FR3062813A1 - PANEL BASED ON WOOD - Google Patents

Abstract

Wood-based panel comprising a body (4) having a top (1) of large surface, plane and a bottom (2) connected by edges (3), the panel is made of a wood-based material, especially particles or wood fibers pressed with a binder. The wood-based material of the body (4) is of standard type without hydrophobic treatment. The panel has a cover layer (5) of hydrophobic-treated wood-based material attached to the top (1) of the body (4).

Description

Field of the invention

The present invention relates to a wood-based panel comprising a body having a large, flat top surface and a bottom connected by edges, the body being of a wood-based material, in particular in pressed wood particles or fibers. with a binder, the wood-based material of the body being of the standard type without hydrophobic treatment.

The invention also relates to a work panel, in particular a kitchen work surface formed from such a wood-based panel.

State of the art

The wood-based panels concerned by the invention are known. They are used as a support or as a panel to make composite elements for interior equipment, work panels, in particular panels forming kitchen worktops, window shelves or flooring panels, wood panels. wall covering, etc. Typically, a wood-based panel of the type defined above has a planar body of a wood-based material having a large area top and a corresponding large area bottom; the top and bottom are connected by edges. Typically, the body is made of a wood-based material formed from fibers or particles pressed with a binder. The wood-based material and the binder have no hydrophobic characteristics.

DIN EN 312 applies to wood-based panel bodies and DIN EN 622 applies to medium density fibreboard (also called MDF panels) and high density fibreboard (also called HDF panels) . The fibers of the body are maintained by a binder compressed at the same time with the fibers in particular a duroplastic binder such as for example a urea-formaldehyde resin (DE 10 2010 003 437 Al).

A work panel using a wood-based panel of the type defined above typically has a body formed by a wood-based panel and the top of which is provided with a decorative covering sheet (laminate sheet HPL) as a top layer on 3062813. The underside of the body is coated with a counterbalancing layer which generally consists of kraft paper impregnated with resin and protecting the underside against the action of steam and water; this sheet also serves to globally balance the panel against deformation. In the case of the characteristic nominal thickness of a 38 mm wood-based panel, the surface layer is typically a sheet of high-pressure laminate having a thickness of between 0.6 mm and 0, 8 mm; the kraft paper forming the counterbalancing layer at a thickness of between 0.1 mm and 0.2 mm. The total thickness of such a panel is around 39 mm.

For some applications it is desirable to use a water resistant panel. In this case, the fibers and particles of the body are preferably strongly compressed and a high proportion of hydrophobic binder is used. The wood-based panel obtained is then heavy and moreover its manufacture is expensive.

As a variant, it is also possible to produce sheets of HP laminate, of greater thickness, formed from several layers of kraft paper impregnated with resin, which are compressed and used only for the surface coating. However, such thicker HP laminate sheets are heavy and expensive.

Wood-based panels with hydrophobic treatment are particularly interesting as a basis for manufacturing kitchen worktops and which, according to the most recent requirements, incorporate a sink basin which comes flush with the upper surface.

The state of the art for the present invention is known in practice. This is a kitchen worktop, the body of the wood-based panel is a lightweight particle board (the specific weight of which is approximately 500 kg / m ³ ). It is a three-layer particle board with a low density intermediate layer and sanded top layers on top and bottom. A hydrophobic surface layer is glued to the top of the body. It is a high pressure laminate sheet. A counterbalancing layer is glued on the underside; this layer is also a sheet of high pressure laminate much thinner than the top sheet. The edges (edges) connecting the top and bottom of the wood-based panel are protected by a plastic edging strip.

For a total thickness of the working panel of 38 mm, the body constituted by a particle board, has a thickness only of approximately 35 mm, the surface layer constituted by the sheet of high pressure laminate (HPL) on the other hand has a thickness of approximately 2.4 mm and the counterbalancing layer consisting of a sheet of high pressure laminate (HPL) has a thickness of approximately 0.6 mm. This panel thus has a sheet of hydrophobic high pressure laminate which constitutes the surface layer and whose thickness is three times that of a normal panel.

