EP2546038A1 - Method of reducing the emissions of fleeting organic compounds in wooden materials - Google Patents

Abstract

Manufacture of optionally-coated timber products involves contacting lignocellulose-containing reduction products with adhesive, and compressing the mixture under heat treatment such that emission of volatile organic compounds or very volatile organic compounds, preferably (un)saturated aldehyde is prevented. The mixture contains additive chosen from alcohols, acid and/or antioxidant.

Description

The present application relates to processes for the preparation or treatment of optionally coated wood materials from lignocellulose, in particular chipboard, fiberboard or OSB boards but also plywood and solid wood, these wood materials in the production to avoid or reduce the emission of volatile organic compounds but also very volatile organic compounds, such as unsaturated or saturated aldehydes, with at least one additive is treated. More specifically, these additives are alcohols, which are optionally introduced in combination with catalytically effective amounts of acid. Alternatively or additionally, a treatment with suitable antioxidants can take place, this being preferably introduced with the aid of a carrier material. In a further aspect, the present application is directed to the use of alcohols, optionally in combination with catalytically effective amounts of acid and / or antioxidant, as additives for reducing the emission of VOCs, particularly unsaturated and saturated aldehydes, in manufacture and use of wood-based materials made of lignocellulose. Finally, the application is directed to obtainable by the process according to the invention wood materials or by using the additive produced wood materials with reduced emission of volatile organic compounds.

State of the art

The emission of volatile organic compounds (VOC) from wood-based materials (HWS) represents a serious problem in terms of the increasing use of woody products in the rooms. In addition to saturated and unsaturated aldehydes, volatile organic compounds include all volatile organic compounds, their retention time in the gas chromatograph between C6 (hexane) and C16 (hexadecane). VOCs are not a homogeneous class of substances but a smorgasbord of compounds. These include organic acids, saturated and unsaturated aldehydes, alcohols, carboxylic acids, terpenes, aliphatic and aromatic hydrocarbons and many more. Furthermore, there are the very volatile organic compounds (VVOC), under which e.g. Formaldehyde or formic acid, which also occur in the production of wood-based materials. The emission of these volatile and highly volatile wood constituents or components of wood product adhesives, including solid wood and wood-based panels, is becoming more and more of a problem due to tightening limits or increasing end-user awareness.

The term aldehydes as used herein includes saturated and unsaturated aldehydes as falling within the classes of volatile organic compounds or very volatile organic compounds.

To avoid the emission of these volatile organic compounds, various proposals have hitherto been made. So will in the EP 185 231 described that oxidizing agents are used to reduce emissions. Furthermore, various proposals have been proposed to reduce the emission of formaldehyde. Due to the heterogeneity of the volatile organic compounds, however, a particularly permanent avoidance or reduction of the emission of these compounds is desired. A transformation of the heterogeneous class of VOCs, which are partially toxic, however, a single chemical reaction is difficult.

A reduction of volatile organic compounds and very volatile organic compounds from the wood, in particular volatile wood constituents during production but also in use, is therefore still desirable. It should be noted that the emission of VOCs and also of WOCs does not occur during the manufacturing process, but also during use by decomposition of wood constituents, as a result of the chemical degradation of the adhesives used. However, VOC emissions are mainly due to wood-related releases of so-called primary emissions of volatile wood constituents, such as terpenes, or chemical degradation products, such as acetic acid, and so-called secondary or tertiary emissions, e.g. higher aldehydes, such as pentanal or higher carboxylic acids. These decomposition products are caused by long-lasting oxidation processes of wood constituents, such as fatty acids, but also lignin, cellulose and hemicellulose.

Typical conversion products that occur inter alia during storage and processing of the wood or crushed products include pentanal and hexanal. Particularly critical compounds in the heterogeneous group of VOC and WOC are the saturated and unsaturated aldehydes. These are not only toxic, but also carcinogenic in part. Furthermore, they are classified as critical by the olfactory aspect. The aldehydes are formed, inter alia, in the production of wood-based materials, as shown above, and are released in particular by OSB plates delayed by fragmentation of unsaturated fatty acids and due to the use of aldehyde-containing adhesives. Especially for OSB panels in the structural area this is a great disadvantage, since in this application, the OSB panels have no emission-reducing coating and in large quantities, especially as the area of the plate based on the total cubic meters of the room or building is installed.

