the binding fibers, and optionally applying pressure to the fleece simultaneously or at different times, t) cooling the fleece consolidated according to step r) and optionally applying pressure and u) separating the consolidated fleece to form fiber fleece materials, in particular fiber fleece mats or fiber fleece sheets.

[0022] In a preferred embodiment, the method according to the invention comprises the steps: a) the provision of a main quantity of cereal straw, in particular wheat straw, wherein the cereal straw has a residual moisture content in the range from 5 to 20% by weight and wherein the proportion of cereal straw is at or above 70% by weight, wherein the said proportion of cereal straw is calculated on the basis of the total quantity of cereal straw and of comminuted bast plant material containing bast plant fibres and shives, b) provision of at least one binding agent, in particular binding fibre, c) the provision of a minor quantity of comminuted bast plant material containing bast plant fibres and shives from the bast plant providing the bast plant fibres, wherein preferably the bast plant fibres and shives are at least partially bonded to one another, wherein the proportion of comminuted bast plant material is in the range from 2 to 20% by weight. %wherein the said proportion of comminuted bast plant material is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives, wherein the comminuted bast plant material containing plant fibers and shives mainly comprises plant fibers and / or shives with an average length in the range of 2 to 15 cm, d) producing a first material layer from the comminuted bast plant material containing bast plant fibers and shives in a first feed device, e) optionally producing at least one further, second material layer from the cereal straw according to a) in a further, second feed device, f) optionally mixing the first and / or second material layer and / or the cereal straw according to a) with at least one flame retardant, at least one hydrophobic agent and / or at least one biocide,in particular, applying an aqueous system containing at least one flame retardant, at least one hydrophobicizing agent and / or at least one biocide to the material layers from the top side, g) mixing the comminuted bast plant material containing bast plant fibers and shives with the cereal straw according to a) and / or e) and the at least one binder according to b), in particular the at least one binder fiber, in particular in an air stream, h) separating dust and / or foreign particles from the resulting mixture, in particular by means of at least one cyclone separator and / or condenser, in particular a condenser, i) optionally intermediate storage of the mixture obtained after step g) or h), j) discharging the mixture onto a conveyor belt to form a fiber web, k) treating the fiber web with at least one flame retardant, at least one hydrophobicizing agent and / or at least one biocide,in particular applying an aqueous system containing at least one flame retardant, at least one hydrophobicizing agent and / or at least one biocide to the fiber web from the top side, l) forming a pre-web by means of at least one first web former, in particular equipped with needles or pins, for example an aerodynamic web former, containing at least one needle roller or a drum, and / or by means of at least one web spreader, in particular comprising or consisting of at least one pin roller, wherein the mixture is preferably fed to the web former or web spreader by means of a first transport unit, in particular comprising at least one pair of rollers comprising an upper and lower roller or an upper roller and a trough table, m) optionally treating the pre-web with at least one flame retardant, at least one hydrophobicizing agent and / or at least one biocide,in particular, applying an aqueous system containing at least one flame retardant, at least one hydrophobicizing agent and / or at least one biocide to the pre-woven fabric from the top and / or bottom side, n) optionally applying, in particular sprinkling the pre-woven fabric, at least one particulate binder, in particular in the form of powder, granules or fibers or any mixture thereof, o) forming a nonwoven fabric from the pre-woven fabric according to step l), m) or n) by means of a second, in particular aerodynamic, nonwoven fabric former, in particular containing a drum, in particular equipped with a sawtooth wire and / or a pin roller, wherein the pre-woven fabric is preferably fed to the second nonwoven fabric former, in particular the drum, by means of a second transport unit containing at least one pair of upper and lower rollers or containing an upper roller and a feed table,p) optionally treating this nonwoven fabric with at least one flame retardant, at least one hydrophobicizing agent and / or at least one biocide, in particular applying an aqueous system containing at least one flame retardant, at least one hydrophobicizing agent and / or at least one biocide to the nonwoven fabric from the top and / or bottom side; q) optionally applying steam to the nonwoven fabric, in particular if a particulate binder, preferably in powder form, is added in step n); r) activating the binder by treating the nonwoven fabric obtained according to step o), p) or q) with heat for the purpose of thermobonding the binder, in particular the binding fibers, and optionally applying pressure to the nonwoven fabric simultaneously or at a later time; s) optionally calendering the nonwoven fabric obtained according to step q) or r); t) if a heat treatment has taken place in step q), r) and / or s),Cooling the nonwoven fabric solidified according to step q, r) and / or s) and optionally applying pressure and u) separating the solidified nonwoven fabric into fiber materials, in particular nonwoven fiber mats or nonwoven fiber boards, e.g. insulation mats.

