DE29715241U1 - plate - Google Patents

Description

plate

The invention relates to a plate according to the preamble of claim 1.

A variety of panels or panel bodies are known from practice, which form a horizontal storage or work surface for objects. Table tops or kitchen worktops are very common. Also well known are window sill panels, laboratory table tops, but also tiles with which floors or walls can be covered, or panels as shelving elements.

In practice, it is known to use processed solid wood or stone as a worktop, for example for kitchen tables. Stone worktops in particular are very popular because of the low tendency to damage their surface. However, they are expensive to buy and process and have an extremely high density and therefore a very high weight. In addition, a uniform texture of natural materials can never be achieved. If a work surface is made up of several levels, clearly visible joints remain between the panels.

For weight and cost reasons, instead of solid wood panels, so-called veneered panels are used, in which a thin veneer sheet made of plastic or wood is glued onto a cheaply available compressed wood panel ("chipboard", HPL panel), which looks similar to

Solid wood appears. However, these veneered panels do not allow adequate screwing or the use of other fixing agents, as the tight threads of the screws are not held and instead cause the neighboring compressed wood particles to crumble. In addition, the veneered wood panels are still quite heavy, whereas the thin veneer layer is susceptible to damage. Finally, the veneers for covering the corner areas of the compressed wood must be glued on from several pieces, each of which must be cut to size, as the veneer material does not allow bending at a right angle. This creates unsightly gaps on the edges that are subject to high levels of stress, which greatly impair the overall aesthetic impression compared to solid material. In addition, such joints are not waterproof, so that the compressed wood underneath the veneer begins to move when it absorbs water.

Instead of compressed wood, substrates made of medium-density fiberboard (MDF) have been suggested, which allow for screwing more easily than compressed wood. However, the MDF boards are heavier and more expensive to buy.

Panels are also known from practice that consist of a plastic cladding sheet to which a frame made of squared timber is glued. Another narrow cladding strip made of the same plastic is then placed perpendicular to the cladding sheet and the resulting gap is eliminated by applying plastic that has not yet hardened, so that a seamless cladding element is produced. A disadvantage of this known panel is that the wood and the plastic material expand differently depending on temperature and weather conditions, so that a gap is generally left between the cladding strip and the squared timber, which must be filled with a joint filler, e.g. a silicone compound, so that the support of the cladding strip is only minimal. This is also critical because a weight load from the side strip acts with great leverage on the seam between the cladding sheet and the cladding strip. Another disadvantage of this well-known panel is that the squared timbers and the cladding parts have to be cut to the final size in separate operations. It must also be taken into account that in order to screw the panel onto a base, the screws must also be attached to the squared timbers, or additional squared timbers must be used for this purpose. The manual work is generally carried out in a carpenter's workshop, which is very time-consuming and requires a lot of logistics, simply because of the need to stock up on wood. Although it is possible to use a suitable material for

the cladding parts can also be connected without gaps, but when several parts are put together, a new substructure must always be made. Clean connection and bracing, as with chipboard, is not possible. The squared timbers used are heavy and generally do not allow the panel to be fully supported, so that a hollow sound is produced when touched in large areas of the panel. The feel of such plastic panels is also that of plastic, even if they are elegantly presented.

For laboratory tables that are required to be acid-resistant, it has been suggested that a base be covered with tiles and the relatively wide gaps between adjacent tiles be sealed with a joint filler. The edges of the base and the corner areas are covered with angle or corner tiles so that the edges are always covered. Covering a large number of tiles in different shapes makes the known laboratory tables expensive and heavy.

In addition to solid stones, multi-folded metal sheets have also been suggested for window sills. These have a hollow and cheap acoustic when touched. They are also susceptible to distortion and, for manufacturing reasons, there is always a visually disturbing gap in the corners. Most of the metal sheets are also a few millimeters thick, otherwise the hollow plate becomes too heavy. Finally, these metal sheets can only be reworked using complex welding or similar. In addition, metal elements tend to form condensation on their invisible inside and thus to corrosion. The surface of such metal sheets is not suitable for storing heavy or large objects because it bends.

