BE1026771B1 - Coated panel and method of manufacturing coated panels. - Google Patents

Abstract

Clad panel with at least one substrate (2) and a top layer (3) applied thereto, said top layer (3) comprising at least a decor (4) and a transparent or translucent wear layer (5), characterized in that the aforementioned wear layer (5 ) comprises a thermally cured acrylic resin, in particular wherein said acrylic resin has been cured by a thermally initiated radical cross-link reaction. The invention further relates to a method for manufacturing such coated panels (1), in particular floor panels.

Description

Coated panel and method of manufacturing coated panels.

This invention relates to coated panels, in particular to floor panels, as well as to a method of manufacturing floor panels.

More specifically, the invention relates to panels with a substrate and a top layer applied to it with a decor, for example a decor comprising printing. Such floor panels are well known per se, for example from WO 97/47834. The floor panels disclosed there concern, inter alia, floor panels with a substrate which mainly consists of an HDF plate with a laminate layer directly pressed thereon, which comprises one or more paper sheets soaked in melamine resin, including preferably also a paper sheet with a printing in, for example, a wood or stone motif. , namely a so-called decor paper. The aforementioned melamine resin forms, among other things, a transparent wear layer above the decor paper, but the transparency or transparency leaves much to be desired. At the bottom of the substrate there is a counter layer or balancing layer, also based on a paper sheet soaked in melamine resin. This counter layer compensates for residual tensile stresses present in the cured melamine resin of the top layer. It remains difficult to form very deep structures in the curing melamine surface. So-called white mountains often occur. These are zones where inclusions concentrate in the melamine surface. These mainly occur where deep indentations or structures are realized.

It is known that the melamine surface of such a laminate panel gives rise to ticking noises when using it. A variety of solutions to this problem are known from the prior art. It is known from WO 03/016655 to provide a sound-absorbing layer such as a cork layer under the melamine layer. It is known from WO 2010/088769, among others, to provide the melamine layers with a coating of a flexible monomer. WO 2009/101217 and WO 2010/070474 give examples of laminate panels in which the top layer, instead of melamine resin, consists mainly of

BE2018 / 5787 polyvinyl chloride (PVC) is built up. In the case of WO 2010/070474, these are panels with a printed decor that can be formed on the substrate and are finished with a transparent PVC layer.

Furthermore, it is known from WO 01/47726 that panels with a printed decor can be finished with a UV-curing or electron beam-curing acrylic resin. This process is difficult to integrate into existing laminate panel manufacturing processes and requires complex logistics of materials, complex machines, and results in high costs. For example, electron beam curing requires an inert atmosphere, making treatment at the plate level difficult and this technique mainly applies to smaller panels or sheets in a physically sealed lead space, with the aim of neutralizing the generation of unhealthy gamma radiation. These lead enclosures are thicker than 2.5 mm and can take on enormous weights. The photoinitiators required for UV curing have a detrimental effect on the quality of the surface obtained. The molecules used as photoinitiators are coming under increasing pressure due to the health risks they pose to humans.

The panels whose top layer is made entirely of PVC have a loss of scratch resistance compared to the traditional melamine surface. In addition, the PVC layer must be made considerably thicker than a melamine layer in order to obtain a comparable wear resistance. The nature and thickness of the PVC layer gives rise to a plastic-like appearance of the floor panel, especially in those cases where an imitation of a product such as wood, stone or ceramic is sought. The relief that can be obtained in a PVC layer is blurry, which diminishes the veracity of the imitation obtained.

In the panels whose top layer is obtained from UV-cured or electron beam-cured acrylic, such as in WO 01/47726, good surface properties are obtained. The relief that can be obtained in such a top layer is limited because structure foils have to be used, for instance as in EP 2 019 735.

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The present invention aims primarily to provide an alternative coated panel which solves one or more of the problems with the prior art panels.

To this end, the invention relates to a coated panel, preferably a floor panel, a wall panel or a furniture panel, with at least one substrate and a top layer applied thereon, the aforementioned top layer comprising at least a decor and a transparent or translucent wear layer, characterized in that the above wear layer includes a thermally cured acrylic resin.

The use of a thermally cured acrylic resin opens up new possibilities for the design of the wear layer, while retaining the excellent qualities of a wear layer made of acrylic resin. For example, the wear layer can be cured by means of a heated pressing operation with a structured pressing element. The inventors have determined that the structure of the pressing element is surprisingly very well copied in the curing acrylic resin. Unlike the curing melamine resin, the curing reaction of the acrylate resin is free of so-called chemical moisture or moisture produced as a by-product of the reaction, so that the risk of inclusions being formed in the transparent layer is limited, even when working with deep structures, for example, with a local depth of more than 400pm, or even 1 millimeter or more from the global surface.

In addition, the inventors have determined that a thermally cured acrylic resin can have better transparency than a thermally cured melamine resin as available from the prior art laminate panels. The inventors blame this on the strong shrinkage of a polycondensing melamine resin. Because of this, as well as due to the brittleness of the melamine resin, the melamine resin in the cured state exhibits a significant number of microcracks, unlike is the case with the thermally cured acrylic resin wear layer of the invention.

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Furthermore, the inventors have been able to determine that residual tensile stresses that may be present in the wear layer after curing are much smaller in the case of the invention than with prior art laminate panels, such that the risk that the panels or parts thereof obtained will have a curvature. display is severely limited, even when working without a backsheet.

The wear layer formed is further softer than a melamine surface and, together with the smaller residual tensile stresses in the surface, this property makes for more acceptable scratching sounds, namely a sound similar to that of real wood.

The thermal curing also makes it possible to obtain a more uniform curing than is the case with UV-cured acrylic resins. When UV radiation is used for curing, the penetration of the light is limited in depth. However, the thermal curing of the invention can be initiated by means of one or more thermo-initiators that are homogeneously, or substantially homogeneously, mixed with the acrylate resin. In this way, the curing reaction can occur substantially simultaneously and / or to the same degree throughout the thickness of a layer formed by acrylic resin. In addition, thicker cured layers can be formed, for example layers with a thickness between 50 and 1000 micrometers, more particularly between 100 and 300 micrometers.

The qualities of the acrylic resin are mainly manifested in the case that the aforementioned acrylic resin is cured at least by means of a thermally initiated radical cross-link reaction. The aforesaid curing preferably comprises at least a cross linking of double carbon bonds present in the acrylic resin, as may be the case with UV or electron beam cured acrylic resins.

According to a special possibility, the aforementioned acrylic resin has been cured, both by means of a thermally initiated radical cross-link reaction in which the double carbon bonds present in the acrylic resin cross-link, and by means of a

BE2018 / 5787 cross-link reaction of the urethane, epoxy or amine functions. The latter crosslink reaction is preferably initiated by an OH and / or an NH2 functionality and is promoted by the temperature used for the first crosslink reaction. For the purpose of the second crosslinking reaction, cross-linking agents are preferably added to the acrylate resin, such as isocyanate, aziridine, carbodiimide or the like. In a particular example, the acrylic resin comprises or consists of a polyurethane acrylate resin.