[0023] Cereal straw within the meaning of the invention is threshed, dry stalks and leaves of cereals. In an expedient embodiment, this cereal straw is initially provided in a form pressed into bales. During processing, e.g. threshing cereal straw, and in particular also during pressing into bales, cereal straw is regularly bent, torn and / or cut, i.e. at least partially pre-shredded. Cereal straw is therefore at least partially pre-shredded plant material, even though an explicit shredding step has not taken place. The cereal straw can preferably be selected from the group consisting of wheat straw, barley straw, rye straw, spelt straw, oat straw, rice straw and any desired mixtures thereof. Wheat straw is preferably used for the methods according to the invention.

[0024] Cereal straw is characterized by its pronounced cuticle, particularly on its stalks. Plant cuticles are typically a waxy coating whose hydrophobic properties help reduce water loss. The cuticle is generally found on plant leaves and stems. The rhizodermis of plants, on the other hand, lacks a cuticle to prevent water and nutrient absorption. Especially in cereal straw, the cuticle creates a very smooth and even surface, preventing these components of the straw from sticking to each other or to other objects.

[0025] With the method according to the invention, it is no longer necessary for cereal straw to be subjected to a treatment step prior to processing into fiber materials, in particular nonwoven fiber mats or nonwoven fiber boards, in which it is converted into a state of greater flexibility compared to its state before this treatment step and / or in which the cuticle is completely or partially removed. Accordingly, cereal straw that has not been treated with heat and water, in particular has not been exposed to a wet steam, saturated steam and / or superheated steam atmosphere or has been boiled in an aqueous system, is preferably used for the method according to the invention. Wet steam is regularly formed, for example, by boiling water in a closed container in a dense steam atmosphere, with small water droplets being entrained by the steam during evaporation and are also present in the steam atmosphere.As soon as an equilibrium is established between the evaporation pressure of the water and the pressure of the water vapor during this process, the resulting steam is called saturated steam. If saturated steam separated from the (boiling) water is further heated, superheated steam is obtained. The methods according to the invention eliminate the need for treatment steps that could partially or completely remove the cuticle.

[0026] Accordingly, the method according to the invention preferably uses cereal straw that is provided essentially uncomminuted and chemically and thermally untreated. Uncomminuted cereal straw within the meaning of the present invention is defined as having been subjected to no further explicit comminution step, for example, by means of grinding units such as refiners, apart from the threshing process and any pressing process for producing bales, which may contribute to a certain degree of pre-comminution.

[0027] The cereal straw preferably has a residual moisture content in the range of 7 to 20 percent by weight and particularly preferably in the range of 10 to 15 percent by weight.

[0028] The method according to the invention regularly uses such comminuted cereal straw which has an average length, in particular absolute length, in the range up to 25 cm, e.g. from 0.5 to 25 cm or 4 to 25 cm, preferably in the range up to 20 cm, e.g. from 1 to 20 cm or 5 to 20 cm, and particularly preferably in the range up to 12 cm, e.g. from 1.5 to 12 cm or from 6 to 12 cm.

