CA2295816A1

CA2295816A1 - Panel-shaped material

Info

Publication number: CA2295816A1
Application number: CA002295816A
Authority: CA
Inventors: Friedrich Sen Schock; Karl Schock; Gunter Hieber
Original assignee: Individual
Current assignee: Schock GmbH
Priority date: 1997-07-26
Filing date: 1998-07-16
Publication date: 1999-02-04
Also published as: DE59810286D1; WO1999004965A1; ATE255006T1; IL134153A; KR20010022269A; CN1088427C; IL134153A0; DE19732216A1; AU8976198A; WO1999004972A1; EP0998387B1; CN1265063A; AU8976298A; JP2001510750A; EP0998387A1

Abstract

The invention relates to a panel-shaped material, for use especially as a kitchen work top, table top or such like, comprising a panel-shaped support, a covering layer joined to the panel-shaped support across the surface thereof and a covering element which is arranged along at least one side edge of said support and joined to the covering layer in a monobloc manner. To be able to produce in an economical manner a material of this kind which remains stable even in a humid environment the invention provides for the support to have a covering layer on one side only, for the covering layer and covering element to be made of a plastic material filled with an inorganic filler and for the covering layer to have a thickness ranging between 3 and 10 mm and to be joined to the support by means of a hardenable resin across its entire surface and substantially without the formation of bubbles.

Description

A panel-shaped material The invention relates to a panel-shaped material, in particular for use as kitchen worktop, table top or the like and also a method for its manufacture.
Panels for these uses are frequently known in the form of panel-shaped supports made from a wood material with a covering layer applied thereto to form a useful surface and with a covering element which is disposed along at least one side edge of the support and is in one piece with the covering layer.
The most common are surface and working surface panels, which are formed from a backing plate as the support layer and a thin covering layer (thickness < 1 mm), for which decorative high-pressure laminated sheets (HPL) are used, as well as for a covering element at the side edges. The thin covering layer is susceptible to damage ~~y pointed or sharp objects. If the surface is damaged, moisture penetrates into the support layer which is not moisture-resistant. This swells up and raises the thin covering layer. The same problem occurs with joints which are produced when two panels are joined to one another, e.g. in the case of a kitchen worktop. If the sealing is not performed carefully, moisture can again ~>enetrate into the support layer and make it swell. Hot pans which are placed on the surface also result in damage to the thin layer with the consequences described above .
I_n addition panel-shaped materials having a covering 1_ayer made from so-called solid surface materials, such as e.g. Corian~ were already used, in which the thickness of the covering layer is approx. 13 mm, to ensure when used as a kitchen worktop that hot pots placed on the worktop do not result in the covering layer being damaged or even destroyed. The processing of these materials requires great care: cutouts for kitchen sinks or hobs have to be milled out and the milled edges have to be cut-off to avoid any stress concentrations, which may result in cracking in particular in the radial region of the cutout.
On account of the relatively great thickness of the covering layer, in the case of Corian~ materials no panel-shaped support but instead a batten substructure is frequently used. In the case of Corian~ materials the covering elements of the side edges are produced by glueing covering sections, so that there are joints in the impact region. These joints are susceptible to dirt and thus less desirable in the kitchen and bathroom region.
Since the frame substructure and also the side edges have to be manually applied, the processing of these materials requires high manual expenditure and thus high requirement of staff and results in a highly priced product.
Furthermore, the Corian» materials demand a relatively high use of highly priced filled plastic materials. To alleviate warping problems, the Corian~ materials have to be connected to the support with an elastic layer, in particular silicone adhesives.

Moreover, so-called sandwich panels are known, for example from DE-A-38 17 224, in which the panel-shaped backing is disposed between two covering layers. One of the covering layers in this case forms the useful surface, while the other covering layer serves as a so-called counteracting device, to avoid warping of the panel. The layer thicknesses mentioned in this document lie in the range of from 3 to 7 mm. The production of such sandwich panels is relatively expensive and requires a relative high use of materials in relation to the plastic materials that are used to form the covering layer.
Known from DE-U 91 00 507 are panel-shaped products in which a support member is surrounded on all sides by a layer of plastic material.
EP-A 0 310 935 instructs that a panel-shaped material that can be used as a kitchen worktop and with a sandwich structure can be produced in that first of all the covering layer with borders is produced and by laying a lower layer on the borders a cavity that can be filled with a foaming plastic compound is formed. The lower layer, in conjunction with the intermediate layer of foam and the covering layer, helps to determine the mechanical properties of the sandwich panel.
The object of the present invention is to propose a panel-shaped material which can be produced at a favourable price and which is also stable in a humid environment.