In the past, it has been suggested that rigid elements made of aluminum, for example, be filled with polyurethane as a thermal insulation element, resulting in a laminated rigid foam board. Laminated rigid foam boards cannot generally be manufactured without a gap for excess polyurethane to escape. Furthermore, elements with small gradations, e.g. raised edge zones, cannot be processed mechanically. Finally, when the known thermal insulation elements are attached to a house facade or similar, they are usually covered with a cladding, e.g. made of natural stone, as they are not very aesthetically pleasing when unclad.

The object of the invention is to create a plate according to the preamble of claim 1 which is stable and yet has a low weight.

This object is achieved according to the characterizing part of claim 1.

In contrast to veneer coverings, the cladding element is designed as a rigid and one-piece, with its underside being open or hollow with a recess. To increase rigidity, it can be provided that webs on the back of the cladding element pass through the recess. The cladding element is therefore advantageously a base that can be used without any underlay, e.g. as a so-called "repa plate". The cladding element also already has the essential aesthetic and physical properties of a finished plate.

In order to produce a panel according to the invention from the cladding element, the recess is lined with a lining element on the bottom side. Advantageously, the entire underside of the cladding element is continuously supported, but it is also possible to only provide the lining in preferred areas, e.g. in the area of side edges. The thickness of the lining element is at least two thirds of the thickness of the resulting panel, which, after being filled with the lining element, emits a rich sound when tapped on the surface. The lining element is inexpensive to manufacture and lightweight compared to the expensive material of the cladding element, whose "noble" appearance serves as a sales argument, so that at least two fifths and advantageously more than half of the panel weight in the lined areas is due to the weight of the cladding element. The density of the cladding element is advantageously at least three times higher than the average density of the lining element.

The cladding element preferably has an at least partially circumferential edge region, preferably formed in one piece with the work surface and projecting downwards essentially at a right angle from the latter, which laterally delimits a recess for the underlay element. The side edge and underside of the underlay element are flush, so that a finished panel according to the invention acts like a solid element in terms of the volume it takes up. This means that the panel according to the invention can be transported easily and in a volume-saving manner, and is also easy to stack.

The cladding element is preferably a part made from one piece, e.g. by machining a block of stone or wood, or preferably a piece made from one piece by primary shaping, e.g. by pressing, sintering or the like. It is possible that the one-piece

also by assembling several components, e.g. welding, gluing, joining or screwing. Advantageously, however, it will be a composite material that is formed by a combination of stone or sand (SiO ₂ ) on the one hand and plastic on the other. With a suitable composition or processing, such a composite can take on a very similar appearance to natural stone, which also has other desirable properties of stone slabs, in particular scratch resistance, good workability, rigidity, insensitivity. Such a composite is advantageously thin compared to the corresponding processing of a natural stone slab and can be produced with a correspondingly large recess, e.g. by applying heat in a corresponding counter-mold. Since the underside will later be covered with the underlay element, no post-processing is required for this; instead, the rough surface is particularly suitable for bonding. Optionally, it is advantageous to reinforce the composite with a glass fiber matrix to increase the rigidity of the cladding element. Such cladding elements can be produced in consistently good quality and are free of microcracks.

According to a particularly preferred variant of the invention, the material of the cladding element is repairable, i.e. the joint between two adjacent sections of two cladding elements is connected to one another by a repair process, e.g. by applying a corresponding material, e.g. a liquid plastic or resin, at least in such a way that the joint is no longer easily visible to the human eye. In particular, in the case of large panels whose appearance resembles that of a stone panel, the prestige value is particularly increased with joint-free, large-format panels, even in complicated geometric shapes.

Preferably, the underlay element is a lining made of expanded rigid foam that is cut to size according to the needs of the cladding element. Preferably, a one- or multi-part underlay element extends under the entire surface of the cladding element. It goes without saying that the underlay element can also be composed of several adjacent parts. Alternatively, however, it is possible to design the underlay element only as a frame that preferably runs along the side edges of the cladding element.

