BE1019351A5 - PANEL AND METHODS FOR MANUFACTURING PANELS. - Google Patents

Abstract

Panel of the type comprising at least one substrate and a top layer touched to this substrate, wherein said top layer comprises a motif printed directly on the substrate and a transparent or translucent plastic layer applied above the said printed motif, characterized in that the said transparent or translucent plastic layer contains vinyl and is placed between the printed design and the vinyl-containing top layer and primer.

Description

Panel and methods for manufacturing panels.

This invention relates to panels and methods for manufacturing panels.

More specifically, the invention relates to panels of the type at least composed of a substrate and comprising a top layer applied to this substrate, said top layer comprising a printed design and a transparent or translucent plastic layer applied above the aforementioned printed design. This may, for example, concern furniture panels, ceiling panels, floor panels or the like which mainly consist of an MDF or HDF (Medium or High Density Fiberboard) base panel or substrate and a top layer applied thereto. According to a first possibility, it concerns panels obtained by means of a method in which one or more material layers are applied to the substrate, wherein at least one of these material layers is applied by means of a printing which is carried out directly on the substrate, wherein this printing then forms at least a portion of the aforementioned printed motif. According to a second possibility, it concerns panels obtained by means of a method in which one or more material layers are applied to the substrate, wherein at least one of these material layers comprises a printed material sheet, wherein the printing of the material sheet then at least a part of the aforementioned. printed motif.

The panels, manufactured according to the aforementioned first possibility, are known per se, for example from US 1,971,067 or DE 195 32 819 A1. It is also known from the aforementioned documents that said material layers may comprise one or more primer layers, wherein these primer layers extend substantially under the aforementioned printing, and / or may comprise one or more finishing layers substantially extending above the aforementioned printing. Such finishing layers may comprise, for example, transparent or translucent plastic layers, which form a protective layer above the printed decor and may contain, for example, wear-resistant particles such as aluminum oxide. It is not excluded that this protective layer contains a material sheet, such as a paper sheet.

The state of the art in relation to panels which are provided with printing directly on the substrate is furthermore apparent from, inter alia, WO 01/48333, WO 02/00449, WO 2004/042168, EP 1454 763, DE 197 25 829 C1 and DE 10 2004 009 160 A1.

It is known, inter alia from WO 01/48333, that either lacquers or synthetic resins can be used to realize the aforementioned layers of material. In the case of synthetic resins, these are applied via a carrier sheet which is previously provided with such synthetic resin and is provided on the substrate on the basis of a heated press. For example, in the case of lacquers, UV curing lacquers can be used. Each time wear-resistant particles are also used to achieve a sufficient wear resistance on the surface of the panel. Such wear-resistant particles, however, lead to a reduced transparency of the relevant material layer.

It is known, inter alia from DE 197 25 829 C1 or EP 1 454 763, that one or more liquid-applied synthetic resins can be used for realizing said material layers. After these resin layers have been dried, they are cured in a heated press. Paper-free top layers can be realized on the basis of such a method. According to the prior art, adhesion of synthetic resins is only possible on water-based inks. However, the water-based inks are less resistant to UV radiation, as a result of, for example, sunlight, than UV-borne inks.

Panels manufactured according to the aforementioned second possibility for this are known, for example, from WO 97/47834 and WO 01/96689. Such panels typically comprise a top layer applied over the substrate on the basis of thermosetting resin, wherein this top layer is assembled from resin-coated paper sheets by means of a pressing operation. One of these paper sheets is usually provided with a printed design, while another paper sheet is transparent and serves as a protective layer for this printed design. During the aforementioned pressing operation, a relief can also be realized in the surface of the above-mentioned transparent or translucent layer.

The present invention, according to its various independent aspects, aims in the first place to offer alternative panels and methods which, according to various preferred embodiments thereof, can be carried out smoother and / or more economically than the methods of the prior art. According to various embodiments thereof, the panels of the invention also exhibit mechanical or optical properties which represent an advance over the panels known from the prior art. For example, panels can be achieved that lead to a more acceptable sound when used as floor panels and / or to a more pleasant, warmer feeling.

To this end, the invention according to its first independent aspect relates to a panel of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising a motif printed directly on the substrate and a transparent or translucent plastic layer above the aforementioned printed motif is provided, characterized in that the above-mentioned transparent or translucent plastic layer contains vinyl and that a primer is applied between the printed design and the vinyl-containing plastic layer. Preferably, said translucent plastic layer consists essentially of vinyl and / or plasticizer. Because vinyl is used on the surface, a pleasant feeling is created on the surface of the panels. Said primer allows an adhesion to be obtained economically from the vinyl-containing plastic layer to an underlying layer, for example on the inks of the printed design. The inventors have found that such adhesion can be obtained both from UV-based inks and from water-based inks. Preferably, no further substances and / or layers are present between the inks of the printed design and the vinyl-containing plastic layer.