Similar problems with aldehyde emission can occur with the use of light wood materials, such as lightweight and superlight MDF for thermal insulation. These emit more aldehydes, e.g. cyclic aldehydes. Problems arise both by the amount of emission and by the toxicity of the compounds.

As already stated, volatile organic compounds, such as aldehydes, are also released by the adhesives used during production or subsequently during use. Adhesives such as those currently being used in the manufacture of wood-based materials such as OSB boards, dense fiberboard, etc. include aminoplast adhesives such as urea-formaldehyde (UF) adhesives, melamine-urea-phenol-formaldehyde adhesives (MUPF adhesives) or melamine-urea-formaldehyde adhesives (MUF adhesives). Other adhesives typically used in wood-based materials include diisocyanate-based adhesives (PMDI), polyurethane adhesives, phenol-formaldehyde (PF) adhesives, and / or tannin-formaldehyde (TF) adhesives, or mixtures thereof. In the field of fibreboard mainly aminoplast adhesives are used. Here a release of the aldehydes and other VOCs and VVOCs takes place both during the production of wood-based materials as well as after their production or in their application. In fiberboard production, e.g. in the thermomechanical treatment of the lignocellulosic materials to a partial chemical degradation of the wood come. The resulting volatile organic compounds and very volatile organic compounds, such as aldehydes and acids, then emit during the later manufacturing process or later use of the wood-based materials produced. They can also have a negative influence on the bond strength and thus adversely affect the properties of the produced wood materials.

Many approaches have already been taken, these emissions issues of volatile organic compounds, including aldehydes. So will in the EP 1 852 231 proposed the use of various additives. There is provided, inter alia, the use of maleic anhydride or similar compounds. The use of reducing or oxidizing agents is also known. Furthermore, an increase in the pH is proposed, for example by addition of alkali metal hydroxides.

From the WO 2006/032267 are known methods for the reduction of unsaturated aldehydes in fatty acid-containing woods. The fatty acid ester contained in the wood is split, inhibited or oxidized. For this purpose, the use of antioxidants, alkaline compounds or oxidizing agents is generally proposed. However, these additives are treated before drying the freshly cut solid wood or before or during the production of the wood particles. Adding this after or during the contacting of the comminution products with adhesives and in particular after pressing the wood-based materials is not provided or is considered to be disadvantageous.

There is therefore still a need for methods for reducing the emission of volatile organic compounds but also very volatile organic compounds, in particular aldehydes and organic acids, in particular degradation products of fatty acids from wood-based materials.

The present invention is based on the object, if appropriate coated wood materials of lignocellulose, especially particleboard, fiberboard or OSB boards but also plywood and solid wood to provide an improved reduction or prevention of emissions of volatile organic compounds (VOC) and very volatile organic Compounds (VVOC). The purpose of this is the emission of this volatile or volatile organic compounds, including saturated and unsaturated aldehydes, are significantly reduced both in production and in later use. Furthermore, the odor nuisance resulting from these volatile or very volatile organic compounds should also be reduced. In particular, it should be taken into account that no substances which disturb the production process of these wood-based materials are used or generated. Also, an important aspect is that the manufacturing cost of wood-based materials is not significantly increased. In this case, the agents used themselves must not be toxic or carcinogenic, but should as far as possible either react with the heterogeneous classes of volatile organic substances or very volatile organic compounds or prevent their formation from constituents of the wood-based materials.

Description of the invention

The object of the present invention is achieved in that certain additives are added at certain times in the inventive method for producing or processing the wood materials from lignocellulose. These additives are alcohols, optionally in combination with a catalytically effective amount of acid and / or certain antioxidants.

1. a) Inkontaktbringen von Lignozellulose-haltigen Zerkleinerungsprodukten mit Klebstoffen;
2. b) Verpressen der Mischung aus a) unter Wärmebehandlung,

dadurch gekennzeichnet, dass bei dem Inkontaktbringen gemäß Schritt a) und/oder zwischen dem Inkontaktbringen gemäß Schritt a) und dem Verpressen gemäß Schritt b) und/oder nach dem Verpressen gemäß Schritt b) zur Vermeidung der Emission von flüchtigen organischen Verbindungen (VOC) und sehr flüchtigen organischen Verbindungen (WOC), insbesondere ungesättigter oder gesättigter Aldehyde, weiterhin mindestens ein Additiv ausgewählt aus Alkoholen, gegebenenfalls in Kombination mit einer katalytisch wirksamen Menge an Säure, und/oder einem Antioxidationsmittel als Additiv eingetragen wird.That is, in a first aspect, the present application is directed to a process for the preparation of optionally coated wood materials from lignocellulose, in particular chipboard, fiberboard, OSB boards or plywood comprising the steps:

