PANEL FOR COVERING A SURFACE

Description

[0001] The invention relates to a panel for cladding a surface, in particular a floor panel for cladding a floor area of ​​a building room, comprising a panel core enclosed by a flat panel surface, a flat panel underside spaced apart from and parallel to the panel underside, and four panel side surfaces each connecting the panel surface to the panel underside, wherein mutually complementary coupling elements in the form of an upper coupling element and a lower coupling element are arranged on two opposing panel side surfaces, the coupling elements being designed in such a way as to enable a coupling of a first such panel with a second such panel by means of a relative movement of the upper coupling element of the first panel towards the lower coupling element of the second panel.The upper coupling element has a wedge-shaped projection at its distal end, and the lower coupling element has a counter surface which, in the coupled state of two panels, rests against the wedge-shaped projection, so that the wedge-shaped projection together with the counter surface forms a first coupling section of the coupling elements; the upper coupling element has a locking element adjoining the wedge-shaped projection, and the lower coupling element has a locking receptacle adjoining the counter surface, into which, in the coupled state of two panels, the locking element is engaged, so that the locking element together with the locking receptacle forms a second coupling section of the coupling elements; the upper coupling element has a locking receptacle adjoining the locking element, and the lower coupling element has a locking element adjoining the locking receptacle at its distal end.which, in the coupled state of two panels, engages in the locking receptacle, so that the locking receptacle together with the locking element forms a third coupling section of the coupling elements. Such a panel is known from US 10,000,935 B2.

[0002] Such a panel always has a lower coupling element and an upper coupling element. The terms "lower" and "upper" refer to the fact that, during panel assembly, an upper coupling element of a panel to be installed is pressed onto a lower coupling element of a panel that is already installed and lying on the substrate. To form the first coupling section, the wedge-shaped projection of the upper coupling element is pressed onto a counter surface of the lower coupling element that slopes towards the substrate. To form the second coupling section, the lower coupling element is spread open in the area of ​​the locking receptacle by the penetrating locking element of the upper coupling element. To form the third coupling section, the upper coupling element is spread open in the area of ​​the locking receptacle by the penetrating locking element of the lower coupling element.

[0003] The relatively large contact area between the upper and lower coupling elements already results in a high fluid resistance for a composite of such panels. "Fluid resistance" refers to the ability of a panel composite to resist the passage of fluids, such as water, from the top of the panels and between adjacent panels to the underside, ideally preventing this passage entirely. However, experience has shown that even with this, complete fluid resistance of such a panel composite cannot be achieved in all situations.

[0004] FR 2 922 568 A1 discloses that in cross-section the tongue of a first panel on its underside and the lower lip of the groove of an adjacent second panel, which is identical to the first, each have two downward-projecting protrusions on their upper side and two recesses that are complementary to each other and interlock when one panel is rotated relative to another to form a double means for engaging the tongue in the groove.

[0005] DE 10 2006 057 491 A1 discloses a panel with a usable surface and four edges, opposite pairs of edges having corresponding retaining profiles so that identical panels can be joined at all four edges, wherein the retaining profiles of a first pair of edges can be joined by angling, and wherein the retaining profiles of a second pair of edges are designed as complementary hook elements, so that an identical neighboring panel can be joined at each of the hook elements essentially by means of a joining movement that takes place in a plane of movement perpendicular to the plane of the panel, with the proviso that at least one of the hook elements of the second pair of edges has a separate vertical locking element which projects at least partially into the joining path of the hook elements, wherein the vertical locking element can be automatically moved out of the joining path during the joining movement of the hook elements of two panels in order to release it.and, in the locked state of the hook elements, can be automatically moved back into the joining path by spring action.

[0006] DE 20 2019 101 807 U1 discloses a panel with a panel core, a panel top, a panel bottom, and at least one pair of opposing complementary panel edges, which are provided with complementary locking means, wherein the complementary locking means are designed such that, in the joined state of two such panels below a visible joint, a locking effect of the panel edges can be achieved by means of the joined complementary locking means both in a direction perpendicular to the panel top and a locking effect against the panels moving apart within the panel plane away from each other in a direction perpendicular to the locked panel edges, with the proviso that the panel edges provided with the complementary locking means have an upper sub-region and a lower sub-region with respect to the thickness of the panel.wherein the complementary locking means are arranged and designed in the lower part of the panel edges, wherein the upper part of the panel edges is provided for the design of the upper joint area including the visible part of the joint and for this purpose the upper part has an edge chamfer on each panel edge of the edge pair which forms a recessed joint when two of these panels are joined, wherein in the upper part of the panel edges the edge chamfers of the complementary panel edges are of different sizes, and that when two complementary panel edges are joined the larger edge chamfer is covered by the smaller edge chamfer.