This object is achieved in accordance with the invention with the material described at the beginning in that a covering layer is disposed on the support on one side only and without a counteracting layer, in that the covering layer and the covering element of the side edge are produced from a plastic material filled with an inorganic filler, the covering layer having a thickness ranging from 5 to 10 mm, and in that the covering layer is connected to the support by means of a curable resin across its entire surface and substantially without the formation of bubbles.
In accordance with the invention materials are possible which, apart from their functional properties, also have an excellent decorative effect and are at least equal to the highly priced products discussed above in every respect. Furthermore, the material according to the invention permits an economic usage of the highly priced materials for the production of the covering layer and also offers considerable rationalisation potentials in relation to the production of the install able finished worktops. Moreover, in comparison with the conventional solid surface materials, one observes an improved cracking behaviour or cracking resistance, and the materials remain stable even in a humid environment.
Nforeover, the panel-shaped material according to the invention offers many different possibilities of shaping at edges.
~~urprisingly it has been shown that plastics that are filled with inorganic fillers are suitable for the manufacture of a covering layer that is in one piece with t:he covering element of the side edge ( s ) of the panel-shaped support without the feared problems of warping occurring if at first the covering layer is produced in one piece with the side edge covering element and then the panel-shaped support is connected to the covering 5 layer across its entire surface. In this case the observance of the thickness of the covering layer of approx. 5 to approx. 10 mm is important. The bonding of the covering layer, over the entire surface and substantially without the formation of bubbles, with the panel-shaped support guarantees also in use an excellent hot-pan resistance and resistance to cracking, even with the smaller layer thicknesses of the covering layer compared with the conventional solid surface materials, such as a . g . Corian~. In the case of the panel-shaped materials according to the invention a counteracting layer can be dispensed with.
When sticking the covering layer to the panel-shaped support, a curable resin layer is preferably used, in which case the resin material is applied in such a quantity that it can compensate existing unevenness in the rear of the covering layer and also of the corresponding support surface. This considerably simplifies the production of the covering layer from the plastic material, since there one's attention can be fixed upon the visible side and no special measures have t:o be taken on account of the surface condition of the rear side.
The adhesive may be chosen from a plurality of obtainable materials, in which case the following demands are preferably placed on the adhesive:

