Floor panel and method for manufacturing the same

Abstract

A floor panel includes a core and decorative layer applied thereon, such that the material of the aforementioned core has a density of more than 1000 kg/m.sup.3, preferably more than 1300 kg/m.sup.3, and has a thickness of 6 millimeters or more. The core has internal spaces and/or that the core has spaces on its bottom side. A method for manufacturing such floor panels is provided according to the aforementioned floor panel.

Claims

1. A floor panel having a rectangular shape with a pair of long opposite edges and a pair of short opposite edges, the floor panel comprising a core and a decorative layer which is applied thereon, wherein material of the aforementioned forming the core is a plastic composite comprising thermoplastic material and at least 40 weight percent of filler, wherein the material has a density of more than 1000 kg/m.sup.3; wherein the thermoplastic material is polyvinyl chloride, polypropylene, polyethylene or polyethylene terephthalate, and said filler has a greater specific weight than the thermoplastic material; wherein the decorative layer comprises a printed thermoplastic film showing a pattern and a thermoplastic plastic layer situated on top of the pattern; wherein the core forms one or more spaces on a bottom side thereof; wherein the floor panel is provided, on the pair of long opposite edges and on the pair of short opposite edges, with mechanical coupling parts arranged for coupling two of such floor panels to each other at respective sides, an interlocking is arranged to be produced in a coupled state of two of such floor panels, at least in a direction at right angles to the respective sides and in a plane of the floor panels; wherein the mechanical coupling parts comprise a male coupling part and a female coupling part that cooperate with each other in said coupled state; wherein the female coupling part is provided with a lip projecting beyond an associated top edge and wherein the lip is provided with a locking element in the form of an upright portion at a top side of the lip which can cooperate with a locking element on the bottom side of the male coupling part, in the form of a space in the bottom side of the male coupling part; wherein in the coupled state at least horizontally active locking surfaces are produced on the locking elements; wherein the bottom of the lip comprises one or more of the spaces; wherein the one or more of the spaces has a depth such that the one or more of the spaces remains completely below the top side of the lip.

2. The floor panel of claim 1, wherein the thermoplastic material is polyvinylchloride having a plasticizer content of 5phr or less or even without plasticizer.

3. The floor panel of claim 1, wherein the spaces result in a weight reduction of the core of at least 15%.

4. The floor panel of claim 1, wherein a cork layer or a synthetic foam layer is provided on the bottom side of the core.

5. The floor panel of claim 4, wherein said cork layer or synthetic foam layer is continuous along said bottom of said lip.

6. The floor panel of claim 1, wherein the spaces extend continuously from one side of the floor panel to another side of the floor panel.

7. The floor panel of claim 1, wherein the the spaces extend in a length direction of the floor panel.

8. A method for manufacturing floor panels, wherein each floor panel of the floor panels has a rectangular shape with a pair of long opposite edges and a pair of short opposite edges, the floor panel comprising a core and a decorative layer which is applied thereon, and the method at least comprises the step of consolidating a material of the core, wherein the material to be consolidated has internal spaces and/or wherein the material to be consolidated has one or more spaces on its bottom side; wherein the material forming the core is a plastic composite comprising thermoplastic material and at least 40 weight percent of filler, wherein the material has a density of more than 1000 kg/m.sup.3; wherein the thermoplastic material is polyvinyl chloride, polypropylene, polyethylene or polyethylene terephthalate, and said filler has a greater specific weight than the thermoplastic material; wherein the decorative layer comprises a printed thermoplastic film showing a pattern and a thermoplastic plastic layer situated on top of the pattern; wherein the floor panel is provided, on the pair of long opposite edges and on the pair of short opposite edges, with mechanical coupling parts arranged for coupling two of such floor panels to each other at respective sides, whereby an interlocking is arranged to be produced in a coupled state of two of such floor panels, at least in a direction at right angles to the respective sides and in a plane of the floor panels; wherein the mechanical coupling parts comprise a male coupling part and a female coupling part that cooperate with each other in said coupled state; wherein the female coupling part is provided with a lip projecting beyond an associated top edge and wherein the lip is provided with a locking element in the form of an upright portion at a top side of the lip which can cooperate with a locking element on the bottom side of the male coupling part, in the form of a space in the bottom side of the male coupling part; wherein in the coupled state at least horizontally active locking surfaces are produced on the locking elements; wherein the bottom of the lip comprises one or more of the spaces; wherein the one or more of the plurality of spaces has a depth such that one or more of the spaces remains completely below the top side of the lip.

