Heatable decorative panel system and heatable panel

Abstract

The present invention is related to a heatable decorative panel system and a panel for use in such system. The invention is further related to a decorative covering comprising a plurality of connected panels. The invention is also related to a method for installing a system according to the invention and a kit of parts.

Description

[0001] Heatable decorative panel system and heatable panel

[0002] The present invention is related to a heatable decorative panel system and a panel for use in such system. The invention is further related to a decorative covering comprising a plurality of connected panels. The invention is also related to a method for installing a system according to the invention and a kit of parts.

[0003] Over the past couple of decades, the use of heat and the way of heating places has evolved a great deal. Especially in the recent years, efficiency of heating has been a major point of attention. This has caused more and more complicated heating techniques to have been adopted.

[0004] An example of one of these systems is the regular type of underfloor floor heating. These floor heating systems generally comprise a series of pipes for guiding warm water, wherein said pipes are embedded in an underfloor floor substrate, which typically is a concrete floor. Alternatively, electric heating mats of sorts are embedded in such underfloors. When used, these pipes or mats heat up the surrounding underfloor material, and hence a (top) flooring installed on top of said underfloor, causing the floor surface of said (top) flooring to radiate heat into the living space. It has been found that such techniques are superior in terms of efficiency over the standard radiators for the most part. However, this kind of floor heating system come at a high investment cost, installation complexity, a generally slow response time, and potentially uneven heat distribution.

[0005] Sometimes, however, this form of heating is not suitable e.g. from a constructional point of view and / or an energy efficiency point of view. This may for example be the case if heat is only required for a limited amount of time, such as several hours or even less. Underfloor heating, but also other types of heating systems are generally thermally slow due to the thermal mass required to heat up and often requires modification of the underfloor which may be complicated for existing underfloors.

[0006] Alternative replacement heating systems exist which are mounted or installed on top of and / or above the top flooring, which may, for example, be in the form of an electric heater. However, such a solution may not be visually pleasing, and consumes quite some energy. It is therefore a first goal of the present invention to provide an improved floor design which is simpler and / or more robust.

[0007] It is a second goal of the present invention to provide an improved floor design which allows easy and flexible installation.

[0008] It is a third goal of the present invention to provide a more energy efficient heating system.

[0009] At least one of these goals can be achieved by the invention. The present invention thereto proposes a heatable decorative panel system, in particular a heatable decorative wall panel system, a heatable decorative ceiling panel system, a heatable floor panel system, or a heatable decorative furniture panel system, comprising: a plurality of decorative panels, wherein the panels, preferably each panel, comprise: o a core layer having a top surface and a bottom surface, o a decorative top structure affixed, directly or indirectly, onto said top surface of the core layer, at least one heating structure, in particular at least one ohmic heating structure, affixed, directly or indirectly, onto said bottom surface of the core layer o at least one first panel edge having a first coupling profile, and at least one second panel edge having a second coupling profile, wherein the first and second coupling profile are configured to co-act such that two panels can be coupled at the first and second edges, Due to the coupling profiles the panels may be easily mechanically interconnected such as to form a covering. To this end, it is preferred that the first and second panel edge are arranged on opposing sides of a panel. By allowing panels to be coupled a modular system may be obtained. The heating structure, which is typically an ohmic heating structure, may provide for a relatively robust heating system which requires a low amount of energy to generate heat to a surrounding.

[0010] The decorative top structure may and typically will hide the heating structure from sight of a user (looking at a top surface of the panel(s)). To this end the heating system according to the invention may be applied in various purposes. For example, the panels may form wall panels, or ceiling panels. However, the panels may also form furniture panels, such as for use as a desk, or a door. However, the invention is not limited to aforementioned purposes. The decorative top structure may to this end provide the desired aesthetic appearance of the panels. For example, the decorative top structure may provide the appearance of tiles, e.g., when used in a bathroom wall.

[0011] The heating structure, in particular the ohmic heating structure, is applied to the bottom surface of the core layer. This facilitates the production of the panel compared to a panel wherein a heating structure would be applied in between the core layer and the decorative top structure. The heating structure is preferably positioned below (a bottom surface of) the coupling profiles of the panel. In this manner, the heating structure is shielded both by the core layer and the decorative top structure from a top surface of the panel, which reduces the risk that the heating structure will be exposed to water applied onto a top surface of the panel. The co-acting coupling profiles of adjacent panels realize a further water barrier (water labyrinth) to impede water to seep through a seam formed in between interconnected panels. Optionally, this water barrier can further by improved by gluing the coupling profiles to each other in the interconnected state and / or by applying at least one hydrophobic agent onto and / or into one or both coupling profiles.

[0012] Preferably, at least two mutually separated electrical contact pads, connected or connectable to said heating structure, are provided, wherein said contact pads are preferably entirely positioned at a side of the core layer facing away from the top surface of the core layer. In general, these contact pads may form the contact points for establishing an electric heating circuit. That is, when an optional power source is connected to both of the contact pads a current circuit is formed between the power source, contact pads and the ohmic heating structure. Such contact pads may be in the form of a positive or negative pole, or an anode and cathode, or electrodes. Due to the ohmic resistance of the heating structure, heat is generated by the heating structure.

[0013] Optionally, at least one connecting element, for at least electrically connecting contact pads of adjacent panels, at least in a coupled condition, is provided and makes part of the panel system according to the invention. Such a connecting element preferably electrically connects a contact pad of a first panel with a contact pad of a second panel. Via said connecting element the connected contact pads of adjacent panels may form a single electrode. The connecting element contributes to a relatively easy and robust coupling of panels in the heatable panel system to increase the effective heating surface and hence the heat emission of the total system. Each connecting element may be formed by a separate component of the panel system according to the invention. Each connecting element may attached, preferably releasably attached, to the heating structure of the panels, in particular to the heating structure of at least two mechanically interconnected panels to electrically interconnect said heating structures. Preferably, the connecting element may be attached to the contact pads of the decorative panels The mechanical coupling of adjacent panels stabilizes and secures the electrical connection between adjacent heating structures.

[0014] The heatable decorative panel system according to the invention is particularly easy to place, without need for expensive equipment. In addition, the solutions provided for are robust and modular such that the size of the heatable decorative panel system may be easily adapted according to the need of the user.

[0015] At least one contact pad, preferably the at least two contact pads, may form a track, in particular an elongated track. It is also conceivable that at least one contact pad, preferably each contact pad, stretches along at least a portion of at least one panel edge of at least one decorative panel, preferably at least one of the first and / or second panel edge. It was found that this increases the potential effectivity of the heat generation of the heatable decorative panel system. In particular since the flow of current through the ohmic heating structure may be more uniform along the panel resulting in a more uniform ohmic heat that can be generated. To further increase this effect, the two contact pads may be arranged at opposing panel edges of at least one decorative panel. At least one contact pad, in particular formed as a track, has a width between about 25mm and 100m, preferably about 50mm. This was found to be ideal for establishing both good conductive properties, i.e., preventing undesired losses in the contact pad, as well as providing a good contact portion for connecting a connecting element thereto. Preferably, wherein at least one pair contact pads of at least one decorative panel are spaced apart about 180mm to 1200mm, preferably about 600mm to 1000mm, in particular about 820mm. Preferably, the two contact pads are allocated at opposing panel edges.

[0016] It is imaginable that at least a portion of the heating structure, preferably the entire heating structure, and the contact pads are integrally formed. Integrally formed in this context may be understood as formed out of the same material and subsequently unified. This is for example the case when the contact pads and heating structure are applied in different manufacturing steps but form a single entity due to, for example, heat in the process of applying the heating structure which causes the contact pads to form integrally with said heating structure. However, it may also be understood as the heating structure and contact pads being formed in a single and preferably consecutive processing step, causing the contact pads and heating structure to be integrally connected. The integrally formed heating structure and contact pads may increase the robustness of the panel, since the contact, in both electrical and mechanical sense, is properly provided for.

[0017] At least a portion of the at least one contact pad may be formed by a conductive strip, in particular a self-adhesive conductive strip. Preferably, the conductive strip, in particular the self-adhesive conductive strip, is an aluminium and / or copper strip. By using a conductive strip, in particular a self-adhesive conductive strip, an affordable contact pad may be achieved. Due to the self-adhesive properties the contact pads may be applied relatively easily. Preferably, said conductive strip is applied directly to a bottom surface of the core layer. The conductive strip may be applied directly onto the bottom surface of the core layer. In the case of a self- adhesive conductive strip, directly applied may be understood as the adhesive side of the conductive strip being in contact with said bottom surface of the core layer. It is preferred that the adhesive is at least partially conductive. Preferably, the conductive strip comprises conductive particles dispersed within said adhesive. These conductive particles may at least partially be composed of at least one material chosen from the group of: graphite, aluminium, silver, copper, graphene, carbon, Nichrome (nickel-chromium alloy), Constantan (copper-nickel alloy), stainless steel, and mixtures of at least two of these materials.