According to a particularly preferred development of the invention, the underlay element comprises several layers or plies. These are preferably layers made of the same material, e.g. a rigid foam

material such as polyurethane. The layers are expediently of different densities; on the one hand, this makes it possible to integrate extremely light layers into the underlay element and thus into the plate according to the invention, which fill the plate with a minimal increase in weight; on the other hand, it is possible to provide denser and thus more resilient layers in certain preferred layers, e.g. in the middle area of the thickness of the underlay element. The denser layers, which preferably have a density between 250 grams per liter and 750 grams per liter, and even up to 1800 grams per liter in the case of particularly thin layers, withstand higher tensile loads, such as can occur when two plates according to the invention are braced against one another using known turnbuckles.

Unlike wood materials, polyurethane does not "burn" the diamond dust that is typically used in saws for materials containing stone. Thus, according to another aspect of the invention, a stone-containing board is advantageously provided that can be sawn with a diamond-tipped tool.

In addition to a suitable paper lamination sheet, the underlay element preferably comprises three layers of approximately the same thickness, of which the middle layer has a density that is approximately 2 times higher than the two neighboring layers. Alternatively, underlay elements with two, four, five or even more layers can also be considered. It is also possible for the denser layer to be arranged eccentrically in a stack of several layers. In general, the layer with the higher density can be narrower, within preferred limits, the greater its density. Advantageously, the layers run parallel to the working surface of the cladding element, and thus transversely to its edge.

The panel according to the invention is preferably produced by gluing the underlay element to the underside of the cladding element. Polyurethane is advantageously used as the adhesive, especially if an upper layer of the underlay element is also made of polyurethane as this ensures good penetration of the adhesive into the depth of this layer. In addition, if present, the side strips of the cladding element are preferably also glued to the underlay element. When using an underlay material made of polyurethane, it is not necessary to leave a gap between the side strip and the underlay element, which allows play to be compensated for by a filling material. Rather, the combination according to the invention enables the side strips to be attached directly.

bar to the underlay element, whereby full-surface support of the side bar ensures optimal transfer of loads.

The plate according to the invention or parts thereof can be connected to other plates or parts thereof in a simple manner by providing suitable connecting means in the underlay element. The plate is characterized by very good processability. It is particularly advantageous to use the connecting means used for wood or veneer goods in the manner known to the expert from the known plates. For this purpose, corresponding recesses for connecting elements, so-called "lamellos", e.g. made of wood, can be provided in the middle of the underlay element on a cut edge of a plate using the same tools that are also used to process known plates made of veneered compressed wood. Furthermore, a recess suitable for receiving a metal turnbuckle can be made in the base of the underlay element, which preferably passes through several layers of a multi-layer underlay element and in which the turnbuckle is supported in particular against the denser layer in the manner of a shoulder. Several panels according to the invention can thus also be put together to form corner combinations or very long units, which is only possible with great effort with other heavy materials. It is also possible to screw in screws through the underlay element and preferably essentially perpendicular to the course of the layers or to glue the underside of the panel according to the invention to the lamination strip or a lower layer with a base cabinet or another element that forms a type of base in order to use the panel according to the invention for the production of parts according to the invention such as tables, kitchen work surfaces, laboratory tables, window sills or other storage or work surfaces.

The panel according to the invention is characterized by a lightness that is unusual for its thickness and its cladding element material, which makes it possible to pick, transport and assemble even larger dimensions, e.g. approx. 1.50 m x 2.80 m, as they occur in typical applications, without lifting equipment. The average weight of a panel according to the invention is only approx. 17 to 20 kg/m ² despite an extremely resilient closed surface of the one-piece cladding element. The good thermal insulation properties make the panel according to the invention also suitable as decorative cladding for house facades and other cladding.

If, for example, a worktop is made to measure from a panel of the above-mentioned size, this can be done by first cutting several panels according to the invention to size so that they correspond to the dimensions of the worktop. Then, preferably, recesses and cutouts for connecting and clamping devices are worked into the lining material and the panels are fixed to one another. Then, advantageously, the joint in the cladding element is eliminated by applying a resin component. If necessary, it is possible to add side strips to surround the worktop made to measure with an edge all the way around.