[0029] Particularly satisfactory results can also be achieved by increasing the proportion of cereal straw to or above 80 wt. % and preferably at or above 90 wt. % Additionally or alternatively, it can also be provided that the proportion of the crushed bast plant material is preferably in the range of 4 to 10 wt. %A major amount of cereal straw is present in the fiber materials according to the invention, in particular fiber mats or fiber mats, if these contain more than 50 wt. %of cereal straw. The above-mentioned proportion of cereal straw is calculated on the basis of the total amount of cereal straw and of comminuted bast plant material containing bast plant fibers and shives. In the same way, the proportion of comminuted bast plant material is determined on the basis of the total amount of this comminuted bast plant material and of cereal straw. This means that a minimum amount of comminuted bast plant material is present in the fiber materials according to the invention, in particular nonwoven fiber mats or nonwoven fiber boards, if these contain less than 50 percent by weight of comminuted bast plant material. Accordingly, the determination of the main and minimum amounts is fundamentally based on a comparison of the amount of cereal straw on the one hand and the amount of comminuted bast plant material on the other.

[0030] The comminuted bast plant material, in particular hemp and / or flax plant material, used in the method according to the invention is preferably subjected to a retting process, in particular a field retting, before the comminution step. In a particularly advantageous embodiment, the comminuted bast plant material, in particular hemp and / or flax plant material, has a degree of retting in the range of 1 to 8. The following scale is used to determine the degree of roasting: 1 = not roasted and 9 = roasting completed, with 1 - 3 = olive green to light green, 4 - 6 = light blond to beige with incipient fungal growth, 7 - 9 = ochre brown to dark brown with increasing fungal growth (according to IfPP (Information for Plant Production) Issue 7 / 1998, "Investigations into plant cultivation, harvesting technology and economic issues of the cultivation of fiber and grain hemp", State Institute for Plant Production Forchheim, ISSN 0937 - 6712, 7 / 1998).

[0031] In a further advantageous embodiment, the shredded bast plant material, in particular hemp and / or flax plant material, has a shives content of less than 50 wt. % , especially less than 45 wt. % , and particularly preferably less than 40 wt. % , each based on the total weight of the comminuted bast plant material. The average length, in particular the absolute length, of the fibers of the comminuted bast plant material, in particular flax plant material, is preferably in the range from 15 mm to 150 mm, in particular in the range from 30 mm to 130 mm, and particularly preferably in the range from 50 mm to 90 mm.

[0032] For the shredded bast plant material, preference is given to materials selected from the group consisting of hemp, jute, nettle, flax, kenaf, ramie and miscanthus or any mixtures thereof.

[0033] In a particularly expedient embodiment of the method according to the invention, the feed station comprises a weighing module, a device for loosening the cereal straw and / or bast plant material. By incorporating a weighing module, it can be ensured, preferably in an automated manner, that the resulting fiber materials, in particular nonwoven mats or nonwoven sheets, do not exhibit any significant variations in thickness, strength, and / or density. This would be detrimental to uniform, good thermal insulation as well as good stability. Fluctuations in thickness, strength, and / or density can also be significantly reduced further by providing a weighing module between the pre-fleece and fleece formation (steps m) and p)) to determine the amount of pre-fleece.By connecting the weighing module to a control unit, the amount of material to be fed to the second, particularly aerodynamic, web former per unit of time can be precisely adjusted.

[0034] Furthermore, it has proven preferable for many purposes to also provide a device for applying at least one flame retardant and / or at least one hydrophobic agent and / or at least one biocide to the bast plant material and / or the cereal straw for the inventive method. Devices of this type have proven particularly suitable for spraying the bast plant material and / or the cereal straw with an aqueous system containing at least one flame retardant and / or at least one hydrophobic agent and / or at least one biocide.Accordingly, sufficient flame retardancy for the fiber materials according to the invention, in particular nonwoven fiber mats or nonwoven fiber sheets, can be obtained by treating the fiber pile and / or the pre-woven fabric and / or the nonwoven fabric with at least one flame retardant, in particular with an aqueous system containing at least one flame retardant.

