RIGID PANEL FOR MAKING A FLOOR COVERING

Abstract

The disclosure relates to a multilayer panel for producing a floor covering, comprising a wear layer bonded to a back layer, said back layer being made up of at least a thermoplastic material, a plasticizer and fillers, the wear layer comprising a surface layer made up at least of PVC, said surface layer having a Shore D hardness greater than or equal to 60 and a Young's modulus greater than or equal to 1000 MPa.

Claims

1. A multilayer panel for making a floor covering comprising, a wear layer bonded to a back layer, wherein the back layer is derived from at least a thermoplastic material, a plasticizer and fillers, wherein the wear layer comprises a surface layer derived from at least polyvinyl chloride (PVC), the surface layer having a Shore D hardness greater than or equal to 60 and a Young's modulus greater than or equal to 1000 MPa.

2. The panel according to claim 1, wherein the surface layer has a Shore D hardness greater than or equal to 70.

3. The panel according to claim 1, wherein the surface layer has a Young's modulus greater than or equal to 1500 MPa.

4. The panel according to claim 1, wherein the surface layer is transparent.

5. The panel according to claim 1, wherein the surface layer comprises impact absorbers.

6. The panel according to claim 5, wherein the impact absorbers are present in an amount of less than 25%, by weight of the surface layer.

7. The panel according to claim 5, wherein the impact absorbers are present in an amount of between 2.5% and 15%, by weight of the surface layer.

8. The panel according to claim 5, wherein the impact absorbers are elastomeric polymeric particles.

9. The panel according to claim 5, wherein the impact absorbers are polymeric plasticizers.

10. The panel according to claim 1, wherein a composition of the surface layer has a glass transition temperature (Tg) between 60° C. and 80° C.

11. The panel according to claim 10, wherein the composition has a glass transition temperature (Tg) between 70° C. and 80° C.

12. The panel according to claim 1, wherein a composition of the surface layer comprises at least one liquid plasticizer present in an amount of less than 10%, by weight of the surface layer.

13. The panel according to claim 12, wherein the liquid plasticizer is present in an amount of less than or equal to 5% by weight of the surface layer.

14. The panel according to claim 1, wherein the surface layer has a thickness of between 0.1 and 3 mm.

15. The panel according to claim 1, wherein the surface layer has a thickness of between 0.3 and 2.5 mm.

16. The panel according to claim 1, wherein the surface layer has a thickness of between 5 and 30% of the total thickness of the panel.

17. The panel according to claim 1, wherein the back layer comprises a balancing layer derived from at least PVC.

18. The panel according to claim 17, wherein the balancing layer has a Shore D hardness greater than or equal to 50 and a Young's modulus greater than or equal to 500 MPa.

19. The panel according to claim 17, wherein the balancing layer is bonded to the wear layer.

20. The panel according to claim 19, wherein the wear layer comprises a decorative film, the decorative film being in contact with the balancing layer.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0058] Other features and advantages will emerge better from the following description, provided as a non-limiting example, in reference to the appended figures, in which:

[0059] FIG. 1 schematically illustrates a sectional view of a floor covering according to the disclosure, the wear layer of which comprises at least one rigid surface layer.

[0060] FIG. 2 shows a schematic sectional view of an alternative floor covering according to the disclosure.

[0061] FIG. 3 schematically illustrates a sectional view of an alternative floor covering according to the disclosure, the wear layer of which comprises at least one balancing layer obtained from PVC.

[0062] FIG. 4 schematically illustrates a sectional view of an alternative floor covering according to the disclosure, the wear layer of which comprises at least one balancing layer obtained from PVC.

[0063] FIG. 5 schematically illustrates a sectional view of an alternative floor covering according to the disclosure, the wear layer of which comprises at least one balancing layer obtained from PVC.

[0064] FIG. 6 schematically illustrates a sectional view of an alternative floor covering according to the disclosure, the wear layer of which comprises at least one balancing layer obtained from PVC.

DETAILED DESCRIPTION

[0065] In reference to FIG. 1, the floor covering (1) according to the disclosure comprises: [0066] a wear layer (2), comprising a rigid surface layer (4) having a Shore D hardness greater than or equal to 60 and a Young's modulus greater than or equal to 1000 MPa and a decorative layer (2a); [0067] a back layer (3).

[0068] The decorative layer (2a) may in particular consist of a decorative film that may be obtained from a PVC film printed on one of said faces. Known printing techniques are in particular rotogravure. Alternatively, the decorative layer (2a) may also be obtained from pellets made from PVC, then pressed, by plastisol coating, by flat die extrusion or by calendaring.

