Floor or wall covering panel with rigid composite core layer

Abstract

A floor or wall covering panel has a top and a bottom surface, and at least four sides, where a first and a second side include a first and a second connection profile, respectively, the first profile being configured for mechanically engaging and interlocking with the second profile of another panel, the first profile including a tongue protruding beyond the top edge of the first side, where the second profile includes a groove recessed with respect to the top edge of the second side, the groove is delimited at its bottom by a base, the panel is of laminar structure including a rigid core layer and a wear layer arranged on the core layer, where the core layer includes a first and a second sublayer of a first and a second composite material, respectively, the second sublayer being arranged atop the first sublayer, where both composite materials comprise thermoplastic material and filler material but are of different formulations, and the base delimiting the groove bottom is realized essentially within the first core sublayer.

Claims

1. A floor or wall covering panel, comprising: a top surface, a bottom surface and at least four sides, wherein a first one of the sides comprises a first connection profile and a second one of the sides comprises a second connection profile, the first and second connection profiles being arranged on opposed sides of the panel, the first connection profile being configured for mechanically engaging and interlocking with a second connection profile of another floor or wall covering panel, wherein the first side and the top surface meet at a top edge of the first side and the second side and the top surface meet at a top edge of the second side, wherein the first connection profile comprises a tongue protruding beyond the top edge of the first side, wherein the second connection profile of the floor or wall covering panel comprises a groove recessed with respect to the top edge of the second side, the groove being delimited at a bottom of the groove by a base, protruding or not beyond the top edge of the second side; wherein the floor or wall covering panel is of a laminar structure, including a rigid core layer having a modulus of elasticity, measured according to EN 310, greater than 1000 MPa, and a wear layer arranged on the core layer; wherein the core layer includes a first sublayer of a first composite material and a second sublayer of a second composite material atop the first sublayer; wherein each of the first and second composite materials comprises thermoplastic material and filler material, the first and second composite materials being of different formulations, the filler material of the first and second composite materials consisting of at least 70% by weight of mineral material; wherein the base delimiting the bottom of the groove is realized at least to 80% of a weight of the base within the first sublayer of the core layer.

2. The floor or wall covering panel as claimed in claim 1, wherein the first composite material has lower stiffness than the second composite material.

3. The floor or wall covering panel as claimed in claim 1, wherein the thermoplastic material of the first and second composite materials comprises PVC resin.

4. The floor or wall covering panel as claimed in claim 3, wherein the thermoplastic material of the first composite material comprises from 2.5% to 20% by weight of plasticizer with respect to the PVC resin.

5. The floor or wall covering panel as claimed in claim 3, wherein the thermoplastic material of the second composite material comprises no or less than 2.5% by weight of plasticizer with respect to the PVC resin.

6. The floor or wall covering panel as claimed in claim 1, wherein the thermoplastic material of the first composite material comprises from 2.5% to 20% by weight of plasticizer with respect to the PVC resin, wherein the thermoplastic material of the second composite material comprises no or less than 2.5% by weight of plasticizer with respect to the PVC resin, and wherein the ratio of the plasticizer content of the thermoplastic material of the first composite material to the plasticizer content of the thermoplastic material of the second composite material is comprised in the range from 5 to 100.

7. The floor or wall covering panel as claimed in claim 1, wherein the first and second sublayers are coextruded composite layers.

8. The floor or wall covering panel as claimed in claim 1, wherein the first and second sublayers are extruded separately and then laminated together.

9. The floor or wall covering panel as claimed in claim 1, wherein the thickness of the first sublayer amounts to between 10% and 40% of the thickness of the entire core layer.

10. The floor or wall covering panel as claimed in claim 9, wherein the thickness of the first sublayer amounts to between 10% and 33% of the thickness of the entire core layer.

11. The floor or wall covering panel as claimed in claim 1, wherein the mineral material is calcium carbonate.

12. The floor or wall covering panel as claimed in claim 1, the floor or wall covering having an overall height comprised in the range from 2.5 to 10 mm.

13. The floor or wall covering panel as claimed in claim 12, the floor or wall covering having an overall height comprised in the range from 3 mm to 6 mm.

14. The floor or wall covering panel as claimed in claim 13, the floor or wall covering having an overall height comprised in the range from 3 mm to 4.5 mm.

