BE1029788B1 - PANEL AND METHODS OF MANUFACTURING A PANEL - Google Patents

Abstract

The present invention relates to a panel comprising a primary and a secondary substrate layer, an intermediate layer, and a top layer, said intermediate layer being located between said primary and secondary substrate layer, and wherein said top layer is applied to the secondary substrate layer. The intermediate layer has at least one of the following properties: the intermediate layer has a Shore A hardness which is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer; the intermediate layer has an elastic modulus that is at least 10.0% lower than the elastic modulus of the primary and/or secondary substrate layer; the intermediate layer comprises a material with a substantially open cell structure; or the intermediate layer comprises a foamed thermoplastic material or a foamed thermoset material. The present invention also relates to methods for manufacturing a panel.

Description

1 BE2021/5830

Panel and methods for manufacturing a panel.

This invention relates to a panel and methods of manufacturing a panel.

WO 97/47834 describes a floor panel for assembling a floating floor.

However, the floor panel as described herein has the disadvantage that the substrate used herein, in particular MDF or HDF (Medium Density Fiberboard or High Density

Fiberboard) is sensitive to moisture, and that the construction of such a panel gives rise to walking and/or tapping noises.

EP 1 938 963 describes a plastic floor panel for assembling a floating floor. Although the floor panel according to EP '963 is more resistant to moisture and gives less rise to tapping noises, such a floor panel has a limited stiffness and high deformability, which can cause problems when it is installed on uneven surfaces. In particular, irregularities from the substrate can migrate to the surface of the floor panel (telegraphy) and/or local loads such as table or chair legs can cause a permanent deformation (indentation) in the surface of the floor panel.

EP 3 405 346 describes a plastic floor panel which has good moisture resistance and improved stiffness and lower deformability, which is advantageous for minimizing telegraphy and/or indentation. The floor panel as described in

However, EP '346 again gives rise to acoustic discomfort, in particular an increase in walking and/or tapping noises.

The invention therefore aims in the first place to provide an alternative material, in particular a panel, whereby, according to various preferred embodiments, a solution can be obtained for the problems related to walking and/or tapping noises of known panels. Some embodiments envisage

2 BE2021/5830 also improves the stiffness of these panels, minimizing and/or counteracting adverse effects such as telegraphy and/or indentation.

To this end, according to its first independent aspect, the invention relates to a panel comprising a primary and a secondary substrate layer, an intermediate layer, and a top layer, said intermediate layer being located between said primary and secondary substrate layer, and said top layer being applied to the secondary substrate layer. , and wherein the intermediate layer has at least one of the following properties: - the intermediate layer has a Shore A hardness which is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer; - the intermediate layer has an elastic modulus which is at least 10.0% lower than the elastic modulus of the primary and/or secondary substrate layer; - the intermediate layer comprises a material with a substantially open cell structure; or - the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material.

In the light of the present invention, the term "panel" denotes a sheet-like material, which sheet-like material can occur both in cut, for example cut to size, and in non-cut form. In particular, reference is made here to, among others, Luxury Vinyl Tiles (LVT), Stone Polymer Composite (SPC), or other polymer-based panels. The "top layer" as described herein may include finishing layers such as a decorative layer, a wear-resistant layer, a lacquer layer, or combinations thereof. In some embodiments, the primary and/or secondary substrate layer comprise a thermoplastic material selected from the group of polyvinyl chloride (PVC), polyethylene (PE), high-density polyethylene (HDPE), polypropylene (PP), polyester, polyethylene terephthalate (PET), polyurethane (PU) and/or elastomer. The most preferred thermoplastic material is PVC.

The intermediate layers as described herein ensure that the panels have better sound insulation. This is particularly important for panels that are

3 BE2021/5830 used as floor panels. The intermediate layers as described herein additionally and/or alternatively ensure that the panels exhibit improved walking comfort.

In some embodiments, the intermediate layer has a Shore A hardness that is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer. In the light of the present invention, the term "Shore A hardness" refers to the hardness of the intermediate layer as determined by a Type A Shore durometer. The methodology for determining Shore A hardness, as well as the specific requirements which imposed on a Type A Shore durometer are defined in the ASTM D2240 standard. Preferably, the intermediate layer has a Shore A hardness which is 11 units lower than the Shore A hardness of the primary and/or secondary substrate layer, more preferably 12 units lower, even more preferably 13, 14, 15, 16, 17, 18, 19 or 20 units lower. With increasing preference, the various embodiments as described herein further improve the sound damping and/or the walking comfort of the panels.

According to a further or other embodiment, the intermediate layer has an elastic modulus which is at least 10.0% lower than the elastic modulus of the primary and/or secondary substrate layer. The intermediate layer, and in particular the lower elastic modulus relative to the primary and/or secondary substrate layer, improves the sound-damping properties of the panel and improves walking comfort, in particular when the panel is used as a floor panel. Preferably, the intermediate layer has an elastic modulus that is at least 11.0% lower than the elastic modulus of the primary and/or secondary substrate layer, more preferably 12.0% lower, even more preferably 13.0%, 14.0% or 15.0% lower.

In some embodiments, the intermediate layer comprises a material having a substantially open cell structure. In some embodiments, the intermediate layer comprises a foamed thermoplastic material or a foamed thermoset material. These embodiments provide a panel with improved sound damping and/or improved walking comfort.

4 BE2021/5830

According to a further or other embodiment, the intermediate layer has a Shore A hardness that is 10 units lower than the Shore A hardness of the secondary substrate layer and/or the intermediate layer has a modulus of elasticity that is at least 10.0% lower than the modulus of elasticity of the secondary substrate layer. The panel herein has a relatively hard secondary substrate layer and herein provides sufficient rigidity to the panel, the relatively soft intermediate layer providing improved sound damping and/or improved walking comfort to the panel.

According to a further or other embodiment, the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material, wherein the foamed thermoplastic material or the foamed thermosetting material has an empty cell volume comprised between 10.0 and 80.0 vol.%. The empty cell volume within the range described herein is optimal for improving the sound dampening properties of the panel.