[0007] Based on this, the object of the invention is to provide a panel for cladding a surface that has a particularly high fluid resistance.

[0008] This problem is solved by the subject matter of claim 1. Preferred embodiments of the invention are described in the dependent claims.

[0009] According to the invention, a panel for cladding a surface, in particular a floor panel for cladding a floor area of ​​a building room, is provided with a panel core enclosed by a flat panel surface, a flat panel underside spaced apart from and parallel to the panel underside, and four panel side surfaces each connecting the panel surface to the panel underside, wherein mutually complementary coupling elements in the form of an upper coupling element and a lower coupling element are arranged on two opposing panel side surfaces, which are designed in such a way that they enable a coupling of a first such panel with a second such panel by means of a relative movement of the upper coupling element of the first panel towards the lower coupling element of the second panel.The upper coupling element has a wedge-shaped projection at its distal end, and the lower coupling element has a counter surface which, in the coupled state of two panels, rests against the wedge-shaped projection, so that the wedge-shaped projection together with the counter surface forms a first coupling section of the coupling elements; the upper coupling element has a locking element adjoining the wedge-shaped projection, and the lower coupling element has a locking receptacle adjoining the counter surface, into which, in the coupled state of two panels, the locking element is engaged, so that the locking element together with the locking receptacle forms a second coupling section of the coupling elements; the upper coupling element has a locking receptacle adjoining the locking element, and the lower coupling element has a locking element adjoining the locking receptacle at its distal end.which, in the coupled state of two panels, engages in the locking receptacle, such that the locking receptacle together with the locking element forms a third coupling section of the coupling elements, characterized in that the surfaces of the locking receptacle and the locking element facing each other in the coupled state of two panels have complementary wave structures, wherein the surfaces of the locking element are convex overall perpendicular to the panel side surfaces having the complementary coupling elements, and the surface of the locking receptacle is concave overall perpendicular to the panel side surfaces having the complementary coupling elements.

[0010] A key aspect of the invention is that the surface of the locking receptacle and the surface of the locking element each have a wave structure, with these wave structures being complementary to each other. The complementary nature of the wave structures means that the shape of these wave-like surfaces is such that, when the two panels are coupled, they lie flat against each other. This is achieved by the surface shapes of the locking receptacle and the locking element corresponding to each other. Thus, where the locking receptacle has a wave trough, the locking element has a wave crest, and vice versa. In this way, an interlocking of the two surfaces is effectively achieved.This results in a larger interface between the locking receptacle and the locking element compared to flat surfaces, which ultimately further hinders fluid penetration between the locking receptacle and the locking element. In this way, an even higher fluid resistance can be achieved in a panel assembly consisting of such panels.

[0011] In principle, a wide variety of wave structures can be used to achieve the fluid resistance in question. However, according to a preferred embodiment of the invention, the wave structures in the locking receptacle and the locking element are arranged perpendicular to the panel side surfaces, which have the complementary coupling elements. It has been shown that particularly good fluid resistance can be achieved in this way. Furthermore, the shape of the wave structures can follow various forms. However, according to a preferred embodiment of the invention, the wave structures in the locking receptacle and the locking element are arranged sinusoidally.

[0012] The number of wave crests and troughs can, in principle, vary. However, according to a preferred embodiment of the invention, the wave structures are provided to have at least four wave crests, preferably at least five, and most preferably at least six. It has been shown that even such a small number of wave crests leads to a significant improvement in fluid strength. Furthermore, it is preferred that the height difference between the wave crests and troughs is between a maximum of 7% and a minimum of 1% of the total thickness of the panel, which is determined by the distance between the panel surface and the panel underside.

