Floor panels

1. A floor panel comprising at least a substrate and a top layer, said top layer comprising a decorating layer comprising a decorative printed pattern,

wherein the substrate comprises at least one first layer of a first thermoplastic material and a second layer of a second thermoplastic material, wherein the second layer is adjacent to a first side of the first layer,

wherein said first and second layers comprise polyvinyl chloride (PVC), carbon black pigment and at least 30 weight parts of fillers per 100 weight parts of polyvinyl chloride, wherein said fillers are selected from a list consisting of calcium carbonate and talc, wherein at least one of said first and second layers comprises plasticizers in an amount of less than 12 parts of plasticizers per hundred parts of polymer or is free from plasticizers,

wherein the floor panel is provided, on at least two opposite edges, with coupling means that allow two such floor panels to be coupled together,

wherein said first and second layers have a different colour.

2. The floor panel according to claim 1 , wherein the first layer is defined by a first colour with luminance value L1 in a Hue-Saturation-Luminance (HSL) colour space and the second layer is defined by a second colour with luminance value L2 in the HSL colour space, wherein L1 is different from L2.

3. The floor panel according to claim 2 , wherein the absolute value of L1-L2 is less than or equal to 50.

4. The floor panel according to claim 2 , wherein L2<L1.

5. The floor panel according to claim 2 , wherein a larger of L1 and L2 is less than or equal to 85.

6. The floor panel according to claim 2 , wherein the first colour has a saturation value S1 in the HSL colour space and the second layer has a saturation value S2 in the HSL colour space, and where S1 and S2 are each less than or equal to 25.

7. The floor panel according to claim 2 , wherein a hue of the first colour is defined by an angle H1 in the HSL colour space and a hue of the second colour is defined by an angle H2 in the HSL colour space and where the smaller angle between H1 and H2 is less than or equal to 175°.

8. The floor panel according to claim 1 , wherein in a coupled condition of said two opposite edges, locking is brought about at least in a horizontal direction in a surface of the floor panels and perpendicular to the edges, wherein at least one of the edges is provided with a hook-shaped locking part directed upwards, wherein the hook-shaped locking part is formed at least from the material of said first layer.

9. The floor panel according to claim 1 , wherein in a coupled condition of said two opposite edges, locking is brought about at least in a horizontal direction in a surface of the floor panels and perpendicular to the edges, wherein at least one of the edges is provided with a hook-shaped locking part directed upwards, wherein the hook-shaped locking part is formed at least from the material of said second layer.

10. The floor panel according to claim 1 , wherein in a coupled condition of said two opposite edges, locking is brought about at least in a vertical direction perpendicular to a surface of the floor panels, wherein at least one of the edges is provided with a groove, wherein this groove is flanked by an upper lip and a lower lip and wherein an upper surface of the lower lip is formed at least from the material of said first layer.

11. The floor panel according to claim 1 , wherein in a coupled condition of said two opposite edges, locking is brought about at least in a vertical direction perpendicular to a surface of the floor panels, wherein at least one of the edges is provided with a groove, wherein this groove is flanked by an upper lip and a lower lip and wherein a lower surface of the upper lip is formed at least from the material of said first layer.

12. The floor panel according to claim 1 , wherein in a coupled condition of said two opposite edges, locking is brought about at least in a vertical direction perpendicular to a surface of the floor panels, wherein at least one of the edges is provided with a groove, wherein this groove is flanked by an upper lip and a lower lip and wherein the lower surface of the upper lip is formed at least from the material of said second layer.

13. The floor panel according to claim 1 , wherein in a coupled condition of said two opposite edges, locking is brought about at least in a vertical direction perpendicular to a surface of the floor panels, as well as in a horizontal direction in the surface of the floor panels and perpendicular to the edges, wherein the locking in the vertical direction is provided by at least one pair of interacting contact surfaces partly formed in the first layer, whereas said locking in the horizontal direction is provided by at least one pair of interacting contact surfaces formed at least from the material of said second layer.

14. The floor panel according to claim 1 , wherein the second layer is positioned under the first layer in the floor panel.

15. The floor panel according to claim 1 , wherein each of the one or more further layers of thermoplastic material is defined individually by a luminance value Lx.

16. The floor panel according to claim 15 , wherein for each of the one or more further layers the colour has a luminance value Lx that is different from L1.

17. The floor panel according to claim 15 , wherein for at least one of the one or more further layers the colour has a luminance value Lx that is identical to L2.

18. The floor panel according to claim 15 , wherein each of the one or more further layers of thermoplastic material is defined individually by a saturation value Sx, wherein each Sx is less than or equal to 25.

19. The floor panel according to claim 15 , wherein each of the one or more further layers of thermoplastic material is defined individually by a hue with angle Hx, wherein a smaller angle between H1 and each of the Hx is less than 175°.

20. The floor panel according to claim 15 , wherein a largest of L1, L2 and all Lx is less than or equal to 85.

21. A floor panel comprising at least a substrate and a top layer, said top layer comprising a decorating layer, said decorating layer being a thermoplastic film provided with a decorative printed pattern,

wherein the substrate comprises at least one first layer of a first thermoplastic material and a second layer of a second thermoplastic material, wherein the second layer is adjacent to a first side of the first layer,

wherein said first and second layers comprise polyvinyl chloride (PVC), carbon black pigment and at least 30 weight parts of fillers per 100 weight parts of polyvinyl chloride, wherein said fillers are selected from a list consisting of calcium carbonate and talc, wherein at least one of said first and second layers comprises plasticizers in an amount of less than 12 parts of plasticizers per hundred parts of polymer or is free from plasticizers,

wherein the floor panel is provided, on at least two opposite edges, with coupling means that allow two such floor panels to be coupled together, and wherein said coupling means are formed at least from the material of both said first and second layers, wherein in a coupled condition of said two opposite edges, locking is brought about at least in a vertical direction perpendicular to a surface of the floor panels, wherein at least one of the edges is provided with a groove, wherein this groove is flanked by an upper lip and a lower lip and wherein an upper surface of the lower lip is formed at least from the material of said first layer,

wherein the first layer is defined by a first colour with luminance value L1 in a Hue-Saturation-Luminance (HSL) colour space and the second layer is defined by a second colour with luminance value L2 in the HSL colour space, wherein L1 is different from L2.

22. The floor panel according to claim 21 , wherein a hue of the first colour is defined by an angle H1 in the HSL colour space and a hue of the second colour is defined by an angle H2 in the HSL colour space and where the smaller angle between H1 and H2 is less than or equal to 175°.

23. The floor panel according to claim 21 , wherein the absolute value of L1-L2 is less than or equal to 50.