[0018] The thickness of at least one contact pad, in particular the (self-) adhesive conductive strip, may be situated between about 0.01 mm and about 0.2 mm, preferably between about 0.025 mm and about 0.12 mm. Since the contact pad and / or conductive strip is relatively thin, the bottom side of the panel is relatively unobstructed by application of the present invention. The thickness allows for a sufficient conduction of electricity, whilst preventing losses in said contact pads in order to prevent conductive losses towards the heating structure.

[0019] The heating structure of at least one decorative panel may at least partially be formed by at least one layer. It is also conceivable that the heating structure comprises a plurality of layers. If the heating structure is formed by a plurality of layers, the layers may be mutually different. It is imaginable that the ohmic heating structure comprises at least one carrier layer, preferably composed of an electrically insulating material, and at least one resistive heating track and / or at least one resistive heating layer (and / or any other heat generating structure) supported and / or carried by said carrier layer. The at least one resistive heating track and / or resistive heating layer may be applied onto an outer surface of the carrier layer, optionally by means of a heat-resistant glue, such as polyurethane based glue, and / or optionally by means of deposition. Additionally or alternatively, the at least one resistive heating track and / or the at least one resistive heating layer may be integrated, such as incorporated and / or penetrated and / or embedded and / or dispersed, within the carrier layer. The carrier layer may be a woven structure and / or a non-woven structure. It is imaginable and it may even be preferable that in case one or more resistive heating tracks are used, that these heating tracks could be woven and / or stitched into the carrier layer. To this end, it is favourable in case the heating track(s) is / are formed by heating wires. Each heating track may be formed by a single heating wire, although it may also be preferable that each heating track is formed by a plurality of the heating wires, wherein the heating wires of each heating track may e.g. run in parallel. These heating wires may be at least partially composed of a metal alloy with high electrical resistance and thermal durability, such as Nichrome (nickel-chromium alloy), Constantan (copper-nickel alloy), copper, aluminium, and / or stainless steel. Alternative non- metal materials are also conceivable, such as carbon. These materials are selected for their ability to efficiently convert electrical energy into heat while maintaining structural stability under varying thermal conditions. The wire can be woven or embedded into the carrier layer in patterns such as a grid, meander, sinusoidal, or spiral to optimize heat distribution and performance. Additionally, the wire's diameter and resistance can be adjusted to control the heating output for specific applications. The wires may be provided by an electrically insulating and preferably heat conductive coating or other type of shielding to prevent short-circuiting in humid conditions. Insulation enhances safety and prevents short circuits. As an alternative, the fibers could be uninsulated but separated by an insulating mesh to prevent contact. The carrier layer of the heating structure could be a flexible, durable, and non-conductive material capable of withstanding high temperatures and mechanical stress. It is imaginable that the carrier layer is at least partially composed of silicone-coated fiberglass fabric, which offers excellent heat resistance and insulation, polyimide film (e.g., Kapton) for its lightweight and high dielectric strength, or polyester fabric and / or any other polymer with a heat-resistant coating for a more economical choice. In case the carrier layer is at least partially composed of at least one polymer, such as a thermoplastic and / or a thermoset, this polymer may be a recycled polymer, a virgin polymer, or mixture of both. (Other) fabrics or non-fabrics, and / or other textiles or non-textiles are also imaginable. It is imaginable that the carrier layer comprises natural fibers. Examples of suitable natural fibers are: cotton fibers, coir fibers, kapok fibers, hemp fibers, jute fibers, flax fibers, sisal fibers, abaca fibers, wool fibers, kenaf fibers, bamboo fibers, palm fibers, animal leather fibers, and mixture of two or more of these fiber types. The fibers may be recycled fibers and / or virgin fibers. These materials provide a stable base for embedding conductive heat resistive wires while maintaining electrical insulation and structural integrity under thermal cycling. As will be indicated below, the carrier layer may also be formed by a paper sheet or ((thermo)plastic) foil. The carrier layer preferably has a thickness of between 0.3 and 0.8 mm, more preferably between 0.4 and 0.5 mm.

[0020] It is not required that the plurality of layers is directly stacked on top of each other. It may well be the case that at least two layers are mutually separated by an intermediate layer formed out of different material. Preferably, at least one layer of the heating structure comprises at least one heating layer and / or is entirely formed by a heating layer. The heating layer is preferably an ohmic heating layer (resistive heating layer) and / or an inductive heating layer. The heating structure may comprise dispersed graphite and / or graphene and / or carbon particles. Said particles may be dispersed within the material, preferably within the layer. This provides a suitable resistivity of the heating structure which may render it suitable for ohmic heating. It is conceivable that at least a portion of the heating structure, preferably at least one layer and / or at least one heating track of the heating structure, is printed. Particularly digitally printed. By printing, in particular digitally printing, a portion of the heating structure, such as a layer thereof, a relatively easy application is possible. Also, printing allows for providing a layer of consistent thickness which allows for a more uniform heat generation over a panel since the resistivity of the whole heating structure may be more homogeneous. Moreover, this allows the technical advantage of precise control over the heating pattern and resistance through printing techniques, allowing for customized heat distribution. An alternative embodiment could use a sprayed-on conductive coating instead of a printed layer. It is also conceivable that the heating structure is at least partially formed by a heating paper and / or heating foil. Such heating paper and / or heating foil may be attached, preferably releasably attached, to the bottom side of the panel, in particular the bottom surface of the core. Preferably, said layer is attached by means of an adhesive, preferably a conductive adhesive. Said adhesive may be a pressure-sensitive adhesive, being a nonreactive adhesive which forms a bond when pressure is applied to bond the adhesive with a surface. No solvent, water, or heat is needed to activate this adhesive.

[0021] According to an embodiment, the ohmic heating structure of at least one decorative panel is at least partially defined by and / or comprises at least one ohmic heating network and / or ohmic heating pattern. This arrangement offers the advantage of uniform heat distribution across the panel surface. The ohmic heating network and / or ohmic heating pattern may comprise a plurality of mutually spaced apart ohmic heating traces (heating tracks or heating fibers), wherein each ohmic heating trace extends between the at least two mutually separated electrical contact pads. This configuration allows for efficient current flow and even heating. An alternative could use a fractal-like branching pattern of heating traces for more complex heat distribution. Preferably, at least two, preferably all spaced apart ohmic heating traces are mutually parallel. The heating traces may at least partially be linear, and / or may at least partially be angular and / or curved, in particular sinusoidally curved. Parallel traces provide consistent heat output across the panel. As an alternative, the traces could be arranged in a concentric pattern for circular or oval panels. Preferably, at least one pair of adjacent spaced apart ohmic heating traces, preferably all pairs of adjacent spaced apart ohmic heating traces, are connected via at least one ohmic heating bridge element, preferably a plurality of spaced apart ohmic heating bridge elements. Bridge elements improve current distribution and provide redundancy. Alternatively, the traces could be interconnected using a diagonal cross-hatch pattern instead of distinct bridge elements. Said at least two ohmic heating bridge elements are preferably spaced apart by approximately 3mm to 45mm, preferably 15mm to 45mm, more preferably 30mm. This spacing improves redundancy and material usage. An alternative could use progressively increasing spacing between bridge elements from the panel center to the edges. Preferably, at least one ohmic heating trace has a width of approximately 10- 30mm, and wherein at least two adjacent, preferably all adjacent ohmic heating traces are spaced apart by approximately 3mm to 45mm, preferably 15mm to 45mm, more preferably 30mm. These dimensions balance effective heating with panel flexibility. An alternative could use traces with varying widths, wider at the panel edges and narrower in the center, to compensate for heat loss at the edges. Additionally or alternatively, it may be preferred that the ohmic heating trace(s) (and / or heating track(s) and / or heating fiber(s)) are positioned at a distance from at least one pair of opposite panel edges, and preferably at a distance from all panel edges to reduce heat loss at the edges and / or to secure a more evenly distribution of heat release. The distance between each edge and the at least one heating trace may be at least 1 cm, preferably at least 2 cm or at least 3 cm, such as 5 to 7 cm. Hence, in case of a panel have a width of 90 cm the effective width of the heating trace(s) can be 75-80 cm, allowing a heating trace free edge zone having a width of 5 to 7.5 cm to be applied. This preferably also applies in length direction, wherein the panel length may vary but is typically situated in between 100 and 265 cm. If ohmic heating fibers are applied, it may be preferred that at least a fraction of these heating fibers have a diameter or thickness of approximately 0.1 mm up to 1.0 mm, preferably up to 0.8 mm. This size range provides effective heating while maintaining flexibility. An alternative could use a combination of thicker and thinner fibers to create zones of varying heat output. Said conductive ohmic heating fibers may form at least one resistive heating mesh, preferably a woven mesh. Each mesh may defined a single heating track. A mesh provides uniform heat distribution and structural strength. The mutually separated electrical contact pads are preferably at least partially, preferably entirely formed by the ohmic heating fibers. Using fibers for contact pads simplifies manufacturing. Optionally, the fiber ends could be gathered and crimped into separate metallic contact pads for improved electrical connection and / or could also be crimped directly together with an electric power cable (typically having a length of 2-5 m and / or having a 48V connector at a distal end).