15. A flooring panel, comprising: a top surface, a bottom surface and at least four sides, wherein a first one of the sides comprises a first connection profile and a second one of the sides comprises a second connection profile, the first and second connection profiles being arranged on opposed sides of the panel, the first connection profile being configured for mechanically engaging and interlocking with a second connection profile of another flooring panel, wherein the first side and the top surface meet at a top edge of the first side and the second side and the top surface meet at a top edge of the second side, wherein the first connection profile comprises a tongue protruding beyond the top edge of the first side, wherein the second connection profile comprises a groove recessed with respect to the top edge of the second side, the groove being delimited at a bottom of the groove by a base, protruding or not beyond the top edge of the second side; wherein the flooring panel is of a laminar structure, including a rigid core layer having a modulus of elasticity, measured according to EN 310, greater than 1000 MPa, and a wear layer arranged on the core layer; wherein the core layer includes a first sublayer of a first composite material and a second sublayer of a second composite material; wherein each of the first and second composite materials comprises thermoplastic material and filler material, the first and second composite materials being of different formulations, the filler material of the first and second composite materials consisting of at least 70% by weight of mineral material; wherein the base delimiting the bottom of the groove is realized at least to 80% of a weight of the base within the first sublayer of the core layer; and the first composite material has lower stiffness than the second composite material.

16. The floor or wall covering panel as claimed in claim 1, wherein the base delimiting the bottom of the groove is realized entirely within the first sublayer of the core layer.

17. The floor or wall covering panel as claimed in claim 1, wherein the first and second connection profiles are machined into the first and second sides, respectively.

18. The floor or wall covering panel as claimed in claim 1, wherein the base delimiting the bottom of the groove is realized at least to 90% of a weight of the base within the first sublayer of the core layer.

19. The flooring panel as claimed in claim 15, wherein the first and second sublayers are one of: a) coextruded composite layers and b) extruded separately and then laminated together.

20. The flooring panel as claimed in claim 15, wherein the base delimiting the bottom of the groove is realized at least to 90% of a weight of the base within the first sublayer of the core layer.

21. A wallcovering panel, comprising: a top surface, a bottom surface and at least four sides, wherein a first one of the sides comprises a first connection profile and a second one of the sides comprises a second connection profile, the first and second connection profiles being arranged on opposed sides of the panel, the first connection profile being configured for mechanically engaging and interlocking with a second connection profile of another wallcovering panel, wherein the first side and the top surface meet at a top edge of the first side and the second side and the top surface meet at a top edge of the second side, wherein the first connection profile comprises a tongue protruding beyond the top edge of the first side, wherein the second connection profile comprises a groove recessed with respect to the top edge of the second side, the groove being delimited at a bottom of the groove by a base, protruding or not beyond the top edge of the second side; wherein the wallcovering panel is of a laminar structure, including a rigid core layer having a modulus of elasticity, measured according to EN 310, greater than 1000 MPa, and a wear layer arranged on the core layer; wherein the core layer includes a first sublayer of a first composite material and a second sublayer of a second composite material; wherein each of the first and second composite materials comprises thermoplastic material and filler material, the first and second composite materials being of different formulations, the filler material of the first and second composite materials consisting of at least 70% by weight of mineral material; wherein the base delimiting the bottom of the groove is realized at least to 80% of a weight of the base within the first sublayer of the core layer; and the first composite material has lower stiffness than the second composite material.

22. The wallcovering as claimed in claim 21, wherein the first and second sublayers are one of: a) coextruded composite layers and b) extruded separately and then laminated together.

23. The wallcovering panel as claimed in claim 21, wherein the base delimiting the bottom of the groove is realized at least to 90% of its weight within the first sublayer of the core layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) By way of example, preferred, non-limiting embodiments of the invention will now be described in detail with reference to the accompanying drawings, in which:

(2) FIG. 1: is a schematic cross-sectional view of a first connection profile of a flooring panel according to a preferred embodiment of the invention;

(3) FIG. 2: is a schematic cross-sectional view of a second connection profile of the flooring panel, complementary to the connection profile of FIG. 1;

(4) FIG. 3: is a schematic cross-sectional view of the first connection profile according to a variant of the flooring panel of FIG. 1;