Despite the greater thickness of the surface layer, to integrate a sink pan into the panel arriving at the top surface, it is necessary to work very precisely and achieve a perfectly waterproof bonding at the level edge of the sink pan so that moisture cannot pass between the edge of the sink pan and the edge of the laminate sheet. Moisture entering would swell the lightweight particle board.

In practice, difficulties have been noted with panels of the type described above. For this reason it has already been proposed to stick in the cutout of the panel, in addition a part of the plastic wall which constitutes the housing receiving the edge of the sink pan or of a component of this type (DE 10 2006 056 786 Al). It is obvious that this manufacturing process is very expensive insofar as the part of the plastic wall cannot be put in place, except where the sink is integrated, for example.

Purpose of the invention

The present invention aims to develop a wood-based panel and a work panel and overcoming the drawbacks mentioned above without using additional plastic parts.

Presentation and advantages of the invention

To this end, the subject of the invention is a wood-based panel comprising a body having a large, flat surface and a bottom connected by edges, made of a wood-based material, no.3062813 particularly in particles or fibers of wood pressed with a binder, the wood-based material of the body being of standard type without hydrophobic treatment, this panel being characterized in that it comprises a covering layer of a wood-based material with hydrophobic treatment fixed on the top from the body.

In other words, the subject of the invention is a wood-based panel, the top of the body of which is provided with a covering layer, made of a wood-based material with hydrophobic treatment, this layer being fixed above the body. The panel thus produced has a surface layer which is water resistant and which, unlike the prior art, is not on the top of the body but on the upper side of the covering layer. Thus, the top of the body achieves a thickness of total layer resistant to water, that is to say having a hydrophobic treatment and this total layer is much greater than in the prior art from which the invention, in particular a thickness at least twice and preferably at least triple up to four times that of the existing layer according to practice in the prior art.

In the case of such a large layer thickness of a hydrophobic material or having a hydrophobic treatment, the risk that moisture can penetrate into the body of a wood-based material without hydrophobic treatment, has a very low probability being given the very long interval filled with water resistant glue and / or sealing medium. Thus, this assembly has the same effect as a wood-based panel having a complete hydrophobic treatment although here the body of the panel is always made of a wood-based material, standard, economical without any particular hydrophobic treatment. This solution is economical and the wood-based panel has a much lower total weight than that of a panel treated completely so as to be hydrophobic, whether it is a wood-based material or the laminate layer. high pressure.

Ultimately, we thus have all the advantages of integration, in particular the level sink bowl with the top, etc.

without the disadvantages, that is to say the significant cost and weight.

The integral connection of the cover layer and the top of the body is preferably made by gluing with a usual glue for this, for example a glue based on urea, etc. Reference should therefore generally be made to the bonding of wood-based materials, according to the state of the art.

The greater thickness of the covering layer applied to the top of the body according to the invention makes it possible, for example, to integrate a baking sheet with a thickness of 7 mm to 10 mm, completely level with the covering layer. . The body of the panel below, at the level of the hob support, remains protected by the thin layer of the covering layer material. This provides perfect protection of the panel body without hydrophobic treatment.

According to a particular characteristic, the wood-based panel according to the invention is provided with a covering layer made of a wood-based material treated in a hydrophobic manner, the body of which itself consists of a particle board, in particular a panel light particles. Alternatively, it is possible, for example, to use plywood, MDF medium density fiber board, HDF high density fiber board, depending on the desired application, produced with a usual binder such as, for example, a melamine formaldehyde resin. . In principle, the body is a light panel, for example, a honeycomb panel.

For the cover layer according to the invention, an MDF layer with hydrophobic treatment is used. Due to the higher density compared to that of a lightweight panel, an MDF layer is inherently more resistant to moisture. It can be carried out by compression with a hydrophobic binder, for example, a melamine resin or PMDI and then it is practically hydrophobic. As a variant of a hydrophobic treatment of the MDF layer, it is also possible to use a reinforced phenolic urea resin. It is also possible to apply known processes for acetylation or heat treatment of wood (wood with heat treatment); these methods can be applied cumulatively or alternatively. Typically, mixtures of wax or paraffin are often used to enhance this function. The cost of an MDF layer as a cover layer with hydrophobic treatment is barely higher than that of an MDF layer without hydrophobic treatment. If necessary, these costs are in any case much lower than those of thicker high pressure laminate panels.