It is noted that the use of hardeners, such as isocyanate or aziridine, in a UV curable coating is known per se to the inventors as "dual cure". Such hardeners ensure that a second internal cross-linking, namely of the urethane, epoxy or amine functions, takes place only in an uncontrolled manner and possibly with a long delay after the previous UV curing. The above special possibility offers the possibility of providing coated panels with a wear layer obtained by applying a dual cure system, in which the first crosslinking concerns a thermal curing. Due to the thermal energy of the first cross-linking, the second cross-linking starts in a controlled manner and can take place in a short time. In other words, an “instant dual cure system” is created.

It is clear that the presence of a thermo-initiator in the acrylic resin used can make an important contribution to the quality and relief aspects of the obtained wear layer.

A thermo-initiator can be more broadly defined as a thermally unstable molecule that decays or decomposes on exposure to heat, at least in one or more radicals. The radicals formed then play the same role as the radicals generated by known photoinitiators in the UV curing of acrylate resins. The thermally obtained radicals initiate the polymerization reaction of the double carbon bonds of the acrylate differentials present in the acrylate resin.

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For the same purpose as in the first aspect, the present invention, according to an independent second aspect, relates to a coated panel having at least one substrate and a top layer applied thereto, said top layer comprising at least a decor and a transparent or translucent wear layer, characterized that the aforementioned wear layer has been obtained on the basis of a mixture of at least acrylic resin and a thermo-initiator. It is understood that the coated panels of the second aspect may exhibit the features of the first aspect or the preferred embodiments thereof. In particular, the mixture may further comprise cross-linking agents, such as isocyanate, aziridine, carbodiimide or the like, such that the aforementioned wear layer is obtained by means of the instant dual cure mentioned in the context of the first aspect. system.

Preferably, the aforementioned thermo-initiator is an organic peroxide, preferably benzoyl peroxide or lauryl peroxide. The inventors have determined that these thermointiators have a suitable minimum activation temperature necessary to obtain the decay in at least one or more radicals, such that a sufficiently hardened wear layer can be obtained with an acceptable energy consumption, namely at a modest curing temperature.

Other examples of organic and inorganic peroxides which can be used as thermo-initiators are 2-butanone peroxide, persulfate, peroxy diphosphate and persulfate.

In addition to peroxides, alternatively azo polymerization Initiators can also be used, such as azo nitrile, azo ester, hyponitrites and / or azo amide. Another alternative is to use cesium ions.

Preferably, the aforementioned mixture comprises 0.1-5 parts of thermo-initiator per 100 parts of acrylic resin, and more preferably 0.5-2 parts of thermo-initiator per 100 parts of acrylic resin. By changing the concentration of the thermo-initiator, the obtained chain length of the polymerized acrylate resin can be adjusted. With larger amounts of thermoinitiator, the reaction comes to an end earlier and shorter chain lengths are obtained, with smaller quantities longer chain lengths are obtained. With 0.5-2

BE2018 / 5787 parts thermo-initiator per 100 parts acrylate resin, a balance is reached between the speed of the reaction and the degree of cross-linking or the chain length. Preferably, the time frame to half or full cure is such that sufficient flow of the resin can be achieved. Flow of the resin is important, for example, in a case where the structure of a pressing element is to be copied on the surface of the wear layer. This requires a displacement of the acrylic resin in all relief parts of the pressing element.

In the case of the aforementioned benzoyl peroxide and / or lauryl peroxide, with 0.5 to 2 parts per hundred parts of acrylic resin within an economically acceptable time frame and with acceptable energy consumption, adequate curing while retaining sufficient flow is achieved.

Preferred embodiments which can be used in combination with the first and / or the second aspect are discussed below.

Preferably, the wear layer of the coated panel of the first and / or the second aspect comprises traces of a peroxide, such as of benzoyl peroxide and / or lauryl peroxide.

Preferably, the aforementioned wear layer is uniformly or substantially uniformly cured over its entire thickness.

Preferably, the thermal curing involves chemical cross-linking, preferably of the double carbon bonds present in the acrylate resin. Such a crosslinking reaction gives rise to extremely good wear properties.

Preferably, the aforementioned decor comprises a carrier sheet provided with plastic, such as a paper sheet. For example, it may be a printed paper of the type used for manufacturing DPL type laminate panels and / or a paper with a Gurley value of less than 30 seconds, or even less than 25 or 20 seconds. The low Gurley value is advantageous for providing the

BE2018 / 5787 said plastic to the core of the paper concerned. Preferably, the paper has a surface weight of 40 to 250 grams per square meter, more preferably between 55 and 150, or between 65 and 90 grams per square meter. The higher surface weights, namely between 90 and 150, are preferably used in furniture panels, while the lower surface weights, namely between 65 and 90 grams per square meter, are preferably used as floor panels. The printing can be obtained in an analogous manner, for example by means of an offset printing process with printing cylinders, and / or obtained in a digital manner, for example by means of an inkjet printing process, preferably in a so-called single-pass printer.

Instead of plastic-coated paper, it is also possible to use, for example, plastic foil, such as a foil of PVC (polyvinyl chloride) or PET (polyethylene terephthalate), printed or not, or veneer. It is noted that plastic films are an example of moisture-impermeable layers and that the present inventors have realized that, because no chemical moisture is formed when the acrylic resin hardens, a thermally cured wear layer, more specifically based on acrylic resin, can be formed on a plastic film or other impermeable layer. In the laminate layers of the prior art panels, the inventors assume that the chemical moisture migrates toward the substrate and, therefore, in the prior art, an impermeable layer above this substrate is undesirable.

Preferably, the plastic provided on the support sheet is a plastic comprising double carbon bonds.

According to a special embodiment, the plastic provided on the carrier sheet forms a part of the aforementioned wear layer, this part being located between the actual decor, for instance a printed pattern or a veneer, and the part of the wear layer formed by thermally cured acrylic. The portion of the wear layer formed by the plastic material of the decor may include hard particles such as alumina or silicon carbide particles.

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Preferably, the plastic provided on the support sheet is selected from the list of polyurethane, urethane-acrylic copolymer, acrylate, latex, polyether and polyester, optionally in combination with a cross linking agent, such as carbonic dimide, polyisocyanate or aziridine. The plastic in question is preferably applied to the carrier sheet in a water-based mixture or dispersion, for instance by immersion, one or more rollers and / or one or more spraying or casting applications. It is of course not excluded that the aforementioned plastic would be melamine formaldehyde. In such a case, for example, a coating is applied to the surface of the plastic-coated carrier sheet facing the wear layer, which promotes bonding with the thermosetting acrylic resin. Such a coating can include aliphatic polyurethane, latex, water-based UV-curable substance, such as water-based UV-curable acrylic resin, chemically modified melamine resin or etherified melamine resin.

Preferably, the aforementioned acrylate resin is obtained on the basis of a multifunctional acrylate or methacrylate monomer and / or oligomer, such as a hexafunctional acrylate or methacrylate oligomer. A multifunctional acrylic or methacrylate oligomer provides a hard, but possibly brittle, wear-resistant layer.

Preferably, the aforementioned acrylate resin is obtained on the basis of a monofunctional or difunctional acrylate or methacrylate monomer and / or oligomer. A difunctional acrylate or methacrylate oligomer provides a tough, or less brittle, wear resistant layer.