[0069] In general, a back layer (3) traditionally made from plasticized flexible PVC may be obtained with a composition comprising about 30% by weight of PVC, about 10% by weight of plasticizers, about 5% by weight of additives (process aids, stabilizers, pigments) and about 55% by weight of fillers.

[0070] The back layer (3) is for example made up of a first layer made from PVC (3a) intended to be bonded to the wear layer (2), a second layer (3c) and a reinforcement (3b) bonded between the first layer (3a) and the second layer (3c). The layers (3a) and (3c) are for example obtained from filled plasticized PVC and formed by calendaring. The back layer (3) may also be obtained by pressing pellets manufactured from PVC, by coating with plastisol, or by flat die extrusion. Producing this layer by calendaring nevertheless remains its favored manufacturing method in terms of cost and resulting mechanical performance.

[0071] Alternatively and in reference to FIG. 2, the floor covering (1) according to the disclosure comprises a first reinforcement (3b) and a second reinforcement (3d), for example in the form of two fiberglass grids.

[0072] Particularly and in reference to FIGS. 3, 4 and 5, the back layer (3) may comprise at least a first balancing layer (3e) made from PVC. In a first alternative, according to FIG. 3, said balancing layer is arranged in the lower part of the back layer (3), such that one face of the balancing layer (3e) is in contact with the floor.

[0073] Alternatively, said balancing layer (3e) can be arranged in the upper part of the back layer (3), as illustrated in FIG. 4, such that a face of the balancing layer (3e) is in contact with the wear layer (2). This position of the balancing layer advantageously makes it possible to eliminate the reinforcement while retaining the good dimensional stability characteristics. This position also makes it possible to decrease the thickness of the rigid surface layer (4) while retaining very good mechanical properties as well as good resistance to indentation, scratching and scraping, while decreasing the manufacturing cost of the floor covering.

[0074] Alternatively and in reference to FIG. 5, the back layer (3) may comprise at least a first balancing layer (3e) and a second balancing layer (3f) made from PVC. The balancing layers (3e, 3f) are respectively arranged in the lower and upper part of the back layer (3). The first balancing layer (3e) may in particular be bonded to the wear layer (2). The second balancing layer (3f) may in particular be arranged to be in contact with the floor. This particular configuration in particular makes it possible to obtain a balanced and dimensionally stable back layer (3), without having to add a reinforcement.

[0075] With the aim of obtaining a particularly stable back layer (3), the latter may also be made up of a single balancing layer obtained from PVC.

[0076] In reference to FIG. 6, the floor covering (1) according to the disclosure may also comprise: [0077] a wear layer (2), comprising a rigid surface layer obtained from PVC (4) and a decorative layer (2a) [0078] a back layer (3), comprising a balancing layer (3e) arranged in the central position and obtained from PVC and bonded between a first back layer (3a) and a second back layer (3c) that are traditionally obtained from plasticized and filled flexible PVC.

[0079] In this example, the balancing layer (3e) makes it possible to improve the dimensional stability and the scraping of the obtained floor covering without needing to use a reinforcement such as a glass web.

EXAMPLES

Examples 1 to 3

[0080] Tiles according to FIG. 2 are manufactured.

[0081] These tiles are obtained by static pressing (3 minutes of heating at 180° C. and bars followed by 4 minutes of cooling under 10 bars) of: [0082] A back layer (3), comprising two layers obtained from plasticized and shaded flexible PVC pellets (3a and 3c), said pellets being manufactured beforehand by compounding; [0083] Two reinforcing glass grids (3b and 3d) of about 50 g/m.sup.2 (68 tex, 200 μm thick) intercalated between the two layers (3a, 3c) and between the back layer (3) and the wear layer (2). [0084] A wear layer (2) comprising a printed decorative PVC film (2a) on which a 2 mm transparent rigid surface layer (4) made from PVC is laminated.

[0085] After cooling to ambient temperature, these tiles are covered with a thin layer of acrylate-based varnish (not shown) of about 25 g/m.sup.2, on a coating line.

[0086] The pellets making up the backing sub-layers (3a and 3c) comprise the following ingredients, expressed in percentages by weight: 41% PVC, 16% plasticizer (DINP), 2% additives (process aids, thermal stabilizers, pigments) and 41% calcium carbonate (CaCO.sub.3). The characteristics of the backing sub-layers (3b, 3d) are summarized in table 2.