According to the invention, the thickness of the cover layer represents between 10% and 30% of the thickness of the body. For a standard thickness of wood-based panels of around 37 mm, like those used frequently for interior equipment, there is for example, a thickness of the body between 25 mm and 32 mm and a thickness of the covering layer between 3 mm and 12 mm. The remaining part of the wood-based panel is always made of a standard, economical wood-based material. Where the hydrophobic characteristic of wood is necessary, namely on the surface, we have the characteristic of the invention.

For a panel according to the invention, the upper side comprises the covering layer already mentioned, bonded to the wood-based panel, with a hydrophobic surface layer constituted by a sheet of high pressure laminate (HPL). Alternatively, a laminate sheet can also be used directly as the surface layer. In this case, the surface layer consisting of a decorative paper impregnated with resin is applied directly to the top of the wood-based panel.

However, in a particularly preferred manner, the production of the work panel according to the invention in particular in the form of a kitchen worktop panel is produced with a surface layer constituted by a sheet of high pressure laminate (HPL) produced separately and then glued in a later step to the wood-based panel.

The panel according to the invention, in particular the panel forming a kitchen worktop, has a counterbalancing layer adapted to the surface layer but provided on the underside so that the panel does not deform. This corresponds to the usual practice of the technique.

Starting from a total thickness of the panel of approximately 38 mm, it is advantageous according to the invention that the body has a thickness of between 25 mm and 32 mm, the covering layer a thickness of 3 mm to 12 mm, and the surface layer a thickness of 0.5 mm to 3 mm, preferably between 0.7 mm and 1.5 mm; the counterbalancing layer, as far as provided, will preferably have a thickness of approximately 0.4 mm for the HPL laminate or approximately 0.1 mm for kraft paper.

In the case of a wood-based panel with direct coating, for a total thickness of the panel of approximately 38 mm, the body will have a thickness of between 25 mm and 34 mm, the covering layer, a thickness of 3 mm at 12 mm and the surface layer a thickness between 0.1 mm and 1.2 mm and preferably between 0.1 mm and 0.8 mm.

Drawing

The present invention will be described below in the case of an example of a panel shown in the single appended figure which is a partial sectional view of a panel according to the invention. Description of an embodiment

The panel (work panel) shown in the single figure is a wood-based panel having a body 4 with a top 1, plane, of large area and a bottom 2 corresponding, as well as edges (edges) 3 connecting the above below. The body is made of a wood-based material. The body is in particular a panel of particles or of fibers compressed with a binder, that is to say a panel of particles, if necessary also called medium density fibreboard MDF or a high density fiber panel HDF, where appropriate. also a plywood panel.

According to the invention, the top 1 has a covering layer 5 fixed together. This covering layer is made of a wood-based material with hydrophobic treatment. While the wood-based material of the body 4 is a standard material without hydrophobic treatment, the cover layer 5 is also constituted by a wood-based material, but with a hydrophobic treatment. The body 4 of the embodiment shown is produced as indicated as a light panel while the cover layer 5 is an MDF layer with hydrophobic treatment. The edges (edges) 3 of the body 4 and of the covering layer 5 are protected by an edge band 3 ’.

The top of the cover layer 5 is provided with a water-resistant surface layer 6 which, in the preferred embodiment shown, is a sheet of high pressure laminate (HPL). In the preferred example shown, the underside of the body 4 has a counterbalancing layer 7 which is a sheet of counterbalancing paper.

For dimensional specifications, the total thickness of the work panel is approximately 38 mm; the body 4 has a thickness of between 25 mm and 32 mm; the cover layer 5 has a thickness of between 3 mm and 12 mm and the surface layer 6 has a thickness of between 2 mm and 3 mm and the counterbalance layer 7, as far as it is provided, has a thickness of between 0.5 mm and 3 mm and preferably between 0.7 mm and 1.5 mm.