The vinyl-containing plastic layer preferably has a thickness of at least 0.2 millimeter or more. The inventors have found that such a thickness of the plastic layer allows an acceptable wear resistance to be obtained even if the panel of the invention were to be used as a floor panel. Moreover, such a layer exhibits good transparency. With such a thickness of the vinyl-containing plastic layer, the use of wear-resistant particles such as aluminum oxide particles, which are normally used in floor panels, can be omitted in this layer. Such wear-resistant particles have a negative influence on the transparency of the plastic layer and a limitation of the amount of such particles leads to a better representation of the aforementioned printed motif. Preferably, in the case wear-resistant particles are used, less than 10 or even more preferably less than 5 grams per square meter of such particles are used. The invention does not, of course, preclude that a larger amount of such particles would be used in the vinyl-containing plastic layer.

Preferably, the thickness of said vinyl-containing plastic layer is less than 1 millimeter. Such a thickness leads to a highly wear-resistant surface layer which is sufficient in most cases and yet still sufficiently transparent.

A very interesting value for the thickness of the aforementioned vinyl-containing top layer, which offers an optimum between cost and wear resistance, is in the range of 0.25 to 0.5 millimeter. With such a thickness, additional wear-resistant particles are not necessary.

It is noted that, according to the invention, one or more further layers can be applied above the aforementioned vinyl-containing plastic layer. The combined thickness of these further layers is preferably smaller, and more preferably at least 5 times smaller than the thickness of the vinyl-containing plastic layer. Said further layers may comprise, for example, UV-cured layers, which may, for example, lead to an increased resistance to the formation of black stripes emitted by shoe soles. It is not excluded that said one or more further layers comprise wear-resistant particles which lead to an increased scratch resistance. This may, for example, concern alumina or silica particles with an average diameter that is smaller than 60 micrometres, and more preferably smaller than 10 micrometres. It is also not excluded that these further layers are free from such wear-resistant particles or at least still comprise less than 10 grams or less than 5 grams per square meter of such particles.

Preferably, a primer is used which comprises a polymer with an aliphatic character or is mainly based on such a polymer. The inventors have found that polymers with an aliphatic character, compared to polymers of an aromatic character, exhibit a much lower tendency to yellowing and can therefore guarantee better transparency of the aforementioned vinyl-containing plastic layer. Of course, it is not excluded that within the idea of the invention a primer based on aromatic polymers would be used. In such a case, UV blockers and / or brighteners are preferably also used in the primer and / or the vinyl-containing plastic layer disposed thereon. As a whitening agent, for example, a substance can be used which contains a derivative of a distyryl biphenyl compound.

Preferably said primer contains polyurethane and / or polyisocyanurate or the primer is based on one or both of these polymers. As mentioned above, it preferably concerns the aliphatic variant of these substances. The inventor has established that polyurethane or polyisocyanurate economically achieves good adhesion between a vinyl-containing plastic layer and the inks of a printed motif. For example, it may be UV-supported inks or water-based inks.

Preferably, said transparent or translucent plastic layer is free from material sheets, such as paper sheets or plastic sheets or films. Such sheets have a negative influence on the transparency of the layer in question, moreover they mean an extra cost.

As aforementioned, the aforementioned transparent or translucent plastic layer is preferably free of additives that increase the wear resistance of the panel, or at least still contains less than 10 grams per square meter of such additives.

The aforementioned vinyl, which forms at least partially the transparent or translucent plastic layer, preferably relates mainly to polyvinyl dichloride (PVdC). PVdC is generally more expensive than PVC (polyvinyl chloride), but shows a lower water permeability. Water resistance is a desirable property for many decorative surfaces, such as floor panels or furniture panels. The invention does not exclude the use of vinyl which mainly concerns polyvinyl chloride.

According to a variant, a more environmentally friendly panel can be obtained if the aforementioned vinyl is at least partially and preferably mainly or exclusively a chlorine-free vinyl compound, preferably selected from the list of polyvinyl butyral, polyvinyl alcohol and vinyl acetate, such as EVA (ethylene vinyl acetate).

Preferably, said vinyl-containing plastic layer, and more preferably the entire top layer, is plasticizer-free or contains up to 35 parts by weight plasticizer per 100 parts by weight of vinyl compound or more preferably less than 20 parts by weight. Limiting the level of plasticizers leads to a stronger surface, which exhibits a better impact resistance. Moreover, the largely omission of plasticizers is interesting in the manufacture of such panels, since the risk of the formation of harmful substances, such as vapors, is thus limited. When plasticizer is used, for example, phthalate-based plasticizers can be chosen, such as DINP (di-isononyl phthalate). In such a case, however, it is preferable to use plasticizers based on isosorbide. These last plasticizers are more environmentally friendly.