1. a) contacting lignocellulose-containing comminution products with adhesives;
2. b) pressing the mixture from a) under heat treatment,

characterized in that in the contacting according to step a) and / or between the contacting according to step a) and the compression according to step b) and / or after the compression according to step b) to avoid the emission of volatile organic compounds (VOC) and very volatile organic compounds (WOC), in particular unsaturated or saturated aldehydes, further at least one additive selected from alcohols, optionally in combination with a catalytically effective amount of acid, and / or an antioxidant is added as an additive.

In contrast to most of the processes used so far, not only are chemical modifications of the emitting VOCs and VVOCs aimed for, but above all they prevent conversion or degradation of the starting materials in the wood. In other words, the additives used according to the invention prevent degradation of the fatty acids or fatty acid esters. Furthermore, aldehydes optionally formed by conversion reactions are converted to corresponding non-emitting compounds.

The compounds obtained by the reaction are such that they are no longer volatile and thus no longer contribute to the VOC and VVOC emissions or aldehyde emissions or the toxicity of the resulting compounds is significantly reduced. In particular, the emission is also after production, i. in daily use, significantly reduced.

1. a) Inkontaktbringen von Lignozellulose-haltigen Zerkleinerungsprodukten mit Klebstoffen;
2. b) Verpressen der Mischung aus a) unter Wärmebehandlung,

dadurch gekennzeichnet, dass die Additive auf einem Trägermaterial vorliegen und dieses Additiv-aufweisende Trägermaterial zwischen Schritt a) und b) und/oder nach Schritt b) auf die Lignozellulose-haltigen Zerkleinerungsprodukte oder auf den verpressten Holzwerkstoff aufgebracht wird.In a preferred embodiment, the method according to the invention is one comprising the steps

1. a) contacting lignocellulose-containing comminution products with adhesives;
2. b) pressing the mixture from a) under heat treatment,

characterized in that the additives are present on a carrier material and this additive-containing carrier material between step a) and b) and / or after step b) is applied to the lignocellulose-containing crushed products or to the compressed wood material.

That is, it is preferred in the invention that the additives are applied to a support material. This applies in particular to the antioxidants as additives according to the invention. Such application may be by known means and methods. These methods include application by spraying, impregnation, dipping or brushing applied to the substrate.

In this case, the additive may be present on one side or both sides of the carrier material. The additive is preferably present on the side facing the wood-based material. The carrier material may e.g. a cellulose layer, paper or the like. According to the invention, the carrier material can be applied to the wood material prior to pressing the mixture or after pressing. For solid wood as a cervical spine, the carrier material containing the additive is applied to the solid wood accordingly.

In addition, by the carrier material, a covering of the wood material and thus the emission of VOC and VVOC be additionally prevented.

The carrier material may be transparent or formed with a decor. The support materials may be conventional, so-called overlay products or, for example, 100% cellulose paper, as used in the field of the production of wood-based materials, such as panels. Optionally, after application of the additive to the carrier material, a drying of the additive at room temperature, before the additive-containing carrier material with the wood materials or the lignocellulose-containing crushing products is associated with adhesives.

For example, the carrier material may be soaked, sprayed or otherwise impregnated with the additive. This carrier material is then applied before spreading on the conveyor belt and scrape after scattering but before pressing. In an alternative form, after pressing, the support material is applied to the wood material, e.g. rooted or otherwise connected to the wood material. It is preferred that in wood-based panels, such as OSB boards, fiberboard, plywood or chipboard but also solid wood, the support material is applied on both sides of the cervical spine. It is preferred that the additive is present at least on the HWS side facing.

In a further preferred embodiment, according to the invention, the additive is introduced onto the lignocellulose-containing comminuted product before the pressing and after the spreading or laying. In this case, the additive is preferably added before compression but after defibering or machining and in particular after drying.

The additive may be in the form of an aqueous solution or as a powder mixture directly after the pressing operation, e.g. be applied by spraying by means of nozzles on one or both sides of the produced wood material. Alternatively, an entry can be made by rolling.

