Panel for forming a floor covering and method for manufacturing such panels

1. A method for manufacturing panels, said panel having a substrate at least comprising a first substrate layer and a second substrate layer enclosing a glass fiber layer, wherein said method comprises at least the steps of:

forming a first substrate layer of a first thermoplastic material and a second substrate layer of a second thermoplastic material, wherein for forming said first substrate layer, a first granulate comprising said first thermoplastic material is strewn on an underlying surface, after which a glass fiber layer in the form of a non-woven glass fiber fleece or a woven glass fiber cloth from a roll is placed on this strewn layer, and thereafter, for forming said second substrate layer, also a second granulate comprising said second thermoplastic material is strewn on said glass fiber layer, wherein in a subsequent step both substrate layers, including the glass fiber layer, are consolidated between belts of a continuous pressing device, and wherein the first thermoplastic material is polyvinyl chloride having a plasticizer content of more than 12 percent by weight, and said second thermoplastic material is polyvinyl chloride having a plasticizer content of less than 5 percent by weight, and

providing a printed decor and a translucent or transparent wear layer on said two substrate layers, wherein these steps are performed after having consolidated said first substrate layer and the second substrate layer, including the glass fiber layer, wherein said translucent or transparent wear layer is provided above the printed decor, is based on thermoplastic material, and has a thickness of less than 1 millimeter,

wherein said panel is a floor panel and has a thickness between 2.5 and 6 millimeters.

2. The method of claim 1 , wherein said first granulate and/or second granulate also comprises individual glass fibers.

3. The method of claim 1 , wherein at least for the step of providing said wear-layer, it is started from a thermoplastic film, which is connected to the consolidated assembly of said two layers by means of thermal lamination.

4. The method of claim 1 , wherein said granulate of the first layer and/or the second layer shows an average particle size of 2 millimeters or less.

5. The method of claim 1 , wherein said first granulate and/or said second granulate comprises at least 50 percent by weight of fillers.

6. The method of claim 1 , wherein the composition and/or the average particle size of the first granulate is different in comparison with the second granulate.

7. The method of claim 6 , wherein the first granulate further differs from the second granulate in one or in a combination of two or more of the following features:

the granulates have a different average particle size, wherein one of the granulates has an average particle size of 1.5 to 2.5 millimeters and the other of the granulates has an average particle size of less than 1 millimeter;

the granulates have a different composition in that one of the granulates is obtained from fresh polyvinyl chloride and the other is obtained from a recyclate of polyvinyl chloride;

the granulates have a different composition in that one of the granulates comprises 60 to 80 percent by weight of filler, such as chalk, and the other comprises less than 50 percent by weight of filler, or no filler.

8. The panel obtained according to a method with the characteristics of claim 1 , wherein this panel comprises at least two layers of thermoplastic material and wherein said two layers substantially consist of a strewn and pressed granulate, wherein the respective layers enclose a glass fiber layer and/or wherein said two layers are formed of granulate having a mutually differing composition and/or mutually differing average particle size.

9. The method of claim 1 , wherein said printed decor is provided on a synthetic material film.

10. The method of claim 1 , wherein said method further comprises the step of milling profiled edges to said first and second substrate layer, wherein said profiled edges comprise mechanical coupling means substantially shaped as a tongue and a groove, wherein said groove is limited by an upper lip and a lower lip.

11. The method of claim 1 , wherein said method further comprises the step of levelling the surface of at least one of said two substrate layers prior to the step of providing said printed decor.

12. The method of claim 1 , wherein said translucent or transparent wear layer has a thickness between 0.15 and 1.0 millimeter millimeters.