As a result, it is possible to produce a panel cost-effectively whose appearance, sound and feel correspond to those of a stone panel, whose repairability, weight and crack-free quality correspond to a plastic panel, and whose processability and assembly correspond to a wood veneer panel.

Further advantageous embodiments of the invention can be found in the following description and the subclaims.

The invention is explained in more detail below using embodiments shown in the accompanying drawings.

Fig. 1 is a plan view of a plate according to the invention with an incorporated opening.

Fig. 2 is a section along the line H-II through the plate of Fig. 1.

Fig. 3 is a section along the line III-III through the plate of Fig. 1.

Fig. 4 is a bottom view of two panels according to the invention which are to be joined together.

Fig. 5 is a cross-section along the line V-V through one of the panels and through a side strip to be attached to the panel from Fig. 4.

Figures 1 to 3 show an embodiment of a panel 10 according to the invention, which is formed from a cladding element 11 and a lining element 12. The cladding element 11 forms a flat outer (upper) work surface 11a and, at a substantially right angle to this, a side strip 11b which is integral with the work surface. The thickness of the work surface 11a is approximately 5 mm in the central area and approximately 8 mm in a surrounding edge area that is approximately 20 mm wide. The side strip 11b is approximately 8 mm thick and forms a right angle on the thicker edge area of the work surface 11a. The height of the side strip 11b (internal dimension) is approximately 32 mm, so that the total thickness of the panel 10 in the edge area of the work surface 11a is approximately 40 mm (external dimension) and in the central area of the work surface 11a is approximately 40 mm (external dimension).

approx. 37 mm. It is possible to change these dimensions by a few millimeters. The cladding element is preferably free of metallic components and thus rust-free. An opening 20 is incorporated into the plate 10, which is discussed further below.

In the present embodiment, the cladding element 10 consists of a composite material which was shaped by primary molding. The composite material is sold in practice under the brand name askilan® and comprises, among other things, a proportion of between 20% and 80% granite, which is produced, for example, as granite sand (SiO ₂ ) with other plastics to form a moldable, one-piece, rigid and hard material composite which is thermally hardened by the addition of heat. However, it is also possible to use processed natural stone or solid wood. It goes without saying that the material of the cladding element advantageously has essentially the properties of a solid stone slab, i.e. temperature resistance, stability, resistance to cuts by kitchen utensils, resistance to impact, etc. The cladding element has a high density of approx. 1800 grams/liter, which results in an average weight of approx. 9 kg/m ^2. The weight can be between 6.5 and 15 kg/m ² , depending in particular on the proportion of granite and with a corresponding thickness.

The geometric shape of the working surface 11a of the plate 10 can be freely selected. In the present embodiment, it has a substantially rectangular outline. However, it is also possible to form the plate 10 in the shape of a disc or a disk, so that the side strip 11b then essentially forms a hollow cylinder wall. The plate 10 preferably has a closed, circumferential side strip 11b; however, it is possible for a section of a plate to be formed with a side strip 11b at only one or two, preferably opposite, lateral ends, e.g. when a plate is cut out of a larger plate 10. The plate 10 can also be shaped as an angle piece, polyhedron, oval, etc. In particular, a plate can also consist of two assembled, previously independent plates.

In the present embodiment, the underlay element 11 comprises three layers 13, 14 and 15 made of polyurethane foam, which are attached to one another in pairs, as well as a lower lamination layer 16 made of paper. The (upper) layer 13 of the underlay element 12 is glued to the cladding element 11 on its inner surface. The bonding is carried out by means of a polyurethane sprayed or applied to the cladding element. By reaction

With the polyurethane foam of layer 13, the polyurethane foam layer 13 adheres to the cladding element 11, whereby the bonding forces are very high. Polyurethane adhesive is preferably also applied between the inside of the side strips 11b and the underlay element 12 to create an adhesive connection.

In contrast to a wood veneer material, however, the cladding element 11 is manufactured as a one-piece and rigid part in a first step in accordance with the required external dimensions, and the - already foamed - underlay material 12 is then attached to the cladding element 11. In other words: the cladding element 11 is the substrate to which the underlay material 12 is attached.