According to a further or other embodiment, said foamed thermoplastic material is selected from the group of ethylene vinyl acetate (EVA), irradiation crosslinked polyethylene (IXPE), irradiation crosslinked polypropylene (IXPP), expanded polyethylene (EPE), expanded polyethylene copolymer (EPC), polypropylene (PP), polyvinyl chloride (PVC), PVC plastisol, polyurethane (PU), or combinations thereof. These materials are optimally suited as an intermediate layer and provide the panel with improved sound-absorbing properties and/or improved walking comfort. Preferably, said foamed thermoplastic material is selected from the group of ethylene vinyl acetate (EVA), irradiation cross-linked polyethylene (IXPE), expanded polyethylene (EPE), polyvinyl chloride (PVC),

PVC plastisol, polyurethane (PU), or combinations thereof.

According to some embodiments, said primary substrate layer comprises polyvinyl chloride (PVC). Preferably, the polyvinyl chloride has a concentration of at least 95% by weight, more preferably at least 99% by weight, most preferably 100% by weight.

It is possible that the primary substrate layer further comprises one or more fillers selected from the group of inorganic fillers, such as chalk, lime and/or talc, or organic fillers, such as wood, bamboo and/or cork, or mineral fillers. According to further or other embodiments, said primary substrate layer comprises polyvinyl chloride (PVC) and calcium carbonate (CaCO3) as a filler.

In some embodiments, the calcium carbonate (CaCO:3) has a concentration of up to 80% by weight and the polyvinyl chloride (PVC) has a concentration of at least 20% by weight. Preferably, the calcium carbonate (CaCO:3) has a concentration comprised between 10 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 90% by weight.

More preferably, the calcium carbonate (CaCO3) has a concentration comprised between 60 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between and 40% by weight. It has been found that a particularly good stiffness and/or stability is achieved because the proportion of calcium carbonate is greater than the proportion of PVC. Preferably, the calcium carbonate (CaCO3) has a concentration comprised between 65 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 20% by weight. More preferably, the calcium carbonate (CaCO4) has a concentration of between 70 and 80% by weight and the polyvinyl chloride (PVC) has a concentration of between 20 and 30% by weight. Most preferably, the calcium carbonate (CaCO3) has a concentration of 75% by weight and the polyvinyl chloride (PVC) has a concentration of 25% by weight.

According to some embodiments, said secondary substrate layer comprises polyvinyl chloride (PVC). In some embodiments, the polyvinyl chloride has a concentration of at least 95% by weight, more preferably at least 99% by weight, most preferably 100% by weight.

6 BE2021/5830

Preferably, said secondary substrate layer comprises plasticizers in an amount of less than 15 phr, preferably less than 10 phr, more preferably less than 5 phr.

The various embodiments as described herein provide a secondary substrate layer that provides sufficient stability and/or stiffness to the panel.

According to a further or different embodiment, said secondary substrate layer is configured to increase the rigidity of the panel, the secondary substrate layer having at least one of the following properties: - the secondary substrate layer comprises a reinforcement layer; - the secondary substrate layer comprises calcium carbonate (CaCO3) as a filler, or - the secondary substrate layer has a thickness of at least 2.0 mm.

According to some embodiments, said secondary substrate layer comprises a reinforcement layer. A suitable reinforcing layer is, for example, a glass fiber layer. The secondary substrate layer possibly comprises alternative and/or additional reinforcement layers in order to further increase the stiffness.

According to some embodiments, said secondary substrate layer comprises calcium carbonate (CaCO 3 ) as a filler, wherein the calcium carbonate (CaCO 3 ) has a concentration of up to 80% by weight and the polyvinyl chloride (PVC) has a concentration of at least 20% by weight. Preferably, the calcium carbonate (CaCO2) has a concentration comprised between 10 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 90% by weight.

More preferably, the calcium carbonate (CaCO3) has a concentration comprised between 60 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 40% by weight. It has been found that a particularly good stability and/or stiffness is achieved because the proportion of calcium carbonate is greater than the proportion of PVC. Preferably, the calcium carbonate (CaCO:) has a concentration of between 65 and 80% by weight and the polyvinyl chloride (PVC) has a concentration of between 20 and 80% by weight.

7 BE2021/5830 35% by weight. More preferably, the calcium carbonate (CaCO2) has a concentration comprised between 70 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 30% by weight. Most preferably, the calcium carbonate (CaCO3) has a concentration of 75% by weight and the polyvinyl chloride (PVC) has a concentration of 25% by weight.

According to a further or other embodiment, the secondary substrate layer has a thickness of at least 2.0 mm, which imparts an improved rigidity and/or stability to the panel. Preferably, the secondary substrate layer has a thickness of at least 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm or 2.5 mm.

According to a further or other embodiment, said panel is provided with coupling means on at least two opposite edges, whereby a locking is effected on the relevant edges at least in a vertical direction perpendicular to the plane of the panels and/or at least in a horizontal direction in the plane of the panels and perpendicular to the edges. Thanks to the coupling means as described herein, different panels can be coupled to each other in a simple and stable manner.

Preferably, at least one of the aforementioned edges is provided with a groove, this groove being flanked by an upper lip and a lower lip, said intermediate layer extending substantially through the upper lip. More preferably, the lower surface of the upper lip is at least partially formed in said primary substrate layer. Even more preferably, said upper lip is mainly formed in the primary substrate layer, the intermediate layer and the secondary substrate layer. The embodiments as described herein have the advantage that the upper lip has excellent rigidity, so that a high-quality and durable coupling is obtained between the coupling means. Furthermore, the presence of the intermediate layer in the upper lip ensures that when connecting and/or disconnecting adjacent floor panels, the upper lip allows a slight compression and/or deformation, so that this connecting and/or disconnecting takes place efficiently, and whereby the

8 BE2021/5830 risk of permanent deformation of the upper lip, for example due to fracture, is reduced.

According to some embodiments, in a coupled condition between two adjacent panels, the intermediate layers of said adjacent panels press against each other, forming a seal along the edges of said panels. Such sealing further improves the sound-absorbing properties between adjacent panels.

According to some other embodiments, in a coupled state between two adjacent panels, the intermediate layers of said adjacent panels do not touch each other, forming a space between said intermediate layers along the edges of said panels.