According to a different variant, the aforementioned plastic layer contains polyurethane instead of vinyl, said polyurethane preferably being aliphatic, and preferably being so-called polyester-based thermoplastic polyurethane. The inventors have found that the use of such a plastic layer gives rise to a good scratch resistance on the surface of the panels. In addition, polyurethane has better resistance to soiling through shoe soles than vinyl. An additional UV-based surface layer to limit or prevent this phenomenon is therefore unnecessary in the case of a polyurethane-containing plastic layer. The polyurethane plastic layer thus preferably forms a transparent or translucent layer which is present on the actual surface of the panel. Preferably, the thermoplastic polyurethane layer or film has a thickness between 0.1 and 0.3 mm, or several of such layers or films have a joint thickness between 0.1 and 0.3 mm. Such a thickness is sufficient to obtain a wear resistance that is acceptable for floor panels. Thicker layers are of course not excluded, since they can lead to an even higher wear resistance. The inventors have determined that a thickness of 0.15 mm allows a Taber IP value (EN 13329) of 3000 or more to be achieved. This value can be achieved even when the plastic layer is free from additional wear-resistant particles. When an aromatic polyurethane is used, use is preferably also made of a UV blocker or whitener, such as a substance comprising a derivative of a distyryl biphenyl compound. The inventors have also established that for carrying out pressing operations on a polyurethane-containing plastic layer, for example with a metal pressing pad, no additional measures must be taken for the release of the pressing pad and the plastic layer. It is clear that the other preferred embodiments of the first aspect of the invention, mutatis mutandis, can be used in combination with a polyurethane-containing plastic layer.

It is noted that the above deviating variant is generally regarded as a particularly independent aspect of the invention, which can also be defined as a panel of the type comprising at least one substrate and a top layer applied to this substrate, said top layer being a printed design and comprises a transparent or translucent plastic layer which is arranged above the aforementioned printed design, characterized in that the aforementioned transparent or translucent layer contains polyurethane. It is clear that, as in the first aspect, the printed motif can be formed directly on the substrate, or can be applied to a carrier material such as a paper sheet or a plastic film, preferably a polyurethane film. Furthermore, it is clear that, according to this particularly independent aspect, a primer is not necessarily used.

Preferably, the aforementioned motif is applied directly to the substrate with the intervention of one or more primer layers. The use of base layers is known per se from the patent documents mentioned in the introduction. Preferably said primers are based on UV lacquers, synthetic resins such as melamine formaldehyde resin and / or vinyl. In the latter case, the above-mentioned chlorine-free or non-chlorinated vinyl compounds can be used. A printing base of uniform or quasi-uniform color is preferably obtained on the basis of the aforementioned primer layers.

The aforementioned motif is preferably printed on the basis of UV-supported inks. Such inks exhibit good UV stability. In addition, the primer and the vinyl-containing plastic layer permit the use of such UV inks.

According to the first aspect of the invention, said vinyl-containing plastic layer is preferably applied to the panel as a liquid or pasty substance, which after drying is dried or cured, for example by means of ovens, presses and / or radiators, for example infrared lamps. The heat from heated elements can also be used for drying out or hardening, this heat being directly or indirectly supplied to the aforementioned liquid substance. For example, the panel can be transported for this purpose over one or more heated rollers. The liquid or pasty substance preferably relates to a so-called plastisol which comprises at least one vinyl compound, preferably PVC, suspended in a plasticizer. The plasticizer relates, for example, to a phthalate compound, such as di-isononyl phthalate (DINP), and can form 50 percent by weight or more of the suspension or paste.

The application of the aforementioned liquid or pasty substance can, for example, be carried out by applying it directly to the printed substrate, for example by means of an iron-on device. According to another possibility for this, the liquid substance or paste is first applied to a carrier material, and then transferred to the printed substrate, wherein the aforementioned carrier material may or may not be transferred. When the carrier material is co-transferred on the substrate and retained therein in the final panel, which is not necessary, it is preferably a carrier material that is or becomes transparent or translucent. For example, use can be made of a transparent or translucent plastic film, for example on the basis of a vinyl compound, such as PVC.

Alternatively, said vinyl-containing plastic layer or a portion thereof can also be applied as one or more vinyl-containing plastic films. According to the aforementioned deviating variant, the polyurethane or a part thereof can also be applied to the substrate as one or more films. It is clear that this alternative and this deviating variant can be combined with a portion of the plastic layer that is applied in liquid form.