Acrylate monomers or oligomers are preferred, since they are more reactive than methacrylate monomers and oligomers.

Preferably said acrylic resin is of the aliphatic type. On the basis of such acrylic resin, aging and / or discoloration is maximally limited.

Preferably, the acrylate resin comprises 5 to 80 weight percent monomers, or more preferably 5 to 60 weight percent, which are monofunctional, difunctional or multifunctional

BE2018 / 5787. Monomers in the acrylic resin can produce one or more of the following effects: decrease the viscosity to the desired value, increase the adhesion by better absorption in adjacent layers, such as in the substrate, or in the decor, positively or negatively affect the reactivity, significantly affect the flexibility and / or brittleness of the obtained wear layer, set the operating range in terms of the temperature to be used, for example, positively influence the chemical resistance. For example, with a multifunctional monomer, better cross-linking, curing and chemical resistance can be achieved. For example, a trifunctional monomer such as TMPTA can be used for this. In view of the short chain length, a promotion of cross-linking and curing can also be achieved with differential monomers. For example, DPGDA (Dipropylene glycol diacrylate) monomer can be used.

In the most preferred embodiment, the aforementioned acrylate resin is obtained at least on the basis of a mixture of two or more acrylate oligomers of different functionality, preferably on the basis of a mixture of multifunctional acrylate oligomer, wherein "multi-" is considered to be more than two, and difunctional acrylic oligomer. With such a mixture, the desired hardness and toughness of the final wear layer can be adjusted.

The use of acrylic resin as a wear layer also allows the admixture of acrylates with special properties. For example, the aforementioned acrylate resin can be obtained at least with a chemically modified acrylate, such as with a fluoracrylate. With the addition of chemically modified acrylates to the acrylic resin, properties such as water repellency, ease of maintenance, anti-fingerprint (anti-fmgerprint), anti-microbial properties can be achieved. Other possible additives to the acrylate resin are metallic pigments and materials that improve the haptic interaction. The additives mentioned here have little or no influence on the thermal curing of the acrylic resin.

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Preferably at least hard particles such as aluminum oxide particles or silicon carbide particles are added to the acrylic resin. According to an alternative, the aforementioned hard particles are located between the aforementioned decor and the part of the wear layer formed by the acrylic resin. In the case of a decor comprising a plastic-coated backing sheet, the aforementioned hard particles may be in a layer formed by the respective plastic. Preferably at least 5 grams or at least 10 grams per square meter of such hard particles are added. Such particles can further increase the wear resistance. The particles preferably have a so-called mesh size F100 or are smaller, but preferably not smaller than mesh size F320. The latter corresponds approximately to an average particle size between 30 and 125 micrometers. The wear resistance of the obtained wear layer can also be adjusted, whether or not in combination with the presence of hard particles, by its thickness. Preferably, the wear layer obtained on the basis of the thermosetting acrylic resin has at least a thickness of 50 microns, and preferably at least 100 microns.

Preferably, the aforementioned wear layer is obtained on the basis of 10 to 300 grams per square meter of the aforementioned acrylic resin. In the case of a furniture panel, the wear layer is preferably obtained from 10 to 30 grams per square meter of the acrylic resin, while, in the case of a floor panel, the wear layer is preferably obtained from 30 to 160 grams per square meter of the acrylic resin.

Preferably, the coated panel of the invention is a floor panel, preferably suitable for floating installation. The wear layer can exhibit a particularly high wear and / or scratch resistance, but is also soft enough to achieve an important sound improvement compared to traditional melamine surfaces.

Preferably, the coated panel has a relief on its surface. Preferably, the relief also shows gloss differences. These gloss differences can occur in zones with at least two respective gloss levels, these gloss levels being clearly distinguishable by the user and thus with the naked eye. More special

BE2018 / 5787 it is preferred that for the aforementioned zones respectively at least two gloss levels are used, which are chosen such that certain zones manifest themselves clearly as matte zones, while other zones manifest as non-matte or glossy zones. The most matte areas on the clad panel, e.g. floor panel, preferably exhibit a gloss level of 10 or better less than 10, while the less matte or glossy zones have a gloss level of more than 10, and better still more than 20, all this measured according to DIN 67530. Regardless of the absolute gloss levels used, the difference in gloss between the matt and glossy zones of the coated panel is preferably at least 10.

For the same purpose as in the first and second aspects, the present invention relates, according to an independent third aspect, to a method for manufacturing coated panels, wherein the panels have at least one substrate and a top layer applied thereon and the above-mentioned top layer decor and a transparent or translucent wear layer, characterized in that the method comprises at least the following steps:

the step of applying an acrylic resin containing a thermo-initiator to the aforementioned decor; and

the step of at least partially curing the aforementioned acrylic resin by means of a heated pressing operation to form at least a part of the aforementioned wear layer. It goes without saying that for the acrylate resin and the thermo-initiator, the possibilities stated in the context of the aforementioned first and / or second aspect of the invention can be invoked. Preferably, the acrylate resin comprises at least one multifunctional acrylate oligomer and 0.5 to 2 parts of benzoyl peroxide or lauryl peroxide as a thermal initiator per 100 parts of acrylic resin. By curing under pressure, maximum use is made of the possibilities of the thermosetting acrylic resin. It is clear that the aforementioned instant dual cure system can also be used here.

Preferably, the aforementioned pressing operation is carried out on the basis of a so-called Kurztakt press or single-daylight press. It is, of course, not excluded that a continuous type press, preferably a press, would be used

BE2018 / 5787 uses moving press belts, between which the whole to be pressed moves. It is also possible to work with a continuous type press using one or more press cylinders, which are preferably textured. The invention is of particular importance in texturing wear layers by means of press cylinders. In fact, in such a technique, the residence time under pressure is short, and a fast thermosetting acrylic resin can sufficiently take over the structure of the pressing element even during such a short residence time.

Preferably, the aforementioned pressing operation is carried out at a temperature of 70 to 220 ° C and / or at a pressure of 5 to 80 bar. The inventors have achieved good results when pressed in a Kurztakt press at 195 ° C and 40 bar (about 40 kg / cm ² ), for 22 seconds. Such process parameters correspond to those used in the pressing of melamine-based laminate panels. However, such high temperatures and high pressures are not necessary in the compression molding of the thermosetting acrylic resin, and the process parameters can be adjusted in a wide range, more specifically lowered until the desired effectiveness is achieved.

Preferably, the aforementioned pressing operation is carried out with the aid of a structured pressing element, such as with a structured pressing plate, for instance of the type known per se from WO 2009/043910.

Preferably, a so-called frame or frame is used in the pressing operation, which extends along all edges of the material to be pressed. The purpose of such a frame or frame is to prevent any splashing of the acrylic resin from the press when the pressure builds up. In addition, the choice of thickness of the frame or frame makes it possible to set the exact desired thickness of the wear layer. The frame or frame additionally ensures that sufficient pressure is exerted on the curing acrylic resin.