[0022] It is imaginable that the contacts and the heating structure are integrated. It is imaginable that the contacts and the heating structure are formed out of the same material.

[0023] The ohmic resistance of the heating structure may vary, and may dependent on the design of the heating structure, in particular of the materials used for the heating structure and the dimensioning of the heating structure and possibly of the temperature of the heating structure. It was found that a resistance of 4-6 ohm, such as 4.6 to 5 ohm, in particular 4.8 ohm, is well suitable to heat up a top surface of the panel to a temperature of 40 to 50 degrees Celsius. The heating structure may be powered by various electrical power sources, but typically a 48 Volt power source is preferably used. A 48 V system (in particular 48 V DC system) having operating with at least one 48 V DC power source is classified as a low-voltage power system (below 60V), which reduces the risk of electrical shock and makes it safer for use in residential and commercial environments compared to higher voltage systems. At 48V, power transmission losses are minimized compared to lower-voltage systems (e.g., 12V or 24V), while avoiding the complexities of high- voltage systems. This ensures efficient delivery of power to the heating structure. Moreover, using a 48V system enables the heating structure to be scaled up or down in size without significant modification to power delivery systems, making it suitable for various panel dimensions and heating requirements. It is imaginable that the power source is an adjustable power source to regulate and control the heat generation and heat release of the panel(s). More in particular, an adjustable power source for a heating structure allows precise control of the heating output by enabling dynamic adjustment of voltage, current, or power delivery through mechanisms such as voltage regulators, current controllers, or pulse-width modulation (PWM). This flexibility ensures energy efficiency by providing only the necessary power to maintain the desired temperature, while also enhancing safety by preventing overheating through thermostatic feedback. The adjustable power source can be integrated with smart systems for remote control and programmability, offering compatibility with various applications, including floor heating and wall panels. The heating structure of at least one decorative panel may be at least partially covered by a coating and / or layer, preferably an electrically insulating coating and / or layer. It is also possible that the heating structure comprises a coating, preferably an electrically insulating coating. Hence, the coating or layer may be part of the heating structure, or may cover the heating structure. The coating may increase the thermal efficiency of the heating structure. Particularly if the coating is electrically insulating, it may prevent at least partially that the heating structure makes electrical contact with a surrounding, and thereby causing a loss of heat generation. In addition, it has surprisingly been found that if such a coating and / or layer is provided on top of the heating structure more heat is emitted from the side of the panel facing away from the heating structure. The coating may reflect at least a portion of the heat emitted in a direction out of the bottom side of the panel towards a direction out of the top side of the panel, hence allowing more heat to be emitted into a zone and / or area to be heated. It was particularly observed that if the coating, in particular the insulating coating, comprises at least one polymer material, in particular polyurethane the heating properties improved. Preferably, the coating, in particular the insulating coating, is at least partially formed by a varnish and / or lacquer. Said coating and / or layer, in particular the insulating coating, has a thickness is situated between 10 and 50 micron, in particular about 20 micron. Preferably, the coating is applied at a weight of about 20 mg per square meter. However, the application of the coating may vary between 10 mg per square meter and 50 mg per square meter. Due to the insulating properties the heating structure, particularly if formed by a heating layer, is not prone to undesired contact. Therefore, increasing the safety of the product, as well as the thermal efficiency. Preferably, the coating covers at least a significant portion of the heating structure, preferably at least 75%, more preferably at least 85%.

[0024] The heating structure may cover at least a portion at least one contact pad, preferably at least 75%, more preferably at least 85% of at least one contact pad. Preferably, at least a small portion of at least one contact pad, preferably each contact pad, remains uncovered by the heating structure. Said uncovered portion may form between 0.1% and 15% of the surface area of the contact pad, preferably about 5% to 10% of the surface area of the contact pad. This allows to establish an electrical connection between the contact pads and the connecting element during installation on a relatively easy manner. If an insulating coating or layer is provided onto the heating structure, it is conceivable that said coating or layer covers essentially the entire heating structure, provided that at least a portion the contact is uncovered by said heating structure.

[0025] The thickness of the heating structure may be situated between 10 micron and 100 micron, preferably between 25 micron and 75 micron, more preferably about 50 micron. Preferably, the heating structure is applied in a weight of about 50 mg per square meter, however the weight may vary between about 10 mg per square meter and 100 mg per square meter. This thickness was found sufficient to establish the conductive and resistive properties that allow the heating structure to function as an ohmic heating structure. Preferably, the heating structure is formed by a single layer, in particularly a printed layer, which has a thickness of about 50 micron. It is conceivable that the thickness may be adapted such that the resistive and conductive properties fit the dimension of the surface area of the covering formed by the system of the present invention.

[0026] The heating structure may be provided essentially only on a bottom surface of the core layer. As such, the heating structure is well protected from undesired impact. Hence, the heating structure may be allocated entirely and / or only on a downward facing surface of the panel, particularly the core layer. By protecting the heating structure from abrasive impact, it may last for longer which is better from an economic and ecological point of view.

[0027] At least one connecting element may comprise a first adhesive portion and a second self-adhesive portion, wherein said first and second self-adhesive portion are each connectable to a contact pad. This may allow to establish an electrical connection between the connecting element and the contact pad on a relatively easy and simple manner and may allow for a better ease of use of the system. More importantly, it may increase the ease of installation of the system significantly. At least one connecting element may be formed by an electrically conductive self- adhesive strip. The conductive (self-) adhesive strip may be the same strip as the one forming the contact pad. Preferably, the conductive strip, in particular the self- adhesive conductive strip, is an aluminium and / or copper strip and / or a stainless steel strip and / or a Nichrome (nickel-chromium alloy) strip and / or a Constantan (copper-nickel alloy) strip. By using a conductive strip, in particular a self-adhesive conductive strip, a simple and robust contact between the connecting element and the contact pad may be achieved. Due to the self-adhesive properties the connecting elements may be applied relatively easily. Preferably, the self-adhesive conductive strip comprises conductive particles dispersed within said adhesive. These conductive particles may at least partially be composed of at least one material chosen from the group of: graphite, aluminium, silver, copper, graphene, carbon, Nichrome (nickel-chromium alloy), Constantan (copper-nickel alloy), stainless steel, and mixtures of two or more of these materials. Graphene and graphite are related but distinct materials; graphite is a naturally occurring form of carbon composed of many layers of graphene stacked together, while graphene is a single, one-atom-thick layer of carbon atoms arranged in a hexagonal lattice, giving it unique properties like exceptional strength, electrical conductivity, and flexibility.

[0028] At least one connecting element may be at least partially formed by an electric wire, wherein at least a portion of said wire is electrically insulated, and a first and / or second end of said wire is uninsulated. The insulated portion of the wire may for example be formed by a polymer enclosure of the wire. Said uninsulated first and / or second end portion is connected or connectable to at least one contact pad of adjacent panels, for mutually electrically connecting the contact pads of adjacent panels and / or wherein at least one uninsulated portion is provided with a clamp. The uninsulated portions thus may allow for establishing an easy electrical connection between the connecting element and a contact pad. The connecting element may also be formed by two of such wires, wherein each wire is connected to one panel, and mutually connected to each other for establishing a connection between panels. The clamp may for example be attached to the uninsulated portion facing away from the uninsulated portion connected or connectable to the panel. The electrical may be achieved by mutually connecting said clamps.

[0029] It is imaginable that at least one connecting element is connected to a contact pad of at least one panel, the connecting element may be partially pre-installed.

[0030] Partially pre-installed may for example be understood as one side of the connecting element being adhered to the panel, in particular a contact pad thereof. The uninsulated second end of the connecting element may be provided with a peel covering. Said covering protects the adhesive from adhering unintentionally. During installation, the peel may be peeled off from said second end to expose the adhesive and may be connected to a contact pad of an adjacent panel. This allows the adjacent contact pads of adjacent panels to be electrically connected such as to form a single conductor. If the connecting element is formed by a wire, the preinstallation may be established similarly, for example by electrically connecting an uninsulated first end of the wire to the contact pad of a panel. It is imaginable that the wire is electrically connected to a contact pad via spot-welding, however, may also be connected via a self-adhesive conductive tape.

[0031] Preferably, the connecting element is provided, preferably entirely provided, onto a bottom side of the panel. In particular, the connecting element is exclusively or only provided onto a bottom side of a panel. This may prevent that the connecting element has to be arranged in and / or near the coupling profiles of the panel and therefore is an easier and more robust solution. Typically, if a contact element were to be provided onto, or near, a coupling profile several potential problems arise. Firstly, the chance of electrical short circuit greatly increases. Particularly since any moisture spilled from a top side of the panel may easily enter the coupling profiles. Obviously the is not desired. Secondly, the coupling profiles of panels are generally quite complex, particularly in terms of dimensioning, adding a delicate layer such as a connecting element may complicate the coupling of adjacent panels, which is also undesired. Thirdly, connecting elements require to establish a reliable electrical connection. The coupling profiles, as discussed, are prone to some dimensioning accuracy, which may cause the connecting elements to make a bad electrical contact which is not beneficial in terms of the heat generation of the system. To this end, the present invention teaches to apply the connecting element on the bottom side of the panel exclusively. Not only does this increase the moisture resistance, as the connecting element is further away from the exposed top side of the panel, it also allows for establishing an easy and reliable electrical connection between adjacent panels. Preferably, a first and / or second panel side edge, preferably each panel side edge, of at least one panel are essentially free of heating structure and / or connecting element. Here, the side edge may be understood as the side of the panel provided with a coupling profile, i.e., a side of the panel which extends perpendicular to the bottom or top side of the panel. Particularly, the surface area stretching between the top surface and the bottom surface of the panel.