9. The method of claim 8, wherein the material to be consolidated comprises a scattered bed of granulates, powders, fibers or other particles and/or wherein the material to be consolidated comprises an extruded material and/or wherein the material to be consolidated comprises a slurry.

10. The method of claim 9, wherein the material to be consolidated comprises a scattered bed of granulates, powders, fibers or other particles and/or a slurry, wherein the material to be consolidated is arranged on a mold or wherein the material to be consolidated is arranged on a structured conveying element.

11. The method of claim 9, wherein the material to be consolidated comprises an extruded material, wherein the material to be consolidated is formed by extrusion using a T-die, wherein a slit which is situated on the side forming the bottom side of the core is comb-like.

12. The method of claim 9, wherein the material to be consolidated comprises an extruded material, wherein the material to be consolidated is formed by extrusion using at least two dies, wherein a die which forms the bottom side of the core extrudes an amount of material which varies transversely to an extrusion direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In order to show the features of the invention in more detail, some preferred embodiments are described below by way of example and without being limited thereto, with reference to the accompanying drawings, in which:

(2) FIG. 1 shows a floor panel comprising the features of the invention;

(3) FIG. 2 shows a cross section on an enlarged scale along the intersecting line II-II illustrated in FIG. 1;

(4) FIG. 3 shows a cross section on an even larger scale along the intersecting line III-III illustrated in FIG. 1;

(5) FIG. 4 shows a variant from the same view;

(6) FIGS. 5 to 8 show variants in a view similar to that of FIG. 2;

(7) FIG. 9 shows a cross section of the floor panel from FIG. 8 in a view along the intersecting line III-III illustrated in FIG. 1;

(8) FIG. 10 diagrammatically shows a method having the features of the second aspect of the invention;

(9) FIG. 11 shows a cross section on an enlarged scale along the intersecting line XI-XI illustrated in FIG. 10;

(10) FIG. 12 shows a variant from the same view;

(11) FIG. 13 diagrammatically shows another method having the features of the second aspect of the invention;

(12) FIG. 14 shows a cross section on an enlarged scale along the intersecting line XIV-XIV illustrated in FIG. 13;

(13) FIG. 15 shows a variant from the same view.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

(14) FIG. 1 shows a floor panel 1 having the features of the invention. In this case, this involves a rectangular floor panel 1 having a pair of long opposite edges 2-3 and a pair of short opposite edges 4-5.

(15) FIG. 2 shows that the floor panel 1 has a core 6 and a decorative layer 7 applied thereon. The core material has a thickness T of more than 6 millimeters, in those case even more than 10 millimeters, namely approximately 12 millimeters. The material of the core 6 has a density of more than 1000 kg per cubic meter, and in this case even of more than 1300 kg per cubic meter. The material of the core 6 involves, in particular, a plastic composite which comprises a thermoplastic material and filler. The thermoplastic material is polyvinylchloride (PVC) having a plasticizer content of less than 5 phr (5 parts per 100 parts of thermoplastic material or PVC). The content of fillers in the core is more than 40% by weight, in this case between 65 and 87% by weight, namely approximately 80% by weight.

(16) FIG. 2 furthermore clearly shows that the core material 6 has spaces 9 on its bottom side 8. In this case, the aforementioned spaces 9 extend continuously from the one short edge 4 to the other short edge 5 of the floor panel 1, namely in the length direction L of the rectangular floor panel 1. A synthetic foam layer 10 is provided, for example made of physically or chemically crosslinked polyethylene, on the bottom side 8 of the core 6.

(17) Here, the decorative layer 7 is substantially composed of thermoplastic material, more particularly from PVC, and comprises a printed thermoplastic film 11 which forms a decoration 12 comprising a pattern of wood. Above the aforementioned pattern 12, a transparent thermoplastic plastic layer 13, likewise made of PVC, is present.

(18) The long edges 2-3 of the floor panel 1 are provided with mechanical coupling means 14 which allow two of such floor panels 1 to be coupled to each other by the respective edges 2-3. In the coupled state, a mutual interlocking between the respective edges 2-3 is produced, both in a horizontal direction H at right angles to the long edges 2-3 and in the plane of the floor panels 1, as in a vertical direction V at right angles to the plane of the floor panels 1. The coupling means 14 are substantially configured in the form of a tongue 15 and groove 16 and may be joined together at least by means of a turning movement W about the respective edges 2-3.

(19) The depth D of the spaces 19 is constant, or at least still virtually constant along the entire length of the spaces 19, and is less than half the thickness T of the core material 6, and preferably between 15 and 40% of the thickness T of the core material 6.

(20) FIG. 3 shows that the short sides 4-5 of the floor panel 1 are also provided with coupling means 14. The coupling means 14 on the short pair of edges 4-5 comprise a male coupling part 17 and a female coupling part 18 which can cooperate with each other. In the example, both the male coupling part 17 and the female coupling part 18 are made entirely from the material of the floor panel 1. The female coupling part 18 is provided with a lip 19 which projects beyond the associated top edge 20 and wherein this lip 19 is provided with a locking element in the form of an upright portion 21 which can cooperate with a locking element on the bottom side of the male coupling part 17, in the form of a space 22 in the bottom side of the male coupling part 17. In the coupled state, at least horizontally active locking surfaces 23-24 are produced on the aforementioned locking elements 21-22.

(21) It will therefore be clear that the example also has the features of the particular independent aspect of the invention mentioned in the introduction.

(22) FIG. 3 furthermore clearly shows that the aforementioned spaces 19 extend into the short edge 5 comprising the female coupling part 18. In the present case, the spaces 19 extend into the short edge 5 comprising the female coupling part 18, and into the short edge 4 comprising the male coupling part 17. At the location of the respective edge 4-5, the respective space 9 has a depth D which is such that at least a portion of the aforementioned horizontally active surfaces 23-24 is retained on the locking element at the location of the respective space 9, wherein at least 50% of the height H1 of the horizontally active contact surface 23-24 is retained at the location of the space 9, and in this case even 80% or more.

(23) In the example from FIG. 3, the respective horizontally active contact surfaces 23-24, viewed from the bottom to the top, are inclined in the direction of the associated top edge 20. In this case, the deviation from the vertical is preferably 2 to 10. As a result thereof, the same surfaces 23-24 also serve as vertically active contact surfaces. It will be clear that the above-described measure of the reduced depth D of the one or several spaces 19 also results in the advantage that at least the same portion of the height H1 of these vertically active surfaces is retained. In addition to these vertically active contact surfaces, the female coupling part 17 and the male coupling part 18, on a proximal wall 25 of the female coupling part 17, have further vertically active locking surfaces 26-27 which, in the example, are completely preserved since they are situated completely above the level of the space 9.

(24) It should be noted that, in the context of the particular aspect mentioned in the introduction, it is also possible for the depth D of the space 9 to be such that it is entirely on a level under the upwardly directed groove of the female coupling part 17, and thus does not, or hardly, interfere with the satisfactory performance of the coupling means 14 on the short edges 4-5. This is illustrated by means of the dashed line 28. According to another possibility, the depth D of the space 9 is such that it is positioned under the lowest contact surface 29 between the male coupling part 17 and the female coupling part 18, without necessarily having to be on a level under the upwardly directed groove. This is illustrated by means of the dashed line 30.

(25) FIG. 4 shows a variant in which this coupling part 17, in addition to the vertically active contact surfaces formed on the projecting lip 19 of the female coupling part 17, has further vertically active locking surfaces 26-27 on a distal wall 31, namely on the distal wall of the aforementioned lip 19. In the illustrated case, the additional vertically active locking surfaces 26-27 at the location of the space 9 are not preserved, whereas at least 50% of the height H1 of the vertically active locking surfaces and the horizontally active locking surfaces 23-24 is preserved at the location of the upright portion 21 of the lip 19. It goes without saying that, also in this example, the level of the space 9 can be adjusted in accordance with the dashed lines 28-30, as defined by means of the description of FIG. 3.

(26) FIG. 5 shows a variant in which the core material 6 is provided with spaces 9A on its top side 32 as well, similar to the spaces 9 formed on the bottom side 8 of the core material 6. In such a case, the decorative layer 7 preferably comprises a rigid layer 33, as is the case here, namely having a rigidity higher than the rigidity of the other portion of the decorative layer 7. In this case, this may be a layer which extends under a printed support or film 11, as is the case here. In the case of a decorative layer 7 composed of thermoplastic material, the aforementioned rigid layer 33 preferably likewise consists of thermoplastic material, but preferably, in the case of PVC, with a lower plasticizer content or without plasticizer, compared to the other portion of the decorative layer 7. The rigid layer 33 makes it possible for the spaces 9A on the top side 32 of the core 6 to be bridged more efficiently, namely with a reduced risk of collapse at the location of the spaces 9A.

(27) It will be clear from the above that bridging spaces 9A on the top side 32 by means of the decoration layer 7 as such has inventive merits. According to a second particular independent aspect, the invention therefore also relates to a floor panel 1 comprising a core 6 and a decorative layer 7 applied thereon, wherein the material of the aforementioned core 6 has a density of more than 1000 kg/m.sup.3, preferably more than 1300 kg/m.sup.3, and/or wherein the aforementioned core has a thickness T of 6 millimeters or more, characterized by the fact that the core 6 has spaces 9A on its top side 32 and the decorative top layer 7 is chosen from the following: a decorative top layer 7 which contains a wood layer having a thickness of more than 1 millimeter, for example 2.5 millimeters or more; a decorative top layer 7 which comprises a stone, a ceramic or a mineral-based layer having a thickness of more than 1 millimeter, for example 3 millimeters or more; a decorative top layer which comprises a plastic layer having a thickness T1 of 1 millimeter or more; the plastic layer may, for example, be PVC with a plasticizer content of less than 1 phr; in such a case, the plastic layer preferably also has a decoration 12, for example applied as a printed thermoplastic film 11 and a transparent wear layer 13, preferably also thermoplastic. FIG. 5 gives an example thereof, with the aforementioned plastic layer being formed by the abovementioned rigid layer 33.

(28) FIG. 6 gives an example which substantially corresponds to the example from FIGS. 1 to 3, but with the spaces 9 being filled with a material which has a density of less than 500 kg/m.sup.3. In this case, this involves the same material as the aforementioned synthetic foam layer 10.

(29) FIG. 7 shows an embodiment which substantially corresponds to the example from FIGS. 1 to 3, but wherein the core material 6 as such is composed from several layers 6A-6B-6C, namely comprising a central foamed PVC layer 6A, flanked above and below by a non-foamed or less foamed PVC layer 6B-6C. In the example, the layers are separated by glass-fiber layers 34, preferably of the non-woven type. The spaces 9 extend into the foamed PVC layer 6A.

(30) FIGS. 8 and 9 show an embodiment which corresponds substantially to the example of FIGS. 1 to 3. However, FIGS. 8 and 9 show some particular features which may each be used separately or in combination in other embodiments.

(31) A first particular feature consists in the fact that the depth D of the spaces 9 is such that they remain completely below the level 35 of the bottom side of the tongue 15 or coincide or virtually coincide therewith. Preferably also, as is the case here, the depth of the spaces 9 is such that they remain completely below the level 36 of the top side of bottom groove lip 37 or coincide or virtually coincide therewith.

(32) A second particular feature consists in the fact that the distance A between two spaces 9 at the location of the bottom groove lip 37 is at least 80% of the length L1 of the aforementioned bottom groove lip 37, and/or at least 130% of the length L2 of the portion of the bottom groove lip 37 which projects beyond the upper groove lip 38 in horizontal direction H. Preferably, the distance A between every two adjacent spaces is as large as or virtually as large as, namely in each case at least 80% of the length L1 of the bottom groove lip 37 and/or at least 130% of the length L2 the projecting portion of the bottom groove lip 37.

(33) By using a combination of the first and second features, it is possible to select the position of tongue 15 and groove 16 independently from the core material.