The adhesive is to have a high temperature stability as is guaranteed for example by polymerising adhesives, such as e.g polyurethane adhesives etc., so that with temperature stresses, e.g. by a hot pan being set down, non-positive bonding with the support is still guaranteed.
Furthermore, the adhesive system is to have a balanced elasticity and hardness. Firstly transverse stresses, caused by local temperature stresses, can be transmitted to the support and distributed to avoid cracking, and secondly the adhesive may not be too brittle, so that small differences in the thermal expansion of the bonding system comprising support/covering layer do not result in the warping of the top.
Hitherto the plastic material has not been described in any further detail, apart from the fact that it is to contain an inorganic filler. A large number of different filled plastic materials are also possible, and, without any claim to completeness, reference is made to the materials that were described in the following documents and are also related thereto: DE-A-24 49 656 and US-A-3,847,865.
Depending on whether surfaces are to be produced in plain colours or with a design similar to granite, different recipes come to be used for the production of the covering layer.
A curable reaction mass which forms a polymer phase with a particle-shaped filling material incorporated therein has proved to be particularly suitable for the manufacture of the covering layer and the covering e:Lement of the side edges) of the support. The polymer phase itself is preferably substantially free from inorganic fillers and if need be contains up to 20 o by weight, preferably up to 15 o by weight, even better preferred up to 10 % by weight of inorganic adjuvants in particle form. The particle-shaped filling material has to be swellable in the polymer phase and comprises a resin material filled with an inorganic filler. The filled resin material comprises a percentage of inorganic filler ranging from 50 to 80 % by weight with an average grain size of approx. 50 to 100 ~m and also if necessary pigments to achieve particular colour effects. The filling material (for brevity called granulate in the following examples) is again used in a grain size of approx. 60 to 8000 ~m and can be contained in the plastic material in a percentage of approx. 30 to 75 % by weight.
The viscosity of the mixture of the reaction mass consisting of swollen filling material and polymer phase (if necessary with inorganic adjuvants) is at such a level that the mixture can no longer be pumped or cast.
Precisely such mixtures are however eminently suitable in a mould disposed in a press to produce a cavity-free filling of the mould without the destruction of the particle structure occurring and this spoiling its decorative and/or contrasting effect on the visible side, if this is desired, e.g. in the case of granite design.
However, it is also possible to produce plain-coloured covering layers and covering elements for the side edges of the support, in which case alternatively reaction masses and mixtures are resorted to which are based on g the disclosure of the documents discussed at the beginning (DE-A-24 49 656 and US-A-3,847,865). The previously recommended mixtures with swellable filling material has the great advantage that, without special precautions relating to the method, visible sides of the covering layer are obtained which are free from flow marks. Such mixtures also avoid sedimentation problems and thus an unequal distribution of the fillers in the plastic material.
The reaction mass is preferably used on a base of polyester or poly(meth)acrylic systems.
The covering element of the side edges of the support is preferably in the form of a cover strip, also called gross edge below, in which the thickness of the cover strip is preferably chosen so that machining is possible.
The thickness of the cover strip will preferably be 1.3, better preferred 1.5 times or more the thickness of the covering layer. The cover strip can then be shaped and in the case of the selection of material described above can also be machined and processed with conventional wood working machines.
F~n excellent resistance to hot-pans of the panel-shaped materials according to the invention is achieved with such covering layers, whose thermal conductivity perpendicular to the surface of the covering layer is at least approx. 0.6 W/mK. This guarantees an adequate dissipation of the heat to the support.