According to some embodiments, the coupling means are configured to couple together the first edge of such panel to the second edge of another such panel, preferably wherein the coupling members include locking members for locking such panel coupled to its first edge at the second edge of another such panel in the direction perpendicular to the plane of the coupled panels and/or in the direction perpendicular to the coupled edges and in the plane of the panels, and wherein a coupling member is located at the first edge in the shape of a tooth and on the second edge there is a coupling part in the form of a groove, the groove being bounded by a lower lip and an upper lip, the upper lip being on the top of the panel, and the top the panel includes a first closing surface at the first edge, the distal end of the upper lip comprising a second closing surface, the first closing surface and the second closing surface being configured so that when such a panel is engaged with its first edge on the second edge of another such panel the first closing surface of such panel contacts or closely abuts the second closing surface of the other such panel.

9 BE2021/5830

The coupling means as described herein are in some embodiments provided on a first and a second opposite edge. In some embodiments, the coupling means are as described herein on a first and a second opposing edge, as well as on a third and a fourth opposing edge.

According to a further or other embodiment, said panel is a floor panel or wall panel.

According to a second independent aspect, the present invention relates to a method for manufacturing a panel, comprising the steps of: - extruding a primary substrate layer, - extruding an intermediate layer, - extruding and/or laminating a secondary substrate layer and - laminating a top layer, wherein at least the primary substrate layer and the intermediate layer are formed by means of co-extrusion.

Co-extrusion is a particularly convenient and efficient way of forming two or more interconnected layers, in particular the primary substrate layer and the intermediate layer, in addition allowing the respective compositions of the primary substrate layer and the secondary substrate layer to be differ substantially from each other.

According to a preferred embodiment, the primary substrate layer, the intermediate layer and the secondary substrate layer are formed by co-extrusion. This further simplifies the manufacture of panels and improves their efficiency.

According to another preferred embodiment, the secondary substrate layer is laminated. Lamination allows the secondary substrate layer to be efficiently attached to the assembly of the primary substrate layer and the intermediate layer in a separate process step.

10 BE2021/5830

According to some embodiments, said layers formed by co-extrusion are formed by a single die. According to some embodiments, said layers formed by co-extrusion are formed by two or more separate dies. Said molds preferably concern one or more slot-shaped molds.

According to a third independent aspect, the present invention relates to a method for manufacturing a panel, comprising the steps of: extruding a first substrate layer, laminating an intermediate layer, laminating a secondary substrate layer, and laminating a top layer, wherein at least the intermediate layer and the secondary substrate layer are laminated together on the primary substrate layer in the form of a laminated complex.

The term "laminated complex" refers to a preformed and/or offline formed complex of two or more layers, which complex can be laminated to the first substrate layer in a single step. The lamination of a laminated complex is a particularly suitable and efficient way of forming two or more interconnected layers, in particular the primary substrate layer and the assembly of the intermediate layer and the secondary substrate layer, moreover allowing the respective compositions of the individual layers differ substantially from each other.

According to some embodiments, said laminated complex is formed by the steps of: - providing the secondary substrate layer, - coating said secondary substrate layer with a foamable composition, and - foaming said foamable composition to form the intermediate layer.

11 BE2021/5830

Formation of the laminated complex by foaming a foamable composition coated on the secondary substrate layer allows the one-step formation of a foamed material, and the bonding of this foamed material to the secondary substrate layer, which is an efficient way of forming the laminated complex. More preferably, said foamable composition is foamed by heating, forming the intermediate layer. The foamable composition and/or the intermediate layer formed may comprise a PVC plastisol.

According to some embodiments, said laminated complex is formed by the steps of: - providing the secondary substrate layer, - providing the intermediate layer, and - bonding the intermediate layer and the secondary substrate layer.

Formation of the laminated complex by bonding the intermediate layer and the secondary substrate layer allows the intermediate layer and/or the secondary layer to be preformed and/or offline.

Preferably, the secondary substrate layer and/or the intermediate layer are subjected to a corona treatment prior to bonding. The corona treatment as described herein allows for improved adhesion of the intermediate layer and the secondary substrate layer, forming a well-adhered laminated complex.

According to a further or different embodiment of the second and/or third aspect of the present invention, the intermediate layer has at least one of the following properties: - the intermediate layer has a Shore A hardness which is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer; - the intermediate layer has an elastic modulus which is at least 10.0% lower than the elastic modulus of the primary and/or secondary substrate layer;

12 BE2021/5830 - the intermediate layer comprises a material with a substantially open cell structure; or - the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material.

The various embodiments of the methods according to the second and/or third aspect are exceptionally suitable for manufacturing a panel in which the intermediate layer has at least one of the aforementioned properties. In particular, co-extrusion, lamination and/or the formation of a laminated complex allow the intermediate layer, the primary and/or the secondary substrate layer to have a substantially different composition and/or different material properties, forming a panel that shows sufficient stability and adhesion between the various layers.

The intermediate layers as described herein ensure that the panels have better sound insulation. This is particularly important for panels that are used as floor panels. The intermediate layers as described herein additionally and/or alternatively ensure that the panels exhibit improved walking comfort.

In some embodiments, the intermediate layer has a Shore A hardness that is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer. Preferably, the intermediate layer has a Shore A hardness which is 11 units lower than the Shore A hardness of the primary and/or secondary substrate layer, more preferably 12 units lower, even more preferably 13, 14, 15, 16, 17, 18, 19 or 20 units lower. With increasing preference, the various embodiments as described herein further improve the sound damping and/or the walking comfort of the panels.

According to a further or other embodiment, the intermediate layer has an elastic modulus which is at least 10.0% lower than the elastic modulus of the primary and/or secondary substrate layer. The intermediate layer, and in particular the lower elastic modulus relative to the primary and/or secondary substrate layer,

13 BE2021/5830 improves the sound-absorbing properties of the panel and improves walking comfort, in particular when the panel is used as a floor panel. Preferably, the intermediate layer has an elastic modulus that is at least 11.0% lower than the elastic modulus of the primary and/or secondary substrate layer, more preferably 12.0% lower, even more preferably 13.0%, 14.0% or 15.0% lower.

In some embodiments, the intermediate layer comprises a material having a substantially open cell structure. In some embodiments, the intermediate layer comprises a foamed thermoplastic material or a foamed thermoset material. These embodiments provide a panel with improved sound damping and/or improved walking comfort.