[0035] Suitable flame retardants can be selected from the group consisting of nitrogen-containing phosphates, in particular ammonium, melamine, or guanidine phosphate, aluminum phosphates, aluminum hydroxides, expandable graphite, borates, in particular ammonium, melamine, guanidine, potassium, or sodium borates, boric acid, boron phosphoric acid esters, pre-oxidized viscose fibers, pre-oxidized polyacrylonitrile fibers, carbon fibers, and rice hulls, or any mixtures thereof. Nitrogen-containing phosphates, in particular ammonium, melamine, or guanidine phosphates, aluminum phosphates, aluminum hydroxides, borates, in particular ammonium, melamine, guanidine, potassium, or sodium borates, boric acid, or boron phosphoric acid esters, or any mixtures thereof, can be very effectively incorporated in the form of aqueous systems, for example aqueous solutions, into the material present as a material layer, fiber web, pre-fleece, or nonwoven.

[0036] Furthermore, it is preferred that the first and / or second nonwoven former comprises a sieve drum that is subjected to, or can be subjected to, negative pressure for separating dust particles. This also allows conveying air to be extracted. The removal of dust and, if appropriate, conveying air contribute to further improved properties of the resulting fiber materials, for example, in terms of stability and strength.

[0037] Binder fibers (also called binder fibers) are preferably used as binders in the processes according to the invention. Thermoplastic mono- or multicomponent fibers can be used, with bicomponent fibers generally being preferred. Suitable bicomponent fibers can be based, for example, on polyesters, polylactides, and / or polyolefins. The binder can generally be used in the form of fibers, granules, or powder, or as any mixture of these binder forms. Thermoplastic binders are preferred. Binders in the form of binder fibers are preferably used for the production process according to the invention. The binder is generally based on thermoplastic polymers. These materials have a softening temperature, also called the glass transition temperature, above which they assume a deformable, melt-like consistency.Accordingly, the process known as thermobonding involves bonding the mixture of plant fibers and binders present in the pre-fleece or nonwoven fabric, resulting in a bond between individual fibers or fiber bundles via the temporarily softened binder. The thermoplastic binders solidify again upon cooling.

[0038] Phenolic resin fibers can also be used as binders. Other suitable binders, particularly for the production of MDF components from the fiber materials according to the invention, include urea-formaldehyde resins, melamine-urea-formaldehyde resins, phenol-formaldehyde resins, phenol-modified melamine-formaldehyde resins, tannin-formaldehyde resins, polymeric methanediphenyl diisocyanate, and / or phenolresorcinol resins.

[0039] Suitable binders for bonding nonwovens are known to those skilled in the art. This particularly applies to suitable binder fibers.

[0040] The step of activating the binder, in particular treating the nonwoven obtained according to one of steps m) or p) with heat for the purpose of thermobonding the binder, in particular the binding fibers, can, in a suitable embodiment, also comprise exposing the nonwoven to steam. Exposing the nonwoven to steam is also used, in particular, when a particulate binder, preferably in powder form, is used in step o). Exposing the nonwoven to steam can, in one embodiment, precede the activation step, in particular when exposing the nonwoven to steam is not sufficient for activating the binder. It then primarily serves to condition the nonwoven.

[0041] During activation, the binder forms a strong bond with the cereal straw and / or bast plant material. This is often achieved particularly effectively with thermoplastic binders through heat treatment. This takes advantage of the reversible softening behavior of thermoplastic materials.

[0042] The proportion of the binder, in particular the binding fiber, is preferably in the range of 2 to 25 wt. % , preferably in the range of 5 to 20 wt. % and particularly preferably in the range of 10 to 15 wt. % based on the total weight of the fiber material produced.

[0043] In one embodiment, the method according to the invention can be supplemented after step p) by the step of laminating the top and / or bottom side of the nonwoven with at least one cover nonwoven.

