Decorative panel

Abstract

The invention relates to a panel, in particular a floor, wall, ceiling or building panel, comprising at least one core layer; at least one top layer, in particular at least one decorative top layer; and at least one buffer layer between the at least one core layer and the at least one top layer wherein the at least one buffer layer comprises at least one pore structure, in particular at least one porous structure; wherein the at least one top layer has an elastic modulus of at least 1800 Mpa according to the EN 310 standard, and / or the at least one top layer has flexibility around a mandrel having a diameter of 50 mm or greater, as tested according to the ASTM F137 standard.

Description

Technical Field

[0001] The invention relates to a panel, in particular a floor, wall, ceiling or building panel. The invention also relates to a floor covering comprising said panel. Background Art

[0002] Fall prevention and floor compliance are important topics when considering building materials, especially materials such as decorative flooring, especially when used in situations where it is conceivable that users or residents may be exposed to falls that are expected to occur. Common environments where fall prevention and compliance are relevant are sports stadiums, but also residential homes, especially those for the elderly, disabled or young children. The consequences of a fall can be serious, such as resulting in a hip fracture or head injury, or other physical, psychological and / or social consequences. This leads directly to medical costs and an increased risk of early death. According to an analysis by the United Nations, 30 million people will turn 60 every year, and the total number of people over 60 is expected to reach 3 billion by 2100. This group of people urgently needs flooring that meets their special needs, especially floors that are safe and comfortable, without compromising on aesthetics and the performance of state-of-the-art flooring. Often, the design of welfare facilities includes handrails while eliminating steps to achieve a barrier-free environment. In addition, there are various known solutions to reduce the risk of injury caused by falls. It is well known that devices such as pads worn on specific parts of the body (such as the buttocks) can absorb the impact or shock of a fall and reduce the risk of fractures. However, this device only protects the covered parts of the body. Other uncovered body parts, such as the wrists, will not be protected in the event of a fall.

[0003] As a solution, impact absorbing systems have been proposed with the goal of preventing injuries by reducing the impact of falls. Known impact absorbing systems include flexible flooring, rubber flooring and sports floor coverings, which are flexible and are typically made of rubber or flexible homogeneous vinyl materials. It is known to install these types of flooring in combination with closed-cell foam, vulcanized rubber sheets or an array of deformable elastomeric cells under an elastomeric and / or flexible surface layer to provide a shock absorbing structure. However, the combination of an elastic and / or flexible surface layer with a deformable material such as foam often produces a dangerous point impact surface deformation that does not adequately prevent injuries from severe impact or "bottoming out" impacts. As a result, the structure containing the foam layer may deform or even displace in response to axial impact forces (such as impacts to the hip, elbow or head, or even just standing for a long time). The foam layer may be over-compressed at a certain point, transmitting most of the impact force directly to the subfloor, which is generally not designed to absorb impact and may therefore not provide the necessary cushioning required to protect individuals from injury. These factors may be even more concerning in nursing homes and welfare institutions, where many residents may have an unsteady gait or require the use of wheelchairs.

[0004] In addition to the above disadvantages, most impact-absorbing systems, especially rubber flooring and sports floor coverings, are heavy, difficult to install, and require a professional to install. Installing such flooring in large spaces takes a lot of time, and it can be cumbersome to install such flooring in smaller spaces because the materials used in them are difficult to work with. In some cases, the surface of such flooring may not be completely seamless and may contain grooves or other imperfections. Finally, due to their size, such systems are not aesthetically pleasing.

[0005] In view of the above limitations of conventional systems, there is a need for a hard floor covering that is easy to install, remains relatively rigid or structurally stable under normal use conditions, thereby allowing the use of wheelchairs, etc., without interfering with normal use, does not exhibit point-like deformation, but rather deforms elastically in areas, has strong compliance, and is able to cushion the body and absorb a large amount of impact force in the event of a fall. Summary of the invention

[0006] The invention provides a panel, in particular a decorative panel, especially a floor, wall, ceiling or building panel, comprising:

[0007] - at least one core layer;

[0008] - at least one top layer, in particular at least one decorative top layer; and

[0009] - at least one buffer layer located between said at least one core layer and said at least one top layer;

[0010] wherein the at least one buffer layer comprises at least one pore structure, in particular at least one porous structure, and

[0011] wherein the modulus of elasticity of at least one of the top layers is at least 1800 MPa according to EN 310 and / or wherein the at least one top layer is flexible around a mandrel having a diameter of 50 to 350 mm when tested according to ASTM F137 or wherein the at least one top layer has a flexibility of 50 to 350 mm in a mandrel test according to ASTM F137.

[0012] The panel of the present invention has a good balanced combination of rigidity and compliance. According to the present invention, due to the combination of the semi-rigid top layer and the buffer layer, the panel can absorb impact forces to a certain extent, especially when used as a floor. When hit by a falling individual or object, the kinetic energy transmitted to the panel is initially distributed in a certain area of ​​the top layer and then transferred to the buffer layer, where the kinetic energy is converted into internal energy in the structure of the buffer layer. In this way, the kinetic energy when impacting the panel is partially dissipated from the surface and the entire volume of the semi-rigid top layer before being transferred to at least one buffer layer. Subsequently, when the kinetic energy is transferred to at least one buffer layer, its structure is rearranged or compressed, further redistributing the impact force to the entire structure, while absorbing a large amount of kinetic energy within the structure, so that the kinetic energy recovered during the impact is significantly reduced. Therefore, the energy recovery capacity of the panel is significantly improved by the combination of the top layer and the buffer layer. Therefore, the individual / object that falls during the impact is protected from injury or damage, while protecting the panel from permanent deformation. In addition, because the buffer layer is compressible / foldable, when the impact force is applied to at least one semi-rigid top layer, its time response during the impact allows the at least one semi-rigid top layer to deform to a certain extent. Unlike conventional impact absorption solutions (such as point-elastic surfaces) where the kinetic energy generated by the faller's impact is absorbed only at the point of impact and dissipated within a short period of time, the panel of the present invention includes a layered impact absorption system that effectively disperses the kinetic energy over a larger surface rather than concentrating it at one point. In addition, the layered impact absorption system of the present invention dissipates the impact energy over a longer period of time, thereby ensuring optimal energy absorption. More specifically, the layered impact absorption system includes a semi-rigid top layer and at least one buffer layer, which synergistically enhance each other's functions to absorb and mitigate impact forces. The semi-rigid top layer effectively transfers energy from the point of impact to a wider area of ​​the panel, more specifically at least one buffer layer. The semi-rigid top layer prevents the force from being concentrated at one point and spreads such force / energy throughout the panel of the present invention. Then, at least one buffer layer acts to compress / deform, thereby dispersing the energy generated by the impact and significantly reducing the local pressure applied to any specific body part during impact. According to the present invention, this synergistic function of combining at least one buffer layer with the top layer is called volume compression. This functionality of the at least one cushioning layer reduces peak forces and gradually decelerates the individual's body upon impact, thereby increasing energy dissipation in the semi-rigid top layer and, in turn, reducing the risk of injury.

[0013] The combination of the top layer and the buffer layer of the present invention allows the top layer and the entire panel to act as a cushion to receive the force applied by the falling individual or object, while also allowing the floor panel to have sufficient rigidity to allow the interlocking mechanism to be placed arbitrarily thereon. The combination of the semi-rigid top layer and the buffer layer can also increase the compressive strength of the (floor) panel, thereby increasing its bending modulus and bending failure load, thereby effectively gradually reducing the impact force and impact energy to a minimum when in contact with the surface of the floor panel. Such a reduction reduces the risk of injury and provides better impact protection for individuals or objects that fall into contact with the floor formed by the panel according to the present invention. Due to the panel having a semi-rigid, preferably decorative top layer and at least one buffer layer, in particular a foldable, flexibly oriented and / or compressible buffer layer, the comfort of walking on the floor panel manufactured according to the present invention is further improved. Therefore, the panel according to the present invention can help individuals with physical disabilities, such as those suffering from diseases such as rheumatoid arthritis, to move around easily and / or relieve pain or restraint, while providing sufficient support to withstand point deformations such as chair legs, table legs, high heels, wheelchairs, etc.

[0014] The panel of the present invention includes at least one buffer layer. As used herein, the buffer layer provides at least one method of attenuating vibrations generated by axial impact forces, axial physical forces and / or sound waves or oscillations by compression, folding, compaction, absorption, decoupling or isolation or a combination thereof. In some embodiments, at least one buffer layer is at least partially comprised of a material that bends when subjected to an impact force or load force. The buffer layer may be referred to as a compression or compressible layer, a foldable layer, a compactable layer, a shock absorbing layer, a decoupling layer or a layer with a decoupling element, an isolation layer, a deformable layer, a buckling orientation or a constructed material or a combination thereof. If used as a floor panel, at least one buffer layer is used between at least one core layer and at least one top layer, and due to the compressible nature of the buffer layer, the stiffness of the ground under the panel can be reduced. At least one buffer layer generally provides the best flexibility, thereby greatly reducing the impact force when falling. In addition, it can reduce the amplitude of certain frequency sound waves passing through the floor, wall, ceiling or building panel, and absorb part of the sound wave energy. Another benefit of using at least one buffer layer is that it helps to adapt the panel to the irregularities of the underlying floor.

