Floor panel and method of manufacturing a floor panel

Abstract

Provided is a panel for constructing a floor or wall covering. The panel includes a core which includes a mineral material and at least one dendritic additive for improving the flexibility and tensile strength of the panel. The panel further includes at least one pair of opposite side edges. The pair of opposite side edges are provided with interconnecting coupling means for interconnecting adjacent panels.

Claims

1. A panel for constructing a floor or wall covering comprising: a core comprising a mineral material and comprising at least one pair of opposite side edges wherein the opposite side edges are provided with interconnecting coupling means for interconnecting adjacent panels, wherein the core further comprises at least one dendritic additive within the core wherein the mineral material comprises magnesium oxide, magnesium oxysulfate or magnesium oxychloride or wherein the mineral material comprises magnesium oxide, magnesium oxysulfate and magnesium oxychloride.

2. The panel according to claim 1, comprising at least one top layer affixed to said core.

3. The panel according to claim 2, wherein the dendritic additive is a dendritic polymer.

4. The panel according to claim 3, wherein the dendritic polymer is non-linear.

5. The panel according to claim 4, wherein the core comprises 0.1 to 10 wt % dendritic additive.

6. The panel according to claim 5, wherein the core is a multilayer core.

7. The panel according to claim 6, wherein the core comprises at least one upper core layer and at least one lower core layer, wherein at least one core layer comprises at least one dendritic additive.

8. The panel according to claim 7, wherein the core comprises at least one reinforcing layer.

9. The panel according to claim 8, wherein the reinforcing layer comprises fiber glass, polypropylene, jute, cotton and/or polyethylene terephthalate or wherein the reinforcing layer comprises fiber glass, polypropylene, jute, cotton and polyethylene terephthalate.

10. The panel according to claim 9, wherein the dendritic additive is a nanodendritic additive.

11. The panel according to claim 10, wherein at least part of the dendritic additive has an average particle size in the range of 5 to 250 micrometers.

12. A method of manufacturing a panel for constructing a floor or wall covering according to claim 1, comprising adding at least one dendritic additive to the core.

13. The method according to claim 12, wherein at least one pair of opposite side edges of the panel is provided with interconnecting coupling means for interconnecting adjacent panels and wherein at least part of the dendritic additive has an average particle size in the range of 5 to 250 micrometers.

14. The panel according to claim 1, wherein at least part of the dendritic additive has an average particle size in the range of 50 to 100 micrometers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of an exemplary panel.

(2) FIG. 2 is a side view of an exemplary panel.

DETAILED DESCRIPTION

(3) The panel according to the present invention may comprise at least one top layer affixed to said core. The top layer may for example be a decorative layer. It is also conceivable that the top layer comprises a decorative layer and a wear layer covering said decorative layer. The decorative layer may be composed of a film provided and/or printed with a motif. The decorative layer may be a paper layer and/or a polymer layer, such as a PVC layer. The wear layer is commonly substantially transparent. The wear layer may consist of one or more transparent lacquer layers. Typically, the thickness of the layer(s) in the panel is in the range of 0.2 to 2.0 mm. The panel according to the present invention is typically a laminated panel. A decorative top layer, if applied, may for example comprise at least one ply of cellulose-based layer and a cured resin, wherein the cellulose-based layer is preferably paper or kraft paper. Said ply of cellulose-based material may also be a veneer layer adhered to a top surface of the core layer. The veneer layer is preferably selected from the group consisting of wood veneer, cork veneer, bamboo veneer, and the like. Other decorative top layers that could possibly be applied for the present invention include a ceramic tile, a porcelain tile, a real stone veneer, a rubber veneer, a decorative plastic or vinyl, linoleum, and decorative thermoplastic film or foil. The top layer may possibly be further provided with a wear layer and optionally a coating. Examples of thermoplastics which could be used in such top layer are PP, PET, PVC and the like. It is also possible to provide on the top facing surface of the core an optional primer and print the desired visual effect in a direct printing process. The decorative top layer can receive a further finishing with a thermosetting varnish or lacquer such as polyurethane, PUR, or a melamine based resin.

(4) It is also conceivable that the panel comprises at least one backing layer affixed to the core. It is also conceivable that the panel comprises (at its back surface) at least one balancing layer, generally composed of at least one layer comprising lignocellulose and a cured resin. The panel may also comprise at least one acoustic layer, usually composed of a low density foamed layer of ethylene-vinyl acetate (EVA), irradiation-crosslinked polyethylene (IXPE), expanded polypropylene (XPP), expanded polystyrene (XPS), but also nonwoven fibers such as made from natural fibers like hemp or cork, or recycled/recyclable material such as PET or rubber. The density of this acoustic layer preferably has a density between 65 kg/m3 and 300 kg/m3, most preferably between 80 kg/m3 and 150 kgm3.

(5) The dendritic additive can for example be a dendritic polymer. Such dendritic polymer can possibly have a monodisperse framework or a polydisperse framework. Non-limiting examples of possible dendritic polymers are dendrimers, dendrons, star polymer, hyperbranched polymer, dendrigrafts or linear-dendritic polymers. The dendritic polymer is preferably non-linear. The dendritic additive can for example be a dendritic polyurethane. Further non-limiting examples of dendritic polymers are polylactic acid, polypropylene and/or polysiloxane. Per definition, one-dimensional and/or polymers with a straight chain do not fall within the scope of a dendritic additive according to the present invention.

(6) Preferably, the core comprises in the range of 0.1 to 10 wt % dendritic additive, preferably in the range of 0.5 to 5 wt %, and more preferably in the range of 1 to 2 wt %. It is for example possible that the amount of dendritic additive is in the range of 0.7 to 2 wt % of the total weight of mineral material. It is experimentally shown that said ranges provide the most promising results with respect to the desired material properties for the goal of the invention.

