Floor panel and method for manufacturing a floor panel

Abstract

A floor panel with a substrate and a decoration provided thereon. The substrate includes at least a foamed layer of thermoplastic material and at least a reinforcement layer. Additionally, a method for manufacturing such floor panels with a substrate and a decoration, where the substrate includes at least a foamed layer of thermoplastic material and at least a reinforcement layer.

Claims

1. A floor panel having a substrate and a decoration, wherein the substrate comprises at least a foamed layer and a non-foamed layer, wherein said foamed and non-foamed layer comprise thermoplastic material, wherein the floor panel, on at least two opposite edges, is provided with coupling means allowing to couple two of such floor panels to each other, wherein at the respective edges a locking is effected at least in a vertical direction perpendicular to a plane of the panels, wherein at least one of said edges is provided with a groove, wherein said groove is bordered by an upper lip and a lower lip, wherein said groove has a most proximal point, said most proximal point being situated in said foamed layer and the lower surface of said upper lip at least partially being formed in said non-foamed layer, and wherein the lower surface of the upper lip is also at least partially formed in said foamed layer.

2. The floor panel according to claim 1, wherein said foamed layer is a foamed PVC layer.

3. The floor panel according to claim 1, wherein said non-foamed layer is adjacent to one of the surfaces of said foamed layer.

4. The floor panel according to claim 1, wherein said non-foamed layer comprises the same thermoplastic material as said foamed layer.

5. The floor panel according to claim 1, wherein said non-foamed layer is situated between the decoration and said foamed layer.

6. The floor panel according to claim 1, wherein said decoration comprises a printed motif.

7. The floor panel according to claim 6, wherein said printed motif is provided on a thermoplastic foil.

8. The floor panel according to claim 7, wherein the floor panel also comprises a translucent or transparent wear layer, which is provided above said decoration.

9. The floor panel according to claim 1, wherein at the respective edges a locking is effected in a horizontal direction in the plane of the panels and perpendicular to the edges, wherein at least one of said edges is provided with an upward-directed hook-shaped looking part, wherein said upward-directed hook-shaped locking part extends at least partially in a portion of the substrate which is free from said foamed layer.

10. The floor panel according to claim 1, wherein the upper surface of the lower lip is at least partially formed in said foamed layer.

11. The floor panel according to claim 10, wherein said upper surface of the lower lip also is at least partially formed in a portion of the substrate which is free from said foamed layer.

12. The floor panel according to claim 1, wherein at the respective edges a locking is effected at least in a vertical direction perpendicular to the plane of the panels, as well as in a horizontal direction in the plane of the floor panels and perpendicular to the respective edges, wherein said locking in vertical direction is provided by two pairs of cooperating contact surfaces, wherein a first pair is formed in said foamed layer, whereas a second pair is formed by a portion of the substrate which is free from said foamed layer.

13. The floor panel according to claim 12, wherein said second pair of cooperating contact surfaces is formed on the lower side of the upper lip and is partially formed on said foamed layer and partially on said non-foamed layer.

14. The floor panel according to claim 13, wherein said first pair of cooperating contact surfaces is formed on the upper surface of the lower lip, wherein said first pair of cooperating contact surfaces extends from in the actual groove to beyond the upper lip.

15. The floor panel according to claim 12, wherein said second pair of cooperating contact surfaces is inclined with an inclination larger than 15°.

16. The floor panel according to claim 1, wherein said groove is provided for cooperation with a tongue on the opposite edge.

17. The floor panel according to claim 16, wherein, in coupled condition of said tongue and groove, a space is present on the lower side of the tongue, wherein said space extends from a tip of the tongue up to a position underneath the upper lip.

18. The floor panel according to claim 1, wherein the floor panel, seen in thickness, comprises at least 2 millimeters of thermoplastic material which is free from plasticizer or has a plasticizer content of less than 12 phr.