According to a special embodiment, the method of the invention further comprises the step of post-curing the pressed wear layer by means of ultraviolet and / or

BE2018 / 5787 electron radiation, both preferably under inert atmosphere. According to an important example of the present particular embodiment, a surface can be achieved with relief and / or gloss differences, similar to the structures that can be achieved in a melamine surface, but with the quality and sound properties of an electron beam cured surface. To this end, the pressed wear layer, which is structured on the basis of a pressing element, can be post-cured by means of electron radiation under an inert atmosphere.

Preferably, the aforementioned pressing operation is performed on a stack comprising at least the substrate, the decor and the acrylic resin. In doing so, a process is achieved which in many aspects corresponds to the completion of a production process for laminate panels, such that such a process can easily be fitted into an existing laminate production.

Preferably, the step of applying an acrylic resin to the aforementioned decor is performed while the decor is already part of a stack comprising at least the substrate and the decor.

Preferably, the aforementioned decor, such as the aforementioned, comprises a carrier sheet, such as a paper sheet, and the method, in such case, preferably comprises at least still the step of providing the relevant carrier sheet with plastic material. The method may further include the step of providing hard particles such as aluminum oxide or silicon carbide particles in the aforementioned plastic. This step can be put into practice in many ways, for example by mixing the hard particles in the plastic before it is provided on the relevant carrier sheet, or by applying the hard particles in the plastic after it has already been provided on the carrier sheet. , for example, by spreading the relevant particles, or by rolling up, spraying or jet-filling liquid mixtures or dispersions containing the relevant particles.

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Preferably, the step of providing the relevant carrier sheet with plastic comprises at least applying a water-based or a water-based UV-curable plastic to the above-mentioned carrier sheet.

Preferably, the step of providing the relevant carrier sheet with plastic comprises at least applying a UV-curable substance, for instance an acrylate resin, this substance further comprising a thermo-initiator.

As aforementioned, the plastic provided on the carrier sheet preferably further contains hard particles such as corundum particles, i.e. aluminum oxide particles.

It is clear that the method of the third aspect is preferably used to manufacture the coated panels from the first and / or the second aspect and / or the preferred embodiments thereof.

It is clear that the coated panels of the first and second aspects and / or obtained according to the third aspect can have different structures. Some important options are listed below, without wishing to be exhaustive.

According to a first possibility, the coated panel comprises a wood fiber board as substrate, a plastic-coated printed paper sheet as decor, and the wear layer of the invention.

According to a second possibility, the coated panel comprises a substrate consisting of plastic or plastic composite, more particularly of thermoplastic plastic or composite. This could be a substrate based on filled PVC (polyvinyl chloride), PP (polypropylene), PET (polyethylene terephthalate), PU (polyurethane). The filler may include calcium carbonate or talc or other powder or dust, such as wood particles, bamboo particles, and / or other vegetable particles. In the case of PVC, it can be rigid, semi-rigid or soft PVC, namely with a plasticizer content per hundred parts of PVC of respectively less than 5, between 5

BE2018 / 5787 and 15, or more than 15. The filler content can vary widely and can amount to 80 or 85% by weight of the plastic composite. The decor can for instance comprise a print performed on a plastic foil, for instance on a PVC foil. According to the invention, the wear layer then contains at least a part obtained on the basis of a thermally cured acrylic. It is clear that the wear layer may comprise other parts, such as a transparent plastic film, for example a transparent PVC film, which is then preferably located under the part which is covered by the thermally cured acrylic. This embodiment makes it possible to provide sharp relief characteristics and excellent surface properties on the surface of a panel consisting mainly of thermoplastic plastic.

According to a third possibility, the coated panel comprises a substrate which is cured at least partly together with the part of the wear layer formed from acrylic resin and preferably furthermore a decor. The substrate can for instance be formed on the basis of a textile layer, woven or non-woven, for example a so-called spunbound non-woven layer, such as a textile layer based on glass fibers, steel fibers and the like, which is preferably provided with thermosetting plastic, such as thermosetting acrylic resin. It is possible to form a clad panel of this third possibility in one step by pressing a stack with the plastic coated textile layer, the decor, and the wearing layer in a heated press. In this way, an extremely thin but stable panel can be obtained, such as a panel with a thickness of less than 4 millimeters, or even 2 millimeters or thinner.

According to a fourth possibility, the coated panel comprises a substrate and a wear layer according to the invention, but the decor is formed by the surface of the substrate. This may be the case, for example, with decorative board materials such as wood board materials, for example for application of the invention in solid parquet, or oriented strand boards (OSB).

According to a fifth possibility, the top layer is formed as above in one of the first to fourth possibilities, but the substrate is formed by fiber cement board, magnesium oxide based board, polyolefin based board,

BE2018 / 5787 wood chip board, OSB, filled soft PVC board, filled hard or rigid PVC board, foamed plastic board, preferably so-called closed-cell foamed plastic board, a multilayer board, such as a plywood board or a plastic-based board with both layers of soft PVC and layers from hard PVC or rigid PVC.

For the same purpose as in the first through third aspects, according to an independent fourth aspect, the present invention relates to a further coated panel having at least one substrate and a top layer applied thereon, the aforementioned top layer comprising at least one decor, having as characterized in that between the aforementioned decor and the substrate there is a thermally cured acrylic resin and / or that the decor is formed at least partly by a thermally cured acrylic resin. Thus, in this fourth aspect, the coated panel does not necessarily have a wear layer. If this were the case, the wear layer concerned would not necessarily have been obtained on the basis of thermally cured acrylic resin. The inventors have determined that the presence of a thermally cured acrylic resin at any position in the top layer can improve tap sounds and other surface properties. Of course, the acrylic resin and / or thermo-initiators employed in the context of the fourth aspect may be the same as those mentioned in the first to the third aspect, provided that they do not necessarily serve as a translucent or transparent layer to lead.

Preferably, the aforementioned decor comprises at least one support sheet, such as a paper sheet, wherein the thermally cured acrylic resin forms the connection between the aforementioned support sheet and the substrate. It is clear that the paper sheets from the previous aspects can be used for this.

Preferably, the thermally cured acrylic resin is colored in the fourth aspect, for example in that it comprises pigments, such as titanium oxide. In such a case, the invention may relate to a white panel, which can be used per se as furniture panel, or which can be used as a semi-finished product

BE2018 / 5787 used in a method in which the white layer serves as a printing surface for a printing still to be carried out.

Preferably, the thermally cured acrylic resin forms a base layer for a printing carried out thereon, which at least partly forms the aforementioned decor.

According to an alternative embodiment, the aforementioned decor is a veneer, the thermally cured acrylic resin preferably extending from the underside of the veneer into and / or through pores, cracks and other openings of the veneer. As mentioned above, the acrylic resin is preferably colored. In this way, the acrylic resin on the surface of the veneer at openings such as nuts and cracking can form a colored fill.

In the context of the previous four aspects, it is also noted that for the substrate use can be made of a wood fiber board, such as an MDF or HDF board. According to a special embodiment, a fiberboard with a low density is used, namely with an average density of less than 750 kg per cubic meter, or even of 650 kilograms per cubic meter or lower. The use of a plate of such low density contributes to further improve the sound, for example the tapping sound, when using the coated panel, especially in cases where these panels are used as floor panels in a floating installation. The use of such low density fibreboards has been made possible in part by the lower residual tensile stresses in the surface of the panels from the foregoing aspects. Namely, there is a more limited risk that tensile stresses in the top layer would lead to raised top edges. Usually, in the prior art laminate panels, such a phenomenon is prevented or limited by increasing the density of the board. With the top layer of the panels of the present invention, this is no longer necessary.