[0015] It is conceivable that at least one buffer layer is adhered to the upper surface of at least one core layer. For example, the at least one buffer layer can be adhered to the upper surface of at least one core layer by means of an adhesive and / or a glue. It is also conceivable that at least one buffer layer is adhered to the bottom surface of at least one (decorative) top layer. For example, the at least one buffer layer can be adhered to the bottom surface of at least one (decorative) top layer by means of an adhesive and / or a glue. It is also conceivable that at least one buffer layer serves as a core layer of the panel.

[0016] It is envisioned that at least one of the buffer layers has a threshold-activated constant force response characteristic, which includes an initial elastic deformation during a first time period, wherein the buffer layer can absorb at least some of the kinetic energy and displace without providing strong resistance, wherein the force can gradually increase with increasing displacement until a certain threshold and / or displacement threshold (in millimeters). It is envisioned that after exceeding a certain displacement threshold, at least one of the buffer layers may exhibit a harder response, transition to plastic deformation, and / or transition from elastic behavior to more inelastic behavior in a second stage. It is envisioned that in the second stage, the buffer layer resists further displacement with a relatively constant force, wherein the slope of the force-displacement curve is relatively flat, indicating that the stiffness does not increase rapidly, in fact reducing the suddenness of the impact force, and / or gradually reducing the impact force. It is envisioned that the displacement threshold or yield point is accompanied by the peak force or Fmax experienced during the impact. It is also envisioned and preferably that the yield point is lower than the peak force or Fmax experienced during the impact, and preferably, this can also be achieved in the third compaction stage. Presumably, this threshold-activated constant force response is advantageous in the case of the panel as a floor because it provides a more gradual deceleration during impact, reducing or at least delaying the peak force (Fmax = Max(F(displacement))) and maximum acceleration (Gmax = Max(a(time)), where a(time) = the acceleration of the person during the fall at a specific point in time or time period during the impact) experienced by the person falling. The response advantageously dissipates the kinetic energy of the impact over a longer distance and time, thereby reducing the risk of injury, while maintaining a sufficiently high threshold or yield point to support normal use of the floor, even in situations with high traffic. The threshold or yield point can be understood as the maximum force or weight per unit surface area that can be safely applied to such a floor in daily use, beyond which the floor surface transitions to a safety floor that is designed to flex and reduce the maximum acceleration applied to a falling person.

[0017] At least one buffer layer preferably includes at least one porous structure selected from the group consisting of a honeycomb structure, a double-wall structure, a corrugated structure, a foamed structure, a grid structure or a combination thereof. In one possible embodiment, at least one buffer layer includes at least one pore structure layer. It is conceivable that the pore structure layer is a porous structure comprising a plurality of pore structures, preferably having the same intended function as the buffer layer. In another preferred embodiment, at least one buffer layer includes at least one porous structure layer, and the porous structure layer is selected from the group consisting of open cells, closed cells, honeycomb structures, foamed layers, grid structures or a combination thereof. For example, the porous structure includes a 2.5-dimensional or planar constructed material or a 3-dimensional constructed material. The 2.5-dimensional or planar constructed material includes at least one two-dimensional shape, and a three-dimensional structure in a third direction is formed by thermoforming and / or extrusion. By having a 2.5-dimensional lattice configuration, the porous structure of the buffer layer can be formed by a plurality of folding points and a plurality of pore walls or pillars that are repeated at least once on at least one axis. For example, at least one buffer layer may include at least one porous structure, the at least one porous structure comprising a 2.5-dimensional constructed material, preferably a 2.5-dimensional continuous lattice configuration formed by n folding points or connection points and p pore walls repeated at least once on at least one axis. At least one 3-dimensional porous structure may also be formed by multiple nodes and multiple pore walls or pillars repeated at least once on at least two axes. It is also conceivable that at least one buffer layer includes at least one porous structure, the porous structure includes a 3-dimensional constructed material, preferably a 3-dimensional lattice configuration formed by n nodes and p pillars repeated at least once on at least 2 axes. The 2.5-dimensional constructed material and / or the 3-dimensional constructed material are selected from the group of hexagonal grid structures, origami structures, folding structures and / or five-mode metamaterials. It is also conceivable that at least a portion of the pillars and / or pore walls include at least one folding point or connection point, or may be multiple folding points or connection points. In some configurations, multiple pillars or pore walls include at least one folding point. At least one folding point may also be referred to as a node, joint or hinge.

[0018] In a preferred embodiment, at least some (preferably most) of the pillars and / or hole walls are substantially inclined, in particular the pillars and / or hole walls are at an angle of 30 to 60 degrees to the expected impact force direction, in order to avoid the structure or system to exhibit inertial effects and to allow the structure to exhibit strain rate sensitivity. By following this configuration, the impact force is dissipated in the structure in a preferred manner, thereby enhancing the safety performance of the panel. At least 20%, preferably at least 40%, more preferably at least 60% of the pillars and / or hole walls are inclined in the direction of the impact force and / or in a direction perpendicular to at least one upper surface of the panel.

[0019] At least one buffer layer may also include at least one pore structure, the pore structure comprising a spatially periodic array of cells having interconnected edges and faces and / or interconnected struts and nodes. Optionally, at least one buffer layer may include at least one pore structure, the pore structure comprising a plurality of cells, the cells at least partially forming a porous and / or hollow structure.

[0020] The pore structure of at least one buffer layer can give at least one top layer elasticity. The pore structure of at least one buffer layer is preferably able to bend, thereby reducing the impact force when an individual or an object falls, especially when using panels on the floor. Typically, the semi-rigid top layer disperses the energy generated by the impact to its surface and gradually dissipates the energy on the top layer before the energy is transferred to the at least one pore structure of the at least one buffer layer. The energy is then dissipated in a controlled manner through the at least one pore structure, so that optimal absorption of the above energy is achieved in the at least one buffer layer. This improves the energy recovery capacity of the panel, because the percentage of energy returned to the energy applied during the impact is correspondingly reduced. Therefore, the risk of injury to the faller during the impact or damage to the fallen object is reduced. On the other hand, the convenience of moving on the floor is also improved, thereby providing more comfort for people with physical disabilities.

[0021] It is conceivable that at least one buffer layer comprises a composite structure, the composite structure comprising at least one honeycomb structure, at least one foamed structure and / or at least one grid structure. It is conceivable that at least a portion of at least one pore structure of at least one buffer layer is defined as a honeycomb structure, a bubble protection plate, a corrugated plate, a corrugated structure and / or a double-walled structure. At least a portion of at least one supporting structure defining any of the structures can further contribute to the strength and / or stiffness of the panel. For example, it is conceivable that the walls defining the honeycomb structure, the bubble protection plate, the corrugated plate, the corrugated structure and / or the double-walled structure extend over the thickness of the buffer layer. It is also conceivable that the walls defining the honeycomb structure, the bubble protection plate, the corrugated plate, the corrugated structure and / or the double-walled structure extend at an angle, in particular substantially perpendicular to the plane defined by the front and / or rear surfaces of the panel, preferably substantially perpendicular to the plane defined by the buffer layer. For example, the honeycomb structure can be a thermoplastic honeycomb structure in a buckling orientation. However, another embodiment can also be envisioned, in which the panel comprises at least one additional buffer layer or a secondary buffer layer. At least one secondary buffer layer can be a separate layer in addition to at least one core layer. It is also conceivable that at least one secondary buffer layer is arranged adjacent to at least one core layer and / or forms part of at least one core layer. At least one secondary buffer layer may be defined as any one of the embodiments of the buffer layer according to the present invention. Further embodiments are also conceivable, in which at least a portion of at least one pore structure of at least one buffer layer is defined as a grid. The pore structure of at least one buffer layer preferably extends over the entire buffer layer. Therefore, it is conceivable that the pore structure defining the grid extends over the entire buffer layer. At least a portion of the pore structure of at least one buffer layer may be filled with at least one porous material.

[0022] At least one buffer layer may include at least one pore structure including a gradient structure. For example, at least one buffer layer is defined to include a gradient discrete structure, a gradient increasing structure and / or a gradient decreasing structure over the thickness of the buffer layer. It is also conceivable that at least one pore structure may form a random structure in which the units have different sizes (i.e. a Voronoi-tessellation structure), a non-uniform structure and / or a periodic structure. It is conceivable that the non-uniform structure forms a gradient structure, in particular a discrete gradient (i.e. low-high-low, high-low-high), an increasing gradient (i.e. from low to high), a decreasing gradient (i.e. from high to low) or a combination thereof, thereby exhibiting an expected force reduction effect and / or improving the impact force dissipation during an impact, thereby making the floor or building panel safer.