[0087] The transparent surface layer (4) is in turn obtained by calendaring a dry blend of a rigid PVC-based formula. Three transparent surface layers are obtained from rigid PVC (CU 1, CU 2, CU 3) according to the disclosure as well as a traditional reference surface layer (CU REF). The compositions of the layers (CU 1, CU 2, CU 3 and CU REF) are given in table 1. The physicochemical characteristics of said layers are also given in detail in table 2.

[0088] Four tiles (examples 1 to 3 and reference) are thus produced from each of layers CU 1 to CU 3 and CU REF. These tiles are self-leveling, and are generally placed on the floor without glue, owing to a male-female assembly system in the form of dovetails.

TABLE-US-00001 TABLE 1 compositionof the tiles Type/% Example Example Example by weight 1 2 3 Reference Back layer (3) Flexible Flexible Flexible Flexible PVC PVC PVC PVC PVC 41% 41% 41% 41% Liquid DINP/16% DINP/16% DINP/16% DINP/16% plasticizer Fillers CaCO.sub.3/41% CaCO.sub.3/41% CaCO.sub.3/41% CaCO.sub.3/41% Additives 2% 2% 2% 2% Surface layer Rigid Rigid Rigid Flexible (4) PVC PVC PVC PVC (CU1) (CU2) (CU3) (CU REF) PVC/K-wert 85.4%/K60 85.4%/K50 85.4%/K60 72%/K64 Liquid DINCH + DINCH + DINCH + DINCH + plasticizers ESO/7.2% ESO/7.2% ESO/7.2% ESO/26.7% Additives** 1.4% 1.4% 1.4% 1.3% Impact Clearstrength Clearstrength Elvaloy None absorbers W300/5.9% W300/5.9% 741/5.9%

[0089] The additives in particular comprise lubricants, process aids, thermal stabilizers and any pigments.

TABLE-US-00002 TABLE 2 Characteristic properties of the obtained tiles Example 1 Example 2 Example 3 Reference Layer in question Backing CU 1 rigid CU 2 rigid CU 3 rigid CU REF sublayer (flexible) (3a and 3c) Thickness 4 mm 2 mm 2 mm 2 mm 2 mm Appearance Pigmented Transparent Transparent Transparent Transparent Shore D hardness (51 ± 1) (70 ± 4) (66 ± 1) (71 ± 1) (46 ± 1) Tg (tan δ) in ° C. .sup.(1) 39.74 77.8 74.1 67.8 47.2 Elasticity modulus 119 2429 1778 1894 60 (MPa) .sup.(2) Maximum force 9 46 36 32 21 (MPa) .sup.(2) Elongation at break 70 64 64 155 210 (%) .sup.(2) Static indentation Not 0.02 0.03 0.05 0.13 (standard EN 433)* applicable Average dimensional Not 0.09 0.15 0.09 0.06 stability (Standard applicable EN 434)* Scraping resistance (according to CSTB Not +++ (>37 N/ ++ (>34 N/ ++ (>31 N/ (<19N/ notebook no. 3562): applicable mm.sup.2) mm.sup.2) mm.sup.2) mm.sup.2) critical stress .sup.(1) Tg determined by rheology on a flat/flat rheometer of the Thermofisher Haake Mars type, equipped with a 25 mm wheel: ramp at 5.2° C./min from 180° C. to 25° C. .sup.(2) Mechanical traction properties determined according to standard ISO 527 on a traction bench of the Shimadzu autograph AGS-X type traction bench , on dumbbell-shaped samples of 58 mm (length between the jaws) × 5 mm (straight width outside attachments zone) × 2 mm thick, at a speed of 10 mm/min.

[0090] Regarding the scraping resistance test, the stresses indicated in table 2 correspond to the stresses applied for which the wear layer, and in particular the printed decorative film, were not perforated.

[0091] The results demonstrate a very strong improvement of the scraping resistance for the tiles according to the disclosure, examples 1 to 3 all obtaining a resistance greater than 35 N/mm.sup.2. This stress value makes it possible to obtain a tile with level r1, or even r2. The static indentation of the tiles according to the disclosure is also greatly reduced owing to the use of a wear layer comprising a layer of rigid PVC according to the disclosure.

Examples 4 and 5

[0092] Planks according to FIG. 6, corresponding to the construction of LVT (“Luxury Vinyl Tiles”) planks, were manufactured according to table 3, by static pressing (3 minutes of heating at 165° C. and 10 bars followed by 4 minutes of cooling under 10 bars). [0093] The planks comprise a back layer (3): [0094] made entirely from plasticized flexible PVC for the reference plank (REF 2); [0095] made from a stack of a balancing layer made from filled rigid PVC (3e) bonded between two inner layers of flexible PVC (3a, 3c); [0096] a wear layer (2) comprising a printed decorative PVC film (2a) on which a 0.5 mm transparent surface layer (4) is laminated, made from flexible PVC (reference example 4), or rigid PVC (example 5). The wear layers of example 4 and reference example 2 copy the composition of the reference wear layer CU REF of the preceding table 2.