13. A method for manufacturing panels, said panel having a substrate at least comprising a first substrate layer and a second substrate layer enclosing a glass fiber layer, wherein said method comprises at least the steps of:

forming a first substrate layer of a first thermoplastic material and a second substrate layer of a second thermoplastic material, wherein for forming said first substrate layer, a first granulate comprising said first thermoplastic material is strewn on an underlying surface, after which a glass fiber layer in the form of a non-woven glass fiber fleece or a woven glass fiber cloth from a roll is placed on this strewn layer, and thereafter, for forming said second substrate layer, also a second granulate comprising said thermoplastic material is strewn on said glass fiber layer, wherein in a subsequent step both substrate layers, including the glass fiber layer, are consolidated between belts of a continuous pressing device, and wherein the first thermoplastic material is polyvinyl chloride having a plasticizer content of more than 12 percent by weight, and said second thermoplastic material is polyvinyl chloride having a plasticizer content of less than 5 percent by weight, and

providing a printed decor and a translucent or transparent wear layer on said two substrate layers, wherein these steps are performed after having consolidated said first substrate layer and the second substrate layer, including the glass fiber layer, wherein said translucent or transparent wear layer is provided above the printed decor, is based on thermoplastic material, and has a thickness of less than 1 millimeter, and

wherein at least one of the first substrate layer, the second substrate layer, or the glass fiber layer is at least situated in a middle of the thickness of the substrate, and

wherein said panel is a floor panel and has a thickness between 2.5 and 6 millimeters.

14. The panel according to claim 13 , wherein the glass fiber layer is a glass fiber fleece.

15. The method of claim 13 , wherein said printed decor is provided on a synthetic material film.

16. The method of claim 15 , wherein said synthetic material film is a film on the basis of polyvinylchloride with a plasticizer content of less than 5 percent by weight.

17. The method of claim 15 , wherein said synthetic material film is a film chosen from the list consisting of Polyvinyl chloride film, Polyurethane film, Polypropylene film, Polyethylene terephthalate film.

18. The method of claim 13 , wherein said method further comprises the step of milling profiled edges to said first and second substrate layer, wherein said profiled edges comprise mechanical coupling means substantially shaped as a tongue and a groove, wherein said groove is limited by an upper lip and a lower lip.

19. The method of claim 13 , wherein said method further comprises the step of levelling the surface of at least one of said two substrate layers prior to the step of providing said printed decor.

20. The method of claim 13 , wherein said translucent or transparent wear layer has a thickness between 0.15 and 1.0 millimeter millimeters.

21. A method for manufacturing panels, said panel having a substrate at least comprising a first substrate layer and a second substrate layer enclosing a glass fiber layer, wherein said method comprises at least the steps of:

forming a first substrate layer of a first thermoplastic material and a second substrate layer of a second thermoplastic material, wherein for forming said first substrate layer, a first granulate comprising said first thermoplastic material is strewn on an underlying surface, after which a glass fiber layer in the form of a non-woven glass fiber fleece or a woven glass fiber cloth from a roll is placed on this strewn layer, and thereafter, for forming said second substrate layer, also a second granulate comprising said second thermoplastic material is strewn on said glass fiber layer, wherein in a subsequent step both substrate layers, including the glass fiber layer, are consolidated between belts of a continuous pressing device, and wherein the first thermoplastic material is polyvinyl chloride having a plasticizer content of more than 12 percent by weight, and said second thermoplastic material is polyvinyl chloride having a plasticizer content of less than 5 percent by weight, and

providing a printed decor and a translucent or transparent wear layer on said two substrate layers, wherein these steps are performed after having consolidated said first substrate layer and the second substrate layer, including the glass fiber layer, wherein said translucent or transparent wear layer is provided above the printed decor, is based on thermoplastic material, and has a thickness of less than 1 millimeter,

wherein at least one of the first substrate layer, the second substrate layer, or the glass fiber layer is located halfway in the thickness of said substrate, wherein the first substrate layer, the second substrate layer, and the glass fiber layer form the entire substrate of said floor panel, and

wherein said panel is a floor panel and has a thickness between 2.5 and 6 millimeters.

22. The method of claim 21 , wherein said translucent or transparent wear layer has a thickness between 0.15 and 1.0 millimeter millimeters.