[0044] The method according to the invention also achieves the object underlying the invention particularly satisfactorily when the bast plant material containing plant fibers and shives mainly comprises plant fibers and / or shives with an average length, in particular absolute length, in the range from 3 to 12 cm and preferably in the range from 4 to 10 cm. Particularly suitable lengths of comminuted bast plant materials, in particular fibers / or shives, preferably fibers and shives, can also be obtained by the width of the cutting disks of the rotor shears or the rotor shredder being in the range from 4 cm to 15 cm, preferably in the range from 5 to 12 cm and particularly preferably in the range from 7 to 10 cm and / or by the diameter of the cutting disks being in the range from 300 mm to 900 mm, preferably in the range from 400 mm to 800 mm and particularly preferably in the range from 600 mm to 700 mm.The rotor shears or rotor shredders typically have two cutting shafts, particularly two that operate in opposite directions. Suitable rotor shears or rotor shredders are known to those skilled in the art, for example, from WO2013 / 167497.

[0045] In the case of the shredded bast plant materials containing plant fibers and shives, plant stems underlying them are preferably those with an average thickness, preferably maximum thickness, of up to 10 mm, preferably up to 6 mm and particularly preferably in the range of 3 mm to 5 mm.

[0046] According to a particularly advantageous embodiment, the desired length of bast plant fibers and shives can be achieved particularly reliably when using a guillotine cutter comprising a cutting blade that is movable or moved essentially transversely to the conveying direction of the bast plant material flow, in particular linearly. This method is particularly effective in cutting the bast plant fibers and shives to a predetermined average length without having to accept a particularly wide range of the resulting lengths.

[0047] A particularly homogeneous distribution of the components within the fiber materials obtained by the process according to the invention as well as a particularly plant-friendly and complication-free process sequence are achieved in particular by the fact that the plant stems underlying the comminuted bast plant material containing plant fibers and shives have an average thickness, preferably a maximum thickness, of up to 5 cm, preferably up to 4.5 cm and particularly preferably in the range from 0.2 cm to 3.5 cm before comminution.

[0048] For the process according to the invention, it is preferred to use such comminuted bast plant materials with a fiber content in the range of 10 to 90 wt. % , especially in the range of 20 to 60 wt. % and particularly preferably in the range of 40 to 60 wt. % , and / or a shives content in the range of 10 to 60 wt. %, especially in the range of 20 to 60 wt. % and particularly preferably in the range of 20 to 45 wt. % , each based on the total weight of the shredded bast plant material.

[0049] The object underlying the invention is further achieved by fiber materials, in particular fiber fleece mats or fiber fleece boards, in particular insulation mats, obtainable according to the process according to the invention, comprising cereal straw in an amount of 70 wt. % or more, calculated on the basis of the total weight of cereal straw and of comminuted bast plant material containing bast plant fibers and shives, and comminuted bast plant material containing bast plant fibers and shives, in particular from the bast plant providing the bast plant fibers, in an amount in the range of 2 to 20 wt. %, wherein the said proportion by weight of the comminuted bast plant material is calculated on the basis of the total weight of cereal straw and of comminuted bast plant material containing bast plant fibers and shives, wherein preferably the bast plant fibers and shives are at least partially bonded to one another, and at least one binder, in particular binding fiber, and optionally at least one flame retardant, hydrophobic agent and / or biocide, wherein the comminuted bast plant material containing plant fibers and shives mainly comprises plant fibers and / or shives with an average or absolute length in the range of 2 to 15 cm.

[0050] Preferred fiber materials according to the invention, in particular nonwoven fiber mats or nonwoven fiber boards, are characterized in that the proportion of cereal straw therein is preferably at or above 80 wt. %and particularly preferably at or above 90 wt. % wherein the said proportion by weight of cereal straw is calculated on the basis of the total weight of cereal straw and of comminuted bast plant material containing bast plant fibers and shives, and / or that the proportion of the comminuted bast plant material is preferably in the range of 4 to 10 wt. % wherein the said proportion by weight of the shredded bast plant material is calculated on the basis of the total weight of cereal straw and shredded bast plant material containing bast plant fibers and shives.