According to a further or other embodiment, the intermediate layer has a Shore A hardness that is 10 units lower than the Shore A hardness of the secondary substrate layer and/or the intermediate layer has a modulus of elasticity that is at least 10.0% lower than the modulus of elasticity of the secondary substrate layer. The panel herein has a relatively hard secondary substrate layer and herein provides sufficient rigidity to the panel, the relatively soft intermediate layer providing improved sound damping and/or improved walking comfort to the panel.

According to a further or other embodiment, the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material, wherein the foamed thermoplastic material or the foamed thermosetting material has an empty cell volume comprised between 10.0 and 80.0 vol.%. The empty cell volume within the range described herein is optimal for improving the sound dampening properties of the panel.

According to a further or other embodiment, said foamed thermoplastic material is selected from the group of ethylene vinyl acetate (EVA), irradiation crosslinked polyethylene (IXPE), irradiation crosslinked polypropylene (IXPP), expanded polyethylene (EPE), expanded polyethylene copolymer

14 BE2021/5830 (EPC), polypropylene (PP), polyvinyl chloride (PVC), PVC plastisol, polyurethane (PU), or combinations thereof. These materials are optimally suited as an intermediate layer and provide the panel with improved sound-absorbing properties and/or improved walking comfort. Preferably, said foamed thermoplastic material is selected from the group of ethylene vinyl acetate (EVA), irradiation cross-linked polyethylene (IXPE), expanded polyethylene (EPE), polyvinyl chloride (PVC),

PVC plastisol, polyurethane (PU), or combinations thereof.

According to some embodiments, said primary substrate layer comprises polyvinyl chloride (PVC). Preferably, the polyvinyl chloride has a concentration of at least 95% by weight, more preferably at least 99% by weight, most preferably 100% by weight.

It is possible that the primary substrate layer further comprises one or more fillers selected from the group of inorganic fillers, such as chalk, lime and/or talc, or organic fillers, such as wood, bamboo and/or cork, or mineral fillers. According to further or other embodiments, said primary substrate layer comprises polyvinyl chloride (PVC) and calcium carbonate (CaCO3) as a filler.

In some embodiments, the calcium carbonate (CaCO:3) has a concentration of up to 80% by weight and the polyvinyl chloride (PVC) has a concentration of at least 20% by weight. Preferably, the calcium carbonate (CaCO3) has a concentration comprised between 10 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 90% by weight.

More preferably, the calcium carbonate (CaCO3) has a concentration comprised between 60 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 40% by weight. It has been found that a particularly good stiffness and/or stability is achieved because the proportion of calcium carbonate is greater than the proportion of PVC. Preferably, the calcium carbonate (CaCO3) has a concentration comprised between 65 and 80 wt.% and the polyvinyl chloride (PVC) has a concentration comprised between 20 and wt.%. More preferably, the calcium carbonate (CaCO3) has a concentration

BE2021/5830 comprised between 70 and 80% by weight and the polyvinyl chloride (PVC) a concentration comprised between 20 and 30% by weight. Most preferably, the calcium carbonate (CaCO3) has a concentration of 75% by weight and the polyvinyl chloride (PVC) has a concentration of 25% by weight.

According to some embodiments, said secondary substrate layer comprises polyvinyl chloride (PVC). In some embodiments, the polyvinyl chloride has a concentration of at least 95% by weight, more preferably at least 99% by weight, most preferably 100% by weight.

Preferably, said secondary substrate layer comprises plasticizers in an amount of less than 15 phr, preferably less than 10 phr, more preferably less than 5 phr.

The various embodiments as described herein provide a secondary substrate layer that provides sufficient stability and/or stiffness to the panel.

According to a further or different embodiment, said secondary substrate layer is configured to increase the rigidity of the panel, the secondary substrate layer having at least one of the following properties: - the secondary substrate layer comprises a reinforcement layer; - the secondary substrate layer comprises calcium carbonate (CaCO3) as a filler, or - the secondary substrate layer has a thickness of at least 2.0 mm.

According to some embodiments, said secondary substrate layer comprises a reinforcement layer. A suitable reinforcing layer is, for example, a glass fiber layer. The secondary substrate layer possibly comprises alternative and/or additional reinforcement layers in order to further increase the stiffness.

According to some embodiments, said secondary substrate layer comprises calcium carbonate (CaCO 3 ) as a filler, wherein the calcium carbonate (CaCO 3 ) has a concentration of up to 80% by weight and the polyvinyl chloride (PVC) has a

16 BE2021/5830 has a concentration of at least 20% by weight. Preferably, the calcium carbonate (CaCO2) has a concentration comprised between 10 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 90% by weight.

More preferably, the calcium carbonate (CaCO3) has a concentration comprised between 60 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 40% by weight. It has been found that a particularly good stability and/or stiffness is achieved because the proportion of calcium carbonate is greater than the proportion of PVC. Preferably, the calcium carbonate (CaCO2) has a concentration comprised between 65 and 80% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20 and 35% by weight. More preferably, the calcium carbonate (CaCO3) has a concentration of between 70 and 80% by weight and the polyvinyl chloride (PVC) has a concentration of between 20 and 30% by weight. Most preferably, the calcium carbonate (CaCO3) has a concentration of 75% by weight and the polyvinyl chloride (PVC) has a concentration of 25% by weight.

According to a further or other embodiment, the secondary substrate layer has a thickness of at least 2.0 mm, which imparts an improved stiffness and/or stability to the panel. Preferably, the secondary substrate layer has a thickness of at least 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm or 2.5 mm.

According to a further or other embodiment, said panel is provided with coupling means on at least two opposite edges, whereby a locking is effected on the relevant edges at least in a vertical direction perpendicular to the plane of the panels and/or at least in a horizontal direction in the plane of the panels and perpendicular to the edges. Thanks to the coupling means as described herein, different panels can be coupled to each other in a simple and stable manner.

Preferably, at least one of the aforementioned edges is provided with a groove, this groove being flanked by an upper lip and a lower lip, said intermediate layer extending substantially through the upper lip. More preferably,

17 BE2021/5830, the lower surface of the upper lip is at least partly formed in said primary substrate layer. Even more preferably, said upper lip is mainly formed in the primary substrate layer, the intermediate layer and the secondary substrate layer. The embodiments as described herein have the advantage that the upper lip has excellent rigidity, so that a high-quality and durable coupling is obtained between the coupling means. Furthermore, the presence of the intermediate layer in the upper lip ensures that when connecting and/or disconnecting adjacent floor panels, the upper lip allows a slight compression and/or deformation, making this coupling and/or disconnecting efficient, with the risk of permanent deformation of the upper lip, for example due to fracture, is reduced.