[0032] Preferably at least one connecting element is connected, directly or indirectly, to a portion of at least one contact pad which is free of heating structure, in particular an exposed portion of at least one contact pad. As such, the connecting element may be easily provided onto a panel after production of a panel, without requiring to locally remove material.

[0033] At least one connecting element, at least in a condition coupled to a contact pad, may be bendable, particularly between 0 degrees and 180 degrees, more particularly about 90 degrees. Said bendable connecting element is preferably at least bendable around an axis which is substantially parallel to at least one edge of the panel, preferably an edge along which adjacent panels are coupled. However, it is also conceivable that the connecting element is, in addition or alternatively, bendable around an axis which is substantially orthogonal to the edge of the panel, particularly orthogonal to the edge along which adjacent panels are connected. Said latter axis is preferably situated in the plane formed by a bottom side of the panel. This increases the flexibility of the system according to the present invention. Hence, the panels may be installed in a corner as the connecting element allows for making an electrical connection between adjacent panels which are not in the same plane. It is imaginable that at least one portion of at least one connecting element is connected to a contact pad, and a second portion of at least one connecting element is movable with respect to the panel. Hence, the connecting element is preferably at least partially movable and thus not entirely fixated to a bottom side of the panel. This may allow for some degree of movement of adjacent panels.

[0034] A bottom side of at least one panel, in particular a bottom surface of the core layer, may be provided with one or more spacers. Said spacers may allow to maintain a regulated distance between the bottom surface of the panel or core with respect to a substrate onto which the panels are provided. Hence, the substrate may be a wall, a ceiling, a door, a floor, or the like. By maintaining a predefined distance, it may be realized that the heating efficiency is further improved as the air which is trapped between the back side of the panel and the substrate may form as an insulating layer. It is imaginable that at least one spacer is at least partially formed by one or more recesses and / or one or more protrusions on or in a bottom side of said panel, in particular a bottom surface of the core layer. Preferably, said one or more recesses and / or protrusions are mutually spaced apart. These recesses may, for example, be formed by cells and / or grooves, applied in the bottom surface of the core layer. The recesses may be present across the entire bottom surface, but it may also be imaginable and even preferable that the recesses are only present in a centre section of the bottom surface and not in a surrounding peripheral edge section of the bottom surface in order to preserve the mechanical strength of the coupling profiles. Preferably, at least one spacer, and optionally at least one recess and / or protrusion, is applied on or in a bottom surface of the core layer, and wherein at least a portion of the heating structure at least partially follows the relief structure of the bottom side of the panel, in particular the bottom surface of the core layer. Hence, the heating structure may have a different height levels, which also increases the effective heating surface of the heating structure. Here, the spaces forming the recesses or the spaces enclosed by the protrusions may form the insulating spaces. These spaces may further improve the sound-dampening properties of the panels of the panel system according to the invention. By allowing the heating structure to follow the bottom side of the core layer, and hence have lower and higher regions, a larger surface area of the heating structure may be achieved, which may be beneficial in terms of the total heating power per square meter.

[0035] It is also imaginable that at least one panel comprises a backing layer, said backing layer applied at a side of the heating structure facing away from the core layer. Said backing layer shall be distinguished from the core layer, and as such does not provide the strength and rigidity to the panel. One or more spacers and / or recesses and / or protrusions may be provided in said backing layer, preferably wherein at least a portion of the heating structure at least partially follows the relief structure of the bottom side of the panel, in particular the backing layer. This may provide the same benefits as presented with respect to the spacers applied into the panel, particularly the core layer. Also here, at least one spacer and / or recess may be at least partially formed by a cavity and / or groove and / or air pocket, preferably formed at a side of the heating structure facing away from the core layer. Hence, an increased surface area of heating structure may also be achieved in this embodiment which may be beneficial to the heating power per square meter.

[0036] The heatable decorative panel system may comprise at least one power supply, for powering of the ohmic heating structure, particularly via the contact pads. To this end, at least two contact pads may be provided with a power connection, for connecting of a power supply to said contact pads via the power connections. It is conceivable that a plurality of panels are mutually connected in series, preferably via one or more connecting elements, and wherein a plurality of panels are mutually connected in parallel, preferably via one or more power connections. By arranging a predefined number of panels in series and / or parallel the system may be more efficiently powered. Preferably, the heatable decorative panel system further comprises at least one power transformer for transforming of a supply voltage from 110 - 120V or 220 - 240V, particularly 230V, to a used voltage of 48V or 24V if an alternating current is used. Direct current may be used up to 75 V. Preferably, the transformer supplies this voltage at 10 Ampere, resulting in a power of about 480 to 500 Watt. This current meets the General Product Safety Directive 2001 / 95 / EC (or equivalent thereof). Said power transformer may be either separate, or part of at least one panel. Only a single power transformer is required for transforming of the power towards the panels. However, it may be possible to provide each panel with its own power transformer. Using a power transformer makes the system compliant for use in e.g., a bathroom within zone 1 , in line with DIN VDE 0100 Teil 701 (VDE 0100-701 ): 2008-10 or an equivalent thereof.

[0037] It is preferred that the core layer is at least partially composed of electrically insulating material. This will prevent undesired flow of current through the core layer. Moreover, it increases the distance between an exposed side of the panel and the electric circuit arranged thereon, further increasing the safety of the present invention. Optionally, the decorative top structure comprises o at least one, preferably digitally printed, decorative layer forming at least one decor image, and o at least one transparent and / or translucent protective layer covering said decorative layer. It is conceivable that the heating structure comprises, or is substantially entirely formed of, material having a positive temperature coefficient (PTC). The PTC material's inherent property of increasing resistance as temperature rises ensures that the heating element's power dissipation is automatically adjusted. This dynamic adjustment prevents the heating structure from exceeding either a predetermined temperature threshold, or preventing it from overheating. This would make the present invention suitable for various applications where temperature control is important. The material may be partially formed out of the non-limitative group consisting of: Barium Titanate, polyethylene with carbon black dispersed particles, polymeric PTC thermistors, ceramic PTC thermistors.

[0038] The present invention is also related to a heatable decorative panel covering, in particular a wall panel covering, consisting of mutually coupled heatable panels of the heatable decorative panel system according to any of the preceding claims, in particular wherein contact pads of two adjacent panels are connected via at least one connecting element. The same benefits as elaborated above with respect to the heatable decorative panel system apply to the covering as well. Preferably, the covering has a surface area of about 1 m2 to 10m2, in particular about 5m2. At least during use, the covering according to the present invention has a power consumption of about 0.5kW / hr. It was found that this is proven sufficient to heat up a room of about 30 square meters. The covering may reach a temperature of about 40 degrees Celsius. Yet, if a smaller surface area is used with the same power, the power may be more concentrated causing a higher temperature to be reached.

[0039] The invention is further related to a kit of parts, comprising a plurality of heatable decorative panels according to the invention, one or more connecting elements according to the invention, and optionally, at least one power supply preferably comprising a power transformer. The invention may further be related to a connecting element according to the present invention. The connecting element preferably comprising at least two self-adhesive portions. At least one, preferably both, self-adhesive portions having an adhesive with conductive particles, in particular graphite, and / or graphene, and / or carbon particles, dispersed therein. According to a different aspect, the present invention is related Method for installing a heatable decorative panel system according to the invention, comprising the steps of: a) providing at least one first decorative panel on a supporting surface, in particular a wall, b) providing at least one second decorative panel, c) connecting at least one first end portion of a connecting element to at least one contact pad of said panel, d) connecting at least one second end portion of the connecting element to at least one contact pad of a different panel, e) coupling the first and second panel, in particular via the first and second coupling profiles thereof f) optionally, connecting at least one power supply to the contact pads. The same benefits as explained with respect to the heatable decorative panel system apply to the method as well. The invention is yet further related to a decorative panel for use in a panel system according to the present invention.

[0040] Further embodiments of the invention are presented in the non-limitative set of clauses presented below.