[0013] The invention allows the surfaces of the locking element and the surface of the locking receptacle to be essentially flat overall, i.e., without considering the wave structure. This means that the wave structures practically oscillate around a flat plane. According to the invention, however, the surface of the locking element is convex overall perpendicular to the panel side surfaces that have the complementary coupling elements, and the surface of the locking receptacle is concave overall perpendicular to the panel side surfaces that have the complementary coupling elements. When it is stated here that surfaces are convex or concave overall, this refers to the shape of the surfaces without the wave structures. The wave structures, of course, cause both surfaces to exhibit local convex or concave areas.Overall, however, the surface of the locking element is curved outwards according to the preferred embodiment of the invention described here, i.e. towards the surface of the locking receptacle in the locked state of two panels, while the surface of the locking receptacle is accordingly retracted so that it is adapted to the surface of the locking element.

[0014] According to a preferred embodiment of the invention, the surfaces of the locking element and the surface of the locking receptacle are arranged in a segment-shaped pattern perpendicular to the panel side surfaces, which have the complementary coupling elements, with the exception of the wave structures. The radius of the surface of the locking element and the surface of the locking receptacle lie in the range of 85% to 95% of the total thickness of the panel, which is determined by the distance between the panel surface and the panel underside. It has been found that an advantageous and uniform force distribution occurs within these values. The resulting flat arc shape provides the coupling elements with beneficial protection against static friction and thus against the risk of breakage.

[0015] According to a preferred embodiment of the invention, a tangent to the center of the circular segment shape of the surface of the locking element and / or a tangent to the center of the circular segment shape of the surface of the locking receptacle, relative to the panel surface and the panel underside, respectively, encloses an arc angle α of a maximum of 45°, preferably a maximum of 35°, and particularly preferably a maximum of 25°. In this way, high vertical forces can be absorbed horizontally and uniformly by the locking element of the lower coupling element. Simultaneously, a sufficient inclination is provided to form the third coupling segment. This protects the components and secures the panel.

[0016] According to a preferred embodiment of the invention, the locking element has a locking projection and the locking receptacle has a locking abutment, which interact with each other when two panels are coupled. Such a design allows for a reliable, positive-locking second coupling section, whereby the interaction of the locking projection and locking abutment prevents the panel from being subjected to any component-damaging stress.

[0017] According to a preferred embodiment of the invention, the locking element has a locking projection and the locking receptacle has a locking abutment, which interact with each other when two panels are coupled. Such a design allows for a reliable, positive-locking third coupling section, whereby the interaction of the locking projection and the locking abutment prevents the panel from being subjected to any component-damaging stress.

[0018] According to a preferred embodiment of the invention, the material thickness of the lower coupling element between the panel underside and the locking receptacle is less than the material thickness of the upper coupling element between the panel surface and the locking receptacle. This design results in the coupling elements being spread apart under less stress when two panels are joined, compared to previously known panels, and thus reducing the risk of material failure or breakage.

[0019] It has been found that the installation loads on the lower coupling element can generally be better balanced than those on the upper coupling element. This is partly due to the fact that the lower coupling element rests on the surface being clad during the installation of the upper coupling element. The forces acting on the lower coupling element can thus be directly and evenly absorbed by the substrate and are therefore less damaging to individual components of the lower coupling element. In contrast, forces acting on the upper coupling element during the joining of two panels do not have this opportunity for force distribution, so the upper coupling element is generally more prone to material failure. Such material failure, or fracture, typically occurs in areas of high stress and minimal material thickness.The lower coupling element has the smallest material thickness between the panel underside and the locking receptacle. The upper coupling element has the smallest material thickness between the panel surface and the locking receptacle. In the following, "material thickness" refers to a minimum or maximum material thickness in this respective area. Whenever the term "material thickness" is used, it refers to this definition or arrangement.

[0020] In light of the aforementioned aspects, a preferred embodiment of the invention provides that the material thickness of the lower coupling element between the panel underside and the locking receptacle is at least 62%, preferably at least 67%, and particularly preferably at least 72% of the material thickness of the upper coupling element between the panel surface and the locking receptacle. Furthermore, it is preferred that the material thickness of the lower coupling element between the panel underside and the locking receptacle is at most 82%, at most 77%, and particularly preferably at most 72% of the material thickness of the upper coupling element between the panel surface and the locking receptacle.Preferably, the material thickness of the upper coupling element between the panel surface and the locking receptacle is at least 34%, preferably at least 39%, and particularly preferably at least 44% of the total thickness of the panel given by the distance of the panel surface from the panel underside.