The practical embodiment as presented has a light panel forming the body 4 with a thickness of 27 mm, the cover layer 5 has a thickness of 10 mm and the surface layer 6 in (HPL) has a thickness of 1.0 mm; the counterbalancing layer 7 has a thickness of 0.1 mm. Overall, there is thus a thickness of 38 mm which is the total thickness desired for the work panel of this exemplary embodiment.

For example, for a nominal thickness of the wood-based panel of approximately 28 mm, there will be suitable thicknesses of the body 4 and of the covering layer 5, for example from 15 mm to 22 mm for the body 4 and of 3 mm to 12 mm for the cover layer 5.

As it appears on the left of the figure, the thickness of the adaptation, edge side, of the panel to receive a sink pan is a thickness of hydrophobic material equal to 11 mm, which is more than four times the height of the surface layer 6 of the prior art; this is a HPL5 high pressure laminate sheet. The delicate area of the gap, on the edge, of the sink bowl is integrated so as to be flush with the surface of the top; this problem is thus resolved without the weight of the panel becoming excessive or its cost being too great.

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NOMENCLATURE OF MAIN ELEMENTS

Top / top side

Bottom / underside

3 Edge / edge

3 ’Edgebanding

Body

Cover layer

Top layer îo 7 Counterbalance layer

Claims (10)

1 °) CLAIMS Wood-based panel comprising: a body (4) having a top (1) of large, flat surface and a corresponding bottom (2) connected by edges (3), made of a wood-based material, in particular of particles or fibers of wood pressed with a binder , the wood-based material of the body (4) being of standard type without hydrophobic treatment, panel characterized in that it comprises a covering layer (5) of a wood-based material with hydrophobic treatment, fixed on the top (1) of the body (4). 2 °) Wood-based panel according to claim 1, characterized in that the body (4) is a particle board, in particular a lightweight particle board. 3 °) Wood-based panel according to claim 1 or 2, characterized in that the covering layer (5) is a layer of medium density fibers with hydrophobic treatment, preferably pressed with a urea resin reinforced with melamine. 4 °) Wood-based panel according to one of claims 1 to 3, characterized in that the thickness of the covering layer (5) represents between 10% and 30% of the thickness of the body (4). 5 °) work panel including kitchen worktop comprising a wood-based panel according to one of claims 1 to 4, with a body (4), a cover layer (5) and a surface layer (6 ), hydrophobic, in a sheet of high pressure laminate (HPL) glued on top of the covering layer (5). 6 °) Work panel according to claim 5, characterized in that the underside of the body (4) of the wood-based panel has a counterbalancing layer (7) preferably in kraft paper, glued. 7 °) work panel according to claim 5 or 6, characterized in that for a total thickness of the panel of about 38 mm, the body (4) has a thickness between 25 mm and 32 mm, the cover layer ( 5) has a thickness of between 3 mm and 12 mm and the surface layer (6) has a thickness of 0.5 mm to 3 mm, preferably between 0.7 mm and 1.5 mm. 8 °) Work panel in particular kitchen worktop comprising a wood-based panel according to one of claims 1 to 4, with a body (4) and a cover layer (5), and a surface layer ( 6) hydrophobic, applied by direct coating on top of the cover layer (5), this surface layer being formed from a decorative paper impregnated with a suitable binder, such as a melamine resin and / or a urea resin -formaldehyde. 9 °) Work panel according to claim 8, characterized in that the underside of the body (4) of the wood-based panel is provided with a counterbalancing layer (7) in an impregnated kraft paper. 10 °) work panel according to claim 8 or 9, characterized in that for a total thickness of the work panel of about 38 mm, the body (4) has a thickness between 25 mm and 34 mm, the layer of cover (5) has a thickness between 3 mm and 12 mm, the surface layer (6) has a thickness between 0.1 mm and 1.2 mm and preferably a thickness between 0.1 mm and 0, 8 mm.