According to some embodiments, in a coupled condition between two adjacent panels, the intermediate layers of said adjacent panels press against each other, forming a seal along the edges of said panels. Such sealing further improves the sound-absorbing properties between adjacent panels.

According to some other embodiments, in a coupled state between two adjacent panels, the intermediate layers of said adjacent panels do not touch each other, forming a space between said intermediate layers along the edges of said panels.

According to some embodiments, the coupling means are configured to couple together the first edge of such panel to the second edge of another such panel, preferably wherein the coupling members include locking members for locking such panel coupled to its first edge at the second edge of another such panel in the direction perpendicular to the plane of the coupled panels and/or in the direction perpendicular to the coupled edges and in the plane of the panels, and wherein a coupling member is located at the first edge in the shape of a tooth and on the second edge there is a coupling part in the form of a groove, the groove being bounded by a lower lip and an upper lip, the

18 BE2021/5830 upper lip is located at the top of the panel, and where at the top of the panel the first edge contains a first closing surface, the distal end of the upper lip containing a second closing surface, the first closing surface and the second closing surface be configured so that when such panel is engaged with its first edge to the second edge of another such panel, the first closing surface of such panel contacts or closely abuts the second closing surface of the other such panel.

The coupling means as described herein are in some embodiments provided on a first and a second opposite edge. In some embodiments, the coupling means are as described herein on a first and a second opposing edge, as well as on a third and a fourth opposing edge.

According to a further or other embodiment, the panel obtained is a floor panel or wall panel.

The methods as described in the second and third independent aspects of the present invention, in its various embodiments, preferably give rise to the manufacture of a panel according to the first independent aspect, in its various embodiments.

With the aim of better demonstrating the features of the invention, a preferred embodiment is described below, by way of example without any limiting character, with reference to the accompanying drawing, in which: Figures 1 and 2 show panels with the features of the invention, comprising first and second edges; figure 3 shows two panels as in figure 2 in coupled condition; figure 4 shows a panel with the features of the invention, comprising a third and a fourth edge;

BE2021/5830 figures 5 and 6 show specific configurations of edges of panels according to the invention; figures 7, 8 and 9 illustrate methods of manufacturing a panel, with the features of the invention in its second aspect; and figure 10 illustrates a method of manufacturing a panel, with the features of the invention in its third aspect.

Figure 1 shows a panel 1 according to the invention, comprising a primary 1 and a secondary substrate layer 2, an intermediate layer 3, and a top layer 4, said intermediate layer 3 being between said primary 1 and secondary substrate layer 2, and wherein said top layer 4 is applied to the secondary substrate layer 2, characterized in that the intermediate layer 3 has at least one of the following properties: the intermediate layer 3 has a Shore A hardness which is 10 units lower than the Shore A hardness of the primary 1 and /or secondary substrate layer 2; the intermediate layer 3 has an elastic modulus which is at least 10.0% lower than the elastic modulus of the primary 1 and/or secondary substrate layer 2; the intermediate layer 3 comprises a material with a substantially open cell structure; or the intermediate layer 3 comprises a foamed thermoplastic material.

The intermediate layer 3 of the panel as shown herein may comprise a foamed thermoplastic material or a foamed thermosetting material, wherein the foamed thermoplastic material or the foamed thermosetting material has an empty cell volume comprised between 10.0 and 80.0 vol.%. Suitable foamed thermoplastic or foamed thermosetting materials may be selected from the group of ethylene vinyl acetate (EVA), irradiation crosslinked polyethylene (IXPE), irradiation crosslinked polypropylene (IXPP), expanded polyethylene (EPE), expanded polyethylene copolymer (EPC), polypropylene (PP) , polyvinyl chloride (PVC), PVC plastisol, polyurethane, or combinations thereof.

20 BE2021/5830

From Figures 1 and 2 it becomes clear that said panel is provided with coupling means on at least two opposite edges, whereby a locking is brought about at the relevant edges at least in a vertical direction perpendicular to the plane of the panels and/or at least in a horizontal direction in the plane of the panels and perpendicular to the edges. Here, at least one of the aforementioned edges is provided with a groove 5, this groove 5 being flanked by an upper lip 6 and a lower lip 7, said intermediate 3 layer extending substantially through the upper lip 6, in particular wherein the lower surface of the upper lip 6 at least partly formed in said primary substrate layer 1, more particularly wherein said upper lip 6 is formed substantially in the primary substrate layer 1, the intermediate layer 3 and the secondary substrate layer 2. As shown, the coupling means herein comprise mutually cooperating coupling parts, namely the groove 5 as described herein, and a tongue-shaped element, tongue or tooth 8. In particular further reference is made to the edges being the first edge 9, comprising the tongue 8, and to the second edge 10, comprising the groove 5, which groove 5 is flanked by the upper lip 6 and the lower lip 7. The lower lip 7 extends further than the upper lip 6. The tongue 8 and the groove 5, when coupled, provide a locking in the direction perpendicular to the plane of the linked panels.

Figures 2 and 3 further show that the top layer 4 comprises a decorative layer 11 and a wear-resistant layer 12. The panel furthermore comprises a damping layer 13 arranged on the underside. The coupling means as shown in Figures 2 and 3 concern the lower lip 6, which comprises an upright locking part 14, which, together with a recess 15 on the underside of the tooth 8, in coupled condition, provides a locking ensures perpendicular to the joined edges and in the plane of the joined panels.

The intermediate layer 3 is located throughout its thickness in the upper lip 6. The minimum thickness D1 of the primary substrate 1 in the upper lip 6 and below the intermediate layer 3 in the section where a panel is coupled with its first edge 9 at the second edge 10 of another such panel the tooth 8 of the first panel contacts the top lip 6 of the second panel is preferably

21 BE2021/5830 at least 0.4 mm, and more preferably at least 0.5 mm and even more preferably at least 1.0 mm.

On the decor side, i.e. the top side, the panel has a first closing surface 16 at the first edge 9. The distal end of the upper lip 6 contains a second closing surface 17. The first closing surface 16 and the second closing surface 17 are configured so that in coupled condition of such panel with its first edge 9 meeting the second edge 10 of another such panel the first closing surface 16 of such panel contacts or closely abuts the second closing surface 17 of the other such panel.