In another embodiment, the additive can be dosed as a solution or as a powder to the lignocellulose-containing comminution products or the mixture of lignocellulose-containing comminution products and adhesive. In this case, a metered addition can also take place before the dryer but after defibering or cutting. The time of metering depends on the form of the additive, for example as an aqueous solution or as a powder.

For example, in the manufacture of OSB boards, the additive may be incorporated only in portions of the board. In this case, the additive is preferably introduced at least into the regions of the wood-based panel that form the covering layer, such as an OSB board. Furthermore, the additive may optionally be applied with a carrier material both before the pressing and after the pressing.

It is particularly preferred that the wood-based materials are those made of wood chips, wood strands or wood fibers as lignocellulose-containing crushed products.

In particular, it is preferred that the wood material is an OSB board. If appropriate, the wood-based materials may be further coated with known layers, such as a lacquer layer, decorative layer or wearing layer. The additives may also or only be present in these layers. That is, the carrier material may be formed as a decorative layer, lacquer layer, wear layer or according to sub-layers.

In an alternative embodiment, the cervical spine is solid wood and the additives are applied to the cervical spine by known methods.

On the one hand, the additives to be used according to the invention are alcohols, in particular polyhydric alcohols. It is particularly preferred that these alcohols be added together with a catalytically effective amount of acid to allow for acid-catalyzed reaction of the alcohols. The alcohols may then be e.g. react with resulting aldehydes to form acetals.

Fats and oils are esters of polyhydric alcohols, usually glycerol, with saturated and unsaturated fatty acids. Due to the oxidative degradation of these fats and fatty acids in the pressing process at high temperatures arise z. B. aldehydes. Upon addition of glycerine or other, especially polyhydric, alcohols with a small amount of acid for acid catalytic conversion, the aldehydes react to form acetals. In this case, for glycerol z. B. three hydroxy groups available. It is therefore preferred that polyhydric alcohols are added as additives.

Another reaction pathway in addition to the acetal formation is the esterification with fatty acids from the wood. This is also usually acid-catalyzed. The fatty acids are esterified, thus counteracting a degradation of the fatty acids to VOC and WOC.

It is therefore particularly preferred that, when alcohol is used as an additive, acid is added to the acid-catalytic conversion of the alcohols. In this case, small amounts of acid are sufficient, which catalyzes this.

Preferred alcohols are polyhydric alcohols, in particular glycerol or alkylene glycols, such as ethylene glycol, propanediol, butanediol, etc.

As another additive, an antioxidant can be used. Antioxidants allow trapping of radicals that z. B. at high temperatures or light. At high temperatures or light z. For example, hydroxyl radicals that have the ability to rapidly oxidize other substances. This easily forms VOCs and VVOCs from the natural components in the wood. The antioxidants, especially the antioxidants selected from ascorbic acid, vitamin E or butylhydroxytoluene (BHT), have the ability to trap such radicals and thus prevent the formation of VOCs or VVOCs from the constituents of the wood. According to the invention, these antioxidants are incorporated or applied in or on the carrier material.

It is preferable that the additives are added in an amount of 0.5 to 5% by weight of solid solid in terms of dry wood.

When using the additives according to the invention in the manufacture or processing of wood materials, such. As OSB boards or MDF boards but also plywood and solid wood, a significant reduction of VOC or VVOC including the aldehydes was surprisingly observed. In addition, a significantly lower emission of other volatile organic compounds was observed. Emission reduction is achieved both during manufacture and during later use. This is all the more surprising, since it could not be assumed that due to the large number of reactive compounds that are present in the wood, this additive VOC or VVOC and in particular the aldehydes can effectively reduce their emission.

The lignocelluloses, such as the wood-based materials or the comminuted products thereof, may be both conifers and hardwoods. Even mixtures of these two types of wood are possible. Preferably, the wood chips, strands or wood fibers come from conifers. The wood materials which can be produced by the production process according to the invention can be prepared according to known processes. In addition, the method can also be supplemented by other methods known to those skilled in the art for reducing the emission of volatile organic compounds or very volatile organic compounds, such as aldehydes.

The wood-based materials (HWS) may preferably be chipboard wood made of wood chips, OSB strands of wood strands, plywood boards of wood veneer and wood fiber boards, in particular MDF boards, of wood fibers. However, the term "wood-based materials" also includes plywood and, in particular, solid wood. Preferably, the wood materials OSB boards and lightweight and super light MDF boards.