According to a special embodiment, use is made of a substrate which is free from unbound formaldehyde or which is free from formaldehyde. This could, for example, be a wood fiber board bonded using pMDI glue

BE2018 / 5787 (polymeric methylene di-phenyl diisocyanate). When the top layer is therefore free of formaldehyde, for instance mainly built up on the basis of paper and thermosetting acrylic resin and / or polyurethane, a completely formaldehyde-poor or formaldehyde-free coated panel is obtained.

It is further noted that the invention in all its aspects, individually, allows the aforementioned top layer to comprise a water-impermeable layer. This has been made possible by the fact that the thermosetting acrylic resin, unlike melamine formaldehyde, does not produce so-called “chemical” water as a by-product in the polymerization. In the case of the molding or curing of melamine resin, it is important that this chemical water can escape either to the substrate or to the surface, and water-impermeable layers are an obstacle to be avoided in such a case. Preferably, said water impermeable layer is formed by a layer present between said decor and the substrate. In this way, any moisture present on the surface of the coated panel cannot penetrate into the substrate and a very dimensionally stable panel can be obtained with varying humidity. This is interesting, for example, in cases where the aforementioned substrate comprises or consists of a wood fiber board. Alternatively, said water-impermeable layer is formed by an ink layer that at least partially forms the aforementioned decor. Still other examples of water-impermeable layers are TPU (thermoplastic polyurethane) films, polyester-based layers, aluminum films, in particular non-perforated aluminum film, and the like. In all these embodiments, the dimensional stability of the coated panels can be increased.

In general, it is noted that the present invention, in all its aspects, is particularly useful for use in coated panels whose decor includes a print based on UV cured inks. UV cured inks, as set forth in WO 2014/024100, can form a strong barrier to the aforementioned chemical water of a melamine polycondensation reaction, leading to a variety of undesirable effects on the surface of the panels. The current

BE2018 / 5787 invention prevents or limits the formation of chemical water by the use of a thermally curing acrylic resin in the top layer.

It is clear that the wear layer in the context of the present invention is seen as the full layer between printed decor and the surface of the panel. Furthermore, it is clear that this wear layer is preferably essentially or even completely built up on the basis of the aforementioned thermally cured acrylic resin. However, it is not excluded that the wear layer on the surface of the panel still comprises a superficial coating and / or that a part of the wear layer is formed by plastic originally applied to a support sheet of the decor, as mentioned above.

According to a special embodiment, the aforementioned wear layer comprises a material sheet, such as a paper sheet. Such a material sheet significantly contributes to the impact resistance of the floor panel and reduces the risk of cracking of the usually hard, but brittle wear layer. The material sheet makes the wear layer more ductile, which is also interesting when subsequently machining the edges of the floor panel. The ductility of the wear layer reduces the risk of splintering edges when milling any coupling means. Moreover, such a material sheet forms a barrier against the movement of any wear-resistant or hard particles in the still wet wear layer during production, so that these particles can be more effective in the obtained floor panel. In the most preferred embodiment thereof, the wear layer comprises a material sheet comprising hard particles embedded per se. This may be, for example, a so-called Mead overlay, for example as described in US 5,820,937, in which an alpha cellulose paper is filled during production with aluminum oxide particles or other wear-resistant particles. In such an embodiment, the hard particles are pre-eminently held at a fixed position in the thickness of the wear layer, moreover, no special measures should be taken to keep the hard particles in suspension in the lacquer layer or other material of the wear layer. The latter leads to a reduced risk of loss of transparency due to the use of any suspending agents and to a smoother production process. Also when machining the edges there is less risk of the hard particles being peeled off, as these are held together somewhat in the material sheet.

BE2018 / 5787

As mentioned above, the coated panel of the invention is preferably a floor panel, especially intended for floating installation. Preferably, the floor panel is further characterized in that it is provided with mechanical coupling parts on at least two opposite edges and that these coupling parts in a coupled condition of two such floor panels provide a clamping effect of the top edges, in particular of the wear layers, against each other at the respective edges. With such an embodiment a certain watertightness of the edges can be obtained. This is important, for example, in cases where the substrate uses a porous and / or wood-based substrate, for example in the case of MDF or HDF.

According to a special embodiment, the above-mentioned substrate is provided on at least two opposite edges with a coating or impregnation which prevents or limits the penetration of moisture into the substrate. In the case of a coating, it is preferably overlapped with the edge of the top layer. In other words, according to this embodiment, a moisture-resistant coating is provided at the edge of the floor panel, said coating extending from the substrate to at least over the boundary with the above-mentioned top layer. Preferably, the covering extends further, at least beyond the boundary with the decor and / or with the wear layer.

In cases where a low-density fibreboard, namely with a density of less than 750, or less than 650, kilograms per cubic meter, is used for floor panels with mechanical coupling means, measures are preferably taken to increase the quality of the material on the edges of the substrate. For example, a reinforcement or impregnation with MDI or PU can be applied to the edges. Another possibility is to apply an acrylic resin to these edges, which is then preferably cured by means of electron radiation. This curing can optionally be obtained together with the UV or electron beam post-curing discussed above. Preferably, the acrylic resin to be applied to the edges is a layer of viscous acrylic resin. Another

BE2018 / 5787 another possibility is the application of urea formaldehyde (UF), melamine formaldehyde (MF) or another resin for the pressing operation at least in those places where the coupling agents will eventually be formed. Furthermore, the substrate can be impregnated from below with PU or MDI. In the most common click systems, for example that of WO 97/47834, it is important that the bottom region of the plate, namely where the bottom groove lip of a lockable tongue-in-groove connection is located, is solid.

As mentioned above, the wear layer is preferably provided with a structure or relief formed by depressions on the surface thereof. Preferably, this structure contributes to the imitation of the pattern depicted in the printed decor and / or the structure forms a demarcation of the printed decor, for example on at least one edge thereof. For example, in the case of a wood imitation, it is possible to work with indentations in the form of wood tracks and / or veins. According to another example, it is possible to work with a demarcation of the decor in the form of chamfers or other chamfers. In the case of stone decor, a structure can be used that mimics the presence of cement joints. As mentioned above, the invention allows such structure or relief to be formed with deep depressions, for example with depressions of 400 microns or deeper. For example, chamfers or other chamfers can be formed with a depth of 400 micrometers.

Preferably, the wear layer is provided with structural parts that extend into the substrate, or, in other words, that the decor and the underlying substrate are also structured. Such an embodiment is particularly interesting in the realization of structural parts such as chamfers, because in this way, despite the limited thickness of the wear layer, they can still be made deep. The relief obtained in the decor itself also contributes to the panel's faithful imitation.

According to a variant, the invention according to one or more of its preceding aspects relates to a decorative profile instead of a coated panel. It's possible

BE2018 / 5787, for example, concerns the type of profile that is used for finishing a floor covering, such as a transition profile, end profile, plinth or the like. This variant provides for a smooth production of profiles that match with decorative panels, for example in particular matching with the previously mentioned coated panels. According to the present variant, the invention can lead to a decorative profile of floor quality that can be produced in a simpler manner, and thus creates more freedom for the design of such profiles.