19. The floor panel according to claim 18, wherein the floor panel, seen in thickness, comprises at least 4 millimeters of foamed thermoplastic material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) With the intention of better showing the characteristics of the invention, herein below, as an example without any limitative character, some preferred embodiments are described, with reference to the accompanying drawings, wherein:

(2) FIG. 1 represents a floor panel having the characteristics of the invention;

(3) FIG. 2, at a larger scale, represents a cross-section according to the line 11-11 indicated in FIG. 1;

(4) FIG. 3, at the same scale, represents the coupled condition of two of such floor panels;

(5) FIGS. 4 to 10, in a similar view, represent variants;

(6) FIG. 11, at a larger scale, represents a cross-section according to the line XIXI indicated in FIG. 1;

(7) FIGS. 12 to 14, in a similar view, represent variants; and

(8) FIG. 15 schematically represents some steps in a method according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

(9) FIG. 1 represents a rectangular floor panel 1.

(10) FIG. 2 clearly shows that the floor panel 1 comprises a substrate 2 and a decoration 3 provided thereon.

(11) The substrate 2 comprises a foamed layer 4 of thermoplastic material, in this case polyvinyl chloride (PVC). This foamed layer 4 is positioned such that it is at least centrally present in the substrate 2, namely on the central line C. In this case, the thickness T1 of the foamed layer forms more than 40 percent of the thickness T2 of the substrate. For the rest, the substrate 2 in this case only comprises not yet foamed layers 5-6-7.

(12) The substrate 2 of the floor panel 1 from the example of FIGS. 1 and 2 comprises a first and a second reinforcement layer 8-9, in this case glass fiber layers, more particularly glass fiber mats (nonwoven). A first reinforcement layer 8 is situated on the surface 10, which is directed towards the decoration 3, of the foamed layer 4 and, together with the second reinforcement layer 9, it encloses the foamed layer 4. Said second reinforcement layer 9 herein is situated on the opposite surf ace 11 of the foamed layer 4.

(13) Said decoration 3 comprises a printed motif and represents a single wooden plank. The printed motif is provided on a thermoplastic foil 12, namely a PVC foil. Further, the floor panel 1 comprises a transparent or translucent wear layer 13, which is provided above said decoration 3.

(14) In the example, said non-foamed layers 5-6-7 comprise a first non-foamed layer 5 and a second non-foamed layer 6, which respectively are adjacent to said surfaces 10-11 of the foamed layer 4, and, in this case, also to the reinforcement layers 8-9 present there. These first and second non-foamed layers 5-6 consist of the same thermoplastic material, namely PVC, as the foamed layer 4, however, preferably contain a higher content of fillers, such as chalk or talc. The floor panel of FIG. 2 forms an example of a substrate 2 where the respective non-foamed layers 5-6 enclose the foamed layer 4.

(15) The substrate 2 of FIG. 2 further also comprises a third non-foamed layer 7 of thermoplastic material. This third non-foamed layer 7 is situated between the decoration 3 and said first non-foamed layer 5 and contains a content of plasticizer which is higher than the plasticizer content possibly present in the foamed layer 4 and/or is higher than the plasticizer content possibly present in the first and/or second non-foamed layer 5-6.

(16) Preferably, the non-foamed layer 6 on the lower surface 11 of the foamed layer 4, namely the second non-foamed layer 6, is made thicker than said first foamed layer 5 on the upper surface 10 of the foamed layer 4, for example, with a thickness T6 which is larger than 1.5 times the thickness TS of the first non-foamed layer 5. Preferably, the sum of the thickness TS of the first non-foamed layer 5 and the thickness T7 of the third non-foamed layer 7 is approximately equal to, equal to or larger than the thickness T6 of the second non-foamed layer 6, preferably at least 10 percent larger, however, less than 50 percent larger. In this manner, the second foamed layer 6 can counteract possibly remaining tensions in the first and third foamed layers 5-7 in an optimum manner.