[0023] In a preferred embodiment, at least one buffer layer includes at least one metamaterial that can impart excellent mechanical strength and impact energy absorption capabilities to the building panel. Preferably, at least one metamaterial used in the buffer layer or in some cases in any part of the panel is a composite material or composite medium composed of micro- or nano-particle building blocks with a repeating pattern to interact with sound waves or external forces (such as compression or impact) to produce beneficial effects such as sound attenuation, shock absorption, impact reduction, or a combination thereof. The at least one metamaterial is preferably selected from the group of liquid crystal elastomers (LCEs), foam-based LCEs, high energy absorption LCEs, shell lattice (SL) metamaterials, bending-dominated metamaterials, stretch-dominated metamaterials, octahedral lattice materials, frame lattice materials, shell-like materials, noise reduction materials, or a combination thereof. In a possible embodiment, at least one metamaterial effectively functions as a shock absorbing or buffering material by virtue of the geometry of its subunits. In this case, the metamaterials that can be used can be divided into auxetic metamaterials, such as re-entrant structure, 3D buckyball, fiber network mat, crystalline rolled-up tube; pentamode metamaterials, such as pentamode structure and kagome structure; soft template printing, such as holey sheet and biholar sheet; cellular origami, such as stacked miura-ori and staggered miura-ori; origami metamaterials, such as miura-ori tessellated pattern, non-periodic Ron Resch pattern, square twist and kirigami; chiral systems, such as trichirality, tetrachirality and hexachirality; micro / nano lattices, such as stretch-dominated octahedron and bend-dominated tetradecahedron; and / or combinations thereof. By using at least one metamaterial in at least one buffer layer, the mechanical properties that lead to the shock absorption and / or buffering effect can be modified to obtain optimal performance. These properties include stiffness, hardness and compressibility of the metamaterial or buffer layer, which are dependent on Poisson's ratio, shear / bulk modulus, Young's modulus or a combination thereof. In a preferred embodiment, at least one metamaterial constituting at least a portion of at least one buffer layer is manufactured by subtractive manufacturing and / or additive manufacturing (AM), such as selective laser melting (SLM), or a combination thereof. These manufacturing methods can produce high-strength lightweight structures with complex geometries that are difficult to manufacture using traditional manufacturing methods.

[0024] According to the invention, it is envisaged and preferred that at least a portion of the buffer layer comprises a building material having an at least partially anisotropic structure. It is envisaged that the anisotropic structure has different physical properties, such as stiffness, compression resistance, compliance, expansion and / or swelling, depending on the measurement axis, which can provide at least part of the panel with asymmetric properties, such as high strength in the horizontal plane and high elasticity or compliance in the vertical plane, which may be particularly advantageous when used in combination with an interlocking mechanism, while still being able to absorb impact forces.

[0025] The panel may also include a plurality of buffer layers, each buffer layer including at least one pore structure, in particular at least one porous structure. If this embodiment is adopted, preferably the compressibility of at least one first buffer layer is greater than the compressibility of at least one second buffer layer. For example, the compressibility of at least one first buffer layer located between the second buffer layer and at least one top layer may be greater than the compressibility of at least one second buffer layer.

[0026] In a preferred embodiment, for example, at least part of the pore structure of at least one buffer layer may have a repeating pattern or any polygonal or n-sided matrix. The pore structure may be defined as a matrix, which may result in hollow portions and / or cavities in the pore structure, thereby forming a porous porous structure layer. In this case, it is conceivable that at least a portion of the hollow portions and / or cavities are filled with at least one filling material. The use of fillers in these hollow portions can further improve the cushioning effect, thereby making the floor more comfortable and safer. Non-limiting examples of filling materials include foam particles, foamed polymers, expanded polystyrene (EPS) or expanded styrene, foamed polypropylene, memory foam, micro / nano beads, foam fillers, polyethylene (PVC) particles, soft filling materials or combinations thereof. In another example, at least one pore structure layer includes a matrix structure. For example, at least a portion of at least one pore structure layer may include a honeycomb structure and / or any polygonal or n-sided matrix. Using this configuration can play a positive role in the force distribution during impact.

[0027] It is also conceivable that at least one buffer layer is formed by or comprises a gel and / or a gel layer. At least one pore structure of at least one buffer layer may also be formed by or comprise at least part of a gel layer. For example, such a gel layer may be a very viscous gel layer. This may allow the gel layer to remain in place without the interference of an adhesive. For example, at least one gel layer may be a gel blanket or a gel pad. For example, the gel layer may comprise silicon and / or polyurethane.

[0028] The at least one buffer layer may have a Shore A hardness of 75 or less, preferably 65 or less, more preferably 55 or less. For example, the at least one buffer layer may have a Shore A hardness in the range of 45 to 65. In an advantageous embodiment, the at least one buffer layer has a Shore A hardness of at most 55. At least one buffer layer having a Shore A hardness of 75 or less is generally configured to be temporarily deformed, in particular compressed. It has been found that this range of Shore A hardness values ​​exhibits the most ideal properties in terms of alleviating impact pressure and further absorbing energy transferred from the decorative top layer. The at least one buffer layer or the at least one porous structure layer will generally have a positive effect on the impact absorption and sound attenuation of the panel.

[0029] The compressive strength of at least one buffer layer can be measured according to the EN 826 standard. Compressive strength indicates the ability of a material to deform locally at a point of compression when a vertical force acts on the surface of the material. According to this test method, a Shore A hardness of 75 is roughly equivalent to 445psi or 3Mpa. Preferably, at least one buffer layer has a compressive strength of less than 400kPa, preferably less than 200kPa. At least one buffer layer with a compressive strength of less than 200kPa allows deformation and can return to its original state relatively quickly after being stressed. The use of such at least one buffer layer can further promote the absorption and / or conversion of impact kinetic energy, thereby significantly reducing the amplitude and pitch of the sound generated. Experiments have found that good results can be achieved using such a buffer layer. It is also conceivable that at least one buffer layer has a memory effect when indented.

[0030] It is conceivable that at least one of the pore structures or porous structures contains or forms a substantially hollow structure, which, in addition to minimizing damage and reducing the risk of injury, can effectively dissipate and absorb energy when impacted. It is conceivable that such a structure includes a macroporous structure (such as perforation) and / or a smaller aperture to enhance the dissipation of the kinetic energy generated by the impact. Such a structure of the buffer layer can more effectively capture or reverberate sound waves, acting as an energy capture barrier or noise barrier, confining energy and / or sound waves to the volume between the rigid boundary and the reflective surface. At least one buffer layer is conceived to reduce the kinetic energy intensity of the drop impact and the amplitude of the sound waves reflected from the drop. The kinetic energy and / or sound waves are superimposed on the kinetic energy and / or sound waves transmitted to the panel and produce a resonance effect on the panel, so that the resonance effect is also weakened. In addition, the surface of at least one buffer layer facing the incident impact and / or sound waves can effectively dissipate energy and / or absorb low frequencies of sound waves to control the direction of multiple reflections of sound waves. As mechanical kinetic energy propagates through the pores of the material, the mechanical energy generated by the impact and / or sound waves penetrating the perforations of the macrostructure layer allows energy dissipation, sound absorption, reflection and friction, thereby achieving a dissipative and / or sound absorbing effect.

[0031] It is also conceivable that at least one buffer layer comprises at least two pore structures. It is also conceivable that an intermediate layer is arranged between at least two pore structure layers. Preferably, the intermediate layer acts as a conduit or means for connecting at least one pore structure layer.

[0032] In another embodiment of the present disclosure, the hole structure layer includes a perforated array, and the perforated array is sandwiched between two hole structure layers to completely decouple the layers so that the perforated array increases the dissipation of kinetic energy and, due to the significant difference in material density, helps to resist the vibration of incident sound waves that pass through the depth of the perforated array. Similarly, this configuration can also form a mass-air or mass-air-mass structure, which can also reduce the impact force of a fall and resist the passage of incident sound waves through the wall panel.

[0033] The density of the at least one buffer layer or the at least one pore structure is usually lower than the density of the top layer. For example, it is conceivable that the density of the at least one buffer layer is at least 50% lower than the density of the top layer, preferably at least 70% lower, more preferably at least 90% lower than the density of the top layer. Due to this difference in density of the at least one buffer layer and the top layer, an optimal combination of sufficient structural rigidity resulting from a higher density of the top layer and an average lower density of the buffer layer can be achieved. As a result, the impact sensitivity of the at least one top layer is optimized. The average density of the at least one buffer layer may be 25 kg / m 3 Up to 350kg / m 3 It is conceivable that at least one buffer layer has a density of at least 25 kg / m 3 and / or up to 350kg / m 3 For example, the density of at least one buffer layer may be at least 60 kg / m 3 Up to 300kg / m 3 , preferably at least 60 kg / m 3 Up to 275kg / m 3 . Experiments have found that when the density is lower than 25kg / m 3 When the energy dissipation capacity of at least one buffer layer decreases, the density range is at least about 25 kg / m 3 Up to 350kg / m 3 The best performance is shown when

[0034] The thickness of at least one buffer layer is preferably in the range of 1 to 8 mm, for example in the range of 3 to 7 mm. The thickness of at least one buffer layer or at least one of its pore structures may be less than the thickness of at least one top layer and / or at least one top layer. In addition, it is also conceivable that the thickness of at least one buffer layer is greater than the thickness of at least one decorative layer and / or the core layer. Depending in part on the material used, the thickness of at least one pore structure of at least one buffer layer relative to the top layer ensures that the top layer is not too rigid, thereby reducing the elasticity of the pore structure. The thickness of at least one buffer layer or at least one of its pore structures is in the range of 0.8 to 3 mm, preferably in the range of 1.2 to 2 mm. It is also possible that the thickness of at least one pore structure and / or at least one buffer layer is in the range of 0.5 mm to 2 mm, preferably in the range of 0.75 mm to 1.5 mm.