In the case of preferred panel-shaped materials the modulus of elasticity of the plastic material filled with inorganic filler is approx. 5000 N/mm' or more.
The panel-shaped support may be chosen from a plurality of materials, in which case wooden materials are preferred on account of the ease of machining and processing. The wooden materials used preferably have a timber moisture of 7 - 8 % by weight. An eminently suitable wooden material for the support lies in the so-called OSB panels (OSB = oriented structural board). In these panels dimensions for contraction and swelling should be achieved, in o per o change in timber moisture, which for the panel thickness are less than 0.5 o and for the panel width are less than 0 . 1 0 . The longitudinal swelling is virtually insignificant, but it is less than 0.02 %.
An alternative, which is at least equivalent, is to be seen in bar-bonded solid wood panels or end-grain panels (also called cross-grained panels). In this case the ~>rocedure can advantageously be such that the wooden bars c>r blocks for forming the panel are inserted individually, and provided with adhesive, into the prepared covering layer with cover strips. In this manner the wastage of wooden material can be reduced to a minimum. In this case correspondingly predried and planed squared timbers and end-grain piece of wood are either wetted on two sides or on all sides with a waterproof glue and introduced individually one after another into a half-shell that is formed by the covering layer and the cover strips on all sides, and which is similar to a baking sheet mould. In this manner the bar adhesive bonding can be produced from squared timbers or the end-grain panel directly in the half-shell. Of course, a prefabricated rod-bonded, bar-bonded or end-grain-bonded panel can be stuck into the half shell after 5 being cut to size. If necessary, a wood veneer or an aluminium foil can be stuck as the lower covering layer and the complete structure is cured in a press under pressure.
10 A one- or two-constituent polyurethane resin is preferably used as the adhesive in this case. The temperature resistance during short-term peak temperatures has to lie at > 90 °C and for steady load at > 70°C. A certain measure for the elasticity/brittleness of the adhesive is given firstly by the Shore hardness and secondly by the elongation at break. So-called semi-rigid adhesives having a Shore hardness of 70 to 90 (Shore A) are preferred, preferably with a Shore hardness of approx. 75 (Shore A).
The rod-bonded, bar-bonded or end-grain-bonded panel that i.s produced in this manner in the half-shell as a support has even better properties with respect to moisture swelling than the previously recommended OSB panel and t:he glueing into place in large-format half-shells is simpler and therefore more economical.
7.n the method according to the invention for the manufacture of the panel-shaped materials according to t:he invention, it should firstly be noted that the covering layer together with the covering element of the ride edges) of the panel-shaped support is formed in one piece from a plastic material and that the panel-shaped support is stuck to the rear of the covering layer across the entire surface and substantially without the formation of bubbles by means of a curable resin.
If all side edges of the support are covered, together with the covering layer a half-shell mould similar to a baking tin is produced, into which the panel-shaped support is stuck. In this case prefabricated panels can be used, which are cut to the required dimensions, or however, as described above, end-grain blocks or rod-bonded or bar-bonded panels are directly produced in the half-shell. In the latter case the bars are preferably laid in the longitudinal direction, in which case the orientation of the annual rings is taken into consideration, so that the widthwise swelling is kept to a minimum. For this purpose the bars are laid so that the annual rings of bars that are directly adjacent to one another are always perpendicular to one another. In the case of end-grain blocks the fibre direction of the end-grain timber is always oriented perpendicularly to the plane of the covering layer.
P,n adhesive bonding between the end-grain blocks or rods c~r bars, i.e. of the contact faces of the wooden blocks or rods or bars that are disposed perpendicularly to the plane of the panel, may possibly be omitted, in which case advantages result, i.e. the end-grain blocks and rods or bars can move in relation to one another, which has a favourable effect on warping of the panel.
7.f the wooden bars or rods or the end-grain blocks remain unbonded, a moisture-crosslinking polyurethane adhesive which is expandable is advantageously used. On account o_f the pressing force applied during curing, formation of bubbles is avoided in the adhesive surface that connects the support with the covering layer, however also a~~hieves the effect that adhesive foam penetrates into the joints between the wood bars or rods or end-grain blocks and sticks them laterally to one another and thus fixes them.
In the method according to the invention, the swollen mixture of the curable reaction mass is preferably pressed and cured in the mould at 100 to 130°C and a pressure of 3 to 10 bar. In so doing firstly the region of the side edge cover strips) and then the covering layer is cured by controlling the temperature of the mould.
The mixture of the reaction mass is preferably cured for a period of 20 min. to 1 hour.
In a preferred refinement of the method according to the invention, a mould is used to produce the covering layer and the cover strip(s), during which the part of the mould to be allocated to the cover strips can be heated separately from the part of the mould corresponding to the covering layer.
In this case these parts of the mould are preferably heated so that the cover strips are cured with a lead time of approx. 2 to 10 min, in relation to the covering layer.
The covering layer is again preferably cured starting on t:he visible side.

The cured covering layer with the cover strips for the side edges is preferably subjected to a tempering stage at a temperature of below the glass transition point, preferably after being removed from the mould.
In order to make the panel-shaped material according to the invention unsusceptible to the effect of water, a varnishing of the rear side may be indicated.
Alternatively, for example, an aluminium foil, preferably varnished on one side, may be stuck on as a water vapour barrier, which for reasons of easier handling and resistance to injury should have a thickness of > 100 ,um.
These and other advantages of the invention are explained in further detail below by means of examples.
1. Manufacture of the half shglls Example 1' fine-grained granite designs Recipe 29,790 g acrylic syrup (20 o with PMMA prepolymer, molecular weight 100,000 Dalton) 1,323 g trimethylolpropantrimethacrylate (TRIM) 88 g stearic acid 110.3 g di-(4-tert-butylcyclohexyl)-peroxidi carbonate (BCHPC) 189.0 g di-l.auroylperoxyd (LP) 11,100 granulate unpigmented, 0.1 - 0.6 g mm 4,500 granulate white, 0.1 0.6 mm g -17,650 granulate black, 0.1 0.6 mm g -After mixing one obtains 70 g of a substance which at first is still fluid, which has swollen after 1.5 hours depending on temperature and therefore can no longer be pumped.
Starting size for a half-shell with the external dimensions 110 cm x 65 cm : 11.4 kg After casting one obtains a half-shell with an average sized design similar to granite in the basic colour green (cf. Figure 1).
Example 3 ~ Rough granite designs Recipe 29,'790 g acrylic syrup (20 % with PMMA prepolymer molecular weight 100,000 Dalton) 1,323 g TRIM
88 g stearic acid 110.3 g BCHPC
189.0 g LP
22,100 g granulate unpigmented, 0.1 - 0.6 mm 3,900 g granulate unpigmented, 2.5 - 5 mm 2,800 g granulate white, 0.1 0.6 mm -550 g granulate white, 0.6 1.2 mm -1,100 g granulate white, 1.2 2.5 mm -550 g granulate black, 0.1 0.6 mm -550 g granulate black, 0.6 1.2 mm -1,100 g granulate black, 1.2 2.5 mm -550 g granulate blue, 0.1 0.6 mm -5,250 g ATH (as Example 1) grain size distribution 0 - 100 ~m average grain size d5o - 35E.cm The resin is presented and all liquid constituents that 5 are to be dissolved are added and intensively mixed.
Then the ATH and the granulate is added and again intensively mixed. Subsequently the mixture is degassed.
After mixing one obtains 70 kg of a substance which at 10 first is still fluid, and which has swollen after 1.5 hr depending on the temperature and is therefore no longer pumpable.
Starting size for a half-shell 15 with the external dimensions 100 cm x 65 cm . 11.4 kg After casting one obtains a half-shell with a medium-sized design similar to granite in the basic colour grey (cf. Figure 1).
fxamgle 1 - 3' Casting and hardening the half-shells with Granite design:
A simple baking sheet mould, consisting of a steel frame and a brass sheet, which was bent so that it forms the recess of the half-shell and at the same time lies over t=he frame, acts a test mould (110 cm x 65 cm). The sheet was soldered at the corners.
Frame and lower panel side can be heated separately.
The upper mould is constructed as a male mould to form 1=he geometry of the half-shell.