In the present embodiment, the upper layer 13 and the lower layer 15 consist of the same material, namely polyurethane (PU) foam, and also have the same thickness of approx. 10 mm, see Fig. 2. The material of the layers 13, 15 is porous and has an extremely low density of approx. 200 grams per liter (g/l).

The middle layer 14 arranged between the two layers 13, 15 is approximately 11.5 mm thick and is essentially as thick as the two neighboring layers 13, 15. The middle layer 14 also consists of a polyurethane layer made of polyurethane recyclate, but with a density of approximately 400 g/l, i.e. approximately 2 times higher than that of the layers 13, 15. In addition, the middle layer 14 advantageously contains deposits 14a, which are thus recycled, or is inexpensively designed as a mat made of pressed residues (so-called Puronit®).

The lamination layer 16 consists of melamine resin-impregnated and varnished paper with a maximum thickness of 0.5 mm, which is essentially flush with the lower end of the side strips 11b. The lamination layer 16 is washable and provides protection against water penetration. The lamination layer 16 advantageously also protects the otherwise exposed layer 15 from undesirable mechanical stress and thus prevents the PU foam from gradually "crumbling" or the undesirable deposition of water in the pores. Instead of a paper layer, a plastic layer or another suitable film can be used.

The layers 13 and 15 on the one hand and 14 on the other hand form an optimized combination with regard to the workability of the lining element 12. The layers fulfill different functions, as will be explained below. First of all, the lining element 12 serves to

to give the quasi-hollow cladding element 11 a pleasant, full acoustic sound when touched. At the same time, however, layers 13 and 15 are extremely light, around 2.0 kg/m ² ; taking into account the thickness of layers 13, 15 of around 10 mm, this is significantly less than the weight of solid wood or stone, and still significantly less than the weight of MDF or HPL boards of a corresponding thickness. The same applies - to a lesser extent - to layer 14; it weighs around 4.6 kg/m ² and is therefore also less than the weight of HPL boards of a corresponding thickness. The underlay element 12 therefore has a thickness of around 32 mm and weighs only around 8.6 kg/m ² , and is therefore still less than the weight of cladding element 11, even though it is around 6x thicker. Overall, the panel 10 weighs only about 17.6 kg/m ² and thus, despite its rigid and stress-resistant cladding element forming the outer surface, it weighs less than solid wood or stone panels. Finally, the arrangement of the denser layer 14 in the middle area of the underlay element also results in a good screw strength of about 100 kg when the panel is screwed onto a substructure, for example.

As can be seen in Fig. 1, a substantially square opening 20 is set into the plate 10, the peripheral edge 21 of which has a recess of approximately 2 mm relative to the surface 11a. A sink or the like can be set into this recess in a form-fitting manner such that its upper edge is flush with the work surface 11a. The area of the opening is also free of underlay material, as can be seen in Fig. 3.

For large-scale production, it is advisable to ensure that the same lining material is always used, especially in terms of thickness, even when the dimensions are very different. In this way, it is possible to deliver the lining material 12 in mats that are cut to size and then glued, preferably over the entire surface, to the corresponding cladding elements. The lining material mats can be transported particularly economically due to their low weight, their ability to be stacked on pallets and the fact that the shape of the mats allows for full use of the volume.

It is understood that in addition to layers 13-15, further layers running parallel to these can also be provided. It would also be possible to manage with just two layers, and it is also possible to provide the middle layer 14 as a slightly less thick layer, and to fill the remaining gap or gaps either by increasing the thickness of the

Layers 13 or 15 or by inserting a further layer, e.g. made of polyurethane of appropriate thickness, preferably very low density.

The use of polyurethane is advantageous because this material can be processed with both wood processing tools (steel and hard metal saws) and stone processing tools (diamond-studded saws, cutting ceramics) without excessive wear on the tool. In this respect, polyurethane is superior to wood as a lining material for stone-containing cladding elements. Preferably, wood-free materials are therefore used for the manufacture of the lining element 12 or the plate 10 according to the invention, since this enables them to be processed with diamond-dust-coated saws without excessive wear. Furthermore, the use of polyurethane enables good adaptation to the thermal expansion of cladding element materials such as stone, wood or plastic, so that when the plate 10 is subjected to thermal stress, thermally induced internal stresses in the plate are avoided, since the difference in thermal expansion is small. The use of the same material for all three layers 13, 14 and 15, here: polyurethane, aims in the same direction. By bonding on the underside of the surface 11a and on the inside of the edge 11b, any dimensional tolerances caused by production are compensated for by the adhesive, which reacts with the lining material.