[0035] In one possible embodiment, at least one buffer layer includes at least one pore structure, which bends, folds and / or compresses when subjected to an axial impact force or load force. Compared with conventional panels, at least one pore structure has compressive resistance, thereby having excellent impact absorption performance, specifically manifested as lower Gmax and lower HIC. The compressive resistance of at least one pore structure can be attributed to the bending-dominated nature of the structure, which enables at least one pore structure to gradually dissipate the initial force or acceleration to which the individual or object is subjected during the impact process during the elastic and / or plastic deformation stage. It was found experimentally that at least one pore structure of the buffer layer effectively absorbs the impact force in an elastic manner in a first time period until a certain yield point is reached, and then dissipates the remaining impact force in the buffer layer in a second time period, ensuring that the remaining impact force is absorbed at a continuous rate. Therefore, the energy recovery capacity in the panel is significantly improved, and the energy returned by the panel is reduced compared to the energy applied when the individual or object hits the panel, thereby minimizing the risk of injury or damage to the individual or object. Obviously, at least one pore structure of the buffer layer exhibits effectively balanced inertial sensitivity and strain rate sensitivity, so that the panel of the present invention exhibits continuous deformation. It is conceivable that when subjected to an out-of-plane load or force, at least one pore structure exhibits at least elastic deformation in a first time period, plastic deformation in a second time period, and / or a densification stage in a third time period. In the first time period or elastic deformation stage, the response of the buffer layer can be linear until the elastic limit, yield point and / or threshold displacement, after which the buckling, compaction and / or folding of the buffer layer can be manifested by plastic deformation in the second time period. Preferably, the typical feature of the plastic deformation stage is a nearly constant force-displacement curve. Once the buffer layer is deformed enough to contact other components, thereby limiting further deformation, the densification deformation stage is reached in the third time period.

[0036] In a preferred embodiment, at least one pore structure of the buffer layer is specially designed to exhibit elastic deformation in at least a first time period, plastic deformation in a second time period, and / or a densification stage in a third time period when subjected to compression of an out-of-plane load or force. Therefore, it is conceivable that at least one pore structure of the buffer layer includes at least one unit having at least one pore wall. Preferably, at least one porous structure is selected from the group of 2.5D structures, foamed structures and / or 3D or grid structures. In one embodiment of the present invention, it is conceivable that at least one pore structure is a 2.5D structure, which can be selected from a two-dimensional pore structure formed and / or extruded in three dimensions and / or a two-dimensional planar material formed, extruded and / or thermoformed in a manner that introduces three dimensions. It is conceivable that the 2.5D structure includes a plurality of units of similar shape and size, however, in some cases, the units have non-repeating shapes and / or sizes, which can be adjusted according to a predetermined sound frequency to improve attenuation, absorption or sound insulation. In another example, the porous structure, more preferably a 2.5D structure, includes any polygon or "n"-sided matrix, where n is an integer representing the number of polygon sides. It is conceivable that the 2.5D structure at least partially forms a honeycomb or hexagonal structure. Preferably, the honeycomb or hexagonal structure is in a buckling orientation. Using this configuration can play a positive role in the force distribution during impact. It is envisioned that the honeycomb structure, hexagonal structure and / or polygonal or n-gonal matrix can dissipate energy with lower thickness and higher specific strength. In another embodiment of the present invention, the porous structure and / or 2.5D structure can also include honeycomb tubes, honeycomb die, cylindrical stamping die, zigzag pattern, wavy pattern, honeycomb board (corriboard), corrugated board, grooved plastic, corrugated plastic, corrugated polypropylene, pipes, grooves, surface cavities or cylinders of different sizes, etc. Similarly, the size of the honeycomb structure or polygonal or n-matrix is ​​also likely to affect the dissipation and / or reflection direction of mechanical kinetic energy, thereby causing destructive interference of mechanical kinetic energy, so that the kinetic energy is dissipated through the panel. It is also conceivable that the honeycomb structure or polygonal or n-matrix can be at least partially made of aluminum or other lightweight materials to provide an excellent strength-to-weight ratio. Preferably, the combination of aluminum and honeycomb structure (especially hexagonal honeycomb structure) provides excellent load-bearing capacity, so that the buffer layer and the entire panel can withstand huge impact forces and can more evenly and effectively disperse the impact forces to the buffer layer and the entire panel.

[0037] As you can imagine, the strength-to-weight ratio of a 2.5D structure is 50MPa*cm 3 / g to 400MPa*cm 3 / g, preferably 55MPa*cm 3 / g to 300MPa*cm 3 / g, more preferably 60MPa*cm3 / g to 250MPa*cm 3 / g range. Experiments have found that within these strength-to-weight ratio ranges, at least one buffer layer can provide optimal structural stability and stiffness without weakening the panel's buffering capacity and compliance to the human body, thereby enabling the panel to absorb a large amount of impact force when a fall occurs. In the case of using a foam structure, it is conceivable that the foam structure includes units with randomly generated shapes and randomly oriented pore walls. The foam structure may include at least one material selected from the following groups: closed-cell foam, open-cell foam, compressible natural material and / or compressible elastomer. The pore foam material may also be a closed-cell soft foam. Optionally, the buffer layer may also include at least one spring-like material, a rebound layer, a compressible layer or any device or buffer-like material for buffering. At least one pore structure layer may also include at least one material selected from the following groups: polyolefin foam, expanded polystyrene, expanded polypropylene, (foamed) rubber, ethylene-vinyl acetate copolymer (EVA), irradiated cross-linked polyethylene (IXPE) and / or expanded polyethylene. It may also be polypropylene (XPP) and / or expanded polystyrene (XPS). In a preferred embodiment, at least one pore structure layer includes at least 50% foam material, such as but not limited to closed-cell foam material. Alternatively, the pore structure layer contains at least 80% foam material, in particular closed-cell foam material. Closed-cell foam material is conducive to achieving the intended purpose because such material has sufficient compressibility and sufficient strength to support the decorative top layer and load when applied. For example, at least a portion of at least one pore structure layer can be made of closed-cell soft foam material. At least one pore structure layer can also include semi-closed-cell or open-cell compressible foam. The open-cell structure has the advantage of improving the sound absorption effect. The pore structure layer can also be a solid layer. Therefore, the compressible layer can also be non-foamed. In this case, the best effect can be obtained by using materials selected from the group of flexible polymers and elastomers, including but not limited to: rubber, latex, acrylic elastic epoxy resin, cis-polyisoprene (natural rubber, NR), cis-polybutadiene (butadiene rubber, BR), nitrile rubber (NBR), styrene-butadiene rubber (SBR), rubber, latex and / or ethylene propylene monomer (EPM). It is also possible to envision an embodiment in which at least one porous structure layer comprises gel, rubber and / or silicon. It is also possible to use a combination of foamed or non-foamed materials among the above materials. For example, at least one porous structure layer may also comprise at least one compressible natural material, such as but not limited to: felt, cotton, wool, mycelium, hemp, cork and / or similar materials. These examples are non-limiting and any similar foam material with equivalent material properties may be used. However, in another possible embodiment, at least one porous structure layer comprises a gel layer.

[0038] In another embodiment, it is conceivable that if a grid structure is applied, the grid structure includes a spatially periodic array of cells having interconnected edges and faces and / or interconnected pillars and nodes. It has been found that the formation of such a grid structure can provide sufficient stiffness and strength to the buffer layer while ensuring that the buffer layer has a high energy absorption capacity. Preferably, the grid structure of the present invention has a bending-dominated mechanical response, wherein the grid structure is subjected to bending moments within the buffer layer, thereby making the buffer layer compliant. It is conceivable that the Maxwell number M of the grid structure is less than zero, or in other words, there are too few pillars to balance the induced moments at the structural nodes and balance the impact forces, resulting in bending stresses in the pillars and a bending-dominated mechanical response. For a structure consisting of s pillars or walls and n nodes, connection points or folds, the Maxwell number MN = s-3n+6, where M>0 exhibits rigidity and non-compliant behavior, while MN≤0 exhibits compliance and bending dominance. In a preferred embodiment, according to experimental data, MN of at least part of the pore structure, grid structure, 2.5-dimensional constructed material and / or 3-dimensional constructed material is ≤0, preferably ≤-2, more preferably ≤-4, or compliance and bending are dominant.

[0039] It is conceivable that the pore structure of at least one buffer layer includes a 2.5D, 2.5-dimensional structure and / or a planar constructed material. By having a 2.5-dimensional continuous grid structure, the grid structure is formed by multiple folding points and multiple pore walls or pillars that are repeated at least once on at least one axis. Experiments have found that due to the structural uniformity of the 2.5D grid structure, a controlled folding response can be achieved, wherein the buffer layer exhibits optimal and progressive impact / energy absorption while allowing fine-tuning of the precise Fmax, yield point or displacement threshold exhibited by the structure. It is conceivable that the pore structure has a 3D or grid structure and / or a 2.5D structure comprising multiple faces or pillars and folding points or nodes, wherein the faces or pillars are at an oblique angle to the axial impact force and will exhibit a gradual reduction in the impact force or a gradual dissipation of the impact force, while the faces or pillars parallel to the axial impact force will not exhibit a gradual reduction in the impact force. Therefore, the angle of the face or pillar relative to the axial impact force will greatly affect the gradual dissipation of the impact force in the pore structure. When the faces or struts are angled with respect to the axial impact force, they spread the impact force over a larger area, allowing for controlled deformation, thereby promoting gradual dissipation of the impact force. In this configuration, the forces are generated in a diagonal direction along the lattice planes, which helps absorb energy and reduce peak forces. It has been found experimentally that, in accordance with the present invention, the angle in the range of 30 to 60 degrees relative to the axial impact force is steep enough to provide structural stability and therefore provide a suitably high Fmax, threshold and / or displacement threshold, but is also sufficiently inclined to promote gradual dissipation.