[0041] 1 . Heatable decorative panel system, in particular a heatable decorative wall panel system, a heatable decorative ceiling panel system, a heatable floor panel system, or a heatable decorative furniture panel system, comprising: a plurality of decorative panels, wherein the panels, preferably each panel, comprise: o a core layer having a top surface and a bottom surface, o a decorative top structure affixed, directly or indirectly, onto said top surface of the core layer, o at least one ohmic heating structure affixed, directly or indirectly, onto said bottom surface of the core layer, o at least two mutually separated electrical contact pads, connected or connectable to said heating structure, wherein said contact pads are preferably entirely positioned at a side of the core layer and / or at a side of the heating structure facing away from the top surface of the core layer, o at least one first panel edge having a first coupling profile, and at least one second panel edge having a second coupling profile, wherein the first and second coupling profile are configured to co-act such that two panels can be coupled at the first and second edges, and preferably at least one connecting element, for at least electrically connecting contact pads of at least one panel, preferably adjacent panels in a coupled condition, wherein said connecting element is preferably positioned, more preferably entirely positioned, at a side of the core layer and / or at a side of the heating structure facing away from the top surface of the core layer.

[0042] 2. Heatable decorative panel system according to clause 1 , wherein at least one contact pad, preferably the at least two contact pads, form a track, in particular an elongated track.

[0043] 3. Heatable decorative panel system according to clause 1 or 2, wherein at least a portion of the heating structure, preferably the entire heating structure, and the contact pads are integrally formed.

[0044] 4. Heatable decorative panel system according to any of the preceding clauses, wherein at least one contact pad, preferably each contact pad, stretches along at least a portion of at least one panel edge of at least one decorative panel, preferably at least one of the first and / or second panel edge.

[0045] 5. Heatable decorative panel system according to any of the preceding clauses, wherein the two contact pads are arranged at opposing panel edges of at least one decorative panel.

[0046] 6. Heatable decorative panel system according to any of the preceding clauses, wherein at least one contact pad, in particular each contact pad, is a printed contact pad.

[0047] 7. Heatable decorative panel system according to any of the preceding clauses, wherein at least a portion of the at least one contact pad is formed by a conductive strip, in particular a self-adhesive conductive strip. 8. Heatable decorative panel system according to clause 7, wherein the conductive strip, in particular the self-adhesive conductive strip, is an aluminium and / or copper strip.

[0048] 9. Heatable decorative panel system according to clause 7 or 8, wherein a thickness of the conductive strip, in particular the self-adhesive conductive strip, is situated between about 0.01 mm and about 0.2 mm, preferably between about 0.025 mm and about 0.12 mm.

[0049] 10. Heatable decorative panel system according to any of the preceding clauses, wherein the heating structure of at least one decorative panel is at least partially formed by at least one layer.

[0050] 11 . Heatable decorative panel system according to clause 10, wherein at least one layer is a resistive heating layer, preferably a printed resistive heating layer.

[0051] 12. Heatable decorative panel system according to any of the preceding clauses, wherein the ohmic heating structure of at least one decorative panel is at least partially defined by and / or comprises at least one ohmic heating network and / or ohmic heating pattern.

[0052] 13. Heatable decorative panel system according to clause 12, wherein the ohmic heating network and / or ohmic heating pattern comprises a plurality of mutually spaced apart ohmic heating traces, wherein each ohmic heating trace extends between the at least two mutually separated electrical contact pads.

[0053] 14. Heatable decorative panel system according to clause 13, wherein at least two, preferably all spaced apart ohmic heating traces are mutually parallel.

[0054] 15. Heatable decorative panel system according to clause 13 or 14, wherein at least one pair of adjacent spaced apart ohmic heating traces, preferably all pairs of adjacent spaced apart ohmic heating traces, are connected via at least one ohmic heating bridge element, preferably a plurality of spaced apart ohmic heating bridge elements. 16. Heatable decorative panel system according to clause 15, wherein at least two ohmic heating bridge elements are spaced apart by approximately 3mm to 45mm, preferably 15mm to 45mm, more preferably 30mm.

[0055] 17. Heatable decorative panel system according to any of the clauses 13-15, wherein at least one ohmic heating trace has a width of approximately 30mm, and wherein at least two adjacent, preferably all adjacent ohmic heating traces are spaced apart by approximately 3mm to 45mm, preferably 15mm to 45mm, more preferably 30mm.

[0056] 18. Heatable decorative panel system according to any of the preceding clauses, wherein the ohmic heating structure is at least partially formed by and / or comprises ohmic heating fibers.

[0057] 19. Heatable decorative panel system according to clause 18, wherein said ohmic heating fibers are stitched into and / or glued onto the bottom side of the core layer.

[0058] 20. Heatable decorative panel system according clause 18 or 19, wherein said ohmic heating fibers have a diameter or thickness of approximately 0.1 mm up to 1 .0 mm, preferably up to 0.8 mm.

[0059] 21 . Heatable decorative panel system according any of the clauses 18-20, wherein at least one ohmic heating fiber is electrically insulated.

[0060] 22. Heatable decorative panel system according to any of the clauses 18-21 , wherein said conductive ohmic heating fibers form a resistive heating mesh.

[0061] 23. Heatable decorative panel system according to any of the clauses 18-22, wherein the mutually separated electrical contact pads are at least partially, preferably entirely formed by the ohmic heating fibers.

[0062] 24. Heatable decorative panel system according to any of the preceding clauses, wherein the heating structure of at least one decorative panel is at least partially covered by, and / or comprises, a coating, preferably an electrically insulating coating. 25. Heatable decorative panel system according to clause 24, wherein the coating, in particular the insulating coating, comprises at least one polymer material, in particular polyurethane.

[0063] 26. Heatable decorative panel system according to clause 24 or 25, wherein the coating, in particular the insulating coating, is at least partially formed by a varnish and / or lacquer.

[0064] 27. Heatable decorative panel system according to any of clauses 24-26, wherein a thickness of the coating, in particular the insulating coating, is situated between 10 and 50 micron, in particular about 20 micron.

[0065] 28. Heatable decorative panel system according any of the preceding clauses, wherein the heating structure covers at least a portion at least one contact pad, preferably at least 75%, more preferably at least 85% of at least one contact pad.

[0066] 29. Heatable decorative panel system according any of the preceding clauses, wherein a thickness of the heating structure is situated between 10 micron and 100 micron, preferably between 25 micron and 75 micron, more preferably about 50 micron.

[0067] 30. Heatable decorative panel system according any of the preceding clauses, wherein the heating structure is a printed heating structure, in particular a digitally printed heating structure.

[0068] 31 . Heatable decorative panel system according any of the preceding clauses, wherein graphene, and / or graphite and / or carbon particles are dispersed in the heating structure.

[0069] 32. Heatable decorative panel system according to any of the preceding clauses, wherein the heating structure is provided essentially only on a bottom surface of the core layer. 33. Heatable decorative panel system according any of the preceding clauses, wherein at least one connecting element comprises a first adhesive portion and a second self-adhesive portion, wherein said first and second self-adhesive portion are each connectable to a contact pad.

[0070] 34. Heatable decorative panel system according to any of the preceding clauses, wherein at least one connecting element is formed by an electrically conductive self-adhesive strip.

[0071] 35. Heatable decorative panel system according to any of the preceding clauses, wherein at least one connecting element is at least partially formed by an electric wire, wherein at least a portion of said wire is electrically insulated, and a first and / or second end of said wire is uninsulated.

[0072] 36. Heatable decorative panel system according to clause 35, wherein said uninsulated first and / or second end portion is connected or connectable to at least one contact pad of adjacent panels, for mutually electrically connecting the contact pads of adjacent panels and / or wherein at least one uninsulated portion is provided with a clamp.

[0073] 37. Heatable decorative panel system according clause 35 or 36, wherein the electric wire is connected to contact pads by means of self-adhesive conductive tape.

[0074] 38. Heatable decorative panel system according to any of the preceding clauses, wherein the connecting element is provided, preferably entirely provided, onto a bottom side of the panel.

[0075] 39. Heatable decorative panel system according to any of the preceding clauses, wherein at least one connecting element is connected, directly or indirectly, to a portion of at least one contact pad which is free of heating structure.

[0076] 40. Heatable decorative panel system according to any of the preceding clauses, wherein at least one connecting element, at least in a condition coupled to a contact pad, is bendable, particularly between 0 degrees and 180 degrees, more particularly about 90 degrees.

[0077] 41 . Heatable decorative panel system according to any of the preceding clauses, wherein a first and / or second panel side edge, preferably each panel side edge, of at least one panel are essentially free of heating structure and / or connecting element.

[0078] 42. Heatable decorative panel system according any of the preceding clauses, wherein the heating structure is formed by a heating paper and / or heating foil.

[0079] 43. Heatable decorative panel system according to any of the preceding clauses, wherein a bottom side of at least one panel, in particular a bottom surface of the core layer, is provided with one or more spacers.

[0080] 44. Heatable decorative panel system according to clause 43, wherein at least one spacer is at least partially formed by recesses and / or protrusions on or in a bottom side of said panel, in particular a bottom surface of the core layer.

[0081] 45. Heatable decorative panel system according to one of clauses 43 or 44, wherein at least one spacer, and optionally at least one recess and / or protrusion, is applied on or in a bottom surface of the core layer, and wherein at least a portion of the heating structure at least partially follows the relief structure of the bottom side of the panel, in particular the bottom surface of the core layer.

