EP2864087B1 - Wood composite material with aerogels and corresponding production method and use - Google Patents

Description

The present invention relates to a wood composite material according to the preamble of claim 1. Furthermore, the invention relates to a method for producing a wood composite material as defined above. Finally, the invention relates to uses of aerogels in a wood-based panel. A corresponding wood composite material is for example from the EP 2 281 961 A1 known.

For the purposes of the present invention, a wood composite material is understood to mean a composite material which predominantly consists of wood material, that is to say which is made from wood material more than 50%. The rest of the composite material (less than 50%) is different material. Wood composites may, for example, at least one wood-based panel, in particular at least one chipboard, fiber and / or OSB board (OSB: oriented strand board, plate with aligned strands, that is special chips) have. Examples of wood composites are also WPC composites (WPC: wood plastic composites), cement-bonded particleboard or the like.

Wood material is understood to mean any form of wood, that is to say solid wood (uncrushed wood) or crushed wood, as well as fresh wood or wood recovered from recycling (recycled wood). Crushed wood also includes small boards in addition to boards and veneers Elements such as wood shavings, wooden strands, wood fibers, wood wool and wood flour. Wood chips are understood herein to mean particles of maximum size (length) of only a few millimeters, for example a maximum of 10 to 20 mm. Wood chips are used, for example, in the production of chipboard. This should be distinguished from wooden strands, which are elongated and relatively large wood particles. Wooden strands usually have a length of 100 to 200 mm and can be up to 1.5 mm thick. Wooden strands are used to make OSB boards. Another wood product to be distinguished is wood wool, which is so-called filament chips. Wood wool is usually used as a packing pad or as an insulating material, whereby the filament chips can be up to 500 mm long. Finally, wood fibers are known for the production of so-called fiberboard. These are elongated, axially arranged wood cells, which are usually obtained from small pieces of wood such as wood chips by steaming, cooking and chemical or mechanical digestion (defibration of the wood). For example, high-density fibreboard (HDF), medium-density fibreboard (MDF) or light fiberboard (LDF) can be produced from it.

Aerogels are highly porous solids that contain up to 99.98% of the volume of pores. There are several types of aerogels, with silicate-based ones being most common. Other materials, such as plastic or carbon based, are used in special cases. In principle, any metal oxide, polymer and other materials can be used as the starting point for the airgel synthesis by a sol-gel process. aerogels have a strong dendritic structure, ie a branching of particle chains with very many spaces in the form of open pores. These chains have contact points, so that ultimately results in the image of a stable, sponge-like network. Its aggregates have a fractal dimension, so they are self-similar to a certain extent. The pore size is in the nanometer range and the inner surfaces can be unusually large with up to 1000 square meters per gram. As a result, aerogels can be used inter alia as insulation or filter material. In addition, it is possible to store biologically active molecules, proteins or even whole cells. The fields of application of the aerogels will expand significantly with the discovery of further properties. Aerogels hold 15 entries in the Guinness Book of Material Properties records, including "best insulator" and "lightest solid" or least dense solid. Since especially silicate aerogels are comparatively well studied in their diversity, one can give quite accurate information for their spectrum. These properties are qualitatively as well as quantitatively quite similar in terms of quantity to those of the other aerogels, but with some specific peculiarities. The exact material properties depend on the desired use and therefore - depending on the starting material and the manufacturing process - can vary considerably. The high optical transparency, together with a refractive index of about 1.007 to 1.24 and a typical value of 1.02, makes aerogels interesting from an optical point of view. A silicate airgel appears milky blue against a dark background because the silica scatters the shorter wavelengths (that is, the blue portions of the white light) more than the longer wavelength radiation.

This effect can be observed in the form of Rayleigh scattering even in daylight in the earth's atmosphere. Despite its translucent appearance, the airgel feels like hard plastic foam. Because of this feature, they appear dull to transparent (see illustrations on the right) and therefore carry the nicknames "frozen smoke" or "blue smoke". The term silica airgel, however, refers to the structure rather than the chemical composition of the material. The latter corresponds approximately to SiO (OH) _y (OR) _z , with y and z as parameters dependent on the manufacturing process (source: http://en.wikipedia.org/wiki/Aerogel).