According to a preferred embodiment of the invention, the panel of the invention has a relief on the surface thereof, said relief extending in the vinyl-containing plastic layer, but preferably the recesses of the above-mentioned relief are only so deep that they are not in the above-mentioned printed motif. Use can be made of any technique for applying such relief. Use is preferably made of a technique in which the structure of a structured press element is copied into the surface of the vinyl-containing plastic layer, for example by means of a pressing operation. Preferably, said plastic layer is heated prior to and / or during the pressing operation. By heating up the plastic layer, the plastic layer is preferably made softer, so that the pressing operation can be realized at a lower pressure. In the case of prior heating, use is preferably made of a radiation source, such as an infrared radiator. In the case of heating during the pressing operation, heating is preferably carried out by means of thermal oil with which the pressing device and the pressing element are heated. Preferably, said plastic layer is forced-cooled during pressing and / or afterwards. By cooling, the structure on the surface of the plastic layer is better preserved. A temperature of 130 ° C or more is preferably achieved during the pressing operation. For the aforementioned cooling, use can be made of the same pressing operation or use of a separate operation and pressing device, which is then preferably not heated, or even optionally cooled. It is also possible that the above-mentioned structured pressing element is only used during this cooling, and / or that in this case only an adhesion between the different layers of the panel is obtained during the first pressing operation. Said cooling assumes that the consolidated panel is still hot from the first pressing operation and / or is reheated before being subjected to the second pressing operation.

It is preferable to use an open-and-close discontinuous press or a so-called cork-stroke press, whereby one package of a substrate, printed design and plastic layer is compressed per cycle. It is also possible to work with so-called multi-level presses, whereby multiple packages can be compressed per cycle.

According to a second independent aspect, the invention relates to a panel of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising a vinyl-based plastic layer, characterized in that the said substrate is preferably a wood-containing or a wood-based substrate and that a primer is provided between the substrate and said vinyl-based plastic layer. Preferably, there are no further substances or layers between the substrate and said primer and / or between said primer and said vinyl-based plastic layer.

Preferably, a polyurethane-containing substance is used as primer, such as a polyurethane-based dispersion glue. This primer preferably provides the bond between the aforementioned plastic layer and the substrate and, even better, no further bonding means are provided for this purpose.

Preferably, said vinyl-based plastic layer relates to a vinyl film, for example a PVC film. This may be a decorative film which has a printed pattern. It can also be a transparent foil or possibly a colored foil. Preferably, said vinyl-based plastic layer relates to at least one decorative film which is printed by means of solvent inks. A very high printing quality can be achieved with solvent inks. According to a deviating variant of the second aspect, use is made of a polyurethane-containing plastic layer such as a thermoplastic polyurethane foil. For this purpose, preferably the materials are used which are mentioned in the deviating special aspect of the first aspect. Of course, the preferred embodiments of the second aspect can also be implemented on the basis of such a polyurethane-containing plastic layer instead of a vinyl-containing plastic layer.

According to a particular embodiment, said vinyl-based plastic layer comprises both a transparent or translucent vinyl-based film and a vinyl-based decorative film, said transparent or translucent vinyl-based film being applied above said decorative film.

According to yet another special embodiment, said vinyl-based plastic layer comprises both a vinyl-based decorative film and a transparent or translucent vinyl-based layer that is free of films and other sheets. This transparent or translucent vinyl-based layer can be obtained as described with reference to the first aspect of the invention, for example by applying the liquid substances or pastes mentioned therein.

It goes without saying that also according to this second independent aspect, the surface of the panel, more particularly the vinyl-based plastic layer, can be provided with a relief in any way. Preferably, one or more of the options mentioned in the first aspect are used for this.

According to a third independent aspect, the present invention relates to a method for manufacturing a panel, wherein this panel is of the type comprising at least one substrate and a top layer applied to this substrate, characterized in that the method comprises at least the following steps: the step of preparing the substrate; the step of performing printing on the substrate; the step of applying a primer to the printing; and the step of applying a vinyl or polyurethane-containing substance to the substrate.

The vinyl or polyurethane-containing substance which is applied to the substrate according to the third aspect can be located anywhere in the final top layer of the panel. It may, for example, form part of a layer that serves as a base layer for the printing and / or form part of a transparent or translucent plastic layer that is located above the printing. Preferably, the vinyl or polyurethane-containing substance is at least in the aforementioned transparent or translucent plastic layer and the aforementioned primer at least partially realizes the bond between the print and this transparent or translucent plastic layer.

Said step of preparing the substrate may involve, for example, a sanding operation, and / or the application of one or more primers. Said primer layers preferably consist of lacquers or synthetic resins, with which preferably at least one uniform printing ground is realized. The aforementioned primer layers are preferably applied and dried out in liquid or viscous form, for example as a paste. For this purpose, one or more rolling devices, or ovens or other heating devices, are preferably used.