(17) The substrate 2 of the floor panel 1 of FIG. 4 forms an example of the most preferred embodiment mentioned in the introduction, wherein the substrate 2 comprises a foamed layer 4 of thermoplastic material, preferably of PVC with a plasticizer content lower than 12 phr or without plasticizer, and wherein the substrate 2 further also shows one or more non-foamed layers 5-6-7 on both surfaces 10-11 of the foamed layer 4, which non-foamed layers respectively also being preferably of PVC with a plasticizer content of less than 12 phr. The ratio of the overall thickness of all non-foamed layers 6 on the one surface 11 to the thickness of the non-foamed layers 5-7 on the other surface 10 of the foamed layer 4 is between 0.75 and 1.33, namely, in this case approximately 0.8. The whole of non-foamed layers 6 in this case is thinner on the lower surface 11 than the whole of non-foamed layers 5-7 on the upper surface 10 of the foamed layer 4; however, within said ratio. The average plasticizer content of the non-foamed layers 5-7 on the upper surface 10 is higher than the average plasticizer content of the non-foamed layers 6 on the lower surface 11, as the aforementioned third non-foamed layer 7 contains a higher plasticizer content than the possible plasticizer content in the first and second non-foamed layer 5-6. In the example, said reinforcement layers 8, 9 respectively form the separation between the foamed layer 4 and said whole of non-foamed layers.

(18) The floor panel 1 from the example is, at least on the two opposite long edges 14-15, provided with coupling means 16 allowing to couple two of such floor panels 1 to each other, wherein, as represented in FIG. 3, a locking is effected at the respective edges 14-15 in a vertical direction V perpendicular to the plane of the panels 1, as well as in a horizontal direction H perpendicular to the respective edges and in the plane of the panels 1. To this aim, the panel 1, on at least one of its long edges 15, is provided with a groove 17, wherein the deepest point 18 of this groove 17 is situated in said foamed layer 4. In this case, the groove 17 is provided for cooperation with a tongue 19 on the opposite edge 14 and is bordered by an upper lip 20 and a lower lip 21, wherein the lower lip 21, in distal direction, extends to beyond the upper lip 20, or, in other words, beyond the groove opening 22. FIG. 2 represents that the tongue 19 can be inserted into the groove 18 by means of a turning movement W around the respective edges 14-15.

(19) In this case, the upper surface 23 of the lower lip 21 is entirely formed of the material of said foamed layer 4, and the lower lip 21, in the proximity of its distal end 24, is provided with a hook-shaped locking part 25, which in this case also consists of material of the foamed layer 4. The hook-shaped part 25 is intended for, in coupled condition, cooperating with a locking groove 26 on the lower side of the edge 14 which is provided with said tongue 19, and effects said locking in horizontal direction H. To this aim, a pair of horizontally active contact surfaces 27-28 is formed between said hook-shaped part 25 and the locking groove 26. The contact surfaces 27-28 are formed on the material of the foamed layer 4.

(20) In the example, the lower surface 29 of the upper lip 20 is practically completely formed in a portion of the substrate 2 which is free from said foamed layer 4. In coupled condition, a first pair of vertically active contact surfaces 30-31 is formed on this portion which is free from the material of the foamed layer 4. A second pair of vertically active contact surfaces 32-33 is formed on the upper surface 23 of the lower lip 21 and on the material of the foamed layer 4. In this case, the second pair of vertically active contact surfaces 32-33 is at least partially situated underneath the upper lip 20, namely, in the actual groove 17, thus, proximally in respect to the groove opening 22.

(21) One of the reinforcement layers 9 extends uninterruptedly in said lower lip 21, whereas the second of said reinforcement layers 8 extends in the material of said tongue 19. In this manner, material portions which protrude from the edges 14-15 will be additionally supported. Herein, also the presence of a portion of a non-foamed layer 5-6-7 in the tongue 19 as well as in the lower lip 21 is advantageous. The stability of the upper lip 20 is guaranteed by the non-foamed layers 5-7 present there.

(22) The foamed layer 4, as well as the first and second non-foamed layers 5-6, are free from plasticizer or contain a plasticizer content of less than 12 phr. The third non-foamed layer 7, too, contains a plasticizer content of less than 12 phr. Thus, the substrate 2 consists entirely of layers 4-5-6-7 having a plasticizer content of less than 12 phr, if plasticizer were present at all in the respective layers 4-5-6.