[0082] 46. Heatable decorative panel system according to any of the preceding clauses, wherein at least one panel comprises a backing layer, said backing layer applied at a side of the heating structure facing away from the core layer.

[0083] 47. Heatable decorative panel system according to clause 46, wherein one or more spacers and / or recesses and / or protrusions are provided in said backing layer, preferably wherein at least a portion of the heating structure at least partially follows the relief structure of the bottom side of the panel, in particular the backing layer. 48. Heatable decorative panel system according to any of clauses 43-47, wherein at least one spacer and / or recess is at least partially formed by a cavity and / or groove and / or air pocket, preferably formed at a side of the heating structure facing away from the core layer.

[0084] 49. Heatable decorative panel system according to any of the preceding clauses, wherein at least two contact pads are provided with a power connection, for connecting of a power supply to said contact pads via the power connections.

[0085] 50. Heatable decorative panel system according to clause 49, wherein a plurality of panels are mutually connected in series, preferably via one or more connecting elements, and wherein a plurality of panels are mutually connected in parallel, preferably via one or more power connections.

[0086] 51 . Heatable decorative panel system according to any of the preceding clauses, further comprising at least one power transformer for transforming of a supply voltage from 110 - 120V or 220 - 240V to a use voltage of 48V or 24V.

[0087] 52. Heatable decorative panel system according to any of the preceding clauses, wherein at least one contact pad has a width between about 25mm and 100m, preferably about 50mm.

[0088] 53. Heatable decorative panel system according to any of the preceding clauses, wherein at least one pair contact pads of at least one decorative panel are spaced apart about 180 mm to 1200 mm, preferably about 600mm to 1000mm, in particular about 820mm.

[0089] 54. Heatable decorative panel system according to any of the preceding clauses, wherein the core is at least partially composed of electrically insulating material.

[0090] 55. Heatable decorative panel system according to any of the preceding clauses, wherein the decorative top structure comprises: o at least one, preferably digitally printed, decorative layer forming at least one decor image, and o at least one transparent and / or translucent protective layer covering said decorative layer.

[0091] 56. Heatable decorative panel system according to any of the preceding clauses, wherein the heating structure comprises, or is substantially entirely formed of, material having a positive temperature coefficient.

[0092] 57. Heatable decorative panel covering, in particular a wall panel covering, consisting of mutually coupled heatable panels of the heatable decorative panel system according to any of the preceding clauses, in particular wherein contact pads of two adjacent panels are connected via at least one connecting element.

[0093] 58. Heatable decorative panel covering according to clause 57, wherein the covering has a surface area of about 1 m2 to 10m2, in particular about 5m2, and wherein, at least during use, a power consumption of the is about 0.5kW / hr.

[0094] 59. Kit of parts, comprising: a plurality of heatable decorative panels according to any of the clauses 1 -

[0095] 58, one or more connecting elements according to any of the clauses 1-58, and optionally, at least one power supply preferably comprising a power transformer.

[0096] 60. Method for installing a heatable decorative panel system according to one of clauses 1-58, comprising the steps of: a) providing at least one first decorative panel on a supporting surface, in particular a wall, b) providing at least one second decorative panel, c) connecting at least one first end portion of a connecting element to at least one contact pad of said panel, d) connecting at least one second end portion of the connecting element to at least one contact pad of a different panel, e) coupling the first and second panel, in particular via the first and second coupling profiles thereof f) optionally, connecting at least one power supply to the contact pads. 61 . Decorative panel for use in a panel system according to any of clauses 1- 58.

[0097] The present invention will hereinafter be further elucidated based on the following non-limitative figures, wherein:

[0098] - Figure 1 shows a bottom side of a decorative panel;

[0099] - Figure 2 shows a cross section of a first embodiment of a decorative panel along line A-A’ shown in Fig. 1 ;

[0100] - Figure 3 shows a cross section of a second embodiment of a decorative panel along line A-A’ shown in Fig. 1 ;

[0101] - Figure 4 shows a non-limitative embodiment of a heatable decorative panel system;

[0102] - Figure 5 shows a wall covering according to an embodiment of the present invention; and

[0103] - Figures 6a and 6b show different embodiments of a detail of the present invention.

[0104] Figure 1 shows a bottom view of a decorative panel 100 according to the invention. The decorative panel 100 comprises a first and second side edge 107, 108, and a second and third side edge 117, 118. On the bottom side also a plurality of contact pads 105 are shown. Although this figure shows four contact pads 105, these portions are the ones exposed to the surrounding. In reality a majority of these pads 105 are covered by the heating structure as can be shown in more detail with respect to figures 2 and 3. Hence, the four contact pads 105 shown in this figure are in fact exposed portions of two contact tracks 105 of which a portion is covered by the heating structure. Figures 2 and 3, as discussed hereinafter, each describe different embodiments of the present invention and show a cross section of a panel 100 along the line A-A’ as shown in figure 1 .

[0105] Figure 2 shows a cross-section of a first non-limitative embodiment of the decorative panel 100. The decorative panel 100 comprises a core layer 101 , on a top surface 103 of said core layer 101 a decorative top structure 102 is provided. In this figure the decorative top structure 102 is shown as a single layer. However, it is conceivable that said decorative top structure comprises a plurality of layers, such as but not limited to: a decor later, a pattern layer, and a wear layer. It is also conceivable that said decorative top structure 102 is at least partially formed in the core layer 101. The first and second panel side edge 107, 108 are shown, and are provided with a first and second coupling profile 111 , 110 respectively. The first and second coupling profile 111 , 110 are shown as a tongue groove style coupling profile, but it is conceivable that different types of coupling profiles are used for coupling of adjacent panels 100. Onto a bottom surface 104 of the core layer 101 two contact pads 105 are provided. Said contact pads 105 are arranged mutually spaced apart, and in this embodiment near the panel side edges 107, 108. It is imaginable that said contact pads 105 extend along a substantial portion of said panel side edges 107, 108. Said bottom surface 104 of the core layer 101 is at least partially covered by an ohmic heating structure 119. At least in this cross sectional view the contact pads 105, in the form of the tracks 105, are also covered by the heating structure 119. Said heating structure 119 may be in the form of a printed layer and have resistive and conductive properties such as to allow generation of heat when the contact pads 105 are connected to a power source. Therefore, it is needed for the heating structure 119 to make, at least electrical, contact with the contact pads. Although this embodiment sows the heating structure 119 being disposed onto the contact pads, it is also imaginable, although maybe not preferred, that the contact pads 105 are provided onto the heating structure 119. The heating layer 119 in this embodiment does not cover the entire surface area of the contact pads 105 since this allows to make electrical contact with said pads 105 without the need to locally remove material. Here, the heating structure 119 is formed by one layer 119. Covering a substantial portion of the heating structure 119 is an optional coating or layer 106. Said layer 106 in this embodiment formed by a PU varnish. This varnish electrically insulates the heating structure 119 situated below. It was surprisingly found that this provides an improved heating efficiency of a panel 100 according to the invention. As can be seen in the figure, the heating structure covers only the bottom side of the panel 100. Also, the contact pads 105 are entirely situated on the bottom side of the panel 100, in this embodiment on the bottom surface 104 of the core layer 101 . Also, the exposed portions 105 as shown in figure 1 are on the bottom side, which makes it possible to connect adjacent contact pads 105 of adjacent panels exclusively from the bottom side. Hence, not compromising the functioning of the coupling profiles 110, 111. Also, this makes the electrical system less prone to potential electrical shortage when a fluid is spilled onto the top side of the panel as the electrical system (105, 119) is further removed from said exposed top side of the panel.

[0106] Figure 3 shows a panel 100 according to a different embodiment as the one showed in figure 2 along the same cross-section A-A’ as shown in figure 1. The embodiment mainly differs in the bottom side of the panel 100, as the top surface 103 of the core layer 101 is also provided with a decorative top structure 102. However, the bottom surface 104a, 104b comprises different height levels. In a bottom surface 103 of the core layer 101 a plurality of recesses 109 are provided, for example by means of calendaring or milling. Here, the recesses form the spacers according to the invention. As an alternative to the recesses 109 as shown in this figure it is also conceivable that protrusions are provided. Due to these recesses, or spacers in general, the bottom side of the panel 100 comprises different height levels 104a and 104b. Due to said difference in height 104a, 104b the panel 100 encloses air portions between a substrate and the bottom side of the panel 100, which form insulating spaces which may increase the efficiency of the panels 100 heating capacity. The figure also indicates the presence of the contact pads 105 which are arranged along the edges 107, 108 of the panel 100. Onto said bottom side of the panel a heating structure 119 in the form of a continuous layer. The layer 119 follows the relief in the bottom side of the panel 100 formed by the recesses 109. Due to the heating structure 119 following the relief formed by recesses 109 the heating structure 119 has a larger surface area. Therefore, this may allow the heating structure 119 to have a larger heat emission. In this embodiment, the optional coating or cover layer 106 as shown in figure 2 is not provided. However, it is conceivable that said coating or cover layer is similarly provided onto the heating structure 119 according to this figure.

[0107] Figure 4 shows a schematic representation of the heatable decorative panel system 200 according to the invention. Here, a total of three panels 100 are depicted, seen from a bottom side thereof. However, it is clear that the number of panels 100 is arbitrary and not limitative. Each panel 100 as shown in this embodiment comprises two tracks 105 forming the contact pads 105. In this respect it should be noted that the contact pads 105 may be formed otherwise, and for illustrative purposes the heating structure 119 is not depicted. This figure clearly illustrates how adjacent panels 100 may be mutually electrically connected. Adjacent contact pads 105 are mutually connected by means of a connecting element 201. The connecting element 201 may be a self-adhesive conductive strip, such that an easy connection between contact pads 105 of adjacent panels 100 may be established. In figures 6a and 6b more details regarding the connecting element 201 are depicted and discussed. This figure indicates that a power connection 206 is connected to the leftmost and rightmost contact pad 105 of the system 200. These power connections 206 are connected, via two connections 202, 203, to a power transformer 204. The power transformer 204 may allow to transform a grid power of 230V, coming from a grid connection 205, into a safer power of about 24V or 48V. Hence the grid connection 205 supplies power at a voltage level of about 230V towards the power transformer 204, which transforms it to a power at a voltage level of about 24V or 48V, and supplies said lower voltage power to the power connections 206 via the connecting cables 202, 203.

[0108] Figure 5 depicts a heatable decorative wall covering 300. Although this figure shows a wall, it is also imaginable that the system is placed on a floor. The wall covering 300 is placed on a wall 303, particularly stretching around a corner 304 without the need to interrupt the heating system. This may be achieved by means of the bendable connecting elements 301 , 302 which are used in this particular embodiment. In this figure, the contact pads 105 of the panels 100 are not visualized for illustrative purposes, however it is clear that the connecting elements 301 , 302 connect to contact pads 105 of adjacent panels 100 as discussed. Two decorative panels 100 are provided at a first side of the corner 304 and two panels 100 on the other side of the corner 304. However, the number of panels 100 at each side of the corner 304 may be adapted. The panels 100 at the same side of the corner 304 may be connected via the connecting element 301 , which is not folded but only connects the adjacent panels 100. However, the panels 100 adjacent to the corner 304 are connected by a bended or folded connecting element 302. This is particularly beneficial as it also allows to provide for a continuous wall covering 300 which heating structure is not interrupted due to the corner 304. This may for example be achieved by a connecting element 302 formed out of a conductive strip of self-adhesive material, such as a self-adhesive aluminium and / or copper. The connecting element 302 does not necessarily have to be entirely self-adhesive. Two patches which are self-adhesive may be sufficient for allowing said patches to connect to the contact pads 105 of adjacent panels. Figures 6a and 6b show two alternative embodiments for connecting elements for use in a system according to the invention. Both solutions as shown in these figures may be applied in any of the previously shown embodiments. Figure 6a shows a first embodiment, here two adjacent panels 100 each have an exposed contact pad 105. Although only a small contact pad 105 is shown, the contact pad 105 may be larger, or covered by a heating structure as discussed before. Nevertheless, onto the contact pad 105, at least the exposed portion thereof, a connecting element 123 is provided. The connecting element 123 shown in this figure is formed by three parts of mutually connected strips of conductive self- adhesive material 112, 121 , 122. The three strips overlap and mutually connect at the portions 120 to establish a mutual electrical connection. The first and third piece 121 , 122 are each connected to a contact pad 105. The second, intermediate, piece 112 may be connected to the bottom side of the panel 100 or may be loose with respect to the bottom side of the panel 100. It is preferred that said connecting element 123 is only adhered to the panel 100 at the exposed area of the contact pads 105, such that the remaining portion of the connecting element 123 may provide for some degree of movement of adjacent panels. It is possible that two portions are pre-attached to a first panel 100, and the third portion is pre-attached to a second panel 100. During installation of the system, the three portions may be mutually connected for electrically connect said contact pads 105. Although the embodiment described in this figure shows the connecting element 123 is composed of three portions 112, 121 , 122, it is also imaginable that these three portions are mutually integrated, and hence form a single connecting element, out of a single portion. In such an instance, the overlapping portions 120 may not be present.

[0109] Figure 6b shows an alternative embodiment. The contact pads 105 as presented on the panels 100 is kept the same as described in figure 6a, only the connecting element 123 is formed differently. Here, the connecting element is formed out of two mutually connectable wires 124. Each wire 124 comprises two ends. A first end of each wire 124 is formed by mutually separated electrical wires 115. These wires are partially spread out over the contact pad 105 and connected to the contact pad 104 via a self-adhesive conductive strip 114, such as an aluminium strip 114. Said aluminium strip adheres the first end of the cable 124 to the contact pad 105 such as to establish an electrical connection between the wire 124 and contact pad 105. Although here it is shown that the cable comprises a series of parallel cables 115, it is also conceivable that this manner of fixating the wire 124 to the contact pad 105 is used when only a single cable is present. The second end of the wire 124 is provided with a clamp 116. These clamps may, for example during installation, be mutually connected to establish a connection between adjacent contact pads 105. In a slightly different embodiment, the clamps 116 are not provided for and a single wire 124 is directly connected to the contact pads 105 in the way as explained with respect to the first end. Hence, a connection between contact pads 105 may be established via a single wire 124, without applying a clamp 116.

[0110] The above-described inventive concepts are illustrated by several illustrative embodiments. It is conceivable that individual inventive concepts may be applied without, in so doing, also applying other details of the described example. It is not necessary to elaborate on examples of all conceivable combinations of the abovedescribed inventive concepts, as a person skilled in the art will understand numerous inventive concepts can be (re)combined in order to arrive at a specific application.

[0111] It will be apparent that the invention is not limited to the working examples shown and described herein, but that numerous variants are possible within the scope of the attached claims that will be obvious to a person skilled in the art.

[0112] The verb “comprise” and conjugations thereof used in this patent publication are understood to mean not only “comprise”, but are also understood to mean the phrases “contain”, “substantially consist of”, “formed by” and conjugations thereof.

Claims

Claims1 . Heatable decorative panel system, in particular a heatable decorative wall panel system, a heatable decorative ceiling panel system, a heatable floor panel system, or a heatable decorative furniture panel system, comprising:- a plurality of decorative panels, wherein the panels, preferably each panel, comprise: o a core layer having a top surface and a bottom surface, o a decorative top structure affixed, directly or indirectly, onto said top surface of the core layer, o at least one ohmic heating structure affixed, directly or indirectly, onto said bottom surface of the core layer, o at least two mutually separated electrical contact pads, connected or connectable to said heating structure, wherein said contact pads are entirely positioned at a side of the core layer and / or at a side of the heating structure facing away from the top surface of the core layer, o at least one first panel edge having a first coupling profile, and at least one second panel edge having a second coupling profile, wherein the first and second coupling profile are configured to coact such that two panels can be coupled at the first and second edges,- at least one connecting element, for at least electrically connecting contact pads of at least one panel, preferably adjacent panels in a coupled condition, wherein said at least one connecting element is entirely positioned at a side of the core layer and / or at a side of the heating structure facing away from the top surface of the core layer.

2. Heatable decorative panel system according to claim 1 , wherein at least one contact pad, preferably the at least two contact pads, form a track, in particular an elongated track.

3. Heatable decorative panel system according to claim 1 or 2, wherein at least a portion of the heating structure, preferably the entire heating structure, and the contact pads are integrally formed.

4. Heatable decorative panel system according to any of the preceding claims, wherein at least one contact pad, preferably each contact pad, stretches along at least a portion of at least one panel edge of at least one decorative panel, preferably at least one of the first and / or second panel edge.

5. Heatable decorative panel system according to any of the preceding claims, wherein the two contact pads are arranged at opposing panel edges of at least one decorative panel.

6. Heatable decorative panel system according to any of the preceding claims, wherein at least one contact pad, in particular each contact pad, is a printed contact pad.

7. Heatable decorative panel system according to any of the preceding claims, wherein at least a portion of the at least one contact pad is formed by a conductive strip, in particular a self-adhesive conductive strip.

8. Heatable decorative panel system according to claim 7, wherein the conductive strip, in particular the self-adhesive conductive strip, is an aluminium and / or copper strip.

9. Heatable decorative panel system according to claim 7 or 8, wherein a thickness of the conductive strip, in particular the self-adhesive conductive strip, is situated between about 0.01 mm and about 0.2 mm, preferably between about 0.025 mm and about 0.12 mm.

10. Heatable decorative panel system according to any of the preceding claims, wherein the heating structure of at least one decorative panel is at least partially formed by at least one layer.11 . Heatable decorative panel system according to claim 10, wherein at least one layer is a resistive heating layer, preferably a printed resistive heating layer.

12. Heatable decorative panel system according to any of the preceding claims, wherein the ohmic heating structure of at least one decorative panel is atleast partially defined by and / or comprises at least one ohmic heating network and / or ohmic heating pattern.

13. Heatable decorative panel system according to claim 12, wherein the ohmic heating network and / or ohmic heating pattern comprises a plurality of mutually spaced apart ohmic heating traces, wherein each ohmic heating trace extends between the at least two mutually separated electrical contact pads.

14. Heatable decorative panel system according to claim 13, wherein at least two, preferably all spaced apart ohmic heating traces are mutually parallel.

15. Heatable decorative panel system according to claim 13 or 14, wherein at least one pair of adjacent spaced apart ohmic heating traces, preferably all pairs of adjacent spaced apart ohmic heating traces, are connected via at least one ohmic heating bridge element, preferably a plurality of spaced apart ohmic heating bridge elements.

16. Heatable decorative panel system according to claim 15, wherein at least two ohmic heating bridge elements are spaced apart by approximately 3mm to 45mm, preferably 15mm to 45mm, more preferably 30mm.

17. Heatable decorative panel system according to any of the claims 13-15, wherein at least one ohmic heating trace has a width of approximately 30mm, and wherein at least two adjacent, preferably all adjacent ohmic heating traces are spaced apart by approximately 3mm to 45mm, preferably 15mm to 45mm, more preferably 30mm.

18. Heatable decorative panel system according to any of the preceding claims, wherein the ohmic heating structure is at least partially formed by and / or comprises ohmic heating fibers.

19. Heatable decorative panel system according to claim 18, wherein said ohmic heating fibers are stitched into the core layer and / or a into a carrier layer of the ohmic heating structure.

20. Heatable decorative panel system according claim 18 or 19, wherein said ohmic heating fibers have a diameter or thickness of approximately 0.1 mm up to 1 .0 mm, preferably up to 0.8 mm.21 . Heatable decorative panel system according any of the claims 18-20, wherein at least one ohmic heating fiber is electrically insulated.

22. Heatable decorative panel system according to any of the claims 18-21 , wherein said conductive ohmic heating fibers form a resistive heating mesh.

23. Heatable decorative panel system according to any of the claims 18-22, wherein the mutually separated electrical contact pads are at least partially, preferably entirely formed by the ohmic heating fibers.

24. Heatable decorative panel system according to any of the preceding claims, wherein the heating structure of at least one decorative panel is at least partially covered by, and / or comprises, a coating, preferably an electrically insulating coating.

25. Heatable decorative panel system according to claim 24, wherein the coating, in particular the insulating coating, comprises at least one polymer material, in particular polyurethane.

26. Heatable decorative panel system according to claim 24 or 25, wherein the coating, in particular the insulating coating, is at least partially formed by a varnish and / or lacquer.

27. Heatable decorative panel system according to any of claims 24-26, wherein a thickness of the coating, in particular the insulating coating, is situated between 10 and 50 micron, in particular about 20 micron.

28. Heatable decorative panel system according any of the preceding claims, wherein the heating structure covers at least a portion at least one contact pad, preferably at least 75%, more preferably at least 85% of at least one contact pad.

29. Heatable decorative panel system according any of the preceding claims, wherein a thickness of the heating structure is situated between 10 micron and 100 micron, preferably between 25 micron and 75 micron, more preferably about 50 micron.

30. Heatable decorative panel system according any of the preceding claims, wherein the heating structure is a printed heating structure, in particular a digitally printed heating structure.

31. Heatable decorative panel system according any of the preceding claims, wherein graphite, and / or graphene, and / or carbon particles are dispersed in the heating structure.

32. Heatable decorative panel system according to any of the preceding claims, wherein the heating structure is provided essentially only on a bottom surface of the core layer.

33. Heatable decorative panel system according any of the preceding claims, wherein at least one connecting element comprises a first adhesive portion and a second self-adhesive portion, wherein said first and second self- adhesive portion are each connectable to a contact pad.

34. Heatable decorative panel system according to any of the preceding claims, wherein at least one connecting element is formed by an electrically conductive self-adhesive strip.

35. Heatable decorative panel system according to any of the preceding claims, wherein at least one connecting element is at least partially formed by an electric wire, wherein at least a portion of said wire is electrically insulated, and a first and / or second end of said wire is uninsulated.

36. Heatable decorative panel system according to claim 35, wherein said uninsulated first and / or second end portion is connected or connectable to at least one contact pad of adjacent panels, for mutually electrically connecting the contact pads of adjacent panels and / or wherein at least one uninsulated portion is provided with a clamp.

37. Heatable decorative panel system according claim 35 or 36, wherein the electric wire is connected to contact pads by means of self-adhesive conductive tape.

38. Heatable decorative panel system according to any of the preceding claims, wherein the connecting element is provided, preferably entirely provided, onto a bottom side of the panel.

39. Heatable decorative panel system according to any of the preceding claims, wherein at least one connecting element is connected, directly or indirectly, to a portion of at least one contact pad which is free of heating structure.

40. Heatable decorative panel system according to any of the preceding claims, wherein at least one connecting element, at least in a condition coupled to a contact pad, is bendable, particularly between 0 degrees and 180 degrees, more particularly about 90 degrees.

41. Heatable decorative panel system according to any of the preceding claims, wherein a first and / or second panel side edge, preferably each panel side edge, of at least one panel are essentially free of heating structure and / or connecting element.

42. Heatable decorative panel system according any of the preceding claims, wherein the heating structure is formed by a heating paper and / or heating foil.

43. Heatable decorative panel system according to any of the preceding claims, wherein a bottom side of at least one panel, in particular a bottom surface of the core layer, is provided with one or more spacers.

44. Heatable decorative panel system according to claim 43, wherein at least one spacer is at least partially formed by recesses and / or protrusions on or in a bottom side of said panel, in particular a bottom surface of the core layer.

45. Heatable decorative panel system according to one of claims 43 or 44, wherein at least one spacer, and optionally at least one recess and / orprotrusion, is applied on or in a bottom surface of the core layer, and wherein at least a portion of the heating structure at least partially follows the relief structure of the bottom side of the panel, in particular the bottom surface of the core layer.

46. Heatable decorative panel system according to any of the preceding claims, wherein at least one panel comprises a backing layer, said backing layer applied at a side of the heating structure facing away from the core layer.

47. Heatable decorative panel system according to claim 46, wherein one or more spacers and / or recesses and / or protrusions are provided in said backing layer, preferably wherein at least a portion of the heating structure at least partially follows the relief structure of the bottom side of the panel, in particular the backing layer.

48. Heatable decorative panel system according to any of claims 43-47, wherein at least one spacer and / or recess is at least partially formed by a cavity and / or groove and / or air pocket, preferably formed at a side of the heating structure facing away from the core layer.

49. Heatable decorative panel system according to any of the preceding claims, wherein at least two contact pads are provided with a power connection, for connecting of a power supply to said contact pads via the power connections.

50. Heatable decorative panel system according to claim 49, wherein a plurality of panels are mutually connected in series, preferably via one or more connecting elements, and wherein a plurality of panels are mutually connected in parallel, preferably via one or more power connections.51 . Heatable decorative panel system according to any of the preceding claims, further comprising at least one power transformer for transforming of a supply voltage from 110 - 120V or 220 - 240V to a use voltage of 48V or 24V.

52. Heatable decorative panel system according to any of the preceding claims, wherein at least one contact pad has a width between about 25mm and 100m, preferably about 50mm.

53. Heatable decorative panel system according to any of the preceding claims, wherein at least one pair contact pads of at least one decorative panel are spaced apart about 180 mm to 1200 mm, preferably about 600mm to 1000mm, in particular about 820mm.

54. Heatable decorative panel system according to any of the preceding claims, wherein the core is at least partially composed of electrically insulating material.

55. Heatable decorative panel system according to any of the preceding claims, wherein the decorative top structure comprises: o at least one, preferably digitally printed, decorative layer forming at least one decor image, and o at least one transparent and / or translucent protective layer covering said decorative layer.

56. Heatable decorative panel system according to any of the preceding claims, wherein the heating structure comprises, or is substantially entirely formed of, material having a positive temperature coefficient.

57. Heatable decorative panel covering, in particular a wall panel covering, consisting of mutually coupled heatable panels of the heatable decorative panel system according to any of the preceding claims, in particular wherein contact pads of two adjacent panels are connected via at least one connecting element.

58. Heatable decorative panel covering according to claim 57, wherein the covering has a surface area of about 1 m2 to 10m2, in particular about 5m2, and wherein, at least during use, a power consumption of the is about 0.5kW / hr.

59. Kit of parts, comprising:a plurality of heatable decorative panels according to any of the claims 1-58, one or more connecting elements according to any of the claims 1 -58, and optionally, at least one power supply preferably comprising a power transformer.

60. Method for installing a heatable decorative panel system according to one of claims 1 -58, comprising the steps of: a) providing at least one first decorative panel on a supporting surface, in particular a wall, b) providing at least one second decorative panel, c) connecting at least one first end portion of a connecting element to at least one contact pad of said panel, d) connecting at least one second end portion of the connecting element to at least one contact pad of a different panel, e) coupling the first and second panel, in particular via the first and second coupling profiles thereof f) optionally, connecting at least one power supply to the contact pads.61 . Decorative panel for use in a panel system according to any of claims 1 -58.

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