[0021] It is further preferred that the material thickness of the upper coupling element between the panel surface and the locking receptacle is a maximum of 54%, preferably a maximum of 49%, and particularly preferably a maximum of 44% of the total panel thickness determined by the distance between the panel surface and the panel underside. Preferably, the material thickness of the lower coupling element between the panel underside and the locking receptacle is at least 24%, preferably at least 29%, and particularly preferably at least 34% of the total panel thickness determined by the distance between the panel surface and the panel underside. Furthermore, it is preferred that the material thickness of the lower coupling element between the panel underside and the locking receptacle is a maximum of 44%, preferably a maximum of 39%, and particularly preferably a maximum of 34% of the total panel thickness determined by the distance between the panel surface and the panel underside.

[0022] Finally, according to a preferred embodiment of the invention, the panel consists of at least one carrier or core onto which different functional layers are applied or attached, such as decorative layers, wear-resistant layers, and / or counter-tension layers. The coupling elements described according to the invention are essentially formed within the carrier or core. The carrier or core of a panel according to the invention can, for example, be based on a natural material, a plastic, a wood-plastic composite (WPC), or a mineral-plastic composite (MPC, SPC). Layered structures made of several of the aforementioned materials can also be used, for example, gypsum board or wood-plastic composite panels.

[0023] For example, the substrate can be made of a thermoplastic, elastomeric, or thermosetting plastic. According to the invention, substrates made of minerals such as natural and artificial stone slabs, concrete slabs, gypsum fiberboards, so-called WPC boards (made from a mixture of plastic and wood), so-called MPC or SPC boards (made from a mixture of plastic and mineral or stone flour), as well as boards made from natural raw materials such as cork and wood, can also be used as substrates. Boards made from biomass as natural materials, such as straw, corn straw, bamboo, leaves, algae extracts, hemp, and oil palm fibers, can also be used according to the invention. Furthermore, recycled materials from the aforementioned materials can be used within the framework of the inventive process. Finally, the boards can be based on the natural material cellulose, such as paper or cardboard.

[0024] Wood-based materials within the meaning of the invention include not only solid wood materials but also materials such as cross-laminated timber (CLT), glulam (glued laminated timber), blockboard, veneer plywood, laminated veneer lumber (LVL), veneer strips, and flexible plywood. Furthermore, wood-based materials within the meaning of the invention also include particleboard such as particleboard, extruded particleboard, oriented strand board (OSB), and particleboard strips, as well as wood fiber materials such as wood fiber insulation boards (HFD), medium-density fiberboard (MB), and high-density fiberboard (HFH), and in particular medium-density fiberboard (MDF) and high-density fiberboard (HDF).Modern wood-based materials such as wood-polymer composites (WPC), sandwich panels made of a lightweight core material such as foam, rigid foam, or paper honeycomb and a wood layer applied to it, as well as mineral-bonded particleboard, for example with cement, are also wood-based materials within the meaning of the invention. Cork also constitutes a wood-based material within the meaning of the invention.

[0025] For the purposes of the invention, the term "fibrous materials" refers to materials such as paper and nonwovens based on plant, animal, mineral, or synthetic fibers, as well as cardboard. Examples of fiber materials made from plant fibers include papers and nonwovens made from cellulose fibers, as well as boards made from biomass such as straw, corn straw, bamboo, leaves, algae extracts, hemp, cotton, or oil palm fibers. Examples of animal fiber materials include keratin-based materials such as wool or horsehair. Examples of mineral fiber materials include mineral wool or glass wool.

[0026] Furthermore, the substrate can be a plastic-based substrate, meaning it may contain or consist of a plastic. Examples of thermoplastic polymers include polyvinyl chloride, polyolefins (e.g., polyethylene (PE), polypropylene (PP), polyamides (PA), polyurethanes (PU), polystyrene (PS), acrylonitrile butadiene styrene (ABS), polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polyetheretherketone (PEEK), or mixtures or copolymers thereof. The polymers may contain common fillers, such as talc, calcium carbonate (chalk), aluminum oxide, silica gel, quartz flour, wood flour, or gypsum. They may also be colored in known ways. In particular, the substrate material may be designed to contain a flame retardant and / or an antistatic additive.

[0027] Thermoplastic materials, in particular, offer the advantage that the products made from them can be recycled very easily. Recycled materials from other sources can also be used. This provides a further opportunity to reduce manufacturing costs.