Particularly preferred designs emerge from the dimensions in the drawings.

With reference to Figures 4 and 5, a further embodiment of a plate 10 according to the invention will now be explained in more detail. The same reference numerals as in the previous embodiment designate the same parts with the same properties.

From Figs. 4 and 5, another particular advantage of the plate 10 according to the invention is apparent, which consists in the fact that the underlay element 12 can be processed like light wood or compressed wood, for example by sawing, milling or the like. The middle layer 14 can withstand tensile forces of up to 90 kg, recesses 31 for the insertion of connectors 32, so-called "Lamello", can be produced in a dimensionally stable manner using tools suitable for wood processing. The same applies to recesses 33 in the form of a cylinder with a channel leading out of the cylinder over the entire height of the cylinder wall (see Fig. 4), in which turnbuckles 34 can be arranged, with the help of which two plates 10 can be locked together. The turnbuckles 34 are supported on the shoulders of the cylinder wall of the recess.

tion 33 and can generate strong axial tensile forces by tightening a threaded unit. Screws and other fixing means can also be inserted into the underlay element 12 - both perpendicularly and parallel to the layer direction of the layers 13 - 15. These fixing means preferably penetrate the denser layer 14, which can withstand particularly high tensile loads due to its higher density. The layer 14 gives the entire underlay element 12 a special strength that justifies its higher weight. Due to the particularly advantageous arrangement in the middle of the underlay element 12, between the two lighter layers 13 and 15, the layer 14 gives the underlay element 12 sufficient strength in all stress directions, but without having to have a correspondingly large thickness and thus a correspondingly high weight.

Advantageously, the layer 14 is thicker than the thickness of the known connectors 32 (approx. 4 mm), so that when a recess 31 is provided in the underlay element 12, this preferably does not fall into the area between two adjacent layers. Furthermore, the thickness of the layer 14 is narrower than the active surface of a known turnbuckle 34, so that part of the tensile load is also transferred to the layers 13, 15. Since this type of connection is known to the master installer who installs the kitchen from the use of wood materials, no different instructions are required. The plate 10 according to the invention can therefore easily replace plates made of compressed wood.

Preferably, the joint between the cladding elements of two assembled panels 10, 10' according to the invention is then eliminated with a plastic material such as resin or the like, which is also a component of the cladding element material. The good processability and configurability of the panel according to the invention and its low weight, its rich acoustics as well as its elegant appearance and feel, also due to the repairability and the joint-free nature of the surface, are tangible advantages.

In Fig. 5, on the left, a side strip 11b separated from a cladding element by sawing can be seen in a sectional view. The area of the separated side strip 11b that corresponds to the thickness of the work surface 11a (i.e. approx. 5 x 12 mm) has been milled away. This makes it possible to attach the side strip in the manner of a nose over a sawn-off edge of a panel 10 according to the invention and to glue it in place, which again creates a preferred panel with a side edge.

A particularly preferred manufacturing process for a plate 10 according to the invention is now briefly explained below. The plate 10 is intended as a kitchen worktop.

To produce a panel 10 according to the invention, a cladding element 11 with a working surface 11a is first produced by primary molding. The cladding element 11 is preferably a composite material made of at least one thermosetting plastic and a quantity of granite sand (SiO ₂ ) as well as other components. The cladding element preferably also comprises side strips 11b during production.

In order to obtain a surface in the manner of a polished stone surface, a grinding or polishing step is carried out following the primary shaping step, in which a fine machining of the external surfaces of the cladding element 11 and in particular the working surface 11a and the external side strips 11b is carried out. The grinding or polishing step advantageously allows a better and more natural look and feel, or one that is more similar to the natural look of solid stone. In contrast to an unprocessed surface, the processed surface can be repaired without leaving any emery marks. This almost traceless repairability is a significant advantage of the resulting panel according to the invention.