As aforementioned, said primer layers may also comprise vinyl-containing substances, and for example consist essentially of the possibilities mentioned in the first aspect for the material of the vinyl-containing plastic layer, in which case they do not necessarily have to result in a transparent or translucent layer, but preferably result in a uniform, for example white or beige, printing soil.

As primer, preferably one of the primers described on the basis of the first aspect is used. For the vinyl-containing material, the materials which are mentioned in the first aspect are preferably used as possibilities for the transparent or translucent plastic layer.

Said step of performing a printing is preferably carried out on the basis of a digital printing device, for example on the basis of an inkjet printer. UV-supported inks are preferably used herein. Water-based inks or solvent inks are of course not excluded.

It is clear that the method of the third aspect is primarily intended for manufacturing the panels of the first aspect or the deviating variant or special aspect of the first aspect mentioned therein, and that preferred embodiments of these aspects or variants give rise to corresponding preferred embodiments of the third aspect.

According to a fourth independent aspect, the invention further relates to a method for manufacturing a panel, wherein this panel is of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising at least one plastic film, characterized in that the method comprises at least the step of applying said film to the substrate by means of a pressing operation at an elevated temperature. The purpose of the pressing operation can be two-fold. Namely, this purpose may include applying the film to the substrate and applying structure to the surface of the top layer.

The method of the fourth aspect preferably further comprises at least the step of applying a primer to the substrate, preferably a polyurethane dispersion glue.

It is self-evident that the method of the fourth aspect is primarily intended for manufacturing the panels of the second aspect and that preferred embodiments of the second aspect give rise to corresponding preferred embodiments of the fourth aspect.

The plastic film used is preferably a PVC film or a thermoplastic polyurethane film. This foil can either be printed and form the printed pattern, if any, of the panel, or be transparent or translucent and thus form a protective layer over such optional pattern. In the case of polyurethane, use is preferably made of the aliphatic variant or of an aromatic variant which then preferably contains UV blockers and / or whiteners. For examples of whitener, reference is made to the aforementioned aspects and variants, the relevant materials of which can be taken over there for use in this fourth aspect.

Preferably, the aforementioned substrate is a wood-containing or wood-based substrate, such as MDF or HDF or wood chip board. According to a variant, the aforementioned substrate comprises a foamed plastic, such as foamed polyethylene or foamed polyvinyl chloride.

In general, the aforementioned substrate is preferably a porous substrate, as is the case with the aforementioned substrates. On the basis of such a substrate, a good resistance to delamination, or in other words to the release of the top layer, can be achieved. In principle, it is sufficient if the surface of the aforementioned substrate, which is provided with the top layer, is porous. However, it is not excluded that the entire substrate is porous.

The aforementioned top layer preferably comprises at least two plastic films, for example a decorative film and a transparent film. This could possibly be airtight films. In that case, measures are preferably taken to prevent air inclusions between the two plastic films. For example, one or both of the plastic films can be perforated, such that any accumulated air can escape along these perforations.

The method of the fourth aspect preferably comprises a step which is carried out prior to the step of the pressing operation, wherein in this preceding step said two plastic films are laminated to a composite film. In this way the logistics of the process become easier. In the case of airtight films, this way some air inclusions are already avoided prior to the pressing operation. The lamination preferably takes place on the basis of a calendar device or another device in which rollers are used. By means of rollers, the air can gradually be expelled from between the aforementioned plastic foils.

According to a special embodiment, the top layer comprises at least one paper sheet which is provided with thermoplastic plastic, such as PVC, polyisocyanate or polyurethane, and at least one plastic film, such as a thermoplastic polyurethane film or a PVC film, at least the substrate, said paper sheet and said plastic film are interconnected by means of the pressing operation of the fourth aspect. Preferably, the aforementioned paper sheet relates to a printed paper sheet, wherein the printing provides a printed design in the top layer of the panel. In such a case, the plastic film preferably forms a protective layer above the printed design. The paper sheet and the plastic film are preferably bonded together in a separate processing step by means of a calendar device or another device in which rollers are used. This separate processing step preferably takes place prior to the pressing operation.

Preferably, said pressing operation is carried out at a temperature between 80 ° C and 150 ° C, or more preferably between 110 ° C and 140 ° C. Such a temperature is sufficient for achieving an adhesion of the plastic films over the primer with the substrate. It is preferable to use an open-and-close discontinuous press or a so-called cork-stroke press, in which one package of a substrate and one or more plastic films is compressed per cycle. It is also possible to work with so-called multi-level presses, whereby multiple packages can be compressed per cycle.