The coupling parts on the first edge 9 and the second edge 10 of the panel of Figure 2 are configured so that the panel can be coupled with its first edge 9 to the second edge 10 of another such panel by means of a turning movement and/or by by means of a sliding movement substantially parallel to the plane of the panels whereby a snapping occurs. The panel shown in Figures 2 and 3 further comprises a chamfer 18 at the first edge 9 and at the second edge 10. Such chamfers are optional within the scope of the invention.

Figure 4 shows an example of the third edge 19 and the opposite fourth edge 20 of a panel according to the invention. This concerns the same panel of which the first edge 9 and the second edge 10 are shown in figure 2 . The same reference numerals therefore have the same meaning herein.

The panel comprises at its third edge 19 a coupling part formed by a downwardly directed upper hook-shaped part. This upper hook-shaped portion contains a lip 21 with a locking element 22 directed downwards forming a male part. The panel comprises at the fourth edge 20 a coupling part formed by an upwardly directed lower hook-shaped part. This lower hook-shaped portion consists of a lip 23 with an upwardly directed locking element 24 defining a female part in the form of a recess 25 proximal thereof. These coupling parts are configured for mutually coupling the third edge 19 of such a panel to the fourth edge 20 of another such panel, whereby when coupling the third edge 19 of

22 BE2021/5830 such a panel on the fourth edge 20 of another such panel the male part engages in the female part whereby a locking in the direction in the plane of the panels and perpendicular to the coupled edges 19, 20 is realized.

The coupling parts on the third edge 19 and on the fourth edge 20 contain a first pair of locking parts 26, 27 which together, in the coupled condition, provide a locking of the coupled panels in the direction perpendicular to the coupled edges. The coupling parts on the third edge 19 and on the fourth edge 20 contain a second pair of locking parts 28, 29 which together, in the coupled condition, provide a locking of the coupled panels in the direction perpendicular to the coupled edges.

The distal end of the tab 21 of the upper hooked portion contains a third closing surface 30. The proximal end of the fourth rim 20 contains a fourth closing surface 31.

The third closing surface 30 and the fourth closing surface 31 are configured so that when such a panel is coupled with its third edge 19 to the fourth edge 20 of another such panel, the third closing surface 30 of such panel contacts or closely abuts the fourth closing face 31 of the other such panel.

Figures 5 and 6 show in detail according to F5A and FSB of Figures 2 and 4, respectively, specific configurations of the edges of panels according to the invention. In the embodiment of Figures 2 and 4, the intermediate layer 3 ends on both opposite edges 9, 10 or 19, 20 in the same vertical plane as the top layer 4.

Figure 5 shows an embodiment in which the intermediate layer 3 contains a protrusion 32 at the edge of the panel. This can be done on both opposing edges, or just one of the pair of opposing edges. This can be achieved via suitable milling operations during the milling of the coupling parts at the relevant edges of the panel. This embodiment has the advantage that in the coupled position between two adjacent panels, the intermediate layers of the adjacent panels press against each other, this forming a seal along the coupled edges of the adjacent panels.

23 BE2021/5830

This can be done on either pair of opposing edges (either on the first pair of opposing edges or on the second pair of opposing edges) or on both pairs of opposing edges.

Figure 6 shows an embodiment in which the edge of the intermediate layer 3 is located in a recess 33 at the edge of the panel. This can be done on both opposing edges, or just one of the pair of opposing edges. This can be achieved via suitable milling operations during the milling of the coupling parts at the relevant edges of the panel. In such embodiments, when interlocked between two adjacent panels, the intermediate plies of the adjacent panels do not touch each other, and a space forms between the intermediary plies at the interlocked edges of the interlocked panels.

This can be done on either pair of opposing edges (either on the first pair of opposing edges or on the second pair of opposing edges) or on both pairs of opposing edges.

It is also possible that on one edge of the panel the intermediate layer has a bulge, and on the opposite edge the edge of the intermediate layer is in a recess on this edge.

Figure 7 illustrates a method of manufacturing a panel according to the second aspect of the present invention. In particular, Figure 7 shows the extrusion of a primary substrate layer 1, the extrusion of an intermediate layer 3 and the lamination of a secondary substrate layer 2. The illustrated method is characterized in that the primary substrate layer 1 and the intermediate layer 3 are formed by co -extrusion. To this end it is shown in Figure 7 that the primary substrate layer 1 is extruded by means of a first extruder 34 and that the intermediate layer 3 is extruded by means of a second extruder 35. The first extruder 34 and the second extruder 35 jointly feed onto a die 36, whereby the primary substrate layer 1 and the intermediate layer are coextruded. In a subsequent

24 BE2021/5830 step the secondary substrate layer 2 is laminated to the co-extruded assembly of the primary substrate layer 1 and the intermediate layer 3. Laminating the secondary substrate layer 2 to the assembly of the primary substrate layer 1 and the intermediate layer 3 as shown in Figure 7, may be performed by means of a roll 39. The secondary substrate layer 2 may be formed offline as a film in order to allow efficient lamination onto the assembly of the primary substrate layer 1 and the intermediate layer 3.

In Figure 8 is illustrated a variant of the method of manufacturing a panel according to the second aspect of the present invention, in which the primary substrate layer 1 and the intermediate layer 3 are co-extruded, albeit by means of two separate dies 36, 37. Immediately after extrusion, the primary substrate layer 1 and the intermediate layer 3 are possibly attached to each other by means of a roller 41.

Figure 9 shows yet another variant of the method according to the second aspect of the present invention, wherein both the primary substrate layer 1, the intermediate layer 3 and the secondary substrate layer 2 are formed by co-extrusion. Here, the primary 1 and the secondary substrate layer 2 are formed by means of the first extruder 34 and the intermediate layer 3 is formed by means of the second extruder 35, which streams of materials are formed by a single die 36 .