[0028] The carrier material, or the material from which the carrier is formed, can be, for example, a matrix material and a solid material, wherein the matrix material is present in an amount, based on the carrier material, of ≥ 25 wt.% to ≤ 55 wt.%, in particular of ≥ 35 wt.% to ≤ 45 wt.%, and wherein the solid material is present in an amount, based on the carrier material, of ≥ 45 wt.% to ≤ 75 wt.%, in particular of ≥ 55 wt.% to ≤ 65 wt.%, and wherein the matrix material and the solid material together are present, based on the carrier material, in an amount of ≥ 95 wt.%, in particular of ≥ 99 wt.%, and the solid material is formed to at least 50 wt.%, in particular of at least 80 wt.%, in particular of at least 95 wt.%, based on the solid material, from a solid composition consisting of at least one first layered silicate powder. and a second layered silicate powder, and the matrix material to at least 50 wt.-%, in particular at least 80 wt.%, in particular at least 95 wt.%, based on the matrix material, is formed by a plastic composition consisting of a homopolymer and at least a first copolymer and a second copolymer.

[0029] Layered silicate powder, as is generally understood, is a powder made from a layered silicate. Layered silicates are minerals from the silicate group whose silicate anions are typically arranged in layers. For example, layered silicates include minerals from the mica group, the chlorite group, the kaolinite group, and the serpentine group.

[0030] Thus, the solid material can advantageously consist at least largely of the mineral layered silicate, which can be used, for example, in powder form or present in the carrier material in the form of particles. In principle, the solid material can consist of a powdered solid.

[0031] Layered silicates offer the advantage that they allow the production of a carrier with good mechanical properties and, at the same time, can be easily processed into suitable powders due to their layered structure.

[0032] The invention will now be explained in more detail using a preferred embodiment and with reference to the drawings.

[0033] The drawings show Fig. 1 schematically a sectional view of the coupling elements of two panels according to a preferred embodiment of the invention in an uncoupled state and Fig. 2 schematically a sectional view of the coupling elements of the in Fig. 1 Panels shown in coupled state.

[0034] Out of Fig. 1 Two panels 10a, 10b are shown in a schematic sectional view, which are intended for cladding a surface. Specifically, the preferred embodiment of the invention shown here comprises two floor panels for cladding a floor area of ​​a building room. Fig. 1 The image shows panels 10a and 10b in an uncoupled state, i.e., separated from each other. The panels 10a and 10b shown here have thermoplastic polymers as their base material. Alternatively, they can have HDF or MDF cores.

[0035] The two panels 10a, 10b each have a panel core enclosed by a flat panel surface 12, a flat panel underside 14 spaced apart from and parallel to the panel underside 14, and four panel side surfaces connecting the panel surface 12 to the panel underside 14. As shown in Fig. 1 As can be seen, on two opposing panel side surfaces, complementary coupling elements 16, 18 in the form of an upper coupling element 16 and a lower coupling element 18 are arranged, which are designed in such a way that they enable a coupling of a first such panel 10a with a second such panel 10b by means of a relative movement of the upper coupling element 16 of the first panel 10a to the lower coupling element 18 of the second panel 10b.

[0036] The panels 10a, 10b now each have three coupling sections on their coupling elements 16, 18, as follows: The upper coupling element 16 has a wedge-shaped projection 20 at its distal end, and the lower coupling element 18 has a counter surface 22 which, in the coupled state of two panels 10a, 10b, rests against the wedge-shaped projection 20, so that the wedge-shaped projection 20 together with the counter surface 22 forms the first coupling section of the coupling elements 16, 18.

[0037] Furthermore, the upper coupling element 16 has a locking element 24 adjoining the wedge-shaped projection 20, and the lower coupling element 18 has a locking receptacle 26 adjoining the opposite surface 22, into which the locking element 24 is engaged when two panels 10a, 10b are coupled, so that the locking element 24 together with the locking receptacle 26 forms the second coupling section of the coupling elements 16, 18.

[0038] Finally, it should be noted that the upper coupling element 16 has a locking receptacle 28 adjoining the locking element 24, and the lower coupling element 18 has a locking element 30 adjoining the locking receptacle 26 at its distal end, which engages in the locking receptacle 28 when two panels 10a, 10b are coupled, so that the locking receptacle 28 together with the locking element 30 forms the third coupling section of the coupling elements 16, 18.