Lignocelluloses are understood to mean lignocellulose-containing materials, such as wood. The resulting comminution products of lignocellulose include, in particular, wood strands, wood chips, wood fibers as well as wood veneers.

The adhesives used in the process according to the invention comprise, as adhesives, phenol-formaldehyde adhesive, isocyanate-based adhesive, urea-formaldehyde adhesive, melamine-urea-formaldehyde adhesive, melamine-urea-phenol-formaldehyde adhesive, tannin-formaldehyde adhesive or a mixture thereof.

In a further aspect, the present application is directed to the use of a composition containing an alcohol as defined herein optionally in combination with catalytically effective amounts of an acid and / or an antioxidant as defined herein for reducing the emission of VOC and VVOC, respectively , in particular saturated and unsaturated aldehydes, in the production and use of wood materials of lignocellulose. This use is characterized in that the additive during the manufacturing process of the wood material is registered or applied. The additive is preferably applied or applied in this case, as stated above, as is preferred with the aid of a carrier material.

The use is particularly advantageous for adhesives selected from phenol-formaldehyde adhesive, isocyanate-based adhesive, urea-formaldehyde adhesive, melamine-urea-formaldehyde adhesive, melamine-urea-phenol-formaldehyde adhesive, tannin-formaldehyde adhesive or a mixture thereof is used.

The additives are particularly suitable for use at least in the top layer of OSB boards or wood fiber boards.

The use of the additives preferably takes place in an amount of from 0.5% by weight to 5% by weight of solids, based on atro-wood.

Finally, in a further aspect, the present application is directed to wood materials obtainable by the process according to the invention. These wood-based materials are, in particular, fibreboards, in particular lightweight and superlight MDF boards or OSB boards, but also solid wood.

With the aid of the method according to the invention, it is possible with low dosage of the additives to reduce an emission of VOC or VVOC from wood-based materials during production but also during use. When using carrier materials, it is additionally possible to suppress the emission of VOC or VVOC by covering.

In addition, the additives used according to the invention are particularly advantageous in terms of a longer-term effect for suppressing the emissions of VOC or VVOC, since the additives present in the carrier material or in the outer layer also avoid the formation and emission of VOC or VVOC in the longer term.

In the following, the invention will be explained in more detail by means of examples, without being limited to these.

Example 1: Production of low emission OSB

A reference plate and two plates were made using glued strands from current production (12% MUPF as adhesive) using the additive glycerin and ascorbic acid. These plates were then pressed into a format of 10mm x 300mm x 300mm and a bulk density of 530kg / m ³ . Parameters for pressing are shown below Table to find. Before pressing, the glued strands were mixed with the respective additive. Furthermore, a part of the additive was sprayed on the surface of the plate after pressing. Sample A contains the additive glycerol in a dosage of 5 wt .-%. Addition of Additive A further added a few drops of hydrochloric acid for catalysis. Sample B contains the additive ascorbic acid in an amount of 1% by weight on atro wood. Table 1 Press diagram pressing stage Pressure [N / mm ² ] Time T [° C] 1 2 60 200 2 1 60 200 3 0.2 10 200

After cooling the plate, it was sealed airtight and stored for analysis.

Example 2: Determination of the emission of VOC from OSB material and methods material

Samples were prepared from the above-obtained OSB plates measuring 210 × 210 × thickness mm ³ . From the edge of these samples a 7mm wide strip was taken. This was then separated into two samples with a length of 95mm. One sample each was placed with the top side and the other with bottom side oriented towards the air flow in the topo-extractor. The results are expressed as the mean of these two measurements.

Method: Thermo-extraction

For a qualitative and comparative study of the emission potential of structurally similar materials, the thermo-extraction method is suitable.