(5) FIG. 4: is a schematic cross-sectional view of the second connection profile according to the variant of the flooring panel of FIG. 1;

(6) FIG. 5: is an illustration of how much the height of the first core sublayer can be varied according to a preferred aspect of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

(7) FIGS. 1 and 2 show a flooring panel 10 according to a first preferred embodiment of the invention. The flooring panel 10 has a having a top surface 12, a bottom surface 14 and at least four sides. FIG. 1 shows a first one of the sides in more detail, while FIG. shows the complementarily shaped opposite side 18 (called herein “the second side”). The first side 16 comprises a first connection profile featuring a tongue 20 and the second side 18 comprises a second connection profile featuring a groove 22. The first and second connection profiles are configured for mechanically engaging and interlocking with a second and a first connection profile, respectively, of another flooring panel of the same type.

(8) The edge 26 where the first side 16 and the top surface 12 meet is hereinafter called the first top edge and the edge 26 where the second side 18 and the top surface 12 meet is hereinafter called the second top edge. When two flooring panels are connected at their first and second connection profile, respectively, the corresponding first and second top edges come to lie adjacent each other.

(9) The tongue of the first connection profile protrudes beyond (as “seen” from the panel 10) the first top edge 24, whereas the groove 22 of the second connection profile is recessed with respect to the second top edge 26. The tongue 20 and groove 22 are complementarily shaped, so as to enable a tongue-and-groove connection between neighboring panels. The groove 22 is delimited at its bottom by a base 28. In the illustrated embodiment, the base 28 protrudes beyond (as “seen” from the panel 10) the second top edge 26, but whether the extremity of the base 28 protrudes or is recessed with respect to the second top edge depends on the geometrical configuration of the first and second connection profiles.

(10) The flooring panel 10 is of a layered structure and includes a rigid core layer 30 and a wear layer 32 arranged on the core layer. In the illustrated embodiment, the core layer 30 and the wear layer 32 sandwich a decorative layer 34 (e.g. a print layer). The wear layer 32 is in this case transparent or translucent, so that the décor is apparent to the users. The decorative layer 34 could comprise a dedicated printing substrate carrying one or more ink layers. Alternatively, the decorative layer could consist of ink layer(s) printed directly on the backside of the wear layer 32 or the top side of the core layer 30.

(11) The core layer 30 comprises a first sublayer 36 of a first composite material and a second sublayer 38 of a second composite material atop the first sublayer 36. The first and second composite materials comprise thermoplastic material, in particular PVC resin, and filler material but are of different formulations, which give them different mechanical properties, in particular different stiffness.

(12) The base 28 delimiting the bottom of the groove 22 is realized essentially (e.g. to at least to 80% of its weight or to at least to 90% of its weight or entirely) within the first sublayer 36 of the core layer 30. The weight of the base 28 herein means the weight of the part of the core layer 30 that extends below the groove 22 between the inner extremity of the groove 22 and the outer extremity of the base 28 (i.e. over length L.sub.B in FIG. 2). The weight of the base 28 can thus be determined experimentally by cutting the base 28 along the line 40 and weighting the part thus obtained. The proportion of the base 28 realized in the first sublayer 36 can then be determined by cutting the base 28 at the interface 42 between the first and second sublayers 36, 38 and weighting the fragments belonging to the first or second sublayer.

(13) In the illustrated embodiment, the formulations of the first and second sublayers are selected in such a way that the first (lower) sublayer 36 has a lower stiffness than the second sublayer 38. Accordingly, the first sublayer 36 bends or otherwise yields more easily under load, reducing the susceptibility of base 28 to breaking. Experiments showed that flooring made of rigid synthetic floor panels (not glued to the underfloor) according to this embodiment exhibited less breakage in so-called castor-chair tests than floor panels having a core layer consisting entirely of the stiffer material.

(14) The thickness H.sub.1 of the first sublayer 36 amounts to a value within the range from 10% to 40% of the thickness H.sub.C of the core layer 30. More preferably, the value of H.sub.1 is situated in the range from 15% to 33% of H.sub.C. It should be noted that the drawings are not to scale.