(23) The layers of the substrate 2 represented here are attached to each other by means of a thermal laminating process. The foamed layer 4 and the first and second non-foamed layers 5-6 are obtained by means of strewing and consolidating thermoplastic material, whether or not in the form of granulate or so-called dry-blend.

(24) FIG. 4 represents an example of a floor panel 1 according to the invention, which shows the same layer composition as the floor panel 1 of the FIGS. 1 to 3, with the exception of an additional foam layer 34 on the lower side of the substrate. Here, this relates to a foam layer 34 of cross-linked or interconnected polyethylene (XPE), which by means of glue is attached to the remaining substrate portions, in particular to the non-foamed layer 6. In this case, this relates to a soft foam.

(25) FIG. 4 further clearly shows that in this case the lower surface 29 of the upper lip 20 is formed entirely from the foamed layer 4, including the pair of vertically active contact surfaces 30-31 present there. In coupled condition, in this example, a space 35 is present on the lower side of the tongue 19, which space extends at least from the tip of the tongue 19 to beyond the upper lip 20. The reinforcement layers 8, 9 are situated in the upper lip 20 as well as in the lower lip 21 and extend uninterruptedly in these.

(26) In the case of FIG. 3 as well as FIG. 4, the locking groove 26 extends up into the upper half of the substrate, namely up to above the level C. Preferably, the substrate 2 comprises at least one reinforcement layer 8, which, as is the case here, extends uninterruptedly above said locking groove 26, whereas the possible other one of the reinforcement layers 9, at least at the location of said locking groove 26, is omitted or is removed.

(27) FIG. 5 represents an example with similar substrate portions as FIG. 4. However, the edge profile is different. The upper surface 23 of the lower lip 21 is formed partially in the material of the foamed layer 4, as well as in the material of the underlying non-foamed layer 6. Herein, the reinforcement layer 9 on the lower surface 11 of the foamed layer 4 is interrupted at the location of the deepest zone 36 in said upper surface 23.

(28) Preferably, as represented here, at the location of this deepest zone 36 at least half of the thickness of the whole of non-foamed layers 6 remains conserved at the lower surface 11. The horizontally active contact surfaces 27-28 for the major part are formed on the material of the foamed layer 4, however, for a part are also formed on the material of the underlying non-foamed layer 6. The reinforcement layer 9 is interrupted in said lower lip 21, however, intersects the aforementioned horizontally active contact surfaces 27-28.

(29) In the example of FIG. 5, the lower surface 29 of the upper lip 20 is formed practically entirely in the foamed portion 4 of the substrate 2. In coupled condition, a first pair of vertically active contact surfaces 30-31 is formed on this portion. A second pair of vertically active contact surfaces 32-33 is formed on the upper surface 23 of the lower lip 20, also on the material of the foamed layer 4. In this case, the second pair of vertically active contact surfaces 32-33 is situated at least partially, and here even entirely, underneath the upper lip 21, namely, in the actual groove 17, or, in other words, proximally in respect to the groove opening 22.

(30) FIG. 6 for the substrate 2 shows a similar layer construction as the FIGS. 4 and 5.

(31) Above the decoration 3 in this case a wear layer 13 is applied, which also comprises a superficial lacquer layer 37. Possibly remaining tensions in the respective lacquer layer 37 hardly have any effect on the upper lip 21, as this shows portions of non-foamed layers 5-7, which are free from plasticizers or have a plasticizer content of less than 12 phr or still better of less than 7 phr. Moreover, a reinforcement layers 8 extends uninterruptedly in this upper lip 20.

(32) It is evident that a superficial lacquer layer 37 may form part of the wear layer 13 of any embodiment of floor panels 1 according to the present invention.