According to the DE 197 02 240 A1 are aerogels, especially those with porosities over 60% and densities less than 0.6 g / cm ³ , depending on the manufacturing process transparent, translucent or opaque and have an extremely low thermal conductivity. You will therefore find application as a thermal insulation material, such as. B. in the EP-A-0 171 722 described. Aerogels in the broad sense, ie in the sense of "gel with air as a dispersion medium", are prepared by drying a suitable gel. The term "airgel" in this sense covers aerogels in the narrower sense, xerogels and cryogels. Here, a dried gel is referred to as an airgel in the narrower sense, when the liquid of the gel at temperatures above the critical temperature and starting from pressures above the critical pressure is largely removed. On the other hand, if the liquid of the gel is removed undercritically, for example with the formation of a liquid-vapor boundary phase, then the resulting gel is often referred to as xerogel. When using the term aerogels in the present application is it concerns aerogels in the broader sense, ie in the sense of "gel with air as dispersing agent".

For the purposes of the present invention, aerogels are all those described above.

The DE 197 02 240 A1 describes multilayer composite materials, wherein at least one layer may contain aerogels and this layer may also contain up to 50 vol .-% fillers such as wood flour. In contrast to wood chips, strands and fibers, wood flour is very finely ground wood with a particle size of less than 0.1 mm (also known as wood dust). The aerogels are used to create a heat-insulating composite material that can be made as simple and in any shape and size.

The EP 2 281 961 A1 describes materials wherein aerogels in the form of particles are added to a fibrous material. The thread-like material may also be wood wool. Again, an insulating material to be produced in this way. The panels produced are so-called wood wool lightweight panels (see http://de.wikipedia.org/ wiki / wood wool-lightweight board), which are characterized by the geometry of the wood particles used (wood wool) fundamentally of chipboard, OSB boards and fiberboard differ. The binders used are different. Formaldehyde-based binders or those based on PMDI (Polymeric Diphenylmethanediisocyanate) are used for chipboards, OSB boards and fiberboards used, while wood wool lightweight panels are mineral bound. Details of the binder used makes the EP 2 281 961 A1 for the wood wool-based layers not, the mentioned binders refer exclusively to the use in a separate mineral layer.

Various additives and coating materials are known from the prior art in order to improve wood materials, in particular chipboard, OSB boards and fiberboard, also with additives or additives, with regard to the fire protection properties. In many cases so-called flame retardants are used. Flame retardants (or fire retardants) are substances which are intended to limit, slow down or prevent the spread of fires (see http://de.wikipedia.org/wiki/flammschutzmittel). The known flame retardants are mainly health or ecologically questionable or are unsatisfactory in their mode of action. Some of these additives also have a strong coloring power, so that parts of the installation are subjected to severe contamination, which disadvantageously increases the maintenance effort, in particular to be observed in the use of graphite as a fire retardant. The fire protection has a significant importance in building construction, in interior design, as well as in the application of wood materials in vehicle construction.

On this basis, it is an object of the present invention to improve the fire protection properties of wood-based materials.

The previously derived and indicated object is achieved according to a first teaching of the present invention by a wood composite material with the features of claim 1.

According to the invention, for the first time, aerogels are used in a wooden material made from a wood material in the form of compressed wood chips, strands and / or fibers, namely either inside the compressed wood material and / or in a separate coating on the compressed wood material, which will be described below is explained in more detail, a new material (wood composite material) is created, the thermal conductivity is greatly reduced. This is particularly advantageous for LDF boards, as these are widely used for Dämmzwecke. In this way, the fire protection properties of wood-based materials continue to be significantly improved.

"Pressed together" means that from a variety of accumulated to a so-called cake wood chips, strands or fibers in a press a pressed part is produced, for example, when using predominantly wood chips a so-called particle board, when using predominantly wood strands one OSB board or when using predominantly wood fibers a fiberboard, preferably an LDF board. It should be noted that both in the case that the said pressing member has aerogels in its interior and in the case that the pressing member is provided with an aerogels coating, this is a wood material body, in particular a wood-based panel, which in the latter case coated is.