For example, the acrylic resin used in the various aspects of the present invention may have the following composition:

5 to 80 weight percent monomers, or better yet 5 to 60 weight percent, which may be monofunctional, difunctional or multifunctional, preferably selected from the list of cyclic monofunctional monomers (CTFA (cyclic trimethylol-propane formal acrylate), TMCHA (trimethylcyclohexyl acrylate) , TBCHA (4-tert-butylcyclohexyl acrylate), IBOA (isobomyl acrylate), THFA (tetrahydrofurfuryl acrylate), ...), alkoxylated monofunctional monomers (PE4A, ...), alkane monofunctional monomers (EOEOEA (2- (2ethoxyethoxy)) ethyl acrylate)), alkoxylated difunctional monomers, alkyl difunctional monomers, multifunctional monomers (TMPTA (trimethylolpropantriacrylate), GPTA (propoxylated glyceryl triacrylate), PET (T) A (pentaerythritol tri- (tetra-) acrylate), ...), acid based adhesion promoter monomers;

- 0.1 to 10 weight percent of additives such as defoamers, leveling agents;

- 0.1 to 30% by weight of nano-silica or corundum (A12O3);

- 5 to 80 weight percent oligomers of polyester acrylate, urethane acrylate, polyether acrylate, melamine acrylate, polycarbonate acrylate, epoxy acrylate, amine modified acrylate or urethane (meth) acrylate, preferably a urethane acrylate of the formula AIPIA, where * A - Acrylic or methacrylic, mono or polyfunctional »I - Isocyanate (aliphatic - monomeric or oligomeric - di- or multifunctional)

BE2018 / 5787 • P - Polyol - long or short chain - polyester, polyether, polycarbonate, di or multifunctional;

- optional fillers, pigments and / or reinforcing agents;

0.1 to 5 weight percent thermo initiator, preferably organic peroxide or azo polymerization initiator.

It is also noted that the use of urethane acrylate has the additional advantage that hydrogen bridges are present, which leads to a good ratio between flexibility and hardness of the layer concerned. It is also possible to work with or with the addition of so-called “Specialty high functionality urethane acrylates”, for example with silicone-based, hydrophobically functional or fluorinated acrylates.

With the insight to better demonstrate the features of the invention, some preferred embodiments are described below, by way of example without any limitation, with reference to the accompanying drawings, in which:

Figure 1 shows in perspective a coated panel, more particularly a floor panel, with the features of the invention;

Figure 2 shows a cross-section on a larger scale along the line II-II shown in Figure 1;

Figure 3 schematically represents some steps in a method with the features of the invention;

Figures 4 and 5 show results of noise measurements on a panel with the features of the invention; and

Figure 6 illustrates another method with the features of the invention.

Figure 1 shows a coated panel 1. In this case it concerns a rectangular floor panel that comprises a substrate 2 and a top layer 3 applied to it with at least a decor 4 and a transparent or translucent wear layer 5. The wear layer 5 comprises a thermally cured acrylic resin, whereby the curing is achieved by hand

BE2018 / 5787 of a thermally initiated radical cross-link reaction. For this purpose, a mixture of acrylic resin and a thermo-initiator has been used.

The floor panel 1 is suitable for floating installation and for this purpose is provided, in this case, on the long pair of edges 6-7 and on the short pair of edges 8-9 with mechanical coupling means 10 which allow two such floor panels 1 at their respective edges. 6-7-8-9 together.

Figure 2 clearly shows that at least the long pair of edges 6-7 of the floor panel 1 of Figure 1 is provided with mechanical coupling means 10 mainly in the form of a tooth 11 and a groove 12, in the coupled state of two such floor panels 1 at these edges 6-7 a locking between the relevant tongue 11 and groove 12 is created both in a first direction R1 perpendicular to the plane 13 of the coupled panels 1 and in a second direction R2 perpendicular to the coupled edges 6-7 and in the plane 13 of the panels 1.

Preferably, on the short edges 8-9, as is the case in the embodiment of figures 1 and 2, mechanical coupling means 10 are also provided which provide a locking in corresponding directions, mainly or not in the form of a tooth 11 and a groove 12.

For the embodiment of Figure 2, use was made of a substrate 2 comprising a wood fiber board with a density of 750 kilograms per cubic meter or less. In order to improve the bonding strength of the coupling means 10 present, the substrate 2 is impregnated at its edges 6-7 with MDI (methylene diphenyl diisocyanate) 14. As mentioned above, it is particularly important that at least the bottom lip 15 flanking the groove 12 sufficiently sturdy. The impregnation or other reinforcement of the substrate material 2 near the top edges 16 is also desirable to limit possible swelling due to penetrating and / or printing effects during the milling of the coupling means 10.

BE2018 / 5787

In the example, a bottom layer 18 is also provided on the underside 17 of the panel 1. It is also made from a thermally cured acrylic resin and its main purpose is to form a barrier to any rising moisture. As explained in the invention, the wear layer 5 exhibits a low level of residual stresses, so that the backsheet 18 hardly functions as a balancing layer. The counter-layer 18 can therefore also be omitted, certainly in the cases where the substrate 2 itself consists of waterproof material and / or has a water-resistant bottom 17 and / or has been treated to be water-resistant to at least the bottom 17 of the substrate 2. , for example because the substrate material is impregnated with MDI on the underside 17.

The decor 4 of the floor panel 1 of Figures 1 and 2 comprises a carrier sheet provided with plastic 19, more particularly a paper sheet 20 with a surface weight of approximately 70 grams per square meter. The paper sheet 20 has a print 21 in the form of a wood motif. The plastic 19 used comprises double carbon bonds and is more especially polyurethane.

Figure 3 schematically shows some steps in a method of manufacturing the floor panel of Figures 1 and 2.

The example starts from a decor 4 comprising at least one paper sheet 20. The paper sheet 20 is in itself provided with a printing 21. In a first step S1, the paper sheet 20, more specifically a paper web from which the paper sheet 20 will later be obtained by cutting, is provided with plastic material 19. For this purpose, the paper web is unrolled and impregnated into the core by means of a first plastic material 19. The core impregnation can limit the risk of splitting of the paper sheet 20 in the final coated panel 1. In the example, this core impregnation takes place in two sub-steps, namely a first sub-step SI A in which plastic 19 is applied on the basis of a roller 22, and a second sub-step S1B in which the paper sheet 20 is immersed in a bath 23 with the relevant plastic 19. . In the example, the plastic 19 which is applied in the first sub-step S1 A and in the second sub-step S1B is the same. However, it is also possible that the plastic

BE2018 / 5787 applied in the first and the second sub-step are different from each other, regardless of the concrete application technique that is used. Between the first sub-step SI A and the second sub-step S1B, the paper sheet 20 performs a path 24 which allows sufficient penetration of the first plastic 19 applied during the first sub-step SI A. As stated in the introduction, the first plastic material 19 can use modified melamine formaldehyde resin, modified urea formaldehyde resin or modified melamine urea formaldehyde resin. Preferably, the first plastic 19 comprises double carbon bonds. Preferably, the first plastic 19 is selected from the list of polyurethane, urethane-acrylic copolymer, acrylate, latex, polyether and polyester.