(33) In the case of FIG. 6, the edge profile comprises coupling means 16 with, at the tongue side 14, a convex lower side, and a cooperating therewith concave upper surface 23 of the lower lip 20 at the groove side 15. At the location of the horizontally active contact surfaces 27-28, an overlap 38 is provided in the contour of the coupling means 16, such that in the coupled condition a tension is created at least on these horizontally active contact surfaces 27-28. With the vertically active contact surfaces 30-31 on the upper side of the tongue 19 and the lower side of the upper lip 20, a tension may be created as well, either by a local overlap in the contour at that position, or that said overlap 38 at the location of the horizontally active contact surfaces 27-28 creates a tension which has an effect on the vertically active contact surfaces 30-31. This latter preferably is achieved by somewhat inclining the vertically active contact surfaces 30-31, as it is the case here. Preferably, these vertically active contact surfaces 30-31, in such case and globally seen, enclose an angle A in the range of 2° to 15°.

(34) It is clear that such inclination of the first pair of vertically active contact surfaces 30-31 can be applied in any floor panel 1 with the characteristics of the invention, independently from the fact whether or not an overlap 38 is applied in the contour of the coupling means 16. FIGS. 1 to 9 moreover all form examples of the application of a slighter inclination, namely of less than 10°. In the example of FIG. 10, a stronger inclination than 10° is applied, however, still less than 45° namely in the example approximately 30°.

(35) Further, it is clear that an overlap 38 at the location of the horizontally active contact surfaces 27-28 can also be applied in any floor panel 1 with the characteristics of the invention.

(36) FIG. 7 represents an example wherein the substrate 2 is constructed similarly as in FIG. 6, however, with the exception of the additional foamed layer 34 on the lower side of the substrate 2. While in FIG. 6 the vertically active contact surfaces 30-31 and the horizontally active contact surfaces 27-28 are formed on the material of the foamed layer 4, in the case of FIG. 7 the vertically active contact surfaces 30-31 are formed on a non-foamed layer 5 present on the upper surface 10 of the foamed layer 4. While in FIG. 6 the reinforcement layer 9 in the lower lip 21 is interrupted, it extends uninterruptedly in the lower lip 21 of the embodiment of FIG. 7. The overlap 38 of the contours, realized on the hook-shaped part 25 in FIG. 7, is more limited than in the case of FIG. 6.

(37) FIG. 8 represents an example with approximately the same substrate portions as the example of FIG. 2, however, wherein the third foamed layer 7 mentioned there is omitted. The edge profiles show the same shape as those of FIG. 4, however, here they are realized such that the upper surface of the upper lip 20 for the major part is formed in the non-foamed layer 6 present on the lower surface 11 of the foam layer 4.

(38) The horizontally active contact surfaces 27-28 on the hook-shaped part 25 are formed in the material of said foam layer 4, as well as in the material of the underlying non-foamed layer 6. The reinforcement layer 9 is interrupted in said lower lip 21, however, intersects said horizontally active contact surfaces 27-28, in this case, approximately in the middle. Preferably, as represented here, at the location of the deepest zone 36 in the upper surface of the lower lip 21, at least half of the thickness of the whole of non-foamed layers 6 is maintained on the lower surface 11 of the foamed layer 4.

(39) FIG. 9 shows an example wherein the substrate 2 comprises a foamed layer 4 with a reinforcement layer 8 situated on the upper surface 10 of the foamed layer 4, and wherein the substrate 2 further also comprises a not yet foamed layer 7 A on said upper surface 10. In this case, the applied non-foamed layer 7 A shows the composition of the third non-foamed layer 7 mentioned within the scope of the preceding examples, namely a plasticizer content of more than the possible plasticizer content in the foamed layer 4.

(40) In this case, the foamed layer 4 is obtained by means of consolidating and foaming strewn powders of thermoplastic material, whereas the non-foamed layer 7 A is obtained by liquid application or calendering of thermoplastic material onto the already formed foamed layer 4. The substrate 2 comprises only one reinforcement layer 8, namely on the upper surface 10 of said foamed layer 4.