[0040] It is conceivable that the hole structure or grid structure includes a three-dimensional constructed material. As a three-dimensional constructed material, the grid structure is formed by a plurality of nodes and a plurality of hole walls or pillars repeated at least once on at least two axes. In some configurations, the plurality of pillars or hole walls include at least one folding point. In addition, the pillars and / or hole walls are inclined relative to the expected impact force direction, in particular, they are inclined at 30 to 60 degrees relative to the expected impact force direction to avoid weak points of the pillars and / or hole walls. By following this construction, the impact force is dissipated in the structure in a preferred manner, thereby enhancing the safety performance of the panel. It is conceivable that this three-dimensional constructed material is a metamaterial, an artificial periodic structure, such as a perforated honeycomb-corrugated hybrid carrier, a micro-perforated panel, a spiral structure acoustic metamaterial and / or an acoustic silencing metamaterial of an open noise reduction structure, which can provide excellent mechanical strength and impact energy absorption capacity for building panels. Preferably, at least one metamaterial used in the buffer layer, or in some cases in any portion of the panel, is a composite material or composite medium comprised of micro- or nanoparticle building blocks having a repeating pattern to interact with sound waves or external forces such as compression or impact to produce a beneficial effect such as sound attenuation, vibration reduction, impact reduction, or a combination thereof.

[0041] At least one metamaterial may include a group selected from liquid crystal elastomer (LCE), foam-based LCE, high energy absorption LCE, shell lattice (SL) metamaterial, bending-dominated metamaterial, stretch-dominated metamaterial, octahedral lattice material, frame lattice material, shell-like material, noise reduction material or a combination thereof. In one possible embodiment, at least one metamaterial effectively functions as a shock absorbing or cushioning material by virtue of the geometry of its subunits. In this case, the metamaterials that can be used can be divided into auxetic metamaterials, such as re-entrant structure, 3D buckyball, fiber network mat, crystalline rolled-up tube; pentamode metamaterials, such as pentamode structure and kagome structure; soft template printing, such as holey sheet and biholar sheet; cellular origami, such as stacked miuri-ori and staggered miura origami; origami metamaterials, such as miura-oritessellated pattern, non-periodic Ron Resch pattern, square twist and kirigami; chiral systems, such as trichirality, tetrachirality and hexachirality; micro / nano lattices, such as stretch-dominated octahedron and bend-dominated tetradecahedron; and / or combinations thereof. By using at least one metamaterial and / or architected material in at least one buffer layer, the mechanical properties that lead to the shock absorbing and / or buffering effect can be modified to obtain optimal performance. These properties include stiffness, hardness and compressibility of the metamaterial or buffer layer, which are dependent on Poisson's ratio, shear / bulk modulus, Young's modulus or a combination thereof. In a preferred embodiment, at least one metamaterial and / or architected material that constitutes at least a portion of at least one buffer layer is manufactured by subtractive manufacturing and / or additive manufacturing (AM), such as selective laser melting (SLM), or a combination thereof. These manufacturing methods can produce high-strength lightweight structures with complex geometries that are difficult to manufacture using traditional manufacturing methods.

[0042] We also envision that the interconnected edges and faces are similar to crystal structures, such as face-centered cubic (FCC), body-centered cubic (BCC) and hexagonal close-packed (HCP) structures. The shapes and sizes in the unit can be uniform or uneven. The above structure defines the structure of the porous layer, such as the number of contact points between adjacent pore structures. For example, by following the BCC structure, the buffer layer includes adjacent pore structures that are interconnected at least at 8 corner positions. When the FCC structure is used, there are at least 14 connection points between the individual pore structures that constitute the buffer layer, which are the sum of 8 corner points and 6 center points of the cubic structure. The HCP structure can also be used in the porous structure of the buffer layer, wherein the top and bottom surfaces of the hexagonal structure have 12 corner points and 2 center points. In another preferred embodiment, the porous structure layer is selected from a group consisting of a cubic structure, a hexagonal lattice structure, an origami structure, a folded structure or a combination thereof.

[0043] The flexibility of flooring layers (e.g. top layer, cushioning layer and / or core layer) is usually measured according to EN 310 or ASTM D790. Flexibility measured according to the above standards refers to the ability of a material to withstand deformation when a vertical force is applied to its surface. The hardness of the panel layer can be further measured using a durometer. In this method, the higher the number, the higher the hardness. Hardness indicates the ability of the material being tested to deform locally at the pressure point when a vertical force is applied to its surface. Shore A hardness is usually used to measure softer materials and uses a blunt needle tip, while Shore D hardness is used to measure medium to hard surfaces and uses a needle tip with a 30° sharp angle at the end. In general, Shore A hardness can be divided into very soft (0-40), soft (40-75) and medium hard (75-95); Shore D hardness can be divided into soft (8-25), medium hard (25-46) and hard (46-90). There is some overlap between the two grades. The (soft) Shore A hardness of 40 to 75 is similar to the Shore D hardness of 8 to 25; the (medium hard) Shore A hardness of 75 to 95 is similar to the Shore D hardness of 25 to 46.

[0044] At least one top layer, in particular the upper surface of at least one top layer, has a Shore D hardness of at least 60. However, it is also conceivable that, in another embodiment, the decorative top layer, in particular the upper surface of at least one decorative top layer, has a Shore D hardness in the range of 70-100, preferably in the range of 75-85. These hardness ranges are sufficient to achieve the technical effect required by the present invention. The Shore D hardness of at least one top layer is preferably in the range of 60-90, more preferably in the range of 60-75. Such a panel benefits from a balance between rigidity and flexibility, since at least one top layer has a Shore D hardness of at least 60, preferably in the range of 70-85, and / or is semi-rigid, which according to the present invention is understood to have an elastic modulus of 1800 MPa to 5500 MPa when tested according to EN 310 standard, and / or is flexible around a mandrel with a diameter in the range of 50-350 mm when tested according to ASTM F137 standard, or has a flexibility of 50-350 mm in a mandrel test according to ASTM F137. If the panels are used as flooring, the panels according to the invention have the advantage of at least one cushioning layer which dissipates the kinetic energy exerted on the flooring in the event of an impact, thereby reducing the impact forces. Surprisingly, the use of panels having a semi-rigid top layer in combination with a cushioning layer sandwiched between the top layer and at least one core layer surprisingly reduces the impact forces of a fall compared to alternatives available on the market, such as panels having only a core layer and a flexible decorative top layer, or panels having a core layer and a flexible decorative top layer and a compressible intermediate layer. Due to the Shore D hardness and elastic modulus of the top layer, it is also possible to apply a relatively thin decorative top layer while achieving the desired effect.

[0045] In a preferred embodiment, at least one top layer has an elastic modulus of at least 1800 MPa to 5500 MPa. In another embodiment, according to the EN 310 standard, at least one top layer has an elastic modulus of at least 1800 MPa to 9000 MPa. In another possible embodiment, the elastic modulus of at least one top layer is between 5000 MPa and 6000 MPa. Other possible values ​​are an elastic modulus of at least 2500 MPa or at least 4000 MPa. In addition, in a mandrel test according to the ASTM F137 standard, at least one top layer has a flexibility of 50 to 350 mm. This means that when tested according to the ASTM F137 standard, the top layer has flexibility around a mandrel with a diameter of 50 to 350 mm. In a preferred embodiment, at least one top layer has flexibility around a mandrel with a diameter of 50 to 125 mm or 50 to 76 mm. The top layer is preferably not flexible, which means that the test result is at least 50 mm when tested according to the ASTM F137 standard. The (decorative) top layer is preferably semi-rigid. It has been found that, according to the invention, this combination of flexibility / rigidity range, in particular in combination with this range of elastic modulus, is one reason why at least one decorative top layer has a significantly improved performance when an individual or an object falls on the floor. More specifically, this combination of elastic modulus and hardness allows the impact energy generated by an individual or an object falling on the floor to be at least partially dissipated or absorbed in the system consisting of the decorative top layer and the buffer layer. This means that the energy is first dispersed to an area of ​​the decorative top layer and then transferred to a larger area of ​​the buffer layer. The partial dissipation or absorption of the energy generated by the impact by the decorative top layer reduces the reaction force exerted by the floor on the impacting individual or object, thereby also reducing the energy returned by the floor during the impact. As a result, the energy recovery in the panel is gradually improved, thereby reducing or minimizing the risk of injury to an individual falling on the panel of the invention. In addition, the ease of movement on the floor is also improved, thereby providing relatively more comfort for those with physical disabilities and being able to withstand pressure exerted on small surfaces, such as wheelchairs or electric chairs.

[0046] The panel of the present invention may be referred to as a hard surface floor panel and is suitable for constructing floor coverings. When tested according to ASTM F1292-09, the panel preferably has a G-max value of less than 150, preferably less than 120G and / or a HIC (Head Injury Criteria) of less than 800, preferably less than 600, and more preferably less than 500. Experimental results supporting this embodiment are shown in Table 1 below.

[0047] Table 1 G-max and HIC results

[0048]

[0049]

[0050] G-max is defined as the maximum acceleration of the impactor during the impact, expressed in G units. HIC is defined as the specific integral of the impact acceleration-time history and is used to determine the relative risk of head injury. The lethal limit of G-max is defined as 200G, while the lethal limit of HIC is 1000. Due to the combination of the decorative top layer and the buffer layer, the floor panels of the present invention provide adequate scores in these tests. In addition to having good impact resistance, lower G-max and HIC values ​​compared to traditional hard floors or hard surface floor panels, the floor panels of the present invention also provide a comfortable walking and playing experience.