[0039] Furthermore, how from Fig. 1 As can be seen, for both panels 10a and 10b, the locking element 24 has a locking projection 42 and the locking receptacle 26 has a locking abutment 44. Fig. 2 It can be seen that the locking projection 42 and the locking abutment 44 interact with each other in the coupled state of two panels 10a, 10b to ensure a firm connection between the panels 10a, 10b. Furthermore, the locking element 30 has a locking projection 46 and the locking receptacle 28 has a locking abutment 48, which, as can also be seen from Fig. 2 It can be seen that in the coupled state of two panels 10a, 10b, they interact with each other.

[0040] It is essential that the surfaces 32, 34 of the locking receptacle 28 and the locking element 30, respectively, which face each other in the coupled state of two panels 10a, 10b, exhibit complementary wave structures. Fig. 1 It can be seen that the wave structures in the locking receptacle 28 and the locking element 30 run perpendicular to the panel side surfaces having the mutually complementary coupling elements 16, 18 and that the wave structures in the locking receptacle 28 and the locking element 30 run sinusoidally.

[0041] Furthermore, the Fig. 1 and 2 It can be seen that the surface 32 of the locking element 30 is convex in a direction perpendicular to the panel side surfaces having the mutually complementary coupling elements 16, 18, and that the surface 34 of the locking receptacle 28 is concave in a direction perpendicular to the panel side surfaces having the mutually complementary coupling elements 16, 18.

[0042] Furthermore, the figures show that the surface 32 of the locking element 30 and the surface 34 of the locking receptacle 28 are perpendicular to the panel side surfaces, which have the complementary coupling elements 16, 18, and, apart from the wave structures, are segments of a circle. The radius R of surface 32 of the locking element 30 and surface 34 of the locking receptacle 28 lies in the range of 85% to 95% of the total thickness G of the panel 10a, 10b, which is determined by the distance of the panel surface 12 from the panel underside 14.

[0043] Furthermore, it should be mentioned that for panels 10a and 10b, a tangent to the center of the circular segment shape of surface 32 of the locking element 30 and a tangent to the center of the circular segment shape of surface 34 of the locking receptacle 28, relative to the panel surface 12 and the panel underside 14, respectively, form an arc angle α of a maximum of 45°. In this way, high vertical forces can be absorbed horizontally and uniformly by the locking element of the lower coupling element 18.

[0044] Furthermore, the material thickness UM of the lower coupling element 18 between the panel underside 14 and the locking receptacle 26 is less than the material thickness OM of the upper coupling element 16 between the panel surface 12 and the locking receptacle 28, which leads to the advantages mentioned in detail above with regard to breakage resistance. Reference symbol list

[0045] 10a, 10b Panels 12 Panel surface 14 Panel underside 16 Upper coupling element 18 Lower coupling element 20 Wedge-shaped projection 22 Counter surface 24 Detent element 26 Detent receptacle 28 Locking receptacle 30 Locking element 32 Surface of the locking element 34 Surface of the locking receptacle 42 Detent projection 44 Detent abutment 46 Locking projection 48 Locking abutment G Total thickness OM Material thickness of the upper coupling element UM Material thickness of the lower coupling element α Arc angle R Radius

Claims

1. Panel (10a, 10b) for cladding a surface with a panel core that is enclosed by a flat panel surface (12), a flat panel lower surface (14), which is spaced therefrom and parallel thereto, and four panel side surfaces each connecting the panel surface (12) to the panel lower surface (14), wherein complementary coupling elements (16, 18) are arranged on two opposing side surfaces of the panel in the form of an upper coupling element (16) and a lower coupling element (18), which are configured in such a way that they enable a first such panel (10a) to be coupled to a second such panel (10b) by means of a relative movement of the upper coupling element (16) of the first panel (10a) towards the lower coupling element (18) of the second panel (10b), the upper coupling element (16) has a wedge-shaped projection (20) at its distal end and the lower coupling element (18) has a mating surface (22) which, in the coupled state of two panels (10a, 10b), bears against the wedge-shaped projection (20), so that the wedge-shaped projection (20) together with the mating surface (22) form a first coupling section of the coupling elements (16, 18), the upper coupling element (16) has a latching element (24) adjoining the wedge-shaped projection (20) and the lower coupling element (18) has a latching receptacle (26) adjoining the mating surface (22), into which the latching element (24) is latched in the coupled state of two panels (10a, 10b), so that the latching element (24) together with the latching receptacle (26) form a second coupling section of the coupling elements (16, 18), the upper coupling element (16) has a locking receptacle (28) adjoining the latching element (24) and the lower coupling element (18) has at its distal end a locking element (30) adjoining the latching receptacle (26), which locking element engages in the locking receptacle (28) in the coupled state of two panels (10a, 10b), so that the locking receptacle (28) together with the locking element (30) form a third coupling section of the coupling elements (16, 18), wherein the surfaces (32, 34) of the locking receptacle (28) or the locking element (30) facing each other in the coupled state of two panels (10a, 10b) have mutually complementary wave structures, characterised in that the surfaces (32) of the locking element (30) extend generally convexly perpendicularly to the panel side surfaces having the mutually complementary coupling elements (16, 18) and the surface (34) of the locking receptacle (28) extends generally concavely perpendicularly to the panel side surfaces having the mutually complementary coupling elements (16, 18).