(15) The flooring panel 10 has an overall height H.sub.tot in the range from 2.5 to 10 mm, preferably in the range from 3 mm to 6 mm, and most preferably in the range from 3 mm to 4.5 mm. The invention is particularly interesting for thin rigid flooring panels having a height of 5 mm or less, e.g. 4.5 mm or less, or 4 mm or less, or 3.5 mm or less, or 3.2 mm or less.

(16) FIGS. 3 and 4 show a flooring panel 10 according to a second preferred embodiment of the invention. With respect to the embodiment of FIGS. 1 and 2, the difference is that the core layer 30 comprises three sublayers 36, 37, 39 instead of two. Apart from that, the flooring panel of FIGS. 3 and 4 is substantially identical to the one of FIGS. 1 and 2. For the sake of brevity, only the differences will be discussed hereinafter. The reader may refer to the description of FIGS. 1 and 2 for explanations regarding the other aspects of the flooring panel.

(17) The core layer 30 comprises a first sublayer 36 of a first composite material, a second sublayer 37 of a second composite material atop the first sublayer 36 and a third sublayer 39 of the first composite material atop the second sublayer 37. The first and second composite materials comprise thermoplastic material, in particular PVC resin, and filler material but are of different formulations, which give them different mechanical properties, in particular different stiffness.

(18) FIG. 5 illustrates that the height of the first sublayer can be varied. The thickness H.sub.1 of the first sublayer amounts to at most 40% of the core layer thickness H.sub.C. At the same time, a substantial part of the base 28 delimiting the bottom of the groove 22 is realized essentially within the first sublayer 36 of the core layer 30. Therefore, as illustrated in FIG. 5, the height H.sub.1 may be varied between an upper bound 44 (corresponding to 0.4×H.sub.C) and a lower bound 46 (corresponding to the height below which less than 80% of the weight of the base consists of the material of the first sublayer). The interface 42 between the first and second sublayers therefore lies within a corridor 48 delimited by bounds 44 and 46.

(19) Examples of flooring panels in accordance with preferred embodiments of the invention are indicated in the tables below.

(20) TABLE-US-00001 TABLE 1 Amount (wt % Layer Formulation w.r.t. layer) Height Wear layer PVC 90 0.2 mm plasticizer 5 additives 5 Décor layer Compatible inks printed on 100 <20 μm backside of wear layer Upper core PVC 45 2 mm sublayer plasticizer 9 Filler (CaCO.sub.3) 42 Additive (processing aid) 4 Lower core PVC 54 1.9 mm sublayer plasticizer 0.5 Filler (CaCO.sub.3) 40.5 Additive (processing aid) 5

(21) TABLE-US-00002 TABLE 2 Amount (wt % Layer Formulation w.r.t. layer) Height Wear layer PVC 95 0.2 mm additives 5 Upper core PVC 46 1.8 mm sublayer plasticizer 3 Filler (CaCO.sub.3) 45 Additive (processing aid) 6 Lower core PVC 55 1.7 mm sublayer Filler (CaCO.sub.3) 40 Additive (processing aid) 5

(22) TABLE-US-00003 TABLE 3 Amount (wt % Layer Formulation w.r.t. layer) Height Wear layer PVC 92 0.2 mm Corundum particles 3 additives 5 Décor layer Printing substrate carrying 100 Approx.: compatible inks 100 μm Upper core PVC 40 1.8 mm sublayer plasticizer 5 Filler (CaCO.sub.3) 48 Additive (processing aid) 7 Lower core PVC 43 1.7 mm sublayer plasticizer 1 Filler (CaCO.sub.3) 50 Additive (processing aid) 6

(23) TABLE-US-00004 TABLE 4 Amount (wt % Layer Formulation w.r.t. layer) Height Wear layer PVC 92 0.2 mm Corundum particles 3 additives 5 Décor layer Printing substrate carrying 100 Approx.: compatible inks 100 μm Upper core PVC 42 0.9 mm sublayer plasticizer 0.5 Filler (CaCO.sub.3) 52 Additive (processing aid) 5.5 Middle core PVC 40.5 1.2 mm sublayer plasticizer 4.5 Filler (CaCO.sub.3) 49 Additive (processing aid) 6 Lower core PVC 42 0.9 mm sublayer plasticizer 0.5 Filler (CaCO.sub.3) 52 Additive (processing aid) 5.5

(24) While specific embodiments and examples have been described herein in detail, those skilled in the art will appreciate that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof.