"Composite structure tile with wooden portion for coverings , in particular or floorings , and method for producing such tile"

FIELD OF APPLICATION

[0001] . The present invention relates to a composite structure tile with wooden portion for coverings, in particular for floorings, and method for producing such tile.

[0002] . The tile according to the invention may be used in particular to make floorings but also coverings for walls, if necessary combined with other covering materials .

STATE OF THE ART

[0003] . Composite structure tiles used to make floorings are known .

[0004] . In particular composite structure tiles with wooden portions comprising a layer in solid wood (typically a board) and a support base, attached to the underside of the wooden layer and made from an agglomerate of polyurethane resin and particles of rubber, are known. Generally the solid wood layer is at least 8mm thick, while the support base is 1.5 to 5 times thinner than the wooden layer.

[0005] . Thanks to its composition, the support base forms a barrier to humidity and water, also offering heat and noise insulation.

[0006] . The limitations of these known tiles are essentially connected with the scarce dimensional stability of the layer in solid wood, which is naturally subject to dimensional variations caused by the exchange of humidity with the atmosphere.

[0007] . Moreover the tiles described above are not suitable, for making floorings with floor heating systems. The upper layer of solid wood, combined with the support base, has in fact heat insulation properties which would invalidate or in any case obstruct the action of the underlying heating system.

SUMMARY OF THE INVENTION

[0008]. The purpose of the present invention is to provide a composite structure tile with wooden portion for coverings, in particular for floorings, which has a greater dimensional stability.

[0009] . A further purpose of the present invention is to provide a composite structure tile with wooden portion for coverings, which can be laid easily, immediately and rapidly without requiring the use of glues.

[0010]. A further purpose of the present invention is to provide a composite structure tile with wooden portion for coverings, which can be laid in highly humid conditions. [0011] . A further purpose of the present invention is to provide a composite structure tile with wooden portion for coverings, which can be used to make coverings, in particular for floorings, associated with heating systems with less impact on heating efficiency.

[0012]. A further purpose of the present invention is to provide a composite structure tile with wooden portion for coverings, which can be used as a modular element of a heating system.

[0013] . A further purpose of this invention is to provide a method of making a composite structure tile with wooden portion for coverings, which is easy and economical to implement.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] . The technical characteristics of the invention, according to the aforesaid purposes, are clearly evident from- the contents of the claims below and. the advantages of the same will be clearer from the following description made with reference to the appended drawings, showing one or more embodiments by way of non-limiting examples, wherein :

[0015]. - figures 1 ,3 and 5 show three schematic cross^ section views of the composite structure of a part of three tiles made respectively according to a first, a second and a third embodiment of the invention; [0016]. - figures 2, 4 and 6 show three exploded schematic views of the layers forming the composite structure of the tiles illustrated respectively in Figures 1, 3 and 5, in each scheme the grain direction of the wooden layers present in the composite structure being indicated by arrows; and

[0017] . - figure 7 shows a detail of a tile according to the invention, relative to attaching means between the tiles .

DETAILED DESCRIPTION

[0018] . The present invention relates to a composite structure tile with wooden portion for coverings, in particular for floorings, which is globally denoted by reference numeral 1 with reference to the appended drawings .

[0019] . According to a general embodiment of the invention, as may be seen in Figures 1, 3 and 5, the composite structure tile 1 comprises:

[0020] . - an upper sheet-like portion 2 in wooden material which defines the part destined to remain on view; and

[0021] . - a lower sheet-like portion 3 which acts as a support base and is glued to the upper wooden portion 2.

[0022] . The lower portion 3 is made from an agglomerate of rubber and/or cork particles or granules joined to each other by a water-repellent polymer binding agent.

[ 0023 ] . In particular, the rubber and/or cork particles or granules have a particle size of less than 4mm,, and preferably from 0.2 to 3mm. The lower portion 3 has a porous structure thanks to the intrinsic porosity of the granules of rubber (preferably vulcanised) and/or cork and thanks to the agglomeration of such granules bound by a binding agent matrix.

[0024] . According to the invention, the upper wooden portion 2 has a multilayer structure comprising a plurality of wooden layers 21 and 22 laid over each other and glued and positioned in relation to one another with the directions of the grains crossing.

[0025 ] . Thanks to the multilayer structure and . the crossing of the directions of the grains of the wooden layers 21 and 22 the deformations which would, rather, be present in an item of a similar thickness made in solid wood, can be drastically reduced.

[ 0026] . The use of a multilayer structure with crossing of the fibres not only makes it possible to stabilise the wooden portion 2 dimensionally, but at the same time to limit the quantity of wood to be used and thereby the thickness of the wooden portion 2 itself. For the same thickness the multilayer structure is more resistant and performs better than a single layer of solid wood. [0027] . The association of the multilayer structure with the lower portion 3 having the characteristics mentioned above not only enhances the aforementioned features of stability of the wooden portion making a further reduction of the . thickness of said wooden portion possible, but also gives the tile greater elasticity.

[0028] . The tile 1 thus proves easier to lay and more resistant to scratching than out and out solid wood. The particular tendency to resist scratching is shown by the results obtained in the Brinell tests. In the tile in question, both the support base and the wooden multilayer have elastic properties such as to dampen the falling of objects onto the surface of the tile preventing and/or significantly reducing the incision caused by.contact.

[0029] . Preferably, the wooden layers 21 and 22 are composed of veneer sheets, consisting in particular of sheets in sliced wood.

[0030] . Advantageously, the wooden layers 21 and 22 each have a nominal thickness of 0.3 to 2mm, and preferably of 0.5 to 1mm.

[0031] . As is known, in the wood processing sector, the "nominal thickness" of a sheet of wood is generally taken to mean a range of values of real thicknesses determined by machining tolerances. For example, sheets having a nominal thickness of 0.6mm may have effective average value ranging from 0.5 to 0.6mm depending on the wood used and the manufacturer.

[0032] . The wooden layers 21 and 22 may all be the same thickness or may be different thicknesses.

[0033] . The wooden layers may all be made from the same wood species, or be made from different woods. In particular, the inner wooden layers (not visible from the outside) may be made from a less valuable wood and only the outermost wooden layer destined to remain on view be made from a valuable wood.

[0034] . Preferably, the upper sheet-like wooden portion 2 has a total thickness Dl of 2 to 5mm. As already mentioned above, the reduction of thickness of the. wooden portion 2 compared to traditional solutions is rendered possible by the multilayer structure with crossed grains and by the association with a support base 3 made from an agglomerate of rubber and/or cork particles or granules joined to each other by a water-repellent polymer binding agent.

[0035] . Preferably, the lower sheet-like portion 3 which acts as a support base has a total thickness D2 of 6 to 10mm.

[0036] . According to a preferred embodiment, unlike the traditional solutions, the ratio D1/D2 of the thickness Dl of the upper wooden portion 2 to the thickness D2 of the lower portion 3 is less than 1, and preferably 0,20 to 0.90, and even more preferably, 0.30 to 0.70.

[0037] . In particular, the aforesaid values of the thickness ratio D1/D2 are achieved with thicknesses Dl of the sheet-like upper wooden portion 2 of 2 to 5mm and with thicknesses D2 of the lower sheet-like portion 3 of 6 to 10mm.

[0038] . In other words, the upper wooden portion 2 is less thick than the lower portion 3. This is rendered possible by the improved mechanical stability properties of the multilayer structure compared to a single layer in solid wood.

[0039] . Compared to traditional solutions, for the same total tile thickness, it is thus possible to have a support base 3 of increased thickness, with important advantages both in terms of acting as a barrier to the humidity coming from the underlying floor, and of sound absorption.

[0040] . As will be evident from the examples below, the lower portion 3 (support base) in fact assures the tile a good level of noise damping from walking.

[0041] . The lower portion 3 (support base) thanks in particular to its porosity has heat conductivity and heat resistance indexes making it suitable for use . in association with traditional floor heating systems.. [0042] . The aforesaid heat properties of the lower portion 3 and the substantial reduction of the heat resistance of the upper wooden portion 2 due to the reduction, of thickness compared to traditional boards in solid wood significantly reduce the impact of the tile oh the efficiency of an underlying heating system and thereby make it possible to lay the tiles 1 according to the invention on screed coats heated with traditional floor heating systems.

[0043] . Preferably, the water-repellent polymer binding agent connecting the rubber and/or cork granules- of the lower portion 3 to each other is a polyurethane resin.

[0044]. Advantageously, the overlaid wooden layers 21, 22 ^' are glued to each other with polyurethane glues, even though other glues may also be used such as vinyl, ureic or melamine-based.

[0045] . According to a particularly preferred embodiment, the upper wooden portion 2 and the lower portion 3 are glued to each other with polyurethane glues.

[0046] . The use of polyurethane glues to connect the wooden portion 2 and lower portion 3 makes it possible to create, an intermediate water repellent layer which during the life of the tile 1 acts as a barrier to any humidity coming from the floor or screed coat which the tile .1 has been laid on. [0047] . Advantageously, as will be explained further below, the wooden portion 2 may be subjected to a varnishing treatment aimed at preventing the penetration of humidity present in the environment into the wooden portion.

[0048] . The aforesaid expedients, combined with the multilayer structure with crossing of the grains, make the tile 1 less subject to deformation, related to the exchange of humidity with the outside and therefore dimensionally more stable.

[0049] . Thanks to the presence of the lower portion 3 and the flexibility and elasticity of the upper wooden portion 2, the tile 1 according to the invention has greater laying versatility than traditional systems which generally always require laying with gluing to the base .

[0050].. The particular composition of the lower portion 3- of rubber and/or cork and a polyurethane binding agent ensure a high level of friction between the support base and the surface to be covered, giving the tile a gripping capacity of its' own, even in the absence of glues. This behaviour is encouraged by the flexibility and elasticity of the upper wooden portion 2. These mechanical properties of the wooden portion 2 in fact permit the tile 1 to adapt to the surface to be covered and therefore permit the lower portion 3 to adhere better and more evenly to . the base increasing friction and thereby the grip.

[0051]. The tile 1 according to the invention therefore permits the laying of floorings without the use of glues .

[0052].. Advantageously, as already mentioned above, . the upper wooden portion 2 may be. subjected to a varnishing treatment, aimed at creating at least one water-repellent film, which prevents the penetration of humidity inside the upper wooden portion.

[0053] . Preferably, the film of varnish extends over both the main surface (destined to remain on view and more exposed to humidity during the life of the covering) ,. and the sides . corresponding to the thickness of the upper portion 2.

[0054] . Thanks to the finishing with varnish extending to the four sides too, the tile 1, as well as being more protected from humidity during the life of the covering, can be plastered and grouted without fear of any infiltration.

[0055] . In the case of laying with glues, the glue can come into contact with the sides of the tile thereby improving the hold compared to a tile with wooden portion of the traditional type.

[0056] . Any type of glue for laying coverings can be used to glue the tile 1, in particular cement glue, mon ^' o- component or bi-component glue, depending on the situation and requirements of the site.

[0057] . According to one particular embodiment (not shown in the appended Drawings) , the lower sheet-like portion 3 is provided with one or more grooves for housing electric resistors, preferably electric heating cables of the constant power type.

[0058] . Advantageously, the tile 1 may therefore be used to make floorings with a dual function as covering and heating system. This solution is particularly suitable for restoration or refurbishing works where often on account of problems of buildable volume the thickness of the flooring and of any floor heating systems must be reduced to a minimum.

[0059] . According to a particularly preferred embodiment, illustrated in particular in Figure 7, the tile 1 comprises fitting means 10, 11 aimed at ^' permitting the attachment of the tile 1 to one or more adjacent tiles.

[0060]. In particular, such attaching means comprise:

[0061] . - a groove 10 made on the perimetral sides of the tile 1;

[0062] . - at least one blade 11 (made for example from metal, in particular aluminium or in plastic material) inserted along at least one section of such groove 10 with a part 12 projecting from the tile and destined to be inserted in a free section of groove of an adjacent tile..

[0063] . Preferably, the groove 10 is made at the lower portion 3 and extends all along the perimeter of the tile itself .

[0064] . The presence of the aforesaid attaching means make the tile 1 not only easily connectable to the adjacent tiles, but at the same time easily removable with advantages in terms of maintenance and the repair of any damaged parts.

[0065] . The tile 1 according to the invention may be of any · shape (rectangular, square, polygonal, irregular, circular, elliptical) and size depending on the needs of the final user.

[0066] . Some embodiments of tile 1 will now ^■ be described.

[0067]. According to a first example (see Figures · 1.and 2), a tile 1 is made with a support base 3 (rubber, cork and polyurethane binging agent) having a thickness of 6mm and with an upper wooden portion 2 composed of four wooden layers in sliced oak having a nominal thickness of 0.6mm each and glued to each other with polyurethane glue, as illustrated in Figure 1. On completion of assembly the wooden portion 2 has an average thickness of about 2mm. The tile 1, of a rectangular shape, measures 1250 x 195 mm and is about 8mm thick. As illustrated in Figure 2, the four wooden layers 21a, 21b, 21c, and 21d are laid over each other with the directions of the grains crossed. The outermost visible layer 21a has the direction of the grain parallel to the main direction of extension of the tile.

[0068]. According to a second example (see Figures 3. and 4), a ^' tile 1 is made with a support base 3 (rubber, cork and polyurethane binging agent) having a thickness of 6mm and with an upper wooden portion 2 composed of five wooden layers (sliced oak) glued to each other with polyurethane glue. Of these five layers, the outermost visible layer 22 has a nominal thickness of 0.9mm, while the four inner layers (21a -21d) each have a nominal thickness, of 0.6mm, as illustrated in Figure 4. On completion of assembly the wooden portion 2 has an average thickness of about 3 mm. The tile 1, of a rectangular shape, measures 1250 x 195 mm and is about 9mm thick. As illustrated in Figure 2, the five wooden layers 22 and 21a - 21d, are laid over each other with the directions of the grains crossed. The outermost visible layer 22 has the direction of the grain parallel to the main direction of extension of the tile. The tile was subjected to a test of resistance to penetration (Brinell) according to UNI EN1534 : 2002. ^' HB hardness was equal to 11.67 ± 2.03 N/mm2.

[0069]. According to a third example (see Figures 5 and 6) , a tile 1 is made with a support base 3 (rubber, cork and polyurethane binging agent) having a thickness of 6mm and with an upper wooden portion 2 composed of seven wooden Layers (sliced oak) glued to each other with polyurethane glue. Of these seven layers, the outermost visible layer 22 has a nominal thickness of 0.9mm, while the six inner layers (21a -21f) each have a nominal thickness of 0.6mm, as illustrated in Figure 6. On completion of assembly the wooden portion 2 has an average thickness of about 4 mm. The tile 1, of a rectangular shape, measures 1250 x 195 mm and is about 10mm thick. As illustrated in Figure 2, the five wooden layers 22 and 21a - 21d, are laid over each other with the directions of the grains crossed. The outermost visible layer 22 has the direction of the grain parallel to the main direction of extension of the tile.

[0070] . The tile 1 made according to the aforesaid third example was subjected to a test of resistance to penetration (Brinell) according to UNI EN1534:2002. HB hardness was equal to 14.36 ± 1.72 N/mm2. The tile 1 was also subjected to experimental determination of heat conductivity λ (according to UNI EN 1745) , which proved equal to 0.156 W/ (mk) . The heat resistance R calculated was equal to 0.06496 m ^A 2K/ . The .tile 1 was subjected to measurement of the noise level from walking index L'n,w (according to UNI EN ISO 717-2: 2007), which, was ^' 54 dB with. the tile and 61 dB without the tile.

[0071] . A fourth example (not shown in the appended drawings) is relative to a tile similar to the tile mad in the third example, but having a lower portion of a thickness of 10mm. The tile 1 was subjected to measurement of the heat conductivity λ (according to UNI EN 1745) , which proved equal to 0.187 W/ (mk) . The heat resistance R calculated was equal to 0.0762 m 2K/W. The tile 1 was subjected to measurement of the noise level from walking index L'n,w (according to UNI EN ISO 717-2: 2007), which was 61 dB with the tile and 85 dB without the tile.

[0072]. The present invention relates to. a production method of a composite structure tile having an. upper wooden portion 2, having a multilayer structure _, with, a plurality of overlapping wooden layers 21 and 22, and a lower portion 3, acting as a support base and made from an agglomerate of granules in rubber and/or cork connected to each other by a polymer binding resin.

[0073] . In particular, the method according to the invention can be used to make a tile 1 having the characteristics described above.

[0074] . According to a general form of implementation, the method comprises the following operating steps:

[0075] . a) provding the aforesaid sheet-like lower portion 3 and the wooden layers 21,22; [0076] . b) applying glue to the surfaces of mutual contact of the wooden layers 21,22,

[0077]. c) placing the wooden layers 21,22 on .top of each other with the directions of the grains crossed so as. to form an assembly;

[0078] ^' . d) pressing the assembly so as to form the aforesaid upper wooden portion 2;

[0079] . e) gluing the upper wooden portion 2 to the lower, portion 3 so to obtain said tile 1.

[0080] . Advantageously, in the gluing step e) ^■ the two lower 2 and upper 3 portions are pressed together.

[0081] . According to a particularly preferred form of implementation of the method according to the invention, the ^' step d) of pressing the wooden layers 21, 22 is conducted during the step e) of gluing the upper wooden portion 2 to the lower portion 3 and involves the lower portion 3.

[0082] . In particular, the production method according to the aforesaid preferred form of implementation of the invention makes it possible to couple and connect all the components of the tile 1 to each other ( i.e. wooden layers and lower portion 3) during the same pressing cycle .

[0083] . The connection of the various components during a single pressing cycle offers a first important advantage.

[0084] . It is possible to use the support base 3 as a shock absorber during the compression of the wooden layers, exploiting its intrinsic elastic consistency. ^" During the pressing the support base adapts to the thickness of the overlaid wooden layers, compensating the diversity and unevenness of thickness present in the single wooden layers. This ensures a perfect and total gluing of the individual layers. Use of the method according to the invention thereby makes it possible to reduce to a minimum the problems deriving from uneven gluing of the surfaces.

[0085]. A second advantage is of the operative type. The performance of a single pressing cycle in fact reduces production times.

[0086]. The composite structure tile with wooden portion according to the invention thus permits several advantages to be obtained, some of which described above.

[0087] . The composite structure tile with wooden portion for coverings according to the invention has greater dimensional stability.

[0088] . The tile 1 according to the invention can be laid ^' easily, immediately and rapidly without requiring the use of glues. In the case of laying with glues, it can even be laid in conditions of considerable humidity, with plastering and grouting of the interstices between ..the tiles.

[0089]. The tile 1 can be used to make coverings,, in particular _. for floorings , associated with heating systems with less impact on heating efficiency compared to traditional tiles with wooden portions.

[0090] . The tile 1 can be used as a modular element of a heating system.

[0091] . The invention thus conceived therefore achieves the purposes stated.

[0092] . Obviously it may, in its practical embodiments, assume _. forms and configurations other than those illustrated above while remaining within the present sphere of protection.

[0093] . In addition, all the parts may be replaced with technically equivalent elements and the dimensions, ^: forms and materials used varied as needed.