[0097] The layers made from flexible PVC (3a, 3c) comprise the following ingredients, expressed in percentages by weight: 29% PVC, 9% plasticizers (DINP), 8% additives (process aids, thermal stabilizers, pigments) and 54% calcium carbonate (CaCO.sub.3).

[0098] The rigid PVC balancing layer (3e) comprises the following ingredients, expressed in percentages by weight: 50% PVC, 4.5% plasticizers, 0.5% additives (process aids, thermal stabilizers, pigments), 3.5% impact absorbers and 41.5% calcium carbonate (CaCO.sub.3).

[0099] The physicochemical characteristics of the layers (3e) and (3a, 3c) thus obtained are summarized in table 4.

[0100] The transparent surface layer (4) is in turn obtained by calendaring a dry blend of a formula with a flexible PVC or rigid PVC base.

[0101] The obtained planks are self-weighting, and are therefore generally placed on the floor without glue, owing to a male-female assembly system in the form of clicks, like that described in patent application WO 2016/030627 by the applicant.

TABLE-US-00003 TABLE 3 composition of the LVT planks Type/% by weight Example 4 Example 5 Reference 2 Back layer (3) Flexible layer 3a, bonded to the balancing layer Flexible PVC 3e bonded to the flexible layer 3c Flexible layer Balancing layer Flexible layer (3a) (3e) (3c) PVC 29% 50% 29% 29% Plasticizer DINP; 9% DINCH + ESO DINP; 9% DINP/9% 4.2% Fillers CaCO.sub.3; 54% CaCO.sub.3; 41.5% CaCO.sub.3; 54% CaCO.sub.3/54% Additives  0.5% 0.8% 0.5% 8% Impact absorbers n/a Clearstrength n/a n/a W300: 3.5% Thickness 1.35 mm 3 mm 1.35 mm 5.7 mm Surface layer (4) Flexible PVC Rigid PVC Flexible PVC (CU REF) (CU5) (CU REF) PVC/K-value 72%/K64 84%/K50 72%/K64 Total plasticizer DINCH + ESO/26.7% ESO/4.2% DINCH + ESO/26.7% Other additives 1.3% 1.3% 1.3% Impact absorbers None Clearstrength None W300/11.7% n/a: Not applicable

[0102] The additives in particular comprise lubricants, process aids, thermal stabilizers and any pigments.

[0103] The properties of the various layers making up the obtained planks are summarized in table 4.

TABLE-US-00004 TABLE 4 Characteristic properties of the manufactured LVT layers Layer in question flexible layer balancing layer rigid (CU5) (3a or 3c) (3e) Shore D hardness (66 ± 1) (79 ± 1) (78 ± 1) Tg (tan δ ) in ° C. .sup.(1) 54.05 74.2 74.8 Elasticity modulus 337 2001 2408 (MPa) .sup.(2) Maximum force 6 18 51 (MPa) .sup.(2) Elongation at break 30 4 12.4 (%) .sup.(2) .sup.(1) Tg determined by rheology on a flat/flat rheometer of the Thermofisher Haake Mars type, equipped with a 25 mm wheel: ramp at 5.2° C./min from 180° C. to 25° C. .sup.(2) Mechanical traction properties determined according to standard ISO 527 on a traction bench of the Shimadzu Autograph AGS-X type, on dumbbell-shaped samples of 58 mm (length between the jaws) × 5 mm (straight width outside attachments zone) × 2 mm thick, at a speed of 10 mm/min.

[0104] The properties of LVT planks manufactured according to the architecture described in table 3 are indicated in table 5:

TABLE-US-00005 TABLE 5 Characteristic properties of manufactured LVT planks Example 4 Example 5 Reference 2 Static indentation 0.05 0.03 0.29 (standard EN 433) Average dimensional 0.12 0.08 0.11 stability (Standard EN 434) Scratch resistance* −/+ +++ −/+ *Scratch resistance evaluated qualitatively after 10 cycles at 25 rpm, on a linear Taber equipped with a 1 mm tungsten carbide tip.

[0105] The results demonstrate that the static indentation of the tiles according to the disclosure is reduced owing to the use of a balancing layer (3e). The use of a wear layer comprising a layer of rigid PVC according to the disclosure in example 5 also makes it possible to improve the scratch resistance greatly.