The different samples were characterized with a so-called thermo-extractor (TE1, Gerstel, Mülheim ad Ruhr, Germany). It is a glass tube with a relatively small volume of about 25.9 cm ³ , which is located in the thermo-extractor. Throughout the system, a continuous nitrogen flow (100ml / min-1) is passed, which - as in the conventional test chamber tests - is passed over an adsorbent at regular times. According to DIN ISO 16000-6: 2004, these were analyzed in a GC-MS with thermosorption and cold trap. The whole system was operated at room temperature (23 ° C). Described was the method of Scherer et al. (Dangerous substances - clean air, 2006, 66 (3), 87-93 ). In order to achieve always the same and thus reproducible conditions, a steel sample holder was used which leaves a potentially emitting sample surface of about 7.1 cm ² . In illustration 1 Thermo-extractor, sample holder and the sample dimensions are shown. The conditions for the thermo-extraction are summarized in Table 2. 11 air volumes were sampled 10 minutes after the samples were placed in the thermo-extractor. The results are expressed as the substance quantity in relation to the air sampling volume (μg m ^-3 ). Table 2: Conditions for thermo-extraction parameter property Temperature in ° C RT Mass flow in ml min ^-1 100 Room volume in m ³ 0.00002586 Air change rate in h ^-1 232.0 Sample surface in m ² 0.00075 Room load in m ² m ^-3 29.1 Area-specific ventilation rate in m ³ - ² h ^-1 8.0 carrier gas nitrogen

The results of the study are shown in Table 3. Table 3: Results μg / m ³ Sample 0 Sample A Sample B aldehydes 681 153 42 Saturated aldehydes 651 140 31 Unsaturated aldehydes 18 3 1 hexanal 577 124 26 2-heptenal 12 3 1 2-octenal 6 0 0

As can be clearly seen, a clear avoidance of aldehydes is observed in samples A and B with the respective additive. In particular, the saturated but also the unsaturated aldehydes are significantly reduced.

The results are again graphically in the FIG. 1 shown.

Claims (15)

Process for the production of optionally coated wood materials of lignocellulose, in particular chipboard, fiberboard or OSB boards, comprising the steps: a) contacting lignocellulose-containing comminution products with adhesives; b) pressing the mixture from a) under heat treatment, characterized in that in the contacting according to step a) and / or between the contacting according to step a) and the compression according to step b) and / or after the compression according to step b) to avoid the emission of volatile organic compounds (VOC) or very volatile organic compounds (VVOC), in particular unsaturated or saturated aldehydes, further at least one additive selected from alcohols, optionally in combination with a catalytically effective amount of acid, and / or an antioxidant is added as an additive. Process for the preparation of optionally coated wood-based panels according to claim 1 comprising the steps a) contacting lignocellulose-containing comminution products with adhesives; b) pressing the mixture from a) under heat treatment, characterized in that the additives are present on a carrier material and this additive-containing carrier material between step a) and b) and / or after step b) is applied to the lignocellulose-containing crushed products or to the compressed wood material. Method according to one of claims 1 or 2, characterized in that the additive is a polyhydric alcohol, in particular glycerol, ethylene glycol or propanediol. Method according to one of claims 1 to 3, wherein further acid for the acid-catalytic reaction of the alcohols with aldehydes or fatty acids is introduced. Method according to one of claims 1 or 2, characterized in that the antioxidant is ascorbic acid, vitamin E or butylated hydroxytoluene. Method according to one of claims 2 to 5, characterized in that the carrier is a cellulosic material, such as paper, which is coated on one or both sides with the additive or impregnated. A method according to claim 6, characterized in that the carrier material is applied to the lignocellulosic crushing product before pressing and after spreading or laying and / or after pressing on the pressed wood material. Method according to one of claims 1 to 5, characterized in that the additive is applied after step b) on one or both sides of the pressed wood material and / or introduced into at least the outer layer forming, lignocellulosic crushing products. Method according to one of the preceding claims, characterized in that the crushed products before the pressing but after defibering or cutting the additive is added. Method according to one of the preceding claims, characterized in that the wood-based materials are those made of wood chips, wood strands or wood fibers as lignocellulose-containing comminution products. Method according to one of the preceding claims, characterized in that the amount of additive added is between 0.5 to 5 wt .-% solids based on atro wood. Use of a composition containing an alcohol, optionally in combination with catalytically effective amounts of acid and / or an antioxidant for reducing the emission of VOC or VVOC, in particular saturated and unsaturated aldehydes, in the production and use of wood materials of lignocellulose, characterized in that the additive can be introduced or applied during the production process of the wood-based material, preferably with the aid of an additive-containing carrier material. Use according to claim 12, characterized in that the additive is used at least in the top layer of OSB boards or wood fiber boards. Use according to one of Claims 12 or 13, characterized in that the additive is metered in an amount of from 0.5% by weight to 5% by weight of solid, based on dry wood. Wood material obtainable by a process according to one of claims 1 to 11, preferably fiber boards, in particular light and superlight MDF boards or OSB boards.

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