[0051] Suitable fiber materials, in particular nonwoven fiber mats or nonwoven fiber boards, are characterized by a density in the range greater than or equal to 15 kg / m 3 , preferably greater than or equal to 40 kg / m 3 , and particularly preferably in the range from 20 to 600 kg / m 3 . In a particularly expedient embodiment, the fiber materials according to the invention, in particular nonwoven fiber mats or nonwoven fiber boards, have a density in the range greater than or equal to 60 kg / m 3 and preferably greater than or equal to 150 kg / m 3 .

[0052] The fiber materials according to the invention, in particular fiber nonwoven mats or fiber nonwoven sheets, are also characterized in a preferred embodiment in that they essentially contain no straw shavings or that no straw shavings are added.

[0053] Also preferred are fiber materials, in particular nonwoven mats or nonwoven sheets, which essentially contain no cereal straw from which the cuticle has been partially or completely removed. Furthermore, fiber materials, in particular nonwoven mats or nonwoven sheets, which—alternatively or additionally—include essentially no refined cereal straw are also preferred.

[0054] Hearing-densified products can also be used in furniture construction, for example as a wall picture.

[0055] In a particularly useful embodiment, the fiber materials according to the invention are in the form of MDF boards, building insulation mats for heat and / or sound insulation, as a substrate for hydroponic systems or as furniture components.

[0056] The fiber materials according to the invention, in particular in the form of insulating mats or insulating boards, can preferably be used for sound and / or thermal insulation.

[0057] The present invention is based on the surprising discovery that cereal straw can be transported in uncomminuted form in conventional plants for the production of nonwoven mats if a small amount of comminuted bast plant material is added. While, for example, cereal straw as such sometimes cannot be transported at all via transport rollers or ladder belts, this is readily achieved if it is previously mixed with comminuted bast plant material. A further advantage of the method according to the invention is that the cereal straw as such can be processed cost-effectively into high-quality fiber materials, in particular nonwoven mats or nonwoven panels, without the cereal straw having to be subjected to prior comminution steps and / or chemical treatment to remove the cuticle.Also surprising is the high transport speed with which grain straw, especially essentially unshredded grain straw, can be processed into fiber materials, especially nonwoven mats or nonwoven panels, using thermobonding on conventional systems. The processes according to the invention produce fiber materials, especially nonwoven mats or nonwoven panels, in which the materials used are very homogeneously distributed. This results in very uniform insulation, both thermal and sound insulation. Accordingly, the density differences within the fiber materials, especially nonwoven mats or nonwoven panels, obtainable by the processes according to the invention are negligible or even nonexistent.

[0058] The products obtainable by this process therefore possess exceptional stability and can be used, for example, for exterior facade insulation. Furthermore, the process according to the invention allows for the flexible addition of both binders and flame retardants at various points in the process. This allows products for very specific applications to be manufactured in a targeted and reliable manner. Finally, the process according to the invention can also be used to obtain fiber materials, in particular nonwoven mats or nonwoven panels, with widely varying densities. Accordingly, the process according to the invention allows the production of fiber materials, in particular nonwoven mats or nonwoven panels, for both cavity insulation and facade insulation on one and the same system.

[0059] The features of the invention disclosed in the above description and in the claims may be essential for the realization of the invention in its various embodiments, both individually and in any combination.

Claims

1. Method for the production of fibrous materials, in particular fibrous web mats or fibrous web sheets, comprising a) Providing crop straw, wherein the crop straw has a residual moisture content in the range of 5 to 20% by weight and wherein the proportion of the crop straw is at or above 70% by weight, said proportion by weight of crop straw being calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives, b) Providing at least one binding agent, in particular binding fibre, c) Providing a reduced amount, relative to the amount of crop straw, of crushed bast plant material containing bast plant fibres and shives, wherein the proportion of the crushed bast plant material is in the range from 2 to 20 % by weight by weight, said proportion by weight of the crushed bast plant material being calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives, wherein the crushed bast plant material containing plant fibres and shives mainly comprises plant fibres and / or shives having an average or absolute length in the range of 2 to 15 cm, g) Mixing the crushed bast plant material containing bast plant fibres and shives according to c) with the crop straw according to a) and the at least one binding agent according to b), h) Separating dust and / or foreign particles from the resulting mixture, in particular by means of at least one cyclone separator and / or condenser, j) Discharging the mixture according to g) or h) onto a conveyor belt, forming a fibre blanket, n) optionally adding at least one, in particular particulate, binding agent to the mixture, q) Pressurizing the mixture with water vapour and / or r) Activating the binding agent and, optionally simultaneous or delayed pressurizing of the mixture, s) optionally calendering the mixture obtained according to step q) or r), t) if heat treatment has taken place in step q), r) and / or s), at least partial cooling of the mixture solidified in accordance with step q, r) and / or s) and, optionally, pressurizing, and u) Separating the solidified mixture into fibrous materials, in particular fibrous web mats or fibrous web sheets.