2. Panel (10a, 10b) according to Claim 1, characterised in that the wave structures in the locking receptacle (28) and the locking element (30) extend perpendicular to the panel side surfaces having the mutually complementary coupling elements.

3. Panel (10a, 10b) according to Claim 1 or 2, characterised in that the wave structures in the locking receptacle (28) and the locking element (30) are sinusoidal.

4. Panel (10a, 10b) according to one of the preceding claims, characterised in that the wave structures have at least four wave crests.

5. Panel (10a, 10b) according to one of the preceding claims, characterised in that the difference in height between the wave crests and the wave troughs is between a maximum of 7% and a minimum of 1% of the total thickness (G) of the panel (10a, 10b) given by the distance of the panel surface (12) from the panel undersurface (14).

6. Panel (10a, 10b) according to one of the preceding claims, characterised in that the surfaces (32) of the locking element (30) and the surface (34) of the locking receptacle (28) are perpendicular to the panel side surfaces having the mutually complementary coupling elements (16, 18), apart from the wave structures, the radius (R) of the surface (32) of the locking element (30) and the surface (34) of the locking receptacle (28) being in the range from 85% to 95% of the total thickness (G) of the panel (10a, 10b) given by the distance of the panel surface (12) from the panel lower surface (14).

7. Panel (10a, 10b) according to one of the preceding claims, characterised in that a tangent to the centre of the circular section shape surfaces (32) of the locking element (30) and / or a tangent to the centre of the circular section shape of the surface (34) of the locking receptacle (28) with respect to the panel surface (12) and the panel undersurface (14) includes a respective arc angle (α) of at most 45°.

8. Panel (10a, 10b) according to one of the preceding claims, characterised in that the latching element (24) has a latching projection (42) and the latching receptacle (26) has a latching abutment (44), which interact with one another in the coupled state of two panels (10a, 10b).

9. Panel (10a, 10b) according to one of the preceding claims, characterised in that the locking element (30) has a locking projection (46) and the locking receptacle (28) has a locking abutment (48), which interact with one another in the coupled state of two panels (10a, 10b).

10. Panel (10a, 10b) according to one of the preceding claims, characterised in that the material thickness (UM) of the lower coupling element (18) between the lower panel surface (14) and the latching receptacle (26) is less than the material thickness (OM) of the upper coupling element (16) between the panel surface (12) and the locking receptacle (28).

11. Panel (10a, 10b) according to one of the preceding claims, characterised in that the material thickness (UM) of the lower coupling element (18) between the lower panel surface (14) and the latching receptacle (26) is at least 62% of the material thickness (OM) of the upper coupling element (16) between the panel surface (12) and the locking receptacle (28).

12. Panel (10a, 10b) according to one of the preceding claims, characterised in that the material thickness (UM) of the lower coupling element (18) between the lower panel surface (14) and the latching receptacle (26) is at most 82% of the material thickness (OM) of the upper coupling element (16) between the panel surface (12) and the locking receptacle (28).

13. Panel (10a, 10b) according to one of the preceding claims, characterised in that the material thickness (OM) of the upper coupling element (16) between the panel surface (12) and the locking receptacle (28) is at least 34% of the total thickness (G) of the panel (10a, 10b) given by the distance of the panel surface (12) from the panel lower surface (14).

14. Panel (10a, 10b) according to one of the preceding claims, characterised in that the panel (10a, 10b) comprises at least partially thermoplastic styrene block copolymers as its base material.