If desired, a square piece of the work surface 11a can be cut out afterwards, into which a sink can later be inserted. In this case, the edge 21 of the cut-out area 20 is preferably recessed by approx. 2 mm by removal, so that the edge of the sink forms almost a plane with the work surface 11a of the cladding element.

A piece of filling material 12 adapted to the size of the cavity of the cladding element 11 is then cut out of a mat made of three layers 13-15 that are attached to one another and have a paper-laminated underside. The size of the mat preferably already matches the size of the recess in the cladding element 11. The filling material preferably consists of three layers of polyurethane of different densities. It goes without saying that the open areas, e.g. for a sink, are also cut out.

An adhesive, preferably liquid polyurethane, is then applied to the back of the working surface 11a of the cladding element 11. The underlay element 12, which may have been cut to size, is then placed on the adhesive layer and pressed against the back, if necessary with the help of suitable

Tools such as clamps, etc. As soon as the adhesive has hardened, there is a closed connection between the cladding element 11 and the underlay element 12. A panel 10 according to the invention is ready.

If this has not already been done, an opening 20 for a sink or the like can still be cut out of the plate 10, whereby the cladding element 11 and the underlay element 12 are then cut out at the same time, e.g. by sawing.

It is also possible to saw off parts of the protruding plate 10 and to let in clamping means 34, alignment means such as connectors 32 and the like as well as associated recesses 31 or cutouts 33 of the type already described above into the underlay material 12 using a sawing or milling tool, in order to then reassemble them with parts of another plate 10', e.g. at an angle, to form a new plate 100 according to the invention, e.g. a kitchen worktop combination. The connecting means arranged in the underlay elements fix the two plates 10, 10' relative to one another. It is possible to additionally glue the flanks of the respective underlay elements that touch one another. The two cladding elements are then processed in order to eliminate the joint running along the interface, e.g. by applying a resin or thermosetting, liquid plastic to the surface.

According to a particularly preferred development, it is possible to glue the side strip 11b at the end of the assembly of a panel, for example from several panels 10, 10' assembled at an angle, to cover the edges. To do this, an edge piece 11b is first sawn off from a panel 11 or panel 10. The dividing line preferably runs along the slightly thicker area of the panel, approx. 20 mm from the edge. Then the area that corresponds to the thickness of the cladding element 11 in the working area 11a (i.e. approx. 5 mm) is milled away, as is the piece of underlay material 12 if the edge was sawn off a finished panel 10. This results in a "nose" comprising the side strip 11b and the overhang of approx. 3 mm thickness protruding at right angles from it (see Fig. 2 or Fig. 5). This nose can now easily be placed on a sawn off edge of a panel 10 by gluing the underside of the overhang seamlessly to the cladding element 11, for example using resin, and gluing the edge 11b to the underlay element 12 using e.g. polyurethane glue. The side cladding is seamless, and due to the large adhesive surface, without

The silicone intermediate layer ensures good transfer of forces, which gives the panel produced according to the invention excellent robustness. It goes without saying that the process according to the invention also enables the production of panels with very complicated geometries. Furthermore, very large panels can be produced with consistent quality, which are joint-free and have a uniform appearance even when they have been assembled from several panels, which is not possible with natural stone panels, for example. Finally, it is advantageously possible to produce or rework already finished panels by re-cutting and recombining them in ever new installation dimensions, so that, for example, when a kitchen is being remodeled, the existing kitchen worktop made from a panel according to the invention can be reintegrated.

The panel according to the invention has been explained in more detail above using preferred embodiments. It goes without saying that the means which the expert can easily find from the above description to be equally effective or complementary and which serve to achieve the same purpose can also be used. For example, it is possible to change the material densities and thicknesses described above, or to change the composition of the materials. It is also possible to provide inlays in the underlay element, e.g. made of wood, or to select phenolic resin, polyethylene or polypropylene as the material for a layer of the underlay element. It is also possible, for example, to underlay only certain areas, e.g. the edge areas in the manner of a frame, instead of a continuous underlay. It is also possible to design a panel according to the invention without side strips. It is also possible to combine a panel according to the invention with other panels of a conventional design.