2. Method according to claim 1, further comprising after step c) the steps of d) Producing a first layer of material from the crushed bast plant material containing bast plant fibres and shives in a first feeding unit, e) Producing at least a second layer of material from the crop straw according to a) in a second feeding unit, f) Adding at least one flame retardant and / or one hydrophobising agent and / or one biocide to the first and / or second layer of material and / or the crop straw according to a), g) Mixing the crushed bast plant material containing bast plant fibres and shives with the crop straw according to a) and / or e) or f) and the at least one binding agent according to b).

3. Method according to any one of the preceding claims, further comprising after step j) the steps of: k) Treating the fibre blanket with at least a flame retardant and / or a water repellent and / or a biocide, m) Treating the nonwoven with at least a flame retardant and / or a water repellent and / or a biocide and / or p) Treating this fibrous web with at least a flame retardant and / or a water repellent and / or a biocide.

4. Method according to claim 3, further comprising after step g) and before step k) i) Intermediate storage of the mixture obtained after step g) or h) and j) Discharging the mixture according to i) onto a conveyor belt, forming a fibre blanket.

5. Method according to any one of the preceding claims, further comprising after step j) the steps of: l) Forming a nonwoven by means of at least one first fibrous web former and / or by means of at least one fibrous web spreader, n) optionally applying at least one, in particular particulate, binding agent to the nonwoven, o) Forming a fibrous web from the nonwoven according to step l) or n) by means of an aerodynamic fibrous web former, q) Applying water vapour to the fibrous web and / or r) Activating the binding agent by treating the fibrous web obtained in step o) or q) with heat for the purpose of thermobonding the binding agent and, optionally pressurizing the fibrous web simultaneously or with a time delay, s) Calendering the fibrous web obtained according to step q) or r), t) if heat treatment has taken place in step q), r) and / or s), cooling of the solidified fibrous web according to step q), r) and / or s) and, optionally pressurizing, and u) Separating the solidified fibrous web into fibrous nonwoven materials.

6. Method according to any one of the preceding claims, further comprising after step j) the steps of: o) Forming a fibrous web from the nonwoven according to step m) by means of an aerodynamic fibrous web former, r) Activating the binding agent by treating the fibrous web obtained according to step p) with heat for the purpose of thermobonding the binding agent and, optionally, pressurizing the fibrous web simultaneously or with a time delay, and / or t) if heat treatment has taken place in step q), r) and / or s), cooling the solidified fibrous web according to step q, r) and / or s) and pressurizing.

7. Method according to one of the preceding claims, characterised in that the crop straw is at least partially pre-crushed, in particular shortened in length, the crop straw is wheat straw, the shives originate from the bast plant supplying the bast plant fibres, the bast plant fibres and shives are at least partially connected to each other, the at least one binding agent is a binding fibre and / or the mixing in step g) takes place in air flow.

8. Method according to one of claims 4 to 7, characterised in that the first fibrous web former is an aerodynamic fibrous web former comprising at least one needle roller or a tambour, in step I) the mixture is fed to the fibrous web former or fibrous web spreader by means of a first transport unit comprising at least one pair of rollers consisting of an upper and lower roller or an upper roller and a feed table, in step o), the nonwoven is fed to the second fibrous web former, in particular a tambour, by means of a second transport unit comprising at least one pair of rollers consisting of an upper and lower roller or comprising an upper roller and a feed table, and / or the second fibrous web former contains a tambour equipped with a sawtooth wire and / or a pin roller.