Preferably, said pressing operation is performed with a pressing time of less than one minute. The inventors have determined that such pressing time is sufficient to achieve good adhesion. At the same time, it is possible to provide a structure in the surface of the panel on the basis of the pressing operation, in particular in the aforementioned plastic film. According to a preferred embodiment, the starting point is at least one flat, unstructured plastic film, preferably a transparent or translucent plastic film, which in the aforementioned pressing operation is both adhered to the substrate and provided with a structure. To realize the above-mentioned structure, use is preferably made during the pressing operation of a structured press element, for example a structured press blank or press plate. Preferably, said structure is carried out in accordance with a printed motif, for example the motif of the optional decorative foil. The structure is preferably obtained in a pressing operation performed in an open-and-close press. The aforementioned pressing element is preferably provided with a coating which promotes the release of the pressing element from the panel.

For the quality of the structure obtained, it may be desirable for the aforementioned package to be cooled under pressure. To this end, use can be made of the same pressing operation in which the top layer is adhered to the substrate, or use can be made of a separate pressing device, which is then preferably not heated, or even optionally cooled. It is also possible that the above-mentioned structured pressing element is only used during this cooling, and / or that in such a case only an adhesion between the different layers of the aforementioned package is obtained during the first pressing operation. Said cooling assumes that the consolidated package is still hot from the first pressing operation and / or is reheated before being subjected to the second pressing operation.

According to a fifth independent aspect, the invention further relates to a method for manufacturing a panel, wherein this panel is of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising at least one printed motif and a transparent top applied over it. or translucent plastic layer, characterized in that the method comprises at least the step of applying a vinyl-containing paste over the printed motif to form at least a portion of said transparent or translucent plastic layer, and of applying by means of a pressing operation a relief in the aforementioned transparent or translucent plastic layer. The paste used herein preferably relates to a so-called plastisol or a suspension of PVC in plasticizer. It is clear that the pasta mentioned in other aspects can be used for this purpose.

According to a preferred embodiment, the aforementioned paste is applied over a plastic foil or layer of plastic which is provided with the aforementioned printed motif. This is preferably a printed PVC or polyurethane foil. In the case of a polyurethane foil, it is preferably a thermoplastic polyurethane foil of the aliphatic type or of the aromatic type, wherein in the latter case preferably also UV blockers and / or plasticizers are applied in the top layer, preferably at least at a place where these UV blockers or brighteners are located in and / or above this foil. For examples of thermoplastic polyurethane foils and brighteners, reference is made to the other aspects. The printing is preferably carried out on the basis of solvent inks. Alternatively, UV-supported inks can be used.

According to a first particular embodiment of the above preferred embodiment, the plastic layer, which according to the fifth aspect over which the paste is provided, comprises at least one backing layer and a plastic film, the printed motif being applied to the plastic film, and wherein said backing layer and printed plastic film is preferably prior to the step of applying the paste. Said backing layer preferably consists of PVC, preferably recycled PVC and is preferably filled with chalk. Such a backing layer preferably makes up at least 30% and more preferably at least 45% of the thickness of the top layer. The layer obtained on the basis of the paste preferably forms at least 10 percent and more preferably at least 15 percent of the thickness of the top layer. A good thickness for this layer is a thickness of 0.2 millimeters or more. Preferably the thickness of this layer is less than 0.5 millimeter.

According to a second special embodiment of the above preferred embodiment, which can optionally be combined with the aforementioned first special embodiment, the plastic film over which the paste is applied is web-shaped. The application of the paste is then preferably effected in run-through, while the plastic film is supplied, for example, from a roll. In such a case, the aforementioned pressing operation can optionally be carried out on the basis of a continuous pressing device. However, the web provided with the paste is preferably divided into sheets which are then subjected to the pressing operation in this form. In the latter case use is then preferably made of the above-mentioned open-and-close pressing devices.

The total thickness of the top layer is preferably between 1 and 3 millimeters, and more preferably between 1.5 and 2.5 millimeters.

The layer that is realized by means of the paste is preferably free of wear-resistant particles, such as aluminum oxide. If such particles are nevertheless present, they preferably exhibit a concentration of less than 10, and more preferably of less than 5 grams per square meter.

Preferably, the top layer or the portion thereof comprising the printed design is applied to the substrate after said paste has been applied over the printed design. This leads to a smoother process. The pressing operation of the fifth aspect, which forms the relief, is preferably carried out after the substrate and the plastic layer provided with the paste have already been brought together. The top layer is preferably adhered to the substrate by means of a pressing operation, which may or may not correspond to the pressing operation that realizes the relief. According to an alternative, the pressing operation of the fifth aspect, which forms the relief, is carried out before the substrate and the coated plastic layer are brought together, or at least before they are adhered to each other. In the latter case the adhesion can be obtained by a pressing operation and / or by an adhesive connection. Preferably, however, use is made of an adhesion by means of the materials of the top layer and the substrate itself, i.e. without the intervention of external adhesive layers.

