EP1801290B1 - Method and system for applying particulate solids to a substrate - Google Patents

Description

The invention relates to a method and a system for introducing particulate solids into a substrate.

As a substrate mainly papers, especially carrier papers or decor papers, but especially plates and panels made of plastic, wood or wood material are referred to below, which are used on ceiling, wall or floor.

The application of particulate solids is particularly interesting when thin layers of particulate solids are to be applied to a substrate. The particulate solids are relatively heavy and hard. They have a specific gravity of more than 2 g / cm ³ , usually more than 3 g / cm ³ . The Mohs hardness is 8-10. The typical application for the present invention is the application of corundum, silicates or other particulate solids to a substrate to improve its surface properties. For example, the application of corundum improves the abrasion resistance of resin layers and surface coatings built therefrom. The essential requirement here is that the particulate solids do not form the surface of the substrate. They must be embedded in a near-surface layer to B. to achieve improved abrasion resistance. In synthetic resin layers interspersed silicates improve z. B. the scratch resistance of surface coatings.

For the application of such particulate solids, various technical solutions are known. One set of proposals is to incorporate the particulate solids into liquids from the start and to roll, lift or spread them. For example, this describes WO 00/44984 , the WO 93/17182 , the DE 196 04 907 or the DE 195 08 797 a dispersion containing particulate Solids. This dispersion is applied through a rinsing nozzle from below onto the respective substrate to be coated. It is also proposed to add additives to such dispersions which make the particulate solids easier to handle. As additives, fibers and / or spherical bodies (glass beads) are proposed. The disadvantage here is that the preparation and processing of the dispersion is very complex, because settling of the particulate solids must be avoided. Even in the case of brief interruptions of production, the application device must be completely cleaned, as otherwise the dispersion will add lines and nozzles. The order volume also fluctuates to a relatively high degree.

Alternatively, the beats WO 2005/042644 to scatter such particulate solids onto the substrate. Via a roller arrangement, under which the substrate is passed, particulate solids are scattered onto the substrate. This arrangement is mechanically easy to manufacture and operate, but the uniformity and accuracy of the job is not satisfactory and the mechanical wear is very high. In addition, in a second step, very expensive fibers have to be applied to the surface of the substrate and aligned in a targeted manner in order to ensure the embedding of the particulate solids.

DE 40 37 650 shows an apparatus in which a ceramic article is coated with synthetic resin.

All solutions must deal with the fact that the particulate solids such as corundum, silicates or other particles are usually very abrasive. The methods known in the art therefore attempt to minimize the contact between the particulate solids and the respective conveyors so as to minimize wear on the conveyors. The extremely complex embedding of the particulate solids in synthetic resin effectively veils the particles. Scattering via a roller arrangement avoids interfering friction wherever possible.

It is therefore an object of the invention to provide an apparatus, a method and a wood-based panel in which particulate solids can be economically embedded in a substrate and in a surface coating. This object is achieved by a device according to claim 1, a method according to claim 13 and a wood-based panel according to claim 18.

The solution according to the invention provides a device which is designed for spraying particulate solids on a substrate which is coated with a moist and / or tacky synthetic resin layer, with a conduit at the first end of which means for generating gas pressure are arranged and their second end having a free orifice further comprising a particulate matter reservoir and provided with a nozzle for generating a pressure differential, the reservoir and the nozzle being inserted into the conduit such that, in the operating condition, the pressure differential created by the nozzle particulate solids are transferred from the reservoir into the conduit and fluidized, which are then transported to the free mouth of the conduit from which the particulate solids then exit and are sprayed into the moist and / or tacky synthetic resin layer.

Experiments have shown that - contrary to the previous opinion of the experts - a spraying of particulate solids on a substrate - and thus a spraying of the particles in the moist and / or sticky synthetic resin layer - is readily possible. The wear on the device is surprisingly low, especially if the solid particles are sufficiently fluidized. The device of the invention requires for spraying the particulate solids hardly moving components, which is very advantageous for industrial application. The fact that only the solid particles are sprayed, a particularly accurate distribution of the particulate solids is achieved.