(34) Preferably, a core material 6 is manufactured, for example in the way of the second independent aspect, having spaces 9 which comply with the first and/or the second particular feature. Such core material 6 may therefore be used for producing a floor panel 1 comprising coupling means 14. The production and action of the coupling means 14 will not, or hardly, be disrupted by using the first and/or the second particular feature.

(35) A third particular feature, here illustrated by dashed line 39, consists in the fact that spaces 9A are formed at the top surface 32 of the core material 6. These may be present separately or may be present in combination with the spaces 9 on the bottom side 8 of the core 6. In the latter case, the spaces 9A at the top surface 33 are preferably, as is illustrated here by the dashed line 39, situated directly opposite the spaces 9 on the bottom side 8 of the core material 6. However, it is not excluded that the spaces 9A at the top surface 33 would be offset with respect to the spaces 9 on the bottom side 8, for example positioned in the middle between two spaces 9 on the bottom side 8. The spaces 9A at the top surface 33 preferably have a depth D which is such that they are positioned completely above the bottom side 40 of upper groove lip 38.

(36) It should furthermore be noted that in the example from FIGS. 8 and 9, the same or at least similar coupling means 14 are used along the short edges 4-5 as along the long sides 2-3. This is not necessarily the case.

(37) Furthermore, the example from FIGS. 8 and 9 also has the properties of the particular independent aspect mentioned in the introduction. In addition, the spaces 9 on the edges 4-5 have a depth D which is such that at least a portion of the horizontally active surfaces 23-24 on the locking element, namely the upright portion 21A of the bottom groove lip 37 and the space 22A on the bottom side of the tongue 15, is retained at the location of the respective space 9.

(38) FIG. 10 diagrammatically shows some steps in a method comprising the features of the second aspect of the invention. The example from FIG. 10 is based on a material to be consolidated 41 in the form of a bed of granulates 42. In this case, the granulates 42 are scattered on a conveyor belt 43 by means of several scattering devices 44. Consolidation takes place between the belts 45 of a pressing device 46.

(39) FIG. 11 shows that the aforementioned conveyor belt 43 is structured in accordance with the desired spaces 9 in the core material 6. Thus, the conveyor belt 43 forms a mold. After consolidation, a core material 6 is obtained which is similar to that illustrated in FIGS. 8 and 9.

(40) FIG. 12 shows an alternative in which elements 47 are provided on a generally flat or only lightly textured conveyor belt 43 which correspond to the desired spaces 9 in the core material 6. The elements 47 may be strip-shaped, as is the case here, but may also be mutually connected, for example as a result of the fact that they are situated on a common base sheet, as is indicated by means of the dashed line 48. According to an embodiment which is not shown the aforementioned elements may have been produced by means of extrusion, for example in-line extruded, by means of one or several extruding devices upstream from the aforementioned scattering devices 44. In such a case, the aforementioned elements preferably continue to form part of the final core material 6 and they have a density of 500 kg/m.sup.3 or less. In other words, in this way, an embodiment may be produced which is similar to that of FIG. 6.

(41) FIG. 13 shows another method comprising the features of the second aspect of the invention. The material to be consolidated 41 is in this case extruded, more particularly the extruded material is obtained by means of at least two dies 49-50, wherein the die 50 which forms the bottom side 8 of the core 6 deposits an amount of material which varies transversely to the extrusion direction E. In the illustrated example, consolidation takes place between rollers 51, but may also take place between pressing bands or calibrated stationary press plates.

(42) FIG. 14 shows the material to be consolidated 41. In this case, the varying amount of material has been obtained by means of a die 50 which is alternately closed and open in accordance with the desired spaces 9.

(43) FIG. 15 shows an alternative, wherein the varying amount of material has been obtained by means of a T-die 50 which is configured to be comb-like on one side in accordance with the desired spaces 9. FIG. 15 furthermore shows that a material layer 52 can also be extruded at the top side 32A of the material to be consolidated 41, here at the bottom in FIG. 15, with a view to producing a balanced sandwich construction.

(44) The present invention is by no means limited to the above-described embodiments, but such floor panels and methods for the production thereof can be achieved without departing from the scope of the present invention.