Figure 3 further shows that, after the aforementioned core impregnation, aluminum oxide particles can be applied in a third sub-step SIC, for example, as here, by a spreading operation. This is followed in a fourth sub-step S1D, preferably by a drying operation in a warm air oven 25. Optionally, in a fifth sub-step SIE, on the side of the printing 21 and / or the side of the paper sheet 20 which is intended for the wear layer 5, an interlamellar coating 26 is applied which increases compatibility with the wear layer 5 formed from thermosetting acrylic resin. Such an interlamellar coating can for instance consist of a water-based polyurethane coating, a water-based UV-curing substance and / or carbon-dimide. During the same step SIE, or in a separate step, a coating 27 may also be applied to that side of the paper sheet 20 intended to face the substrate 2. The purpose of such a coating 27 is to achieve a better adhesion with the substrate 2. Alternatively, such a coating 27 may also have the purpose of effecting a sound insulation. In the latter case, use is preferably made of polyurethane, for example aromatic polyurethane or thermoplastic polyurethane (TPU). After the application of the interlamellar coating 26 and / or the coating 27, a drying operation similar to that of the fourth sub-step S1D can be carried out again, as in the example.

BE2018 / 5787

In a seventh sub-step S1F, the treated paper sheet 20 in this example passes through a cooling roll 28, and the paper web is divided into sheets.

In a second step S2, a stack 29 is formed comprising at least the substrate 2 and the decor 4, the decor 4 in this case comprising a printed paper sheet 20 provided with plastic material 19, obtained in step S1.

The method of the invention comprises at least the third step S3 shown, namely the step of applying an acrylate resin containing a thermo-initiator to the decor 4, and the fourth step S4 shown, namely the step of at least partially curing the the aforementioned acrylic resin by means of a heated pressing operation. In the third step S3, an acrylic resin with a thermo-initiator is also applied to the bottom 17 of the substrate 2, to form a counter layer 18. It is clear that here the third step S3, namely the step of applying to the decor 4 the acrylic resin is applied while the decor 4 is already part of a stack 29 comprising at least the substrate 2 and the decor 4.

In the example shown, the pressing operation is performed on the basis of a so-called kurztakt press 30, and more specifically on the basis of a structured pressing element 31 or press bleach. The pressing operation is carried out on a stack 29 comprising the substrate 2, the decor 4, the acrylic resin of the wear layer 5 and the counter layer 18. During the pressing operation, the structure 32 of the pressing element 31 is copied into the surface of the wear layer 5.

Figure 4 shows the results, represented by curves 33-34, of sound measurements taken, on the one hand, on a melamine surface of a prior art floor panel (curve 33), and, on the other hand, on a thermally cured acrylic surface of a floor panel according to the invention (curve 34). It concerns measurements of the loudness in telephone (English: loudness in phon), shown in ordinate 35, as a function of the frequency (Hz), shown in abscissa 36, of a scratch made by means of a metal pin on the relevant surface. The loudness is a quantity that objectively represents the subjectively perceived sound level. With the results

BE2018 / 5787 in curve 33 for the melamine surface, a very large and wide peak can be observed in the frequency interval 1000 to 5000 Hz, where the human ear is most sensitive. This sound is perceived as irritating by users. When the same scratching is performed on the thermally cured acrylic surface, a significantly lower absolute loudness can be seen in the same interval in the results in curve 34. This leads to a perception of a warmer and less high sound that is comparable to the sound achieved on a wooden surface.

Figure 5 shows the results, represented by curves 37-38, of sound measurements taken, on the one hand, on a melamine surface of a prior art floor panel (curve 37), and, on the other hand, on a thermally cured acrylic surface of a floor panel according to the invention (curve 38). The prior art floor panel comprises a substrate of HDF, namely fiberboard with an average density of about 950 kilograms per cubic meter. The floor panel according to the invention comprises a substrate of MDF, more particularly a wood fiber board with an average density of about 650 kilograms per cubic meter. The results shown are measurements of the loudness in phone (English: loudness in phon), shown in ordinate 35, as a function of the frequency (Hz), shown in abscissa 36, of a tapping sound made by means of a metal pin on the relevant surface. The results show that the tapping noise on the floor panel of the invention is less loud and that peaks in the 1000 to 5000 Hz interval disappear. This achieves a warmer and more woody sound.

Figure 6 shows another method of manufacturing a coated panel 1 with the features of the invention. In this case it concerns a method for manufacturing a floor panel 1 with a substrate 2 of plastic or plastic composite, for example a floor panel of the type LVT (luxury vinyl tile) containing a substrate 2 of highly filled soft, semi-rigid or rigid PVC. The substrate 2 can be formed by extrusion of the respective plastic or the relevant composite, or, as here, in a first step T1, formed by one or more spreading operations in which granules 39 or powders of a suitable composition are deposited on a conveyor belt 40 and consolidated between

BE2018 / 5787 the belts 41 of a double belt press. A printed plastic film 42 can be unwound on the formed substrate 2 in a second step T2 to form the decor 4, and, in a third step T3, an optional transparent plastic film 43 can be unwound to form at least a portion 5A of the wear layer 5. In a fourth step T4, a mixture of at least acrylic resin and thermo-initiator is applied to the obtained whole, preferably on the transparent plastic film 43, for instance by means of one or more rollers 44. The substrate 2, the one or several plastic films and the mixture of acrylate resin and thermo-initiator are then consolidated in a fifth step T5, or cured by means of a heated roller 45. In the example shown, a structured roller is used. The structure 32 of the roller 45 is copied extremely well in the thermally curing acrylic resin. Such a method leads to a wear layer 5 with excellent aesthetic and mechanical properties, without the need for an additional superficial UV-cured lacquer layer, as is the case with prior art LVT floor panels.

As an alternative to the method shown in figure 6, the mixture of acrylate resin and thermo-initiator can also be applied on a semi-consolidated or unconsolidated product comprising a substrate of plastic or plastic composite and at least one decor, for example on a semi-product with a substrate, printed plastic film and possibly a transparent plastic film above the print. The whole of semifinished product and mixture can then be pressed in a Kurztakt press similar to the press 30 shown in step S4 of figure 3.

It is clear that the method shown and mentioned in the introduction can per se be performed in whole or in part on larger panels, slabs, or continuous webs. In such a case, the actual coated panels are obtained at least after the division of the relevant panels, slabs, or webs.

The present invention is by no means limited to the above-described embodiments, but such coated panels and methods for the

Manufacturing thereof BE2018 / 5787 can be realized without departing from the scope of the present invention. Furthermore, it is also possible to apply the concepts of the invention in texturing packaging materials, or flat materials, such as posters, stationery or laminating material for laminating profiles, such as skirting boards and finishing profiles for floor coverings. The invention therefore also relates to a method for manufacturing packaging materials or flat materials, characterized in that the method comprises the step of applying to the actual packaging material or flat material, for example to the paper, cardboard, plastic foil, plastic , applying a thermally curable acrylic resin, for example with a thermo-initiator, and at least partially curing the above-mentioned acrylic resin by means of a heated pressing operation, in which preferably a structured pressing element or foil is used. It is clear that such a method can further exhibit the preferred features of the invention according to the third aspect without necessarily obtaining coated panels.