The turbulence generated by the pressure difference among the solid particles is essential for uniformly spraying the particulate solid. A preferred embodiment of the device according to the invention provides that a Venturi nozzle is inserted into the conduit. It creates a negative pressure in the pipe. The Venturi nozzle is inserted into the line of the device according to the invention in that it draws the particulate matter from the reservoir into the line by the negative pressure it generates, where the particles are swirled and entrained in the gas stream until they are always still homogeneous gas-solid mixture impinge on the moist and / or sticky synthetic resin layer of the substrate, where the solid particles are deposited as a very uniform layer and sink into the wet resin layer. According to a further preferred embodiment of the device according to the invention, the particulate solids are fluidized in the operating state in the reservoir. They are preferably traversed by air or other inert gas and are kept in this way in the reservoir in motion.

According to the invention, the device according to claim 1 is provided with at least one spray nozzle on the mouth. The spray nozzle makes it possible to control the coating of the substrate very precisely. Depending on the choice of nozzle, the shape of the spray cone can be adjusted as desired in order to achieve a predetermined spray result on the substrate. The shape of the spray nozzle, for example, also depends on whether the mouth of the line is stationary or movable (we will discuss this below). A wide range of nozzles or nozzle openings can be used for the device according to the invention, for example nozzles with an annular opening or nozzles with a slot-shaped opening. To broader substrates z. B. wood-based panels to coat, it is also possible to arrange several spray nozzles side by side. Several spray nozzles can communicate with the mouth of the pipe via a manifold, without affecting the uniformity of the spraying process. In this case, a plurality of devices according to the invention can be arranged in parallel, which are each equipped with one or more nozzles. The nozzles are adjustable according to a further advantageous embodiment about their longitudinal and or transverse axes.

The lines of the device according to the invention can be selected depending on the application. They can be fixed pipes (pipes) or flexible pipes (hoses). Hoses are particularly advantageous when the mouth of the second end or possibly arranged thereon spray nozzle are designed to be movable. Lines and spray nozzles, but also the distributor can be made according to a preferred embodiment of the invention made of plastic. The device is thus assembled in a cost effective manner from lightweight components. It is also possible to combine components made of different materials. So z. B. the lines are each made in sections of metal and plastic. Also ceramic components can be used for the preparation of the aforementioned lines, spray nozzles or manifolds.

It is preferred if the device according to the invention also has means for conveying the substrate. Depending on whether it is a decorative paper, veneer or a wood-based material surface, the substrate can simply be placed on the conveyor or fixed there. It is then passed under the stationary or movable mouth or spray nozzle of the device and coated with the particulate solid. If necessary, the substrate can be fixed on the means for conveying, be it by negative pressure, be it z. B. by oppositely arranged rollers or conveyor belts. The provision of such conveying means enables the industrial-economical coating of the solid solid particle substrate.

It is regarded as a particular advantage of the invention that the device according to the invention can indeed certainly be used for itself. However, the device is preferably integrated in a system for surface coating. The application of synthetic resin or the painting of wood-based surfaces is usually carried out in impregnation or painting at working speeds of about 30 m / min to about 100 m / min, often between 40 m / min and 60 m / min. At these operating speeds, the spray device according to the invention can be readily integrated into these systems. Here, the compact design of the device proves to be very beneficial. In integrated devices conveying means are frequently provided which transport the substrates to be processed or coated through all stations of the complex coating installations.

It can be processed according to the invention, a wide range of particulate solids in the apparatus according to claim 1. Often corundum is used, but it is also conceivable the use of silicates, carbides or diamond dust. The particulate solids having a specific gravity of more than 2 g / cm ³ , often more than 3 g / cm ³ , are usually used in diameters of 30 to 100 .mu.m, preferably in diameters of 40 .mu.m to 60 .mu.m. They are made by spraying or in the resin layers on the surface of carrier or decor papers but also embedded in resin layers directly on the surface of wood-based materials to improve the surface coating properties, typically to increase abrasion resistance or scratch resistance. It is preferred that the moist and / or tacky synthetic resin layer when spraying or spraying the particulate solids has a layer thickness which has at least half the average diameter of the particulate solids, ie, layer thicknesses of 15 .mu.m to 50 .mu.m. When the particles are sprayed in, they are then largely surrounded by the synthetic resin by displacement of the synthetic resin. According to the invention, a further synthetic resin layer is also applied after the spraying process in order to complete the embedding of the particulate solids.

With the device according to the invention almost any amounts of solid particles can be applied to the substrate. It is amazing that tests have shown that even small amounts of particulate solids can be applied reliably and evenly. Quantities of up to 100 g / m ² , preferably of up to 80 g / m ² , more preferably of up to 50 g / m ² , advantageously of up to 30 g / m ² can by means of the device according to the invention with high uniformity on the Substrate are applied, and - as mentioned above - at high operating speed.