Figure 10 shows a method of manufacturing a panel according to the third aspect of the present invention comprising the following steps: extruding a first substrate layer 1, laminating an intermediate layer 3, and laminating a secondary substrate layer 2, where the intermediate layer 3 and the secondary substrate layer 2 are laminated together on the primary substrate layer 1 in the form of a laminated complex 38. According to some embodiments of the method depicted herein, this laminated complex 38 is formed prior to lamination by means of the steps not shown: providing the secondary substrate layer 2, coating

BE2021/5830 said secondary substrate layer 2 with a foamable composition, and foaming said foamable composition to form the intermediate layer 3. The intermediate layer 3 and the secondary substrate layer 2 together form the laminated complex 38 herein. Alternatively, the laminated complex is 38 formed by the steps not shown: providing the secondary substrate layer 2, providing the intermediate layer 3, and bonding the intermediate layer 3 and the secondary substrate layer 2, forming the laminated complex 38. Laminating the laminated complex 38 on the primary substrate layer 1 is possibly performed by means of a roller 42.

Each of these methods further comprises the step of laminating a top layer, which top layer may consist of a decorative and/or wear-resistant layer. This step is not explicitly shown in Figures 7, 8, 9 and 10. Possibly the composite material comprising the primary substrate layer 1, the intermediate layer 3 and the secondary substrate layer 2 is pressed against each other by means of one or more rollers 40.

The methods as shown in each of Figures 7-10 are further characterized in that the intermediate layer 3 has at least one of the following properties: the intermediate layer has a Shore A hardness which is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer; the intermediate layer has an elastic modulus that is at least 10.0% lower than the elastic modulus of the primary and/or secondary substrate layer; the intermediate layer comprises a material with a substantially open cell structure; or the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material.

The intermediate layer of the panel as depicted herein may comprise a foamed thermoplastic material or a foamed thermoset material, wherein the foamed thermoplastic material or foamed thermoset material has a void cell volume comprised between 10.0 and 80.0 vol.%. Suitable foamed thermoplastic or foamed thermosetting materials are possible

26 BE2021/5830 selected from the group of ethylene vinyl acetate (EVA), irradiation crosslinked polyethylene (IXPE), irradiation crosslinked polypropylene (IXPP), expanded polyethylene (EPE), expanded polyethylene copolymer (EPC), polypropylene (PP), polyvinyl chloride (PVC) , PVC plastisol, polyurethane, or combinations thereof.

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

Claims (45)