The wood material used according to the invention may contain, in addition to wood shavings, strands and / or fibers, other wood material, as mentioned for example in the introductory paragraphs, or else cellulose material.

Preferably, the wood material is bound by adding a binder. But this is not absolutely necessary. The binders used in particular are the abovementioned formaldehyde-based binders or those based on PMDI.

• Gemäß einer weiteren Ausgestaltung ist vorgesehen, dass die Aerogele in dem Holzmaterial, insbesondere gleichmäßig, verteilt sind. Dabei kann der Anteil an Aerogelen zur Oberfläche des Holzverbundwerkstoffs bzw. Holzwerkstoffs zunehmen oder aber abnehmen.

In the following, various embodiments of the wood composite material body according to the invention are defined:

• According to a further embodiment, it is provided that the aerogels are distributed in the wood material, in particular evenly. The proportion of aerogels to the surface of the wood composite material or wood material may increase or decrease.

According to one embodiment, it is provided that the aerogels are incorporated into a separate layer (matrix), which is applied (laminated) to the wood material, in particular to a molded article produced from the wood material by compression, and which in particular is free of wood particles, wherein the Wood material or the molding is in particular free of aerogels. In the separate layer or matrix, the aerogels may also be bonded together by a binder. The binder may be the same binder as in the wood or molding. It should be mentioned again that too a molded body in which a separate layer has been applied with aerogels, as a wood material, in particular as a wood-based panel is to be regarded, namely as a coated wood material. The wood-based material or wood composite material according to the invention can also be provided on both sides with a separate layer containing such an aerogels.

According to a further embodiment, it is provided that the thickness of the separate layer containing the aerogels is smaller than the thickness of the compressed wood material or molded body.

According to the invention, the proportion of aerogels in the wood composite material is less than 50% by volume and preferably in a range between 1 and 30% by volume, more preferably in a range between 1 and 20% by volume.

Furthermore, it is provided according to the invention that the wood material of the wood composite material consists of more than 50% by volume, preferably more than 75% by volume, particularly preferably more than 90% by volume, of wood chips, with more than 50% preferably more than 75%, more preferably more than 90%, of the wood chips has a length of less than 50 mm, preferably a length in a range of 1 to 20 mm, particularly preferably a length in a range of 1 to 10 mm Another embodiment provides that the wood material of the wood composite material to more than 50 vol .-%, preferably more than 75 vol .-%, more preferably more than 90 vol .-% consists of wood chips, in particular more than 50%, preferably more than 75%, particularly preferably more than 90%, of the wood chips has a width of less than 10 mm, preferably of less than 5 mm, more preferably less than 2 mm, and / or a thickness of less than 1.5 mm, preferably less than 1.0 mm, more preferably less than 0.5 mm.

Additionally or alternatively, the invention provides that the wood material of the wood composite material to more than 50 vol .-%, preferably more than 75 vol .-%, more preferably more than 90 vol .-%, consists of wood strands, wherein more than 50 %, preferably more than 75%, particularly preferably more than 90%, of the wood strands has a width of more than 4.5 mm, preferably a width in a range of 5 to 60 mm, particularly preferably a width in a range of 10 to 50 mm. According to a further embodiment, it is provided that the wood material of the wood composite material to more than 50 vol .-%, preferably more than 75 vol .-%, more preferably more than 90 vol .-%, consists of wood strands, in particular more than 50%, preferably more than 75%, particularly preferably more than 90%, of the wood strands has a length in a range from 80 to 300 mm, preferably in a range from 90 to 250 mm, particularly preferably in a range from 100 to 200 mm, and / or have a thickness of more than 0.5 mm, preferably in a range of 0.6 to 1.8 mm, more preferably in a range of 0.6 to 1.5 mm.