It is considered to be particularly advantageous that with the device according to the invention a high uniformity of the application of solid particles is achieved, which is clearly superior to the previously known methods. The uniformity of the particle application is important in several respects: on the one hand, an increasing application of solids adversely affects the transparency of the substrate surface. On the other hand, if there are high fluctuations in the uniformity of the order, significant safety measures must be taken when applying solid particles, if specified quantities are to be observed. This adversely affects the cost and leads to increased wear on application devices.

According to the invention, the solid particles can with an accuracy of up to ± 0.8 g / m ^2, preferably to be scattered to ± 0.5 g / m ² onto the substrate. Especially preferred the order accuracy is even more narrow and according to the invention is up to ± 0.3 g / m ² . Advantageously, a job accuracy of up to ± 0.1 g / m ^{2 is} achieved. In known methods, the achievable distribution accuracy is greater than ± 2 g / m ² . The solution according to the invention therefore offers considerable economic and technical advantages.

The device according to the invention offers, according to an advantageous embodiment, various possibilities for individually setting the order of the particulate solids. Thus, the free mouth of the line, possibly with the attached spray nozzle, both parallel to the plane of the substrate to be coated to be arranged movable, for example, be moved on a rail over the substrate to be coated. Alternatively or additionally, the distance to the surface can also be changed. The movement of the free orifice relative to the substrate is matched to the feed rate of the conveying means, which transport the substrate through the device according to the invention. Alternatively, the device according to the invention can also be adapted to the respective substrate by the number of the spray nozzle. For example, groups of nozzles may be connected via manifolds to the mouth of the conduit to achieve a predetermined spread pattern. Due to these diverse adjustment possibilities, the application of the particulate solids can be adapted to a large extent to the substrate to be sprayed in a wide range. Application methods known from the prior art do not allow such an individual adjustment of application quantity and distribution of the particulate solids.

The device according to the invention is designed according to a preferred embodiment so that further means for modifying, in particular for coating the particulate solids in the line are provided. The modifying may be a coating, for example to impart better binding to the particulate solids on the substrate or to impart improved optical properties to the particulate solids. Often, the solid particles z. B. silanized to achieve better adhesion to the substrate. The means for modifying are inserted into the conduit between the reservoir and the mouth, the modifying agent is sprayed into the conduit or, preferably, in the same manner as the particulate solids by a pressure change in the conduit entrained and then clad the particulate solids.

The inventive device further allows due to the high accuracy in applying the particulate solids and applying varying amounts, ie a precise differentiation between areas where solid is applied to the substrate and areas where less, more or no solid on the substrate is applied. Substrates with discrete sections of varying amounts of particulate solids can be produced.

• Beschichten des Substrats mit einer feuchten und/oder klebrigen Kunstharzschicht
• Aufbauen von Gasdruck in einer Leitung
• Erzeugen eines Druckwechsels in der Leitung
• Verwirbeln und Mitreißen von partikelförmigen Feststoffen mit einem spezifischen Gewicht von mehr als 2 g/cm³ in die Leitung
• Einsprühen von verwirbelten, partikelförmigen Feststoffen aus der Leitung in die feuchte und/oder klebrige Kunstharzschicht des Substrats.

The inventive method provides that particulate solids are sprayed into a moist and / or tacky synthetic resin layer of a substrate with the steps:

• Coating the substrate with a moist and / or tacky synthetic resin layer
• Building gas pressure in a pipe
• Generating a pressure change in the line
• Swirling and entrainment of particulate solids having a specific gravity greater than 2 g / cm ³ into the conduit
• Spraying fluidized, particulate solids from the conduit into the moist and / or tacky resin layer of the substrate.

According to the invention, it is provided that particulate solids are sprayed into a synthetic resin layer with a moist and / or tacky surface of a substrate. The spraying of such a moist and / or tacky resin-coated substrate with particulate solids allows for very uniform coating of the substrate. Typically, it can be a substrate that has not yet reacted, or a substrate coated with paint or varnish. But it can also be a decorative paper soaked with not yet dried melamine resin. Embedding the sprayed particulate solids in the moist and / or tacky surface of the substrate requires much less use of such wet and / or tacky coating agents than conventional processes, eg, those which apply the solid particles in the form of dispersions. The subsequent drying or curing of the moist and / or sticky coating additionally contributes to the fixation of the particulate solids. It is essential that the particulate solids penetrate as deeply as possible into the synthetic resin layer. They should not rest on the synthetic resin layer but be embedded in this layer.