27 BE2021/5830 Conclusions. 1.- Panel comprising a primary and a secondary substrate layer, an intermediate layer, and a top layer, said intermediate layer being located between said primary and secondary substrate layer, and said top layer being applied to the secondary substrate layer, characterized in that the intermediate layer has at least one of the following properties: the intermediate layer has a Shore A hardness that is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer; the intermediate layer has a modulus of elasticity that is at least 10.0% lower then the elastic modulus of the primary and/or secondary substrate layer; the intermediate layer comprises a material with a substantially open cell structure; or the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material. Panel according to claim 1, characterized in that the intermediate layer has a Shore A hardness that is 10 units lower than the Shore A hardness of the secondary substrate layer and/or that the intermediate layer has an elastic modulus that is at least 10.0% lower. is then the elastic modulus of the secondary substrate layer. Panel according to claim 1 or 2, characterized in that the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material, wherein the foamed thermoplastic material or the foamed thermosetting material has an empty cell volume between 10.0 and 80.0 Vol.% 4 - Panel according to any one of the preceding claims 1-3, characterized in that the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material, wherein the foamed material is selected from the group of ethylene vinyl acetate (EVA), irradiation cross-linked polyethylene (IXPE), irradiation crosslinked polypropylene (IXPP), expanded polyethylene (EPE), expanded 28 BE2021/5830 polyethylene copolymer (EPC), polypropylene (PP), polyvinyl chloride (PVC), PVC plastisol, polyurethane, or combinations thereof. Panel according to any one of the preceding claims 1-4, characterized in that said primary substrate layer comprises polyvinyl chloride (PVC) and calcium carbonate (CaCO3) as filler. Panel according to claim 5, characterized in that the calcium carbonate (CaCO3) has a concentration between 60.0 and 80.0 wt.% and the polyvinyl chloride (PVC) has a concentration between 20.0 and 40.0 wt. .%. 7. Panel according to any one of the preceding claims 1-6, characterized in that said secondary substrate layer comprises polyvinyl chloride (PVC). Panel according to claim 7, characterized in that said secondary substrate layer comprises plasticizers in an amount of less than 15 phr, preferably less than 10 phr, more preferably less than 5 phr. Panel according to any of the preceding claims 1-8, characterized in that said secondary substrate layer is configured to increase the stiffness of the panel, wherein the secondary substrate layer has at least one of the following properties: the secondary substrate layer comprises a reinforcement layer; secondary substrate layer comprises calcium carbonate (CaCO3) as a filler; or the secondary substrate layer has a thickness of at least 2.0 mm. Panel according to claim 9, characterized in that said secondary substrate layer comprises calcium carbonate (CaCO3) as filler, the calcium carbonate (CaCO3) having a concentration between 60.0 and 80.0% by weight and the polyvinyl chloride (PVC) having a concentration comprised between 20.0 and 40.0% by weight. 29 BE2021/5830 11. Panel according to any one of the preceding claims 1-10, characterized in that said panel is provided with coupling means on at least two opposite edges, whereby a locking is effected on the relevant edges at least in a vertical direction perpendicular to the plane of the panels and /or at least in a horizontal direction in the plane of the panels and perpendicular to the edges. 12. Panel according to claim 11, characterized in that at least one of the aforementioned edges is provided with a groove, said groove being flanked by an upper lip and a lower lip, said intermediate layer extending substantially through the upper lip. Panel according to claim 11 or 12, characterized in that the lower surface of the upper lip is at least partly formed in said primary substrate layer. 14. Panel according to any one of the preceding claims 11-13, characterized in that the above-mentioned upper lip is formed substantially in the primary substrate layer, the intermediate layer and the secondary substrate layer. 15. Panel according to any one of the preceding claims 11-14, characterized in that, in a coupled position between two adjacent panels, the intermediate layers of said adjacent panels press against each other, whereby a seal forms along the edges of said panels. 16. Panel according to any one of the preceding claims 11-14, characterized in that, in a coupled condition between two adjacent panels, the intermediate layers of said adjacent panels do not touch each other, a space forming between said intermediate layers along the edges of mentioned panels. 17. Panel according to any one of the preceding claims 1-16, characterized in that said panel is a floor panel or wall panel. 30 BE2021/5830 18.- Method for manufacturing a panel, comprising the steps of: extruding a primary substrate layer, extruding an intermediate layer, extruding and/or laminating a secondary substrate layer, and laminating a top layer, characterized in that at least the primary substrate layer and the intermediate layer are formed by co-extrusion. 19. Method according to claim 18, characterized in that the primary substrate layer, the intermediate layer and the secondary substrate layer are formed by means of co-extrusion. 20. Method according to claim 18, characterized in that the secondary substrate layer is laminated. 21. Method according to any one of the preceding claims 18-20, characterized in that said layers, which are formed by means of co-extrusion, are formed by a single mould. 22. Method according to any one of the preceding claims 18-20, characterized in that said layers, which are formed by means of co-extrusion, are formed by two or more separate moulds. 23.- Method for manufacturing a panel, comprising the steps of: extruding a first substrate layer, laminating an intermediate layer, laminating a secondary substrate layer, and laminating a top layer, characterized in that at least the intermediate layer and the secondary substrate layer are laminated together to the primary substrate layer in the form of a laminated complex. BE2021/5830 24 - Method according to claim 23, characterized in that said laminated complex is formed by the steps of: providing the secondary substrate layer, coating said secondary substrate layer with a foamable composition, and foaming said foamable composition with formation of the intermediate layer. 25. Method according to claim 24, characterized in that said foamable composition is foamed by heating with formation of the intermediate layer. 26. Method according to claim 23, characterized in that said laminated complex is formed by the steps of: providing the secondary substrate layer, providing the intermediate layer, and bonding the intermediate layer and the secondary substrate layer. 27. Method according to claim 26, characterized in that the secondary substrate layer and/or the intermediate layer are subjected to a corona treatment prior to bonding. 28. Method according to any of claims 18-27, characterized in that the intermediate layer has at least one of the following properties: the intermediate layer has a Shore A hardness which is 10 units lower than the Shore A hardness of the primary and/or secondary substrate layer; the intermediate layer has an elastic modulus that is at least 10.0% lower than the elastic modulus of the primary and/or secondary substrate layer; the intermediate layer comprises a material with a substantially open cell structure; or the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material. 32 BE2021/5830 29. Method according to any one of the preceding claims 18-28, characterized in that the intermediate layer has a Shore A hardness that is 10 units lower than the Shore A hardness of the secondary substrate layer and/or that the intermediate layer has an elastic modulus that is at least 10.0% lower than the elastic modulus of the secondary substrate layer. 30. Method according to any one of the preceding claims 18-29, characterized in that the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material, wherein the foamed thermoplastic material or the foamed thermosetting material has an empty cell volume between 10.0 and 80.0 vol.% 31. Method according to any one of the preceding claims 18-30, characterized in that the intermediate layer comprises a foamed thermoplastic material or a foamed thermosetting material, wherein the foamed material is selected from the group of ethylene vinyl acetate (EVA), irradiation cross-linked polyethylene (IXPE ), irradiation crosslinked polypropylene (IXPP), expanded polyethylene (EPE), expanded polyethylene copolymer (EPC), polypropylene (PP), polyvinyl chloride (PVC), PVC plastisol, polyurethane, or combinations thereof. 32. Method according to any one of the preceding claims 18-31, characterized in that said primary substrate layer comprises polyvinyl chloride (PVC) and calcium carbonate (CaCO3) as filler. 33. Method according to claim 32, characterized in that the calcium carbonate (CaCO3) has a concentration between 60.0 and 80.0% by weight and the polyvinyl chloride (PVC) has a concentration between 20.0 and 40.0% by weight. %. 34. Method according to any one of the preceding claims 18-32, characterized in that said secondary substrate layer comprises polyvinyl chloride (PVC). 33 BE2021/5830 Method according to claim 34, characterized in that said secondary substrate layer comprises plasticizers in an amount of less than 15 phr, preferably less than 10 phr, more preferably less than 5 phr. 36. Method according to any of the preceding claims 18-35, characterized in that said secondary substrate layer 1s is configured to increase the rigidity of the panel, the secondary substrate layer having at least one of the following properties: the secondary substrate layer comprises a reinforcement layer; secondary substrate layer comprises calcium carbonate (CaCO3) as a filler; or the secondary substrate layer has a thickness of at least 2.0 mm. 37. Method according to claim 36, characterized in that said secondary substrate layer comprises calcium carbonate (CaCO3) as a filler, wherein the calcium carbonate (CaCO3) has a concentration comprised between 60.0 and 80.0% by weight and the polyvinyl chloride (PVC) has a concentration comprised between 20.0 and 40.0% by weight. 38. Method according to any one of the preceding claims 18-37, characterized in that the panel obtained is provided with coupling means on at least two opposite edges, wherein a locking is effected on the relevant edges at least in a vertical direction perpendicular to the plane of the panels. and/or at least in a horizontal direction in the plane of the panels and perpendicular to the edges. 39. Method according to claim 38, characterized in that at least one of the aforementioned edges is provided with a groove, said groove being flanked by an upper lip and a lower lip, said intermediate layer extending substantially through the upper lip. Method according to claim 38 or 39, characterized in that the lower surface of the upper lip is at least partly formed in said primary substrate layer. 34 BE2021/5830 41. Method as claimed in any of the foregoing claims 38-40, characterized in that the above-mentioned upper lip is formed substantially in the primary substrate layer, the intermediate layer and the secondary substrate layer. 42. Method according to any one of the preceding claims 38-41, characterized in that, in a coupled condition between two adjacent panels obtained, the intermediate layers of said adjacent panels press against each other, a seal forming along the edges of said adjacent panels. panels. 43. Method according to any one of the preceding claims 38-41, characterized in that, in a coupled condition between two adjacent panels obtained, the intermediate layers of said adjacent panels do not touch each other, a space forming between said intermediate layers along the edges of said obtained panels. Panel according to any one of the preceding claims 18-43, characterized in that said panel obtained is a floor panel or wall panel. 45. Method according to any one of the preceding claims 18-44, wherein a floor panel is obtained according to any one of the claims 1-17.