Claims (28)

&Ggr;: &KHgr; 17 ::. &Ggr;: &KHgr;. &Ogr; 602 GM 01 Protection claims 1. Panel with a cladding element forming at least one working surface of the panel and at least one underlay element arranged underneath, characterized, that the cladding element (11) is designed as a rigid and one-piece part with a recess on the side facing away from the work surface, wherein the cladding element (11) accounts for at least two fifths of the total weight of the panel (10), and that the underlay element (12) comprises a lining cut to fit into the recess of the cladding element (11), wherein the thickness of the underlay element (12) amounts to at least two thirds of the total thickness of the plate (10). 2. Plate according to claim 1, characterized in that the lining is formed from a rigid foam material. 3. Panel according to claim 1 or 2, characterized in that the cladding element (11) is a part produced by primary molding from a composite material. 4. Panel according to claim 3, characterized in that the cladding element (11) is pressed in a mold with the supply of heat. 5. Plate according to claim 3 or 4, characterized in that the composite material comprises a fiber reinforcement. 6. Plate according to one of claims 3 to 5, characterized in that the composite material comprises a plastics content of at least 10% by weight. 7. Plate according to one of claims 3 to 6, characterized in that the composite material comprises SiO ₂ . 8. Panel according to one of claims 1 to 7, characterized in that the cladding element (11) has edges (11a). 9. Plate according to one of claims 1 to 8, characterized in that the underlay element (12) comprises at least two layered layers (13, 14, 15). 10. Panel according to claim 9, characterized in that the layers (13, 14, 15) run parallel to the working surface of the cladding element. 11. Panel according to claim 9 or 10, characterized in that only the uppermost layer (13) of the underlay element (12) is glued to the cladding element (11). 12. Plate according to one of claims 9 to 11, characterized in that at least one of the layers (13, 15) has a density between 50 g/l and 350 g/l. 13. Plate according to one of claims 9 to 12, characterized in that at least one of the layers (14) has a higher density than the other layers (13, 15), which lies between 250 g/l and 750 g/l. 14. Plate according to claim 13, characterized in that the layer (14) with the higher density is arranged at least partially in the middle third of the underlay element (12). 15. Plate according to claim 13 or 14, characterized in that the ratio of the product of density and thickness of the layer (14) with the higher density to the sum of the products of density and thickness of the remaining layers (13, 15) is between 0.6 and 3.0. • · * &idgr; 16. Plate according to one of claims 9 to 15, characterized in that at least one of the layers (13, 14, 15) is formed from polyurethane foam. 17. Plate according to one of claims 1 to 16, characterized in that slot-shaped recesses for receiving plug-in connecting elements are provided in the underlay element (12). 18. Plate according to claim 17, characterized in that the slot-shaped recesses are located in the middle of the thickness of the underlay element (12). 19. Plate according to one of claims 1 to 18, characterized in that recesses are provided in the underlay element (11) for receiving a clamping element. 20. Plate according to claim 19, characterized in that recesses pass through at least the lower two thirds of the underlay element (11). 21. Plate according to one of the preceding claims, characterized in that the thickness of the underlay element (12) amounts to at least three quarters of the total thickness of the plate (10). 22. Panel according to one of the preceding claims, characterized in that the density of the underlay element (12) is less than a quarter of the density of the cladding element (11). 23. Panel according to one of the preceding claims, characterized in that the cladding element has a repairable appearance and feel. 24. Table, characterized by at least one horizontal plate according to one of claims 1 to 23. 25. Kitchen worktop, characterized by at least one horizontal plate according to one of claims 1 to 23. ·&KHgr; 20 .· : 26. Window sill, characterized by at least one horizontal plate according to one of claims 1 to 23. 27. Laboratory table, characterized by at least one horizontal plate according to one of claims 1 to 23. 28. Shelf, characterized by at least one horizontal plate according to one of claims 1 to 23.