(7) It is conceivable that the core is a multilayer core. Hence, the core may comprise at least one upper core layer and at least one lower core layer, wherein at least one core layer comprises at least one dendritic additive. Preferably all core layers comprise at least one dendritic additive. It is possible that different core layers have a different density. It is conceivable that the core comprises at least one reinforcing layer. In a possible embodiment, the core comprises multiple core layers wherein two adjacent core layers enclose a reinforcing layer. The presence of at least one reinforcing layer may further enhance the impact resistance of the core, and thus the panel. At least one reinforcing layer may for example be present in the form of a reinforcing mat, a membrane and/or a mesh. At least one reinforcing layer may for example comprise fiber glass, polypropylene, jute, cotton and/or polyethylene terephthalate.

(8) At least part of the dendritic additive may possible be a nanodendritic additive. The use of nanodendritic additive may positively affect the crystallization of the mineral material within the core. It is also conceivable that at least part of the dendritic additive has an average particle size in the range of 5 to 250 micrometer, preferably in the range of 50 to 100 micrometer. The surface area of the dendritic additive is for example in the range of 5 m.sup.2/g to 50 m.sup.2/g.

(9) FIG. 1 shows a perspective view of a possible embodiment of a flooring panel (101) according to the present invention. The panel (101) includes a core (102) including a mineral material. The core (102) includes two pairs of opposite side edges (107a, 107b, 107c, 107d) and a top side (103). A first pair of opposite side edges (107c, 107d) is provided with interconnecting coupling means (108a, 108b) for interconnecting adjacent panels (101). The interconnecting coupling parts (108a, 108b) are shown as an illustration, any type of conventional coupling parts could be applied. The core layer (102) includes at least one dendritic additive.

(10) FIG. 2 shows a cross section of a further embodiment of a flooring panel (201) according to the present invention. The panel (201) includes a core (202) which includes a mineral material and at least one dendritic additive. The panel (201) includes interconnecting coupling means (208a, 208b) for interconnecting adjacent panels (201). The panel (201) further includes a top layer (204) affixed to the core (201). The core (202) is a multilayer core which includes an upper core layer (202a) and a lower core layer (202b). The two adjacent core layers (202a, 202b) enclose a reinforcing layer (205).

(11) The invention also relates to the use of a panel and to the use of a panel comprising dendritic particles in core of a mineral based floor panel.

(12) The invention further relates to a method of manufacturing a panel suitable for constructing a floor or wall covering, in particular a panel according to the present invention, wherein the core is made by adding least one dendritic additive to a mineral material.

(13) The mineral material comprising the core may for example be a magnesium oxide or magnesia (MgO). The magnesia can be calcined in order to affect the reactivity of the material. With respect to the present invention, the magnesia is typically obtained via a calcination process which is applied at temperatures of about 600 to 1300 degrees Celsius, preferably between 800 and 1000 degrees Celsius, such that reactive magnesia, which has a relatively high reactivity, is obtained. Reactive magnesia is also known in the field as “caustic-calcined magnesia” or light-burned magnesia. Typically, this is a highly reactive calcined MgO with a relatively small crystallite size. The magnesium cement, which can be used as primary core material, can be produced by mixing this reactive magnesia with an aqueous magnesium salt solution (usually including MgSO4, MgCl2 and/or MgCO3), then mixing this slurry with additives and water. Subsequently, the slurry is cured in order to form a ceramic material. This ceramic cement is poured onto a mold, and allowed to set, typically at either ambient or elevated temperature until it has cured. Non-limiting examples of these cements which can be used are magnesium chloride (MOC), magnesium oxysulfate (MOS) or magnesium carbonate. The magnesium chloride cement can be present in the 5-1-8 phase (5Mg(OH)2.MgCl2.8H2O) or the 3-1-8 phase (3Mg(OH)2.MgCl2.8H2O). Both of these phases form needle- or whisker-like crystals which benefit from useable properties, such as a dense microstructure and high bending strength. Magnesium oxysulfate cement can be present in the 5-1-3 phase (5Mg(OH)2.MgSO4.3H2O) or the 3-1-8 phase (3Mg(OH)2.MgSO4.8H2O). The former shows a needle- or whisker-like structure of typically 0.2 to 1.0 micrometer in diameter and a length of 20 to 50 micrometer; whereas the latter shows a flaky crystal structure.

(14) At least one dendritic additive is preferably added to the abovementioned slurry during mixing prior to curing. The dendritic additive can achieve that a three-dimensionally expanded flexible crystallization matrix will be formed that serves as a frame for the crystallization of the magnesia. This three-dimensionally expandable dendritic additive typically consists of a material that features a resemblance to or have dendrites, including linear or non-linear branched polymers, star polymers, dendrimers that can provide an interwoven skeleton to the setting magnesia cement crystals. When the term dendrimer is used, repetitively branched molecules can be meant. Typically not included are any linear, one-dimensional and/or straight-chained polymers such as polyethylene, nylon, polyester, PVC, PAN, alkanes or similar.

(15) It is also conceivable that instead of a magnesium based core any other crystal based cement is used in relation to the present invention.

(16) The method may further comprise a step wherein least one pair of opposite side edges of the panel is provided with interconnecting coupling means for interconnecting adjacent panels. This can be any conventional coupling means, such as aforementioned non-limiting examples.

(17) The invention also relates to a method of manufacturing a panel suitable for constructing a floor or wall covering, according to the present invention, wherein at least one dendritic additive is added to the core.