It has proven to be advantageous to dry or cure the moist and / or tacky synthetic resin layer after introduction of the particulate solids. Usually, this is done in a dryer or oven, which passes through the coated substrate.

It is the object of the invention to introduce the sprayed-on particulate solid as completely as possible into the synthetic resin layer. Solid particles which do not penetrate into the synthetic resin layer or which do not adhere to the surface of the substrate can be returned to the reservoir via a suction system and subsequent sighting. If the process according to the invention is carried out in a manner in which the particulate solids do not penetrate deeply into the synthetic resin layer and are accordingly not completely enclosed by the synthetic resin, then it is advisable to subsequently apply at least one layer of synthetic resin containing the still exposed portions of the particulate Encloses solids.

The inventive method is implemented in the apparatus according to the invention described above. It is simple and straightforward in technical application, in particular it is insensitive to downtime. The special requirement of the deep penetration of the particulate solids in the resin layer is perfectly implemented. The relatively high specific gravity of the particulate solids in conjunction with the air flow causes a sufficiently deep penetration into the resin layer.

The gas pressure is built up by simple means, for example by a pump or by means of a connection to a centrally installed compressed air line. The change from the higher to the reduced pressure is expediently brought about by a nozzle, preferably by a Venturi nozzle. The particles are removed from the reservoir due to entrained by the nozzle pressure drop in the line, about the principle of operation of the water jet pump.

According to a further advantageous embodiment of the method according to the invention, the spray cone for the solid to be sprayed onto the substrate is predetermined by a spray nozzle placed on the mouth of the pipe. The spray cone can-as described above in the description of the device according to the invention-be adapted to the individual requirements of the respective substrate by optimizing the type and orientation of the spray nozzle. The optimization of the spray nozzle is carried out by practical experiments.

For example, the spray nozzle can be designed so that the substrate is sprayed intermittently. There are then sections of the substrate z. B. web-shaped or in transverse stripes sprinkled with solid solids. For example, portions of a wall, ceiling or floor panel are sprinkled only where a particulate surface is also desired. There, where z. B. pitch saws after the scattering of the solid particles to set to separate the panels, a disturbing, wear on the saw causing coating with particulate solids can be omitted or at least significantly reduced.

The aforementioned application rates of up to 100 g / m ² and in particular the accuracy of the coating with up to 0.8 g / m ² , preferably up to 0.1 g / m ² can by tuning between gas flow, nozzle geometry, in particular the scattering nozzle and speed of the substrate moved relative to the device, but also by increasing or decreasing the distance between the substrate and the spray nozzle. It is within the usual scope to optimize such devices to achieve the optimum setting of these parameters, tailored to the particular application.

Furthermore, the invention relates to a particularly uniformly coated with solid particles substrate, wherein the particulate solid is introduced into a synthetic resin layer. Unlike previously, substrates, particularly decorative papers and panels, can be provided that are within close tolerances with particulate solids are coated. The tolerance for the order quantity of the particulate solids amounts to a simple embodiment of the invention up to ± 0.8 g / m ² , according to a preferred embodiment, the tolerance is up to ± 0.5 g / m ² , more preferably up to ± 0.3 g / m ² , advantageously up to ± 0.1 g / m ² . The uniform layer distribution allows specified for the respective substrate abrasion, z. B. to achieve a certain abrasion resistance, with an overall lower use of solid particles to achieve than previously possible.

According to a preferred embodiment of the invention, the thus coated substrate is part of a multilayer surface coating. According to the invention, the synthetic resin layer according to the invention, which is coated particularly uniformly with corundum, is covered by a further synthetic resin layer.

Fig. 1

eine schematische Darstellung einer bevorzugten Ausführungsform der erfindungsgemäßen Vorrichtung;

Fig. 2

eine schematische Darstellung einer bevorzugten Ausführungsform der erfindungsgemäßen Vorrichtung mit mehreren Düsen;

Fig. 3

eine schematische Darstellung der Absaugung einer bevorzugten Ausführungsform der erfindungsgemäßen Vorrichtung.