Preferably, said paste is cured or gelled at least partially before the pressing operation. It is clear that this curing takes place while the paste has already been applied to the aforementioned motif.

Preferably, by means of the aforementioned pressing operation, heat is also supplied to the aforementioned transparent or translucent layer, which optionally comprises uncured paste. The step of curing or gelling can therefore possibly be achieved at least partially on the basis of the pressing operation of the fifth aspect. When the paste is at least partially or even completely gelled before the start of the pressing operation, it is possible that the hardening can again at least partially neutralize this hardening, or in other words the transparent or translucent plastic layer recoils is made.

Preferably, said transparent or translucent layer is formed mainly on the basis of said paste. Optionally, one or more further layers, for example UV-cured layers, can be applied to the surface of the panel of a similar type as explained with reference to the first aspect.

According to a sixth aspect, the invention further relates to a panel of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising a printed motif, a paper sheet and a transparent or translucent plastic layer, characterized in that the aforementioned paper sheet comprises is of thermoplastic plastic and the aforementioned transparent or translucent plastic layer contains thermoplastic plastic. It is clear that the above-mentioned transparent or translucent plastic layer is herein preferably situated above the printed motif. Reference is made, inter alia, to the special embodiment of the fourth aspect mentioned above, which gives an example of the invention according to this sixth aspect.

The plastic that is applied to the paper sheet preferably relates to a polyurethane or a polyisocyanate. The plastic is preferably provided by soaking the paper sheet in such plastic or, on the other hand, impregnating it with it. The paper sheet provided with the thermoplastic plastic according to the invention preferably relates to a printed paper sheet which represents the aforementioned printed motif. According to an alternative, the paper sheet can also be a transparent paper sheet which is arranged as a protective layer above the aforementioned printed motif. In such a case, the printed design can either be applied to a separate material sheet or be printed directly on the substrate, with or without the intervention of primers.

The plastic of the above-mentioned transparent or translucent plastic layer preferably relates to a vinyl compound or a polyurethane. Preferably, a thermoplastic polyurethane film is used, for example of the types still mentioned in previous aspects.

Preferably both the paper sheet provided with the plastic and the transparent or translucent plastic layer are applied to the substrate by means of a calendar device.

According to a seventh aspect, the present invention further relates to a panel of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising a printed design and a transparent or translucent plastic layer which is arranged above said printed design, with characterized in that the top layer is made up of at least one layer containing a thermosetting synthetic resin and at least one layer containing a thermoplastic plastic. As thermosetting synthetic resin, polycondensation resins, such as melamine resins, can be used. As a thermoplastic plastic, use can be made of a vinyl compound or a polyurethane.

The layer that relates to the thermosetting resin is preferably a decorative paper provided with such a resin. The decorative paper then exhibits at least a portion of the aforementioned printed motif. The thermosetting resin layer is preferably located directly against the substrate. On the basis of this thermosetting resin, the bond with the substrate can be achieved, namely preferably without external glue connections.

The layer containing the thermoplastic plastic preferably comprises at least one transparent or translucent layer which is arranged above the printed design, and thus preferably above the layer with the thermosetting resin. In this way a surface layer with special properties can be obtained. When said thermoplastic plastic layer has a thickness between 0.1 millimeter and 0.5 millimeter, even without additional wear-resistant particles, a wear resistance can be obtained that is acceptable for floor coverings or floor panels. For a good quality, a thickness of 0.25 to 0.4 is desirable. It is of course not excluded that such a layer would be made thicker than 0.5 millimeter.

According to a first possibility, the layer containing the thermoplastic plastic can be applied at least partially as a liquid or pasty substance. For this, reference is made to the examples in other aspects. According to a second possibility, the layer containing the thermoplastic plastic can be at least partially provided as a material sheet provided with such a plastic, for example a paper sheet. For this, reference is made to the examples in other aspects, more particularly the sixth aspect. According to a third possibility, the layer containing the thermoplastic plastic can be at least partially provided as a plastic film, for example a PVC film or a polyurethane film. For this, reference is made to the examples of such films in other aspects.

In all aspects, a porous substrate such as a wood-based substrate is preferably used. The substrate can be chosen, for example, an MDF or HDF (Medium Density Fiberboard or High Density Fiberboard) or a wood chipboard. Other possible substrates are substrates comprising foamed material, such as a substrate comprising foamed polyethylene or polyvinyl chloride. The substrate preferably has a density of less than 800 kilograms per cubic meter and more preferably less than 500 kilograms per cubic meter, these lowest densities being preferably achieved on the basis of the aforementioned substrates containing foamed matter.