(41) For the major part thereof, the edge profiles represented in the example of FIG. 9 are formed in the foamed layer 4. In this example, in coupled condition a space 35 is present on the lower side of the tongue 19, which space extends at least from the tip of the tongue 19 to beyond the upper lip 20. The reinforcement layer 8 is situated in the upper lip 20. On the upper surface 23 of the lower lip 20, however, more distally than the upper lip 21, namely beyond the groove opening, vertically active contact surfaces 32-33 are situated. In this case, even the upper surface of the hook-shaped part 25 forms a vertically active contact surface 39. This latter is not necessarily so.

(42) FIG. 10 represents another embodiment wherein a similar construction of the substrate 2 is applied as in FIG. 9, however, wherein the, in this case single, reinforcement layer 8 is embedded in the foamed layer 4, in this case centrally or approximately central, in the foamed layer 4.

(43) In the edge profiles of FIG. 10, a pair of vertically active contact surfaces 30-31 on the lower side 29 of the upper lip 20 partially is formed on said foamed layer 4 and partially on said non-foamed layer 6. In coupled condition, in this example, a space 35A is present on the lower side of the tongue 19, which space extends from the tip of the tongue 19 up to a position underneath the upper lip 21. On the upper surface 23 of the lower lip 21, a pair of vertically active contact surfaces 32-33 is formed, which extends from in the actual groove 17 to beyond the upper lip 20. Between this pair of vertically active contact surfaces 32-33 and the horizontally active contact surfaces 27-28 formed on the hook-shaped part 25, a space 40 is provided.

(44) FIG. 10 further also shows that deep embossments 41 can be formed on the surface of the floor panel 1. In this case, this relates at least to embossments 41 with a depth D of approximately 0.4 mm for forming a chamfer. FIG. 10 clearly shows that the non-foamed layer 7 A receives a portion of the embossment 41, as in this case a non-foamed layer 7 A has been chosen for, with a higher plasticizer content than the foamed layer 4.

(45) The decoration 3 which is present follows the embossment 41.

(46) In connection with the contour overlaps 38 represented in FIGS. 6 and 7, it is noted again that similar contour overlaps of course are possible in all embodiments. In the coupled condition of two of such floor panels, such contour overlaps 38 may lead to the presence of a bent-out lower lip 21, as mentioned in the introduction, or to a material compression at least at the location of the horizontally active contact surfaces 27-28.

(47) In all examples, the depth G of the groove 17 is less than the thickness T1 of the foamed layer 4. Such profile is preferred in view of stability of the coupling and, in particular, of the upper lip 20, however, it is not indispensable. This is of particular importance when use is made of a superficial lacquer layer 37 as a part of the wear layer 13.

(48) As already mentioned, in all examples the vertically active contact surfaces 30-31 on the upper side of the tongue 19 and the lower surface 29 of the upper lip are made inclined. In the case of FIGS. 1 to 9, rather limited, namely with an angle between 2° and 15°, or even between 2 and 70 in the cases of the FIGS. 1 to 8. In the case of FIG. 10, an inclination is applied which is larger than 15°, namely in this case approximately 30°.

(49) In all examples, the lower lip 21 of the groove 17 protrudes to beyond the upper lip 20 over a distance E which is at least two times the thickness T1 of the foamed layer A. Although the lower lip 21 does not necessarily has to protrude, and also coupling means 16 can be applied with a shorter or equally long lower lip, such as, for example, the coupling means of WO 97/47834 or WO 01/98603, a protruding lower lip 21 is preferred. The extent of protrusion of the lower lip, or the distance E, preferably is at least one time the thickness T1 of the foamed layer 4. The extent of protrusion preferably is less than one and a half time the overall thickness T of the floor panel 1, and preferably is more than half of the thickness T of the floor panel 1, as it here is the case in all examples. Although in the figures each time a chamfer is represented in the form of an inclination at the upper edge of the floor panels 1, this is not indispensable within the scope of the invention. The respective upper edges can also be realized without a chamfer or with another type of chamfer. According to a particular embodiment, use can be made of a chamfer performed through said decoration 3 up into the underlying substrate portion. The respective substrate portion as such then possibly can be provided with a matching or possibly contrasting uniform coloration, or the surface of the inclination can be provided with a separate decorative covering, for example, a lacquer layer or a print. For examples of such chamfers reference is made to WO 2012/004701.