According to the invention, it is additionally or alternatively provided that the wood material of the wood composite material consists of more than 50% by volume, preferably more than 75% by volume, particularly preferably more than 90% by volume, of wood fibers.

According to a further embodiment, it is provided that the aerogels (in the compressed wood material, that is to say in the pressed part, and / or in the separate layer) are in the form of granules, the mean grain size of the aerogels in the wood composite material being in a range of 0, 3 to 4 mm, preferably in a range of 0.5 to 2.5 mm, more preferably in a range of 0.8 to 1.8 mm, and / or the average apparent density in a range of 0.001 to 0.6 g / cm ³ , preferably in a range from 0.01 to 0.3 g / cm ³ , particularly preferably in a range from 0.05 to 0.1 g / cm ³ . In the event that the areogels are part of the wood material in a separate layer, the separate layer may have a thickness which is at least as large as the largest size of the aerogels used in the separate layer. If, for example, granules of aerogels whose particle size distribution ranges from 0.3 to 4 mm are present in the separate layer, the thickness of the separate layer is preferably at least 4 mm. If, for example, a granulate is used in which the maximum grain size of the aerogels is 2 mm, the thickness of the separate layer can be at least 2 mm. But there are also other thicknesses conceivable. Thus, the thickness of the separate layer may be in a range of 1 to 20 mm, preferably in a range of 1 to 10 mm, particularly preferably in a range of 2 to 8 mm.

According to yet another embodiment, it is provided that the proportion of the wood material in the form of wood chips, strands and / or fibers (ie the proportion of the wood material which is present in the wood composite in the form of wood chips, strands and / or fibers) is at least 50% and preferably in a range of 50 to 80% by volume, especially preferably in a range of 50 to 70% by volume. In principle, other wood material may also be provided in the wood composite material, which is then not covered by the said portion.

Finally, according to another embodiment, the wood material of the wood composite material is more than 50% by volume, preferably more than 75% by volume, particularly preferably more than 90% by volume, of wood particles selected from the group containing wood shavings, wood strands and wood fibers. In other words, different types of wood particles from the group mentioned can also occur or be present in the wood composite material according to the invention. Thus, it is conceivable that the wood material in the wood composite material is formed by both wood shavings and wood strands and / or wood fibers, or both wood strands and wood fibers. All three types of wood particles mentioned, namely wood chips, wood strands and wood fibers, can also occur simultaneously in the wood material or form the wood material.

If different wood particle types from the aforementioned group are provided, these may be provided as a mixture and / or in separate layers. That is, for example, if both wood chips and wood strands are provided, at least one layer of the wood composite material may have a mixture of wood chips and wood strands (although other types of wood particles may additionally be included in the mixture). Additionally or alternatively, it is also conceivable that in the case that the wood composite material has both wood chips and wood strands, at least one layer no wood shavings or no wooden strands or at least one layer has no wood shavings and another layer has no wooden strands. For example, if both wood chips and wood fibers provided, at least one layer of the wood composite material may have a mixture of wood chips and wood fibers (in addition, other types of wood particles may be included in the mixture). Additionally or alternatively, it is also conceivable that in the case that the wood composite material has both wood chips and wood fibers, at least one layer has no wood chips or wood fibers or at least one layer has no wood chips and another layer has no wood fibers. If, for example, both wood strands and wood fibers are provided, at least one layer of the wood composite material may comprise a mixture of wood strands and wood fibers (although other types of wood particles may additionally be present in the mixture). Additionally or alternatively, however, it is also conceivable that in the case that the wood composite material has both wood strands and wood fibers, at least one layer has no wood strands or no wood fibers or at least one layer has no wood strands and another layer has no wood fibers.

The statements made in the preceding paragraphs concerning the composition of the wood material do not exclude that in addition to wood shavings and / or wood strands and / or wood fibers, other types of wood material are provided in the wood composite material, for example the types of wood material such as wood wool, wood flour mentioned in the introduction Etc.

The previously defined wood composite material may also have an additional coating, which is either applied directly or connected to it by means of an adhesive. A directly applied coating is for example a lacquer. A coating applied by means of an adhesive is, for example, a film.

A wood composite material as defined above can, for example, also be used as part of a sandwich panel, for example as a cover layer of the sandwich panel.

The previously derived and indicated object is achieved according to a second teaching of the present invention by a method having the features of claim 10. The aerogels form together with the wood material, the wood composite material.

• Gemäß einer Ausgestaltung ist vorgesehen, dass die Aerogele zunächst in einem ersten Schritt mit dem (noch nicht verpressten) Holzmaterial und gegebenenfalls einem Bindemittel zu einem Gemisch vermengt werden, anschließend in einem zweiten Schritt das Gemisch auf einen Träger gestreut wird und wiederum anschließend in einem dritten Schritt das auf dem Träger befindliche (noch nicht verpresste) Material verpresst wird. Bei dem Träger kann es sich beispielsweise um ein Transportband handeln.

Various embodiments of the method according to the invention are now defined below:

• According to one embodiment, it is provided that the aerogels are first mixed in a first step with the (not yet compressed) wood material and optionally a binder to a mixture, then in a second step the mixture is sprinkled on a support and then in a third Step that is pressed on the carrier (not yet pressed) material is pressed. The carrier may be, for example, a conveyor belt.

According to a further embodiment, it is provided that the carrier is sprinkled before pressing with several layers with (not yet pressed) wood material, of which contains at least one aerogels. The layer containing the aerogels may be at the bottom, at the top or in the middle. It is also possible to provide layers containing a plurality of aerogels which may be adjacent to one another or spaced from one another in the layer structure.

According to a further embodiment, it is provided that the wood material is provided as a shaped body, in particular plate-shaped molded body, of wood chips, strands and / or fibers pressed together, and the aerogels are applied to the shaped body as a separate layer (matrix) into which they are incorporated applied (laminated), wherein the molding is in particular free of aerogels. In principle, however, it is also conceivable that the shaped body likewise has aerogels.

According to a further embodiment it is provided that the (not yet compressed) wood material first in a first step, in particular without the addition of aerogels (but also the addition of aerogels is conceivable), is scattered on a support, and then in a second step the aerogels are applied to the material on the support (not yet pressed) as a separate layer into which they are bound.

According to a further embodiment, it is provided that the support is sprinkled before pressing with one or more layers with (not yet pressed) wood material, of which contains at least one aerogels. It can be the Aerogels containing layer to be bottom, top or center. It is also possible to provide layers containing a plurality of aerogels which may be adjacent to one another or spaced from one another in the layer structure.

According to a further embodiment, it is provided that the pressing is carried out in a double-belt press or calendering press. The average compacting pressure during pressing may range from 1 to 50 kg / cm ² , preferably from 5 to 50 kg / cm ² , more preferably from 10 to 40 kg / cm ² . The average pressing temperature during pressing may be in the range from 100 ° to 300 ° C., preferably in a range from 150 ° to 250 ° C., particularly preferably in a range from 180 ° to 220 ° C. In this case, "average" pressing pressure and "average" pressing temperature mean the pressing pressure averaged over the length of the pressing device or the pressing temperature averaged over the length of the pressing device. The pressing speed (pressing factor) may be in a range of 1 to 20 s / mm, preferably in a range of 2.5 to 15 s / mm, more preferably in a range of 3.5 to 10 s / mm (Note: because the pressing speed depends on the plate thickness, it is referred to this and expressed by the so-called pressing factor in seconds per mm plate thickness (s / mm)).

The present invention also relates to the use of aerogels in (ie in the interior or as a cover layer) of a wood-based panel, in particular chip, OSB or fiberboard, in particular in a previously defined Wood composite material to improve fire resistance.

Finally, the invention also relates to the use of aerogels in (ie in the interior or as a cover layer) of a wood-based panel, in particular chip, OSB or fiberboard, preferably LDF board, in particular in a wood composite material as defined above, to reduce the heat transfer.

Fig. 1a)

ein erstes Ausführungsbeispiel eines erfindungsgemäßen Herstellungsverfahrens,

Fig. 1b)

ein zweites Ausführungsbeispiel eines erfindungsgemäßen Herstellungsverfahrens,

Fig. 2a)

ein drittes Ausführungsbeispiel eines erfindungsgemäßen Herstellungsverfahrens und

Fig. 2b)

ein viertes Ausführungsbeispiel eines erfindungsgemäßen Herstellungsverfahrens.

There are now a variety of ways to design and further develop the wood composite material according to the invention and the inventive method. For this purpose, reference is made, on the one hand, to the claims subordinate to patent claim 1, and, on the other hand, to the description of exemplary embodiments in conjunction with the drawing. In the drawing shows:

Fig. 1a)

A first embodiment of a manufacturing method according to the invention,

Fig. 1b)

A second embodiment of a manufacturing method according to the invention,

Fig. 2a)

a third embodiment of a manufacturing method according to the invention and

Fig. 2b)

A fourth embodiment of a manufacturing method according to the invention.

With all procedures, which in the FIGS. 1a ) 1b ) 2a) and 2b ), a wood composite material 1 (a Wood material board), the wood material 2 in the form of wood chips, strands and / or fibers and aerogels 4 has.

Basically, the individual manufacturing processes differ, among others, as follows.

According to Fig. 1a ) it is provided that the aerogels 4 are first mixed in a first step with the wood material 2 to a mixture 5, then in a second step, the mixture 5 is scattered on a support 6 and in turn in a third step, the on the support. 6 befindliches material 7 is pressed.

In Fig. 1b ), several layers 7.1, 7.2 and 7.3 are sprinkled on the carrier 6 before pressing, of which the lower layer 7.1 and the upper layer 7.3 has aerogels 4. The middle layer 7.2 is free of aerogels.

In the manufacturing method according to Fig. 2a ) It is provided that the wood material 2 is provided as a plate-shaped body 3 of compressed wood chips, strands and / or fibers and aerogels 4 are applied as a separate layer 1.1, in which they are integrated, on the molding 3, wherein the Shaped body 3 is in particular free of aerogels 4. The thickness d of the separate layer 1.1 is smaller than the thickness D of the wood material 2.

In the embodiment in Fig. 2b ) is finally provided that the wood material 2 is first scattered in a first step, in particular without the addition of aerogels 4, on a support 6, and then in a second step the material 7 located on the support 6, the aerogels 4 as a separate layer 1.1, in which they are involved, are applied. Again, the thickness d of the separate layer 1.1 is smaller than the thickness D of the wood material. 2

In the embodiments in the FIGS. 1a ) 1b ) and 2 B ) is provided as a pressing device 8 a double belt press. Alternatively, a calender press can be used. In the embodiment in Fig. 2a ), the molded body 3 has been prepared in a comparable manner, which is not shown here. The illustrated roller 9 serves in Fig. 2a ) not as part of a pressing device, but only for pressing (laminating) the separate layer 1.1.

In the aforementioned separate layer 1.1 is a matrix, for example in the form of a plastic film or mat, in which aerogels are embedded in the form of granules.

Claims (15)