In the test non-metallic materials, such as e.g. wood materials, have proved to be suitable as material for the upper mould, which however can still be heated or cooled from the rear side. Polymerisation is performed in a press with the use of pressure and temperature.
A half-shell of the type represented in Figure 1 is produced.
The baking sheet is tempered to 40 °C and is filled outside the press with 11.4 kg casting compound. The casting compound is introduced as a hank into the centre of the sheet. Then polyester film is laid down as a z°elease film and the compound distributed. Then the baking sheet is moved into the press and the press closed.
A rubber seal which is situated in a groove in the upper rnould and is protected from the action of MMA by the release film acts as a mould seal. The seal is pressed <~gainst the frame during the closure of the press. The air can escape between foil and frame. The shrinkage i~hat occurs during curing in the plane of the panel is compensated by the following of the press.
In the edge region the upper mould can be provided with a hose, rubber hollow section or the like that can be supplied with compressed air. During curing the nose or the rubber hollow section is supplied with compressed air with a pressure of approx. 3 to 8 bar, so that during curing the shrinkage which also occurs parallel to the plane of the panel can be compensated.

The pressure of the compressed air depends on the surface pressure of the press in the limits mentioned above.
The heating plate temperature in the press is 120°C. A
"temperature ramp" is only produced if the baking sheet requires approx. 5 min. in order to assume the heating plate temperature.
Temperature frame: 120°C (temperature lead over the baking sheet 5 minutes) 'Temperature hot plate: 120°C
P,dj ustment press : 0 - 3 minutes : 5 0 b a r (hydraulic pressure) From 3 minutes: 100 bar (hydraulic pressure) cycle time: 35 minutes 7.f the half-shell is cooled in the press to 40°C, slight warping occurs. However, if the press/mould is opened and the baking sheet/moulding is cooled only on one side from below to 40°C (15 minutes), straight panels are obtained. The panels are preferably tempered before bonding to the support at 120°C for 5 hours.
example 4' Manufac ure of a half-shell in plain colours Recipe 14,362 g acrylic syrup (27 o with PMMA prepolymer, 1g molecular weight 100,000 Dalton) 314 g TRIM
438 g stearic acid 54 g BCHPC
93 g LP
373 g 3-trimethoxysilyl-propylmethacrylate (MEMO) 22,440 g ATH (as Example 1) grain size distribution 0 - 100 um average grain size d5~ = 35 ~cm 1,200 g coloured paste (acrylic syrup/titanium oxide pigment in the weight ratio 3:1) The resin is presented and all liquid constituents that are to be dissolved are added and intensively mixed.
Then the ATH is added and again intensively mixed.
Subsequently the mixture is degassed.
40 g of a fluid dispersion with a viscosity of 5,000 mPa ~ s is obtained.
~3tarting size for a half-shell with the dimensions 100 cm x 65 cm . 12.6 kg After casting a white half-shell is obtained (cf. Figure .L ) .
With the same mould technology work can also be carried out with fluid dispersions:

When laying the foil on the surface of the dispersion, relatively large air bubbles are often incorporated, which later would be unacceptable as defects of the rear side. By laying a thin fibrous web on the rear side the air can escape better laterally and defect-free backs are obtained.
The baking sheet is moved into the press. A temperature ramp during heating is only produced if the mould requires approx. 5 minutes to assume the heating plate temperature.
'Temperature frame: 110°C (3 min. temperature lead over the baking tin) Temperature heating plate: 110°C
Set-up press: 0 - 3 min.: 80 bar from 3 min.: 120 bar Cycle time: 50 min.
To obtain straight panels, the half-shell from Example 4 has to be cooled for approx. 15 minutes in the press ;under pressure), in contrast to the designs according to Example 1. After that tempering is carried out at 120°C
for approx. 5 hours.
2 Glueina of half-shell and support panel Example 5' Adhesive bonding of bars / adhesive bonding of end-grain timber Endless bars 30 x 30 mm (timber moisture approx. 7 % by weight) are glued on the top and under side and inserted into the half-shells according to Example 1.
Alternatively in this stage end-grain blocks 60 x 80 mm 5 (wood moisture 7 o by weight) with a length in the fibre direction of 30 mm are used.
P. moisture-crosslinking polyurethane adhesive resin (company Fuller ICEMA 145/66: consistency pasty) is used 10 as adhesive. Excess adhesive also flows into the joints between the rods perpendicularly to the plane of the top.
This is assisted by an expansion of the adhesive. On account of the pressing during the curing of the adhesive (pressing force approx. 1 to 2 bar) the formation of 15 bubbles is prevented in the adhesive layer towards the covering layer. For example, a 100 fcm thick aluminium foil that forms a vapour barrier is suitable as a covering element on the rear of the panel-shaped material.
The entire structure is cured in a press at ambient temperature.
F?ressing time . 2 hours Example 6' Adhesive bonding of OSB panels The already cut-to-size OSB panel having a thickness of 34 mm is laid into the half-shell that lies on the visible side. The panel is provided in its centre with <~ bore (radius 5 mm) through which the adhesive can be :injected. Then a rubber cloth, held with a frame, is laid over the panel. A connection piece for the injection of adhesive is inserted into the centre of the rubber cloth, the connection piece (closed with a ball valve) is introduced into the previously bored hole. The frame of the rubber cloth is pressed against the flat table. Then the cavity beneath the cloth is evacuated.
By opening the ball valve the adhesive (company Fuller, ICEMA 145/66, consistency fluid) is slowly sucked by the action of the vacuum between the support panel and half-shell.
After the injection of a specific quantity, the ball valve is closed, but the vacuum is maintained. The rubber cloth acts under the column of air of the external normal pressure as a press. The pressing pressure is approx. 0.6 bar.
A moisture-crosslinking polyurethane resin is used as the adhesive. The panel can be removed after 2 hours.

Claims

1~

Claims

1. A panel-shaped material, in particular for use as kitchen worktop, table top, with a panel-shaped support made from a wood material, a covering layer which is joined to the panel-shaped support across the surface thereof and with a covering element which is disposed along at least one side edge of the support and which is constructed in one piece with the covering layer, characterised in that a covering layer is disposed on the support on one side only and without a counteracting layer, in that the covering layer and the side edge covering element are produced from a plastic material filled with an inorganic filler, the covering layer having a thickness ranging from 5 to 10 mm, and in that the covering layer is connected to the support by means of a curable resin across its entire surface and substantially without the formation of bubbles.

2. A panel-shaped material according to Claim 1, characterised in that the covering element is constructed as a cover strip and in that the thickness of the cover strip is preferably greater than the thickness of the covering layer.

3. A panel-shaped material according to Claim 2, characterised in that cover strips that are in one piece with the covering layer are disposed on all side edges of the support.

4. A panel-shaped material according to Claim 2 or 3, characterised in that at least one of the cover strips forms a visible edge and has a thickness which permits machining.

