METHOD FOR MANUFACTURING A PANEL INCLUDING A REINFORCEMENT SHEET

Abstract

A method for manufacturing a panel, the panel having a thickness in a range of 1.5 to 6.5 mm and including at least one substrate layer and a printed decoration layer covered by a protection layer. The method includes the steps of providing a granulate containing PVC and fillers, and having a cylindrical shape with a cylinder diameter in the range of 2.5 to 3.5 mm and a cylinder height in the range of 0.2-2.0 mm, melting the granulates and forming the substrate layer by means of molten granulates. The layer have a thickness of 1 to 3.5 mm. The method also includes forming a laminated complex by applying the printed decoration layer and the protection layer to at least the substrate layer by laminating or coating.

Claims

1-15. (canceled)

16. A method for manufacturing a panel, said panel having a thickness in a range of 1.5 to 6.5 mm and comprises at least one substrate layer, a printed decoration layer covered by a protection layer, wherein said method comprises the steps of: providing a granulate containing PVC and fillers, and having a cylindrical shape with a cylinder diameter in the range of 2.5 to 3.5 mm and a cylinder height in the range of 0.2-2.0 mm; melting said granulates and forming said substrate layer by means of molten granulates, said layer having a thickness of 1 to 3.5 mm; forming a laminated complex by applying said printed decoration layer and said protection layer to at least said substrate layer by laminating or coating.

17. The method of claim 16, wherein said granulate comprises at least 35% of inorganic fillers.

18. The method of claim 16, wherein granulate is provided by melting a mixture of PVC and fillers, extruding the mixture through a perforated plate, and cutting the extrudate every 0.2 to 2.0 mm.

19. The method of claim 16, wherein the panel further comprises a reinforcement sheet positioned on top of said substrate layer

20. The method of claim 16, wherein said substrate layer is provided in the form of said granulates which are spread and subsequently at least partially melted.

21. The method of claim 16, wherein said substrate layer is provided in molten condition on a conveyor belt.

22. The method of claim 16, wherein said PVC is semi-rigid PVC.

23. The method of claim 16, wherein said method is a continuous process in which at least said substrate layer is formed as a continuous sheet

24. The method of claim 16, said method further comprising the step of embossing said laminated complex.

25. The method of claim 16, said method further comprising the step of applying a UV lacquer on the top side of the laminated complex.

26. The method of claim 16, said method further comprising the step of cutting the laminated complex in slabs for further converting to finished modular floor elements.

Description

[0040] FIG. 1 is an illustrative side view of an apparatus for performing an embodiment of the method for manufacturing a panel according to the invention.

[0041] FIG. 1 shows a part of an apparatus 1 for continuously processing a web and illustrates some steps of an embodiment of a method for manufacturing a panel including a reinforcement sheet according to the invention. The apparatus 1 includes a granulate supply 2 which is adapted to supply a first layer or base layer 3 of granulate on a supporting lower conveyor belt 4. The lower conveyor belt 4 is an endless belt. The granulate is spread evenly on the lower conveyor belt 4. The granulate is made from a thermoplastic material, for example flexible PVC.

[0042] The lower conveyor belt 4 has a greater length than a second, upper endless conveyor belt 5 which is positioned at a distance downstream of the granulate supply 2 and runs along a part of the lower conveyor belt 4. At the upper portion of the lower conveyor belt 4, both conveyor belts 4, 5 run in the same manufacturing direction, in FIG. 1 from left to right as indicated by an arrow at the lower conveyor belt 4.

[0043] There is supplied a reinforcement sheet 6 on top of the base layer 3 of granulate. The reinforcement sheet 6 may be a glass fibre foil or any alternative foil which has reinforcement properties. The reinforcement sheet 6 is supplied by unwinding it from a supply roll 7. Subsequently, the reinforcement sheet 6 and the base layer 3 of granulate are transported between the lower and upper conveyor belts 4, 5 along a heating device 8 in order to melt the base layer 3 of granulates, and then pressed together by a pressing unit 9. The rate of melting may be such that the granulates are fully converted into a pasty substance, but it is also conceivable that the granulates are partially melted. The reinforcement sheet 6 and the base layer 3 are attached to each other under pressure through adhering properties of the melted thermoplastic material. Subsequently, the base layer 3 including the reinforcement sheet 6 are transported along a cooling unit 10. It is advantageous that the reinforcement sheet 6 is directly supported by a rigid press element of the pressing unit 9, since a soft layer between the reinforcement sheet 6 and the rigid press element would increase the risk of deformation or damage of the reinforcement sheet 6 by granulates of the first layer 3 that are not fully melted. It provides the opportunity to apply relative large granulates in the base layer 3.

[0044] In a next step a second layer or top layer 11 is provided on top of the reinforcement sheet 6. The top layer 11 is made from the same thermoplastic material as the base layer 3, but this may be different in an alternative embodiment. The thermoplastic material of the top layer 11 is melted and pressed into a sheet by nip rollers, and the still at least partially melted sheet 11 and the base layer 3 including the reinforcement sheet 6 are then pressed together by means of calandering rolls 12, resulting in a web having a smooth upper surface.

[0045] At a position downstream of the calandering rolls 12 there may be arranged a cutting mechanism (not shown) to cut the resulting continuous web into separate panels which are then collected for further processing.

[0046] In an alternative embodiment (not illustrated) the reinforcement sheet may be placed on top of a lower press plate or press member in a first step, after which thermoplastic granulates are spread over the reinforcement sheet to form the first layer. The granulates may be at least partially melted before or after spreading. Subsequently an upper press plate or press member is placed on top of the first layer and the lower and upper press plates or press members can press the first layer and the reinforcement sheet to each other. The resulting intermediate product may be turned upside down and the second layer of thermoplastic material, for example an at least partially melted sheet, can be applied on top of the reinforcement sheet at its side facing away from the first layer. In case of placing an at least partially melted sheet on top of the reinforcement sheet, this can be fixed thereto by means of calandering. It is also possible that the resulting intermediate product is not turned upside down and that that second layer is applied onto the reinforcement sheet when the reinforcement sheet extends below the first layer.

[0047] From the foregoing, it will be clear that the invention provides an improved method for manufacturing a panel including a reinforcement sheet.

[0048] The invention is not limited to the embodiment shown in the drawing and described hereinbefore, which may be varied in different manners within the scope of the claims and their technical equivalents. For example, the first layer may be applied on the lower conveyor belt in melted condition instead of first spreading and then melting the granulates. Furthermore, heating of the granulates of the first layer may be performed before laying the reinforcement sheet and the first layer onto each other.