[0051] At least one top layer is preferably a decorative top layer. At least one top layer may comprise at least one polymer material and preferably at least one mineral filler. It is also conceivable that at least one top layer comprises multiple layers of resin-impregnated paper or at least one cellulose-based material (selected from at least one wood veneer and / or at least one bamboo veneer). At least one decorative top layer may also comprise at least one decorative layer. At least one decorative top layer may comprise a digitally printed decorative layer. In one embodiment, at least one decorative top layer comprises at least one polymer material, preferably at least one mineral filler. The thickness of at least one top layer is preferably in the range of 0.05 to 5 mm, preferably in the range of 1 to 4.5 mm, more preferably in the range of 1.5 to 4 mm. The thickness of at least one top layer may also be in the range of 0.1 to 2 mm. It is also conceivable that the thickness of at least one top layer is between 1 to 4 mm or between 1.5 and 3 mm. Typically, the thickness of the decorative top layer is less than 3.5 mm, preferably less than 3 mm. It is beneficial to use a relatively thin but semi-rigid top layer. This will have a positive effect on the influence of forces and the distribution of forces.

[0052] At least one (decorative) top layer preferably has a surface area of ​​at least 1000 kg / m 3 For example, the density of the top layer should be at least 1000 kg / m 3 , preferably at least 1200 kg / m 3 , 1300kg / m 3 or 1400kg / m 3 This range of values ​​for the top layer density ensures that, when used as a floor panel, a simple impact or shock to the floor panel does not affect its ability to cushion future impacts, or that the floor panel is not too rigid to be damaged in a fall impact.

[0053] In one possible embodiment, at least one decorative top layer comprises at least one cellulose-based material. At least one decorative top layer may also comprise at least one paper layer printed with a decorative pattern. It is conceivable that if such paper is used, it is flexible and / or compatible with rollers. At least one decorative top layer may include at least one wood veneer and / or at least one bamboo veneer. The decorative top layer may also include multiple layers of resin-impregnated paper or wood veneer. The decorative top layer may be in the form of multiple superimposed layers, multi-oriented layers, closed layers, fiber layers, fiber webs, interlaced fibers, woven structures or mesh structures. It is also conceivable that at least one decorative top layer comprises at least one substantially transparent wear layer or protective finish. The wear layer may include one or more layers of transparent thermoplastic or thermosetting resin. Non-limiting examples of usable thermoplastic or thermosetting materials include polyvinyl chloride (PVC), polystyrene (PS), polyethylene (PE), polyurethane (PU), acrylonitrile-butadiene-styrene (ABS), polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene triethylene terephthalate (PTT), polyethylene naphthalate (PEN), phenolic resin and / or melamine resin or formaldehyde resin. The wear-resistant layer can also be made of a thermosetting resin (such as but not limited to phenolic resin and / or melamine or formaldehyde resin) in liquid or paste form. The wear-resistant layer can include or be mainly composed of an inherent scratch-resistant thermosetting resin impregnated carrier layer (such as paper or lignocellulose). An advantage of the latter embodiment is that the urea-formaldehyde resin also acts as a relatively scratch-resistant wear-resistant layer. Typically, the thickness of the wear layer structure in the panel of the present invention is preferably in the range of 0.1 to 2.0 mm, more preferably between 0.15 and 1 mm, and more preferably between 0.2 and 0.8 mm. It is conceivable that the thickness of the wear layer is greater than the decorative layer. For example, the thickness of at least one wear layer may be between 0.15 and 1 mm. In this embodiment, the total thickness of the decorative top layer is typically between 0.17 and 1.07 mm. For example, the at least one wear layer may partially cover the upper surface of the decorative layer, more preferably at least 50% of the upper surface of the decorative layer, and most preferably the at least one wear layer covers the entire upper surface of the decorative layer. It is conceivable that the at least one wear layer may further include abrasive materials to improve its wear resistance. Non-limiting examples of the abrasive materials include aluminum oxide (such as quartz), silicon dioxide, corundum, silicon carbide, glass, glass beads, glass balls, diamond particles, hard plastics, reinforced polymers and organics, or combinations thereof. For example, at least one wear layer may be based on any thermoplastic or thermosetting material. The wear layer may also include fillers, for example based on calcium, carbonate or magnesium. The decorative top layer may also consist of a layer of a carrier material designed to carry a decorative pattern. The carrier material may be a woven, extruded or calendered plastic mesh, sheet or film.Non-limiting examples of thermoplastic or thermosetting materials that can be used include polyvinyl chloride (PVC), polystyrene (PS), polyethylene (PE), polyurethane (PU), acrylonitrile-butadiene-styrene (ABS), polypropylene (PP), polybutylene terephthalate (PBT), polyethylene trimethyl terephthalate (PTT), polyethylene naphthalate (PEN), phenolic resin and / or melamine resin or formaldehyde resin, etc. The panel preferably includes at least one pair of opposite sides, on which are arranged interconnected and / or complementary connecting parts for connecting adjacent panels. The interconnected connecting parts may constitute a part of at least one decorative top layer, at least one buffer layer and / or at least one core layer. For example, the connecting parts of the panel may be interlocking connecting parts, preferably configured to provide both horizontal and vertical locking. Interlocking connecting parts are connecting parts that require elastic deformation, snap-fit ​​or multi-directional movement to connect or separate parts to each other. Any suitable interlocking connecting parts known in the art can be applied. A non-limiting example is an embodiment wherein a first side of the first pair of opposing sides includes a first connecting member and a second side of the first pair of opposing sides includes a complementary second connecting member, wherein the connecting members allow multiple panels to be connected to each other; wherein the first connecting member includes a lateral tongue extending in a direction substantially parallel to a plane defined by the panels, wherein the second connecting member includes a groove configured to accommodate a lateral tongue of at least a portion of another panel, wherein the groove is defined by an upper lip and a lower lip.

[0054] Preferably, at least one top layer is located on or above at least one buffer layer. It is conceivable that there is no connection between the buffer layer and the decorative top layer. Another possible embodiment is that at least one decorative top layer is located on or above at least one buffer layer with the interference of an adhesive layer. In another possible embodiment, there are multiple contact points between the buffer layer and the decorative top layer. In this embodiment, it is also conceivable that a part of the decorative top layer is located on or above at least one buffer layer under the action of the adhesive layer, while there are defined connection points between the layers. For example, the top layer can be configured to contact the buffer layer when the buffer layer is recessed. It is also possible that at least one air gap exists between at least one part of the at least one decorative top layer and at least one buffer layer, in particular when at least no pressure is applied to the panel. In addition, it is also possible that an air gap exists between at least one part of the at least one buffer layer and at least one core layer, in particular when at least no pressure is applied to the panel. For example, it is conceivable that the top layer is connected to the core layer, in particular via at least part of their periphery. It is thus conceivable that the buffer layer is connected to at least a part of the core layer but not to the top layer, and vice versa. The buffer layer can also be made of a very adhesive material, in particular the adhesive can be omitted.

[0055] The panel of the present invention preferably comprises at least one core layer. The presence of the core layer can further improve the impact resistance and / or sound insulation performance of the panel. At least one core layer generally comprises at least one adhesive and at least one filler. The core layer may further comprise at least one additive. Preferably, in a non-limiting embodiment of the present invention, the panel may comprise any material, such as plastic, including polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyethylene terephthalate (PETg), polyurethane (PU), polybutylene terephthalate (PBT), polyethylene triethylene terephthalate (PTT), polyethylene naphthalate (PEN), (wood) plastic composites, mineral substances, magnesium oxide, gypsum, glass, sand, wood, mycelium or mixtures (or combinations) thereof. Preferably, the core layer comprises at least one filler selected from the following group: minerals (preferably calcium carbonate), talc, dolomite, calcite; and pigments, modifiers, fibers (e.g., glass fibers, wood, straw and / or hemp). The fibers can be loose fibers and / or interconnected fibers to form a woven layer or a non-woven layer. Preferably, the core layer also includes at least one additional filler selected from the group consisting of steel, glass, polypropylene, wood, acrylic, alumina, curaua, carbon, cellulose, coconut, Kevlar, nylon, perlon, polyethylene, PVA, asbestos, viburnum, bentonite, ATH, MDH and fique. This can further improve the strength of the panel and / or the waterproofness and / or fire resistance of the panel. The core layer can also include a combination or composite of any of the aforementioned materials. It is conceivable that the composite material includes at least 20% (by weight) of filler and / or 15% to 50% (by weight) of binder. This range has been found to ensure that the core layer has sufficient stability and strength while also having its necessary flexibility and being able to improve temperature resistance.

[0056] A non-limiting example of an applicable core layer is a composite core layer comprising at least one mineral material and at least one adhesive. For example, the core layer may comprise at least 60% by weight of mineral material, preferably at least 70% by weight of mineral material. The higher the mineral content, the higher the hardness of the core layer and thus the higher the hardness of the panel. In addition, due to the relatively large amount of mineral material, a relatively good temperature resistance can be obtained, in particular for conventional floorings with a mainly thermoplastic core layer. It is conceivable that at least one core layer comprises at least one mineral material selected from the following group: magnesium oxide, calcium carbonate, chalk, clay, calcium silicate and / or talc. As a further non-limiting example, limestone (such as calcium carbonate and magnesium carbonate) can be used as the mineral material of the core layer. The mineral material can be present in the form of a granular mineral filler.

[0057] In one embodiment, at least one core layer has a stiffness of less than 3500 MPa, preferably less than 2000 MPa, and / or a stiffness of less than 75 mm, preferably less than 50 mm, or a stiffness range of between 25 and 50 mm when tested according to the ASTM F137 standard. Panels with such core layers may be particularly suitable for adhesive installation. Core layers with a stiffness of 1800 to 9000 MPa, preferably 2500 to 5500 MPa, may also be used, especially when measured according to the EN310 standard or according to the ASTM D790 standard, and / or a stiffness range of 50 to 350 mm when tested according to the ASTM F137 standard. Such core layers benefit from sufficiently high stiffness to provide sufficient support for the decorative top layer and the porous structure layer, and to allow an interlocking mechanism to be provided. The core layer may further act as an impedance layer, thereby further hindering the propagation of sound, or further help provide a shock absorbing device for the panel. The core layer may also include at least one natural material, such as wood fiber, mycelium, wool, straw, hemp, etc. The core layer preferably has a density of at least 1200 kg / m 3 The density is preferably at least 1400 kg / m 3 For example, the density of the core layer can be between 1600 and 2100 kg / m 3 within the range.

[0058] In a preferred embodiment, at least a portion of the upper and / or lower surfaces of the core layer comprises a plurality of cavities. The cavities on the upper and / or lower surfaces of the core layer may further improve the performance of the panel. For example, the plurality of cavities may form a predetermined pattern, which may be a repeating cavity pattern. The upper and / or lower surfaces of the core layer preferably at least partially comprise a predetermined shock-absorbing cavity pattern. The depth, shape, size and / or angle of at least some of the cavities may vary. It is conceivable that these cavities have different depths, shapes, sizes and / or angles, intended to scatter sound waves of different frequencies. At least some of the cavities may be embossed cavities. For example, at least some of the cavities may be obtained by additive or subtractive manufacturing, pressing, embossing, rotary embossing and / or rotary (die) cutting. It is beneficial that the cavities appear in the central area of ​​the panel. At least one outer edge of the core layer, preferably all outer edges, are free of cavities. Therefore, it is conceivable that one or more cavities do not pass through the outer edge of the panel. For example, it is conceivable that there is at least 1 cm without a cavity from each outer edge of the panel. For example, the perimeter of the panel, in particular the perimeter of the core layer, is at least 2 cm free of cavities. If a core layer is used which comprises a plurality of cavities on the upper and / or lower surface of the core layer, the density is determined only by the actual material of the core layer, wherein the cavities are not taken into account. The thickness of the core layer is typically in the range of 2 to 20 mm, preferably in the range of 2 to 8 mm, more preferably in the range of 3 to 5 mm. Another non-limiting example is a core layer thickness in the range of 3.5 and 4.5 mm.

[0059] In one possible embodiment, the panel of the invention comprises at least two buffer layers between at least one core layer and at least one decorative top layer. In this embodiment, it is conceivable that at least one upper buffer layer and at least one lower buffer layer are separated by at least one intermediate layer. For example, the intermediate layer may be a reinforcement layer.

[0060] The at least one reinforcement layer may comprise an organic or inorganic material or a combination thereof, such as but not limited to polymers, glass, ceramics, minerals and metals. Any other embodiment mentioned in the present application may also be applicable. The at least one reinforcement layer may also function as a spacer element between the buffer layer and the decorative top layer.

[0061] In one possible embodiment, the reinforcement layer can be a multi-layer superposition layer, a multi-oriented multi-layer superposition layer, a closed layer, a porous layer, a fiber layer, a fiber mesh, a cross-woven fiber, a gel, a particle, a microbead, a bead, a foam layer, a mesh, a criss-cross mesh, a honeycomb mesh, a sheet, a film, a tube, a liquid-filled tube, a vacuum tube, a hollow tube, an aerogel-filled tube, a woven structure or a mesh structure. In another possible embodiment, a stack of the decorative top layer and the porous structure layer of the present invention can be used. For example, the panel can include a stack of at least two or three (decorative) top layers and at least two or three porous structure layers.

[0062] In a preferred embodiment, the panel comprises at least one backing layer adhered to the back of the core layer. The backing layer may also be referred to as an additional shock absorbing layer or damping layer. The backing layer is typically made of a polymer material such as ethylene vinyl acetate (EVA), irradiated cross-linked polyethylene (IXPE), expanded polypropylene (XPP) and / or expanded polystyrene (XPS), such as, but not limited to, a low density foam layer. However, it is also conceivable that the backing layer comprises non-woven fibers (such as natural fibers such as hemp or cork) and / or recycled / recyclable materials (such as PET, felt, recycled carpet, etc.).

[0063] A shock absorbing layer or backing layer helps to improve the impact resistance of the panel. The backing layer also helps to provide an optimal interface between the panel and the underlying surface to which the panel is applied and can provide a protective function to the core layer. It can also absorb some of the subfloor irregularities. If a backing layer is used, the density of the backing layer is preferably 65kg / m 3 and 300kg / m 3 In the range of 80kg / m 3 and 150kg / m 3The thickness of the backing layer is typically between 0.1 and 2.5 mm. Non-limiting examples of materials from which the backing layer can be made are polyethylene, cork, polyurethane and ethylene vinyl acetate. In one embodiment, it is also conceivable that the panel includes (on its back side) at least one balancing layer, typically consisting of at least one layer including lignocellulose and a cured resin, wood or bamboo veneer, etc. It is conceivable that the shock absorbing layer or backing layer of the present invention includes at least one buffer layer.

[0064] The invention further relates to a top layer for use in a panel according to the invention. The invention further relates to a buffer layer for use in a panel according to the invention. The decorative top layer and / or the buffer layer may be any of the embodiments described. The invention further relates to an assembly of at least one top layer and at least one buffer layer for use in a panel according to the invention.

[0065] The invention further relates to a floor covering comprising a plurality of panels, in particular a floor panel according to the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] The present invention will now be described based on the non-limiting exemplary embodiments shown in the following drawings, in which:

[0067] Figure 1a shows a perspective view of a panel according to a first embodiment of the invention;

[0068] Figure 1b It shows that Figure 1a A cross section of the panel shown;

[0069] Figure 2 shows a cross section of a panel according to a second embodiment of the invention;

[0070] Figure 3 shows a cross section of a panel according to a third possible embodiment of the invention;

[0071] Figure 4 shows a cross section of a panel according to a fourth possible embodiment of the invention;

[0072] Figure 5a , 5b , 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, 5o show non-limiting alternative materials for the buffer layer in the panels of the present invention;

[0073] Figure 6a and 6b shows the force-displacement curves of the conventional panel and the panel of the present invention;

[0074] Figure 7 A cross section of a panel according to a fifth possible embodiment of the invention is shown.

[0075] In these drawings, the same reference numbers refer to similar or equivalent technical features or elements. DETAILED DESCRIPTION

[0076] Figure 1a A perspective view of a first embodiment of a panel is shown, in particular a floor panel 101 according to the invention. Figure 1b Shows Figure 1a A cross section of the panel 101 is shown. The panel 101 comprises a core layer 102, a decorative top layer 103 and a buffer layer 104. The buffer layer 104 is located between the core layer 102 and the decorative top layer 103. The decorative top layer 103 has the advantage of rigidity properties. In the embodiment shown, the thickness Td of the decorative top layer 103 is less than the thickness Tc of the buffer layer 104. The thickness Tu of the core layer is greater than the thicknesses Td and Tc of the decorative top layer 103 and the buffer layer 104. The core layer 102 comprises two pairs of opposite edges. In the embodiment shown, the first pair of opposite edges are provided with interconnecting connection parts 108a, 108b for connecting adjacent panels 101.

[0077] Figure 2 A cross section of a second possible embodiment of a panel, in particular a floor panel 201 according to the invention, is shown. The panel 201 comprises a core layer 202, a top layer 203 and a buffer layer 204. The top layer 203 is a particularly decorative top layer. The buffer layer 204 has a porous structure comprising struts and / or hole walls, which struts and / or hole walls comprise a plurality of folding points F. The folding points F are located at the same height within the buffer layer 204 indicated by the dashed lines 210. In the embodiment shown, the upper surface of the core layer 202 comprises a plurality of cavities 206, which are present in a predetermined pattern for dispersing impact forces and incoming sound waves. The panel 201 optionally comprises a backing layer 207.

[0078] Figure 3 A cross section of a third possible embodiment of a panel, in particular a floor panel 301 according to the invention, is shown. The panel 301 comprises a core layer 302, a decorative top layer 303 and two buffer layers 304a, 304b, wherein each buffer layer 304a, 304b comprises a pore structure. In the embodiment shown, the first buffer layer 304a is more compressible than the second buffer layer 304b. The panel 301 further comprises a backing layer 307. The decorative top layer 303 is connected to the buffer layer 304 via a plurality of connection points 309.

[0079] Figure 4A cross section of a fourth possible embodiment of a panel, in particular a floor panel 401 according to the present invention is shown. The panel 401 comprises a core layer 402, a decorative top layer 403 and a buffer layer 404. The upper surface of the core layer 402 comprises a plurality of cavities 406, which are present in a predetermined pattern. The buffer layer 404 comprises an upper buffer layer 404a and a lower buffer layer 404b. In one embodiment, the upper buffer layer 404a comprises a different material than the lower buffer layer 404b, or in some cases, the upper buffer layer 404a and the lower buffer layer 404b comprise the same material to achieve the desired effect of the present invention.

[0080] Figure 5a , 5b and 5c show non-limiting alternative materials for a panel buffer layer, in particular a floor panel according to the invention. Figure 5a One embodiment is shown in which the cushioning layer material comprises a three-dimensional structural foam layer 50a. Figure 5b The buffer layer material 50b is shown to include a honeycomb structure, which can effectively absorb impact force and play the role of a buffer layer. The honeycomb structure specifically includes a hollow vertical structure unit, such as a cylindrical honeycomb unit. Figure 5b The structural ratio Figure 5a The foam layer 50a in the embodiment is much harder. Figure 5c The cushioning material 50c is shown to comprise an ethylene vinyl acetate (EVA) layer 50c. This is, for example, a closed cell foam such as expanded rubber or foamed rubber, or any other filler used for cushioning, particularly in sports flooring. Figure 5d~5f A panel 501 according to the invention is shown, comprising buffer layers 504 , wherein each buffer layer 504 comprises a different buffer material 50 . Figure 5d An embodiment is shown in which the buffer layer material 50d includes a Voronoi-tesselated structure 50d. The Voronoi-tesselated structure 50d contains irregular pore boundaries and voids configured to optimize energy dissipation or impact resistance during impact or deformation. A detailed view thereof is shown in the figure. Figure 5e An embodiment is shown in which the cushioning layer material 50e comprises a buckling-oriented honeycomb structure that exhibits significant vertical energy dissipation capabilities while maintaining high lateral strength when the structure deforms and folds during buckling, or when the structure deforms axially due to out-of-plane compressive impact forces. Figure 5f Another embodiment of a cushioning material 50f having a buckling-oriented honeycomb structure is shown. Figure 5g Another embodiment of a panel 501 comprising a buffer layer of the present invention is shown. Figure 5h~5oA series of non-limiting cushioning materials 50h-50o are shown that may be applied to a cushioning layer according to the present invention. Figure 5h~5k Shown is a 2.5-dimensional constructed material. Figures 5l to 5o Shown are 3-dimensional constructed materials.

[0081] Figure 6a The state of the art of a conventional panel 10 is shown, which comprises a layer of vertically deformable structure 61a, such as vertically arranged hole walls, which is arranged below a flexible top layer 60a. Figure 6a The performance of conventional paneling when subjected to impact forces is further shown. As can be seen from the figure, the kinetic energy from the impact of a falling object is only absorbed at the point of impact and dissipated over a small surface area in a relatively short period of time. In addition, since the vertical structure of the material is aligned along the impact force, inertial effects occur from the vertical structure mentioned above. It can be concluded that this conventional paneling is not particularly suitable for absorbing impact forces. Figure 6b An embodiment of a panel 601 according to the present invention is shown, which comprises at least one buffer layer 61b, the buffer layer 61b being composed of a deformable structure (such as a Figure 5a-5o ) is formed and is arranged below the semi-rigid top layer 60b. As shown in the figure, the panel of the present invention exhibits volume compression, in which the top layer and the buffer layer deform or compress in a manner that allows the energy to be optimally distributed within the top layer and the buffer layer during the impact. During this volume compression process, the top layer first gradually dissipates the kinetic energy generated by the impact over a large area, and then transfers it to the buffer layer, converting the energy into internal energy in the structure of the buffer layer. The internal energy is then gradually released or absorbed, thereby significantly reducing the peak force during the impact. Because the energy is dissipated over a larger area and for a longer time, the energy transferred back to the faller or object is effectively reduced, thereby minimizing the risk of damage or injury.

[0082] Figure 7 A cross section of a panel 701 of a possible embodiment is shown, in particular a floor panel 701 according to the present invention. The panel 701 comprises a decorative top layer 702, a Voronoi pattern 3D cushioning layer 703 with decreasing density, a buckling oriented hexagonal 2.5D cushioning layer 704 and a shock absorbing backing layer 705. The density gradient of the Voronoi pattern 3D cushioning layer allows to optimally distribute out-of-plane or axial impact forces applied to the top surface. Furthermore, due to its anisotropic properties, the buckling oriented hexagonal 2.5D cushioning layer is particularly suitable for use as a core layer of a floor panel, and can even be provided with an interlocking mechanism on at least one of its sides.

[0083] Obviously, the present invention is not limited to the exemplary embodiments illustrated and described herein. Rather, many variations are possible within the scope of the appended claims. These variations are obvious to those skilled in the art. In this case, it is conceivable that different inventive concepts and / or technical measures of the above-mentioned variant embodiments are combined in whole or in part without departing from the inventive concept described in the appended claims.

[0084] The verb "to comprise" and its conjugations as used in this patent publication are understood to mean not only "to include", but are also understood to mean the phrases "including", "consisting essentially of", "formed of", and their conjugations.

Claims

1. A floor, wall, ceiling or building panel, characterized in that The panel includes: at least one core layer; at least one top layer, in particular at least one decorative top layer; and at least one buffer layer located between the at least one core layer and the at least one top layer; wherein the at least one buffer layer includes at least one pore structure, in particular at least one porous structure; wherein, according to the EN 310 standard, the elastic modulus of the at least one top layer is at least 1800 MPa, and wherein, according to the ASTM F137 standard, the at least one top layer has a flexibility of 50 mm to 350 mm in a mandrel test.

2. The panel according to claim 1, wherein The at least one buffer layer includes at least one porous structure selected from the group consisting of a hexagonal structure, a honeycomb structure, a double-wall structure, a corrugated structure, a foamed structure, a grid structure, or any combination thereof.

3. The panel according to claim 1 or 2, wherein: The at least one buffer layer includes at least one porous structure, the at least one porous structure comprising a 2.5-dimensional constructed material, preferably a 2.5-dimensional continuous lattice configuration formed by n folding points and p pore walls repeating at least once on at least one axis, and / or wherein the at least one porous structure comprises a 3-dimensional constructed material, preferably a 3-dimensional lattice configuration formed by n nodes and p struts repeating at least once on at least 2 axes, preferably wherein at least a portion of the struts and / or the pore walls include at least one folding point.

4. The panel according to claim 3, wherein The 2.5-dimensional constructed material and / or the 3-dimensional constructed material is buckling-oriented, bending-dominated, and / or has a Maxwell number ≤ 0, preferably ≤ -2, more preferably ≤ -4.

5. The panel according to any one of claims 3 to 4, wherein: The 2.5-dimensional constructed material and / or the 3-dimensional constructed material has a threshold-activated constant force response characteristic to axial force, the 2.5-dimensional constructed material and / or the 3-dimensional constructed material including elastic deformation in a first time period, a yield point Fyield, plastic deformation in a second time period, densification deformation in a third time period, and Fmax, where Fyield < Fmax, preferably, wherein the 2.5-dimensional constructed material and / or the 3-dimensional constructed material is selected from the group consisting of a hexagonal grid structure, an origami structure, a folded structure, and / or a five-mode metamaterial.

6. A panel according to any one of the preceding claims, wherein The at least one buffer layer includes at least one pore structure, the at least one pore structure including a gradient structure, in particular including a gradient discrete structure, a gradient increasing structure, and / or a gradient decreasing structure defined in the thickness of the buffer layer.

7. A panel according to any one of the preceding claims, wherein The at least one buffer layer includes at least one anisotropic material.

8. A panel according to any one of the preceding claims, wherein The panel includes a plurality of buffer layers, each buffer layer including at least one pore structure, in particular including at least one porous structure, and / or wherein the compressibility of the at least one buffer layer is greater than the compressibility of at least another buffer layer.

9. A panel according to any one of the preceding claims, wherein The thickness of the at least one buffer layer is in the range of 3 to 8 mm.

10. A panel according to any one of the preceding claims, wherein The Shore D hardness of the at least one top layer is in the range of 60 to 90, more preferably in the range of 70 to 85.

11. A panel according to any one of the preceding claims, wherein According to the EN 310 standard, the at least one top layer has an elastic modulus of at most 5500 MPa and / or a thickness in the range of 0.05 to 5 mm, preferably in the range of 1 to 4.5 mm, more preferably in the range of 1.5 to 4 mm.

12. A panel according to any one of the preceding claims, wherein The panels may have a G-max of less than 120G and / or a HIC of less than 800 when tested according to ASTM F1292 standard.

13. A panel according to any one of the preceding claims, wherein The at least one top layer comprises at least one polymer material and preferably comprises at least one mineral filler, multiple layers of resin impregnated paper or at least one cellulose based material selected from at least one wood veneer and / or at least one bamboo veneer.

14. A panel according to any one of the preceding claims, wherein The at least one panel has an average density of at least 1000 kg / m 3 , preferably at least 1200 kg / m 3 , more preferably at least 1400 kg / m 3 .

15. A panel according to any one of the preceding claims, wherein The panels include at least one pair of opposite sides, and interconnecting connection parts are arranged on the at least one pair of opposite sides for interconnecting adjacent panels.

16. A panel according to any one of the preceding claims, wherein The at least one core layer is a composite core layer comprising at least 60% by weight of at least one mineral material and at least one binder.

17. A panel according to any one of the preceding claims, wherein The density of the at least one core layer is at least 1200 kg / m 3 , preferably at least 1400 kg / m 3 .

18. A panel according to any one of the preceding claims, wherein According to the EN 310 standard, the at least one core layer has a stiffness of 3500 MPa or less, preferably 2000 MPa or less, and / or a thickness in the range of 2 to 20 mm.

19. A panel according to any one of the preceding claims, wherein At least a portion of the upper surface of the at least one core layer and / or at least a portion of the lower surface of the at least one core layer comprises a plurality of cavities.

20. A panel according to any one of the preceding claims, wherein The panel comprises at least one reinforcement layer, wherein the at least one reinforcement layer is located between the at least one top layer and the at least one buffer layer.

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