Essential details of the invention are explained below using an exemplary embodiment. It shows:

Fig. 1

a schematic representation of a preferred embodiment of the device according to the invention;

Fig. 2

a schematic representation of a preferred embodiment of the device according to the invention with a plurality of nozzles;

Fig. 3

a schematic representation of the suction of a preferred embodiment of the device according to the invention.

Fig. 1 shows a device 2 for spraying particulate solids. The device 2 has a line 4, the first end 6 is connected to a here schematically indicated by "D" compressed air line. The line 4 (here with a line cross section of 6 mm) and thus also the Venturi nozzle is acted upon via the compressed air line D with an air flow volume of 1.5 m ³ / h. The second end, the free mouth 8 of the conduit 4 is provided with a spray nozzle 10. The line 4 passes through a reservoir 12 containing particulate corundum. The corundum has a specific gravity of 4 g / cm ³ . In the region of the reservoir 12 containing corundum, a Venturi nozzle 14 is inserted into the conduit 4. By the negative pressure generated in the venturi nozzle 14 in the operating state is via a suction line 16 corundum sucked from the reservoir 12 under swirling in the line. The delivery air flow is 6 bar.

The container 12 is open to the environment, it is refilled regularly in accordance with the consumption of corundum. The line 4 is mainly made of stainless steel. However, it has a section 4a, which is made of flexible plastic. At least in areas where plastic components are used, the system is earthed to avoid static electricity. Due to the flexible plastic conduit 4a, the free mouth 8 can be aligned with the nozzle 10 attached thereto at exactly the desired distance from the substrate to be coated.

From the reservoir 12 occurs at the pressure ratios given above, an amount of 50 g / m ² corundum -schematisch shown with "K" - in the gas stream and is sprayed from the spray nozzle 10. The corundum K has an average diameter of 60 microns. The corundum K is sprayed from the nozzle 10 onto the surface of the substrate 18. The substrate 18, here a high-density fiberboard (HDF board) is coated with a moist and sticky, not yet cured layer 20 of melamine resin (layer thickness 50 microns).

The spray cone 11 of the spray nozzle 10 is in Fig. 1 indicated; it extends over the entire width of the HDF plate 18. The substrate 18 is passed over conveying means, which are indicated as a roller 22, under the spray nozzle 10 at a speed of 60 m / min.

In the melamine resin layer 20 50 g / m ² corundum K is sprayed with a distribution accuracy of 0.5 g / m ² . The corundum particles sink almost completely into the melamine resin layer 20. Following the spraying of the corundum particles, the melamine resin layer is dried. Since the corundum particles and the melamine resin have approximately equal refractive indices, a transparent layer is produced.

Further exemplary embodiments explain advantages of the invention:

example 1

An overlay paper with a sheet weight of 30 g / m ² and a web width of 210 cm is filled with liquid melamine resin in a squeegee-type impregnation unit. The applied amount of melamine resin is about 120 g / m ² . The solids content of the melamine resin is 50%. The impregnated overlay paper is referred to below as impregnate. 20 g / m ^{2 of} corundum powder (particle size 40 μm) are sprayed onto the impregnate on the top side of the moist impregnate using a spray device which has twelve spray heads of a width of 210 cm. The spraying devices correspond to those in Fig. 1 illustrated device. The web speed of the impregnate under the twelve fixed spray heads is about 80 m / min.

The corundum powder is applied with a distribution accuracy of 0.5 g / m ² on the surface of the impregnate. The corundum powder applied to the impregnate sinks into the melamine resin layer. The corundum powder is completely enveloped by the melamine resin. The measured after drying thickness of the melamine resin corundum layer is about 100 microns. The extensive, if possible complete enveloping of the corundum powder by the melamine resin is a prerequisite for the desired here transparent coating.

The corundum-containing overlay paper is dried in a floating dryer to a residual moisture of 16 to 18% by weight, based on the dry content of the impregnate. Subsequently, an additional melamine layer of 30 g / m ² to 40 g / m ^{2 is} applied with a raster coater on the underside of the impregnate. When passing through further dryer zones of the suspended bed dryer, a residual moisture of from 6% by weight to 7% by weight of the impregnate is set.

The corundum-containing substrate is turned over and pressed onto a high-density fiberboard (HDF board) in combination with melamine resin-impregnated decor paper. The resulting panel can be used as a high-quality surface for laminate flooring in the abrasion class AC 4.

Example 2

An HDF plate is first decorated in direct printing in three-color printing on the top decorative. Subsequently, a melamine resin layer of 60 g / m ^{2 is} applied with a roller coater. In the still liquid melamine resin 15 g / m ^{2 of} corundum powder (particle size: 60 microns) with an in Fig. 1 sprayed schematically illustrated device.