According to all aspects, the present invention relates to floor panels or other panels which are per se rigid and therefore cannot be rolled up per se. The final panel preferably has a thickness of more than 5 millimeters, but preferably of less than 15 millimeters. A good value for the thickness is 7 to 10 millimeters. Such panels lend themselves well to the provision of mechanical coupling means which allow two or more of such panels to be connected to each other at their edges. Use is herein preferably made of mechanical coupling means, such as of the type known from WO 97/47834.

Where, according to all aspects and variants, there is talk of calendaring or calendaring devices, a device is meant in which two layers are adhered to each other at least by means of rolling, and preferably by supplying heat.

It is clear that when, according to all aspects and variants, there is talk of a plastic film, it is meant that this film consists essentially of plastic and is therefore free of other materials such as paper.

It is furthermore clear that when curing or gelling of a liquid substance or paste, at least a viscosity increase of such substance or paste is indicated. In the case of a paste containing vinyl or PVC, in addition to PVC powder, preferably at least 5 to 75 weight percent plasticizer is used and so-called soft PVC is obtained after curing. Preferably, such PVC paste also contains 3 to 15 weight percent wax, such as polyethylene wax or montan ester wax, in addition to PVC powder and plasticizer. The curing or gelling step can be carried out in various sub-steps, with heat being supplied to the paste in each case, for example directly or indirectly by means of infrared heaters or by means of heated elements which are directly or indirectly in contact with the paste. The applied temperatures at the surface of the paste are preferably between 40 ° C and 200 ° C and more preferably between 110 ° C and 175 ° C.

It is furthermore noted that in the methods of the invention it is possible to start from the production of larger panels, from which multiple panels such as floor panels can then be obtained by division, for example by means of a sawing operation. This dividing step can take place at any time and it is not necessary that all essential steps of the respective independent aspects of the invention have already been carried out before such division takes place. This is because one or more sub-steps can be carried out on the smaller panels.

It is further noted that the features of the aforementioned aspects can be combined insofar as they are not contradictory.

The present invention is by no means limited to the embodiments described above, but such methods and panels can be realized according to different variants without departing from the scope of the present invention.

Claims (15)

Panel of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising a motif printed directly on the substrate and a transparent or translucent plastic layer applied above said printed motif, characterized in that the aforementioned printed motif transparent or translucent plastic layer containing vinyl and that a primer is applied between the printed design and the vinyl-containing plastic layer, said primer containing polyurethane or polyisocyanurate having an aliphatic character. Panel according to claim 1, characterized in that the above-mentioned transparent or translucent plastic layer is free of material sheets, such as paper sheets. Panel according to claim 1 or 2, characterized in that the above-mentioned transparent or translucent plastic layer is free of additives that increase the wear resistance of the panel, or at least still contains less than 10 grams per square meter of such additives. Panel according to one of the preceding claims, characterized in that the aforementioned vinyl is polyvinyl dichloride. Panel according to one of claims 1 to 3, characterized in that the said vinyl is a chlorine-free vinyl compound, preferably selected from the list of polyvinyl butyral, polyvinyl alcohol and vinyl acetate. Panel according to one of the preceding claims, characterized in that the above-mentioned top layer has a thickness of more than 0.2 millimeter. Panel according to one of the preceding claims, characterized in that said top layer is free of plasticizers. Panel according to claim one of the preceding claims, characterized in that the aforementioned motif is applied directly to the substrate with the intervention of one or more base layers. Panel according to one of the preceding claims, characterized in that the aforementioned motif is printed on the basis of UV-supported inks. Panel of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising a vinyl-based plastic layer, characterized in that the said substrate is a wood-based substrate and that a primer is applied between the substrate and said vinyl-based plastic layer. said vinyl-based plastic layer being a PVC film. Panel according to claim 10, characterized in that said primer is a polyurethane-based dispersion adhesive. Method for manufacturing a panel, wherein this panel is of the type comprising at least one substrate and a top layer applied to this substrate, said top layer comprising at least one printed motif and a transparent or translucent plastic layer arranged over it, characterized in that the method comprises at least the following steps: the step of preparing the substrate; the step of performing printing on the substrate; the step of applying a primer to the printing; and the step of applying a vinyl-containing substance to the substrate, wherein a vinyl-containing paste is applied over the printed motif to form at least a portion of said transparent or translucent plastic layer, and wherein by means of a pressing operation a relief in said above transparent or translucent plastic layer. Method according to claim 13, characterized in that said paste is a suspension of PVC in plasticizer. Method according to claim 13 or 14, characterized in that said paste is cured or gelled at least partially before the pressing operation. The method according to any of claims 13 to 15, characterized in that said transparent or translucent layer is formed essentially on the basis of said paste.