Claims (38)

Conclusions: 1 .- Coated panel with at least one substrate (2) and a top layer (3) applied thereto, the above-mentioned top layer (3) comprising at least a decor (4) and a transparent or translucent wear layer (5), characterized in that the aforementioned wear layer (5) comprises a thermally cured acrylic resin. Coated panel according to claim 1, characterized in that said acrylic resin is cured by means of a thermally initiated radical cross-link reaction. Coated panel according to claim 1 or 2, characterized in that said curing comprises at least a cross linking of the double carbon bond present in the acrylate resin. Coated panel, whether or not according to any one of the preceding claims, with at least one substrate (2) and a top layer (3) applied to it, wherein said top layer (3) has at least one decor (4) and a transparent or translucent wear layer (5), characterized in that the aforementioned wear layer (5) is obtained on the basis of a mixture of acrylate resin and a thermo-initiator. Coated panel according to claim 4, characterized in that said thermo-initiator is an organic peroxide, preferably benzoyl peroxide or lauryl peroxide. Coated panel according to claim 4 or 5, characterized in that the aforementioned mixture comprises 0.1-5 parts thermoinitiator per 100 parts acrylate resin, and preferably 0.5-2 parts thermoinitiator per 100 parts acrylate resin. Coated panel according to one of the preceding claims, characterized in that the aforementioned wear layer (5) comprises traces of a peroxide. BE2018 / 5787 Coated panel according to any one of the preceding claims, characterized in that the aforementioned wear layer (5) is uniformly or substantially uniformly cured over its entire thickness. Coated panel according to any one of the preceding claims, characterized in that the thermal curing comprises chemical cross-linking, preferably of the double carbon bonds present in the acrylate resin. Coated panel according to any one of the preceding claims, characterized in that said decor (4) comprises a carrier sheet provided with plastic (19), such as a paper sheet (20). Coated panel according to claim 10, characterized in that the said plastic (19) comprises double carbon bonds. Coated panel according to claim 10 or 11, characterized in that the said plastic (19) is selected from the list of polyurethane, urethane-acrylic copolymer, acrylate, latex, polyether and polyester, optionally in combination with a cross linking agent. Coated panel according to any one of the preceding claims, characterized in that the aforementioned acrylic resin is obtained at least on the basis of a multifunctional acrylic monomer and / or oligomer, such as a hexafunctional acrylic oligomer. Coated panel according to any one of the preceding claims, characterized in that the aforementioned acrylate resin is obtained at least on the basis of a monofunctional or difunctional acrylate monomer and / or oligomer. BE2018 / 5787 Coated panel according to any one of the preceding claims, characterized in that said acrylic resin is obtained at least with a chemically modified acrylate, such as with a fluoracrylate. Coated panel according to any one of the preceding claims, characterized in that the coated panel (1) is a floor panel, preferably suitable for floating installation. Coated panel according to one of the preceding claims, characterized in that the coated panel (1) has a relief on its surface, possibly with gloss differences. Coated panel according to any one of the preceding claims, characterized in that the aforementioned acrylic resin is of the aliphatic type. 19 .- Method for the production of coated panels, wherein the panels (1) have at least one substrate (2) and a top layer (3) applied thereon and the above-mentioned top layer (3) has at least a decor (4) and a transparent or translucent wear layer (5), characterized in that the method comprises at least the following steps: - the step (S3) of applying an acrylic resin containing a thermo-initiator to the aforementioned decor (4); and - the step (S4) of at least partially curing the aforementioned acrylate resin by means of a heated pressing operation to form at least a part of the aforementioned wear layer (5). Method according to claim 19, characterized in that the pressing operation is carried out on the basis of a Kurztakt press (30). Method according to claim 19 or 20, characterized in that the pressing operation is carried out at a temperature of 120 to 220 ° C and / or at a pressure of 10 to 80 bar. BE2018 / 5787 Method according to any one of claims 19 to 21, characterized in that the method further comprises the step of post-curing the pressed wear layer (5) by means of Ultra-Violet and / or electron radiation, preferably under an inert atmosphere . Method according to any one of claims 19 to 22, characterized in that the aforementioned pressing operation is performed using a structured pressing element (31). Method according to any one of claims 19 to 23, characterized in that the aforementioned pressing operation is performed on a stack (29) comprising at least the substrate (2), the decor (4) and the acrylate resin. Method according to any one of claims 19 to 24, characterized in that the step (S3) of applying an acrylic resin to the aforementioned decor (4) is performed while the decor (4) is already part of a stack (29). ) comprising at least the substrate (2) and the decor (4). Method according to any one of claims 19 to 25, characterized in that the aforementioned decor (4) comprises a carrier sheet, such as a paper sheet (20), and the method comprises at least the step of providing with plastic (19) the relevant carrier sheet. Method according to claim 26, characterized in that the step of providing the respective carrier sheet with plastic (19) comprises at least applying a water-based or a water-based UV-curable plastic to the above-mentioned carrier sheet. Method according to claim 26 or 27, characterized in that the step of providing the respective carrier sheet with plastic material (19) at least applying BE2018 / 5787 comprises a UV curable substance, this substance further comprising a thermoinitiator. A method according to any one of claims 19 to 28, wherein the method is used for manufacturing panels (1) having the features of any one of claims 1 to 18. 30.- Coated panel with at least one substrate (2) and a top layer (3) applied to it, wherein the aforementioned top layer (3) comprises at least one decor (4), characterized in that is located between the aforementioned decor (4) and the substrate (2) is a thermally cured acrylic resin and / or that the decor (4) is at least partly formed by a thermally cured acrylic resin. Coated panel according to claim 30, characterized in that the thermally cured acrylic resin is colored, for example in that it comprises pigments, such as titanium oxide. Coated panel according to claim 30 or 31, characterized in that the thermally cured acrylic resin forms a base layer for a printing carried out thereon, which at least partly forms the aforementioned decor. Coated panel according to any one of claims 30 to 32, characterized in that the aforementioned decor is a veneer, the thermally cured acrylic resin preferably extending from the underside of the veneer into and / or through pores, cracks and other openings of the veneer. Coated panel according to any one of claims 30 to 33, characterized in that the aforementioned decor comprises at least one carrier sheet, such as a paper sheet (20), the thermally cured acrylic resin forming the connection between the above-mentioned carrier sheet and the substrate (2) . BE2018 / 5787 Coated panel or method according to one of the preceding claims, characterized in that for the substrate (2) use is made of a wood fiber board with an average density of less than 750 kg per cubic meter. 5 Coated panel or method according to one of the preceding claims, characterized in that the above-mentioned top layer (3) comprises a water-impermeable layer. Coated panel or method according to claim 36, characterized in that said water-impermeable layer is formed by a layer present between said decor (4) and the substrate (2). Coated panel or method according to claim 36, characterized in that said water-impermeable layer is formed by an ink layer which at least partly forms the aforementioned decor (4).