The melamine coating with the corundum powder embedded therein is pre-dried in a hot-air dryer until the surface coating has a residual moisture content of about 15% by weight based on this. Subsequently, another protective layer of cellulose fibers and melamine resin is applied and this surface structure is precondensed with hot air so far that it is tack-free, but the melamine resin is not yet crosslinked.

The printed and coated with corundum plate is in a short-cycle press (16 sec. At 160 ° C at the plate surface, 3 N / mm ² ) pressed. In this case, a melamine film is placed on the underside of the HDF plate in return, which ensures that the underside of the plate is protected, and that the plate is flat. The finished panel is suitable as a panel for the decoration of walls, ceilings or floors.

Example 3

With reference to the Fig. 2 and 3 Below, a preferred embodiment of the device according to the invention will be explained. Like reference numerals refer to FIGS Fig. 2 . 3 the same components as in Fig. 1 ,

The container 12, which receives the corundum K, is provided with an air bottom 24. Through the air bottom 24, the container 12 is flowed through from its lower region by air, which fluidizes the corundum. In the Fig. 1 closer assembly of Venturi nozzle 14 and suction line 16 is shown here as an injector 26. The injector 26 supplies one or more lines 4, through which the fluidized corundum is conveyed to the spray nozzles 10. The pressure in the delivery lines is usually 0.2 to 4 bar, usually 1 to 3.5 bar.

The line or lines 4 open into a nozzle 28, the more nozzles 10, which are arranged distributed over the width of the substrate 18. The nozzle assembly 28 distributes the fluidized corundum K to the nozzles 10 via distributor lines 4b arranged in the nozzle assembly 28. The nozzle assembly 28 is freely adjustable in height above the substrate. Within the nozzle block 28, the nozzles 10 are freely adjustable about their axes.

The nozzle 28 is surrounded by a housing 30 which in Fig. 2 is indicated. To the housing 30, a suction 32 is connected. The suction unit 32 sucks the conveying air emerging from the nozzles 10 via the suction line 34. The air flow of the suction air is A in Fig. 2 indicated. This avoids unwanted turbulence over the substrate. In order to avoid the occurrence of a negative pressure, the housing 30 is open to the environment, preferably approximately at the level of the substrate 18. Thus, external air F can be sucked in to compensate for the pressure.

Fig. 3 shows a preferred embodiment of the spray and suction device. In order to avoid deposits on the top of the nozzle block 28, an inner hood 36 is inserted into the housing 30. In addition, a cover plate 38 closes off the side wall of the nozzle block 28 to the inner hood 36. In this way, a suction channel 40, which is flowed through by the suction air A and possibly sucked external air F. The fan 32 generates through the suction line 34 this air flow. The execution after Fig. 3 Effectively prevents deposits on the top of the nozzle block 28.

Claims (16)

1. A device for spraying particulate solids (K) onto a wood-based panel, a decorative paper or a veneer (18), having

   - a feed line (4) made of hoses (49) or tubes (4), at the first end (6) of which means (D) for generating a gas pressure are arranged and the second end of which has a free opening (8), having

   - a nozzle (14) which is inserted into the feed line (4), and which generates a vacuum in an intake line (16) in an operative state, having

   - at least one spraying nozzle (10) which is set onto the free opening (8) of the feed line (4), and having

   - a reservoir (12) for particulate solids (K), wherein

   - the reservoir (12) and the nozzle (14) are inserted into the feed line (4) such that in an operative state particulate solids (K) are transferred and swirled from the reservoir (12) through the intake line (16) into the feed line (4) by the vacuum generated by the nozzle (14), and are transported to the free opening (8) of the feed line (4), onto which the at least one spraying nozzle (10) is set, from which the particulate solids (K) then exit,
   characterized in that

   - a wet and/or adhesive synthetic resin layer (20) is applied to the wood-based panel, the decorative paper or the veneer (18), and

   - the nozzle (14) and the spraying nozzle (10) are designed to spray particulate solids (K) having a specific weight of more than 2 g/cm³ in such a way that the particulate solids (K) are extensively or completely covered with the wet and/or adhesive synthetic resin layer (20) following the spraying, and wherein