1. A wood composite material (1), in particular a wood composite material (1) in the form of a panel, containing wood material, wherein wood material is understood to mean any form of wood, wherein the proportion of aerogels (4) in the wood composite material (1) is less than 50 vol. %, characterised in that the wood material (2) is provided in the form of compressed wood chips, strands and/or fibres, and in that the wood material (2) of the wood composite material (1) consists to an extent of more than 50 vol. % of wood chips of which more than 50 % have a length of less than 50 mm, and/or wood strands of which more than 50 % have a width of more than 4,5 mm, and/or wood fibres.
2. The wood composite material (1) according to claim 1, characterised in that the aerogels (4) are distributed, in particular uniformly, in the wood material (2), or the aerogels (4) are incorporated in a separate layer (1.1) which is applied onto the wood material (2), wherein the wood material (2) is in particular free from aerogels (4), wherein in particular the thickness (d) of the separate layer (1.1) containing the aerogels (4) is smaller than the thickness (D) of the compressed wood material (2) or shaped product (3).
3. The wood composite material (1) according to any one of the preceding claims, characterised in that the proportion of aerogels (4) in the wood composite material (1) lies in a range between 1 and 30 vol. %, preferably in a range between 1 and 20 vol. %.
4. The wood composite material (1) according to any one of the preceding claims, characterised in that more than 75 %, preferably more than 90 %, of the wood chips have a length of less than 50 mm, preferably a length in a range from 1 to 20 mm, particularly preferably a length in a range from 1 to 10 mm.
5. The wood composite material (1) according to any one of the preceding claims, characterised in that more than 75 %, preferably more than 90 %, of the wood strands have a width of more than 4,5 mm, preferably a width in a range from 5 to 60 mm, particularly preferably a width in a range from 10 to 50 mm.
6. The wood composite material (1) according to any one of the preceding claims, characterised in that the wood material (2) of the wood composite material (1) consists to an extent of more than 75 vol. %, preferably more than 90 vol. %, of wood chips and/or wood strands, and/or wood fibres.
7. The wood composite material (1) according to any one of the preceding claims, characterised in that the aerogels (4) are present in the form of granulate, wherein the mean grain size of the aerogels (4) in the wood composite material (1) lies in a range from 0,3 to 4 mm, preferably in a range from 0,5 to 2,5 mm, particularly preferably in a range from 0,8 to 1,8 mm, and/or the mean raw density lies in a range from 0,001 to 0,6 g/cm³, preferably in a range from 0,01 to 0,3 g/cm³, particularly preferably in a range from 0,05 to 0,1 g/cm³.
8. The wood composite material (1) according to any one of the preceding claims, characterised in that the proportion of wood material (2) in the form of wood chips, strands and/or fibres is at least 50 % and preferably lies in a range from 50 to 80 vol. %, particularly preferably in a range from 50 to 70 vol. %.
9. The wood composite material (1) according to any one of the preceding claims, characterised in that the wood material (2) of the wood composite material (1) consists to an extent of more than 50 vol. %, preferably more than 75 vol. %, particularly preferably more than 90 vol. %, of wood particles selected from the group containing wood chips, wood strands and wood fibres.
10. A method for producing a wood composite material (1) according to any one of the preceding claims with use of wood material, wherein a wood material is understood to mean any form of wood, wherein the aerogels (4) are bonded to a wood material in the form of wood chips, strands and/or fibres and the proportion of aerogels (4) is selected such that it is less than 50 vol. % in the wood composite material (1).
11. The method according to claim 10, characterised in that the aerogels (4) are first blended in a first step with the wood material (2) to form a mixture (5), then, in a second step, the mixture (5) is scattered onto a carrier (6), and then, in a third step, the material (7) disposed on the carrier (6) is compressed, wherein in particular a plurality of layers (7.1, 7.2, 7.3) comprising wood material (2) are scattered onto the carrier (6) prior to compression, at least one of which layers contains aerogels (4).
12. The method according to claim 10, characterised in that the wood material (2) is provided as a shaped product (3), in particular a shaped product (3) in the form of a panel, formed of compressed wood chips, strands and/or fibres, and the aerogels (4) are applied to the shaped product (3) as a separate layer (1.1) in which they are incorporated, wherein the shaped product (3) is in particular free from aerogels (4).
13. The method according to claim 10, characterised in that the wood material (2) is first scattered, in a first step, onto a carrier (6), in particular without addition of aerogels (4), and then, in a second step, the aerogels (4) are applied, as a separate layer (1.1) in which they are incorporated, onto the material (7) disposed on the carrier (6), wherein in particular one or more layers comprising wood material (2) is/are scattered onto the carrier (6) prior to compression, at least one of which layers contains aerogels (4).
14. Use of aerogels (4) in a wood-based material panel according to any one of claims 1 to 9, in particular chipboard or OSB board, to improve the fire resistance.
15. Use of aerogels (4) in a wood-based material panel according to any one of claims 1 to 9, in particular fibreboard, preferably LDF board, to reduce the heat transfer.

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