5. A panel-shaped material according to Claim 4, characterised in that the cover strip forming the visible edge has a thickness which is at least 1.3 times, moreover preferably at least 1.5 times, the thickness of the covering layer.

6. A panel-shaped material according to one of the preceding Claims, characterised in that the thermal conductivity of the covering layer perpendicularly to its surface is at least 0.6 W/mK.

7. A panel-shaped material according to one of the preceding Claims, characterised in that the modulus of elasticity of the plastic material filled with inorganic filler is 5000 N/mm2 or more.

8. A panel-shaped material according to one of the preceding Claims, characterised in that the support is formed by a so-called OSB material.

9. A panel-shaped material according to one of Claims 1 to 7, characterised in that the support is formed by a rod-bonded or bar-bonded wooden material or an end-grain timber panel.

10. A panel-shaped material according to one of Claims 8 or 9, characterised in that the timber moisture of the wooden material is 7 to 8 % by weight.

11. A method for the production of a panel-shaped material according to one of Claims 1 to 10, characterised in that the covering layer together with the covering element for the side edges is formed in a mould by means of curing a plastic material that is filled with an inorganic filler, and in that the panel-shaped support is stuck onto the rear of the covering layer without a counteracting layer by means of a curable resin across its entire surface and substantially without the formation of bubbles.

12. A method according to Claim 11, characterised in that to form the covering layer from plastic material a mixture of a curable reaction mass is manufactured to form a polymer phase with a particle-shaped filling material incorporated therein from a resin material filled with the inorganic filler, whereby the polymer phase comprises up to 20 % by weight inorganic adjuvant, in relation to the plastic material, whereby the particle-shaped filling material can swell in the reaction mass, whereby the filled resin material comprises a proportion of inorganic filler ranging from 50 to 80 % by weight with an average grain size of 5 to 100 µm and whereby the filling material has a grain size ranging from 60 to 8000 µm and is contained in the plastic material in a percentage of from 30 to 75 % by weight, in that the filling material is left in the curable reaction mass to swell until the mixture can no longer be cast, in that for curing the mixture is poured into one of the mould halves that is disposed in a press, the mould is closed and a predetermined mould pressure is applied to the mould and the mixture is thermally cured in the closed mould.

13. A method according to Claim 12, characterised in that the mixture is pressed and cured in the mould at 100 to 130°C and pressure of 3 to 10 bar, whereby firstly the region of the cover strip(s) and then the region of the covering layer is cured by controlling the temperature of the mould.

14. A method according to Claim 13, characterised in that the mixture is cured for a period of 20 min to 1 hour.

15. A method according to one of Claims 11 to 14, characterised in that a mould is used to produce the covering layer and the cover strip(s), during which part of the mould that is to be allocated to the cover strips can be heated separately from the part of the mould corresponding to the covering layer.

16. A method according to Claim 15, characterised in that the heating of the parts of the mould is chosen so that the cover strips are cured with a lead time of 2 to 10 min. in relation to the covering layer.

17. A method according to one of Claims 11 to 16, characterised in that the covering layer is cured starting on the visible side.

18. A method according to one of Claims 12 to 17, characterised in that the press is followed during the curing to compensate for the shrinkage.

19. A method according to one of Claims 11 to 18, characterised in that a press is used with an upper mould which at its edge comprises an inflatable rubber hollow section, and in that the hollow section is supplied with compressed air with a pressure of 3 to 8 bar during curing.

20. A method according to one of Claims 11 to 19, characterised in that the curable resin is injected under vacuum between the support and the covering layer, whereby the resin is supplied through a substantially central injection hole in the support.

21. A method according to one of Claims 11 to 19, characterised in that the panel-shaped support is manufactured from a plurality of individual bars of wooden material in the shape formed by the prefabricated covering layer with cover strips integrally formed in one piece.

22. A method according to one of Claims 11 to 21, characterised in that the cured covering layer with cover strips is subjected to a tempering stage at a temperature of below the glass transition point, preferably after being removed from the mould.

23. A method according to one of Claims 11 to 22, characterised in that a single-constituent or two-constituent polyurethane adhesive is used as a curable resin.

24. A method according to Claim 23, characterised in that the polyurethane adhesive is expandable.