   - means for applying a further synthetic resin layer are provided.
2. The device according to claim 1, characterized in that the device (2) has feed lines (4) as well as at least one spraying nozzle (10) made of a synthetic material.
3. The device according to claim 1, characterized in that the second end (8) of the feed line is arranged in a stationary or movable manner with the installed spraying nozzle (10), in a plane parallel to the wood-based panel, the decorative paper or the veneer (18) and/or perpendicular to the wood-based panel, the decorative paper or the veneer (18).
4. The device according to claim 1, characterized in that means (22) for conveying the wood-based panel, the decorative paper or the veneer (18) are provided relative to the device (2).
5. The device according to claim 4, characterized in that the means (22) for conveying are designed for an operating speed of up to 30 m/min, preferably of up to 40 m/min, particularly preferably of up to 60 m/min, advantageously of up to 100 m/min.
6. The device according to claim 1, characterized in that it is designed for spraying particulate solids (K), in particular corundum, silicates, carbides, diamond powder or other metallic and/or ceramic hard material particles or mixtures of said solids.
7. The device according to claim 1, characterized in that it is designed for spraying particulate solids (K) having a diameter of 30 µm to 100 µm, preferably of 40 µm to 60 µm.
8. The device according to claim 2, characterized in that the feed line (4), reservoir (12), nozzle (14) and spraying nozzle (10) are designed such that in an operative state particulate solid (K) is sprayed in a quantity of up to 30 g/m², preferably of up to 50 g/m², particularly preferably of up to 80 g/m², advantageously of up to 100 g/m² into the synthetic resin layer (20) which is applied to the wood-based panel, the decorative paper or the veneer (18).
9. The device according to claim 1, characterized in that the feed line (4), reservoir (12), nozzle (14) and spraying nozzle (10) are designed such that in an operative state particulate solid (K) is sprayed with an accuracy of up to ± 0.8 g/m², advantageously of up to ± 0.5 g/m², preferably of up to ± 0.3 g/m², particularly preferably of up to ± 0.1 g/m² into the synthetic resin layer (20) which is applied to the wood-based panel, the decorative paper or the veneer (18).
10. The device according to claim 1, characterized in that the particulate solids (K) have a specific weight of more than 3 g/cm³, preferably of more than 3.5 g/cm³.
11. The device according to claim 1, characterized in that further means for modifying, in particular for coating the particulate solid, are arranged in the feed line (4), in particular means for silanizing.
12. The device according to claim 11, characterized in that the means for modifying are arranged in the portion of the feed line between the reservoir (12) and the free opening (8) of the feed line (4).
13. A method for spraying particulate solids into a wet and/or adhesive synthetic resin layer of a wood-based panel, decorative paper or a veneer, having the steps of

    - coating the wood-based panel, the decorative paper or the veneer (18) with a wet and/or adhesive synthetic resin layer,

    - building up a gas pressure in a feed line (4) which is provided with a nozzle (14),

    - generating a pressure change in the feed line (4) by generating a vacuum in an intake line (16) through the nozzle (14),

    - swirling and carrying along particulate solids (K) having a specific weight of more than 2 g/cm³ from a reservoir (12) through the intake line (16) into the feed line (4),

    - spraying swirled, particulate solids (K) from the feed line (4) into the not cured, wet and/or adhesive synthetic resin layer (20) of the wood-based panel, the decorative paper or the veneer (18), wherein the particulate solids (K) are extensively or completely covered with the wet and/or adhesive synthetic resin layer (20) following the spraying, as well as

    - applying a further synthetic resin layer

    - drying or curing the wet and/or adhesive synthetic resin layers following the introduction of the particulate solids.
14. The method according to claim 13, characterized in that the swirled, particulate solids (K) are sprayed by means of a spraying nozzle (10) into the synthetic resin layer (20) which is applied to the wood-based panel, the decorative paper or the veneer (18), wherein the spraying nozzle (10) is moved parallel and/or perpendicular to the surface of the wood-based panel, the decorative paper or the veneer (18) during spraying.
15. The method according to claim 13, characterized in that the particulate solid (K) is sprayed in a quantity of up to 100 g/m² into the synthetic resin layer (20) which is applied to the wood-based panel, the decorative paper or the veneer (18).
16. The method according to claim 13, characterized in that the particulate solid (K) is sprayed with an accuracy of up to ± 0.5 g/m², preferably of up to 0.1 g/m², into the synthetic resin layer (20) which is applied to the wood-based panel, the decorative paper or the veneer (18).

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