9. Method according to one of the preceding claims, characterised in that the proportion of the crop straw is at or above 80% by weight and preferably at or above 90% by weight, said proportion of crop straw by weight being calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives, and / or in that the proportion of the crushed bast plant material is in the range from 4 to 10 % by weight, said proportion of the crushed bast plant material by weight being calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives, and / or that the crushed bast plant material comprises a fibre content in the range from 10 to 90 % by weight, in particular in the range from 20 to 60 % by weight and particularly preferaby in the range from 40 to 60 % by weight, and / or a shive content in the range from 10 to 60 % by weight, in particular in the range from 20 to 60 % by weight and particularly preferably in the range from 20 to 45 % by weight.

10. Method according to one of the preceding claims, characterised in that the crushed bast plant material containing plant fibres and shives mainly comprises plant fibres and / or shives with an average or absolute length in the range from 3 to 12 cm and preferably in the range from 4 to 10 cm and / or that the plant stems underlying the crushed bast plant material containing plant fibres and shives comprise an average or maximum thickness of up to 10 mm, preferably up to 6 mm and particularly preferably in the range from 3 mm to 5 mm.

11. Method according to one of the preceding claims, characterised in that the crop straw has a residual moisture content in the range of 7 to 20 % by weight and particularly preferably in the range of 10 to 15 % by weight.

12. Method according to one of the preceding claims, characterised in that the binding fibres are thermoplastic mono- or multicomponent fibres, in particular bicomponent fibres.

13. A fibrous web material, in particular a fibrous web mat or fibrous web sheet, obtainable by the method according to any one of the preceding claims, comprising crop straw in an amount of 70 % or more by weight, calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives, and crushed bast plant material containing bast plant fibres and shives, in particular from the bast plant providing the bast plant fibres, in an amount in the range from 2 to 20% by weight, said percentage by weight of the crushed bast plant material calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives and at least one binding agent and optionally at least a flame retardant, hydrophobising agent and / or biocide, wherein the crushed bast plant material containing plant fibres and shives mainly comprises plant fibres and / or shives having an average or absolute length in the range of 2 to 15 cm.

14. Fibrous material according to claim 13, characterised in that therein, the proportion of the crop straw is at or above 80 % by weight and particularly preferably at or above 90 % by weight, said proportion by weight of crop straw being calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives, and / or that the proportion of the crushed bast plant material is in the range from 4 to 10 % by weight, said proportion by weight of the crushed bast plant material being calculated on the basis of the total weight of crop straw and of crushed bast plant material containing bast plant fibres and shives, and / or that the proportion of the binding agent is in the range from 2 to 25 % by weight, preferably in the range from 5 to 20 % by weight and particularly preferably in the range from 10 to 15 % by weight, based on the total weight of the fibrous material produced, and / or that the crop straw comprises an average or absolute length in the range from 5 mm to 250 mm, preferably in the range from 10 to 200 mm and particularly preferably in the range from 20 mm to 120 mm.

15. Fibrous material according to claim 13 or 14, characterised in that the crop straw is wheat straw, the bast plant fibres and shives are at least partially connected together and / or the binding agent is a binding fibre.

16. Fibrous material according to any one of claims 13 to 15, characterised in that it is an MDF board, a building insulation mat for thermal and sound insulation, a substrate for hydroponic systems or a furniture component.

17. Fibrous material according to any one of claims 13 to 16, characterised in that it comprises a density in the range greater than or equal to 60 kg / m3, preferably greater than or equal to 100 kg / m3.

18. Use of the fibrous materials according to any one of claims 13 to 17 as or for the manufacture of MDF boards, building insulation mats for thermal and sound insulation, substrates for hydroponic systems or furniture components.