(50) FIG. 11 represents the short edges 42-43 of the floor panel 1 of FIGS. 1 to 3. Herein, an edge profile with a male part 44 and a female part 45 is applied, which allows coupling two of such floor panels 1 at the respective edges 42-43 by means of a downward movement M of the male part 44 in the female part 45, wherein in coupled condition a locking is effected in a horizontal direction H as well as in a vertical direction V. The combination of a turnable profile at the long edges 14-15, for example, according to any of the FIGS. 2 to 10, and a downward coupleable profile at the short edges 44-45, for example, according to any of the FIGS. 11 to 14, leads to the creation of a floor panel 1 which can be coupled by means of a so-called fold-down movement. Herein, the long edges 14-15 are provided in each other by a turning movement W, wherein by this turning movement W at the short edges 42-43 a downward movement M is created, which provides the male part 44 present there in the female part 45.

(51) The example of such downward coupleable profile represented here is made in one piece with the material of the floor panel 1 and comprises, in order to effect the locking, a cooperating snap hook 46 and undercut 47, as well as a hook-shaped part 25 on the lower lip 21, which in this case also comprises an undercut 47A. The undercut 47A at the hook-shaped part 25 is made such that it forms an angle A 1 with the vertical of 1° to 10°, and preferably approximately 5°. The locking groove 26 which cooperates with the aforementioned hook-shaped part 25 is entirely positioned underneath the reinforcement layer 8 at the upper surface 10 of the foamed layer 4.

(52) The aforementioned cooperating snap hook 46 and undercut 47 in this case in the coupled condition comprise cooperating vertically active contact surfaces 30-31, which are partially realized in the foamed layer 4 and partially in the non-foamed layer 5 situated there above. The horizontally as well as vertically active contact surfaces 27 A-28A of the hook-shaped part 25 are realized entirely in the material of the foamed layer 4.

(53) The upper surface 23 of the lower lip 21 consists entirely of material of the foamed layer 4. In coupled condition, the edge profiles also have vertically active contact surfaces 32-33 formed on this upper surface 23. Between these vertically active contact surfaces 32-33 and horizontally active contact surfaces 27 A-28A, a space 40 is present. The lower reinforcement layer 9 extends in one piece in the lower lip 21, and the upper reinforcement layer 8 extends in one piece over the aforementioned locking groove 26. At the lower side of the lower lip 21, a recess 48 is realized which extends at least partially underneath said space 40. This latter provides for a smoother coupling, even with the represented overlap 38 in the contours.

(54) FIG. 12 represents a variant of profiles which can be coupled into each other with a downward movement M wherein the snap hook 46 is situated at the distal end 24 of the lower lip 21 of the female part 45, whereas the undercut 47 is provided in the male part 44. Here, too, the upper surface 23 of the lower lip 21 is formed entirely from the material of the foamed layer 4, and in coupled condition the edge profiles comprise vertically active contact surfaces 32-33 formed on this upper surface 23. Between these vertically active contact surfaces 32-33 and horizontally active contact surfaces 27 A-28A, a space 40 is present. The lower reinforcement layer 9 extends in one piece in the lower lip 21, and the upper reinforcement layer 8 extends in one piece over said locking groove 26.

(55) In the example of FIG. 12, too, the hook-shaped part 25 is realized with an undercut 47 A, wherein this undercut 47A is realized such that it forms an angle A 1 with the vertical of 1° to 10°, and preferably approximately 5°. It is evident that in FIG. 11 as well as in FIG. 12 such undercut 47A at the location of the horizontally active contact surfaces 27A-28A on the hook-shaped part 25 is not necessary and that just as well contact surfaces 27-28 can be used which are vertical or which are inclined less steeply than the vertical, for example, with an inclination comparable to that of the horizontally active contact surfaces 27-28 of FIGS. 1 to 10, namely an inclination wherein the respective contact surfaces 27-28 enclose an angle with the horizontal of 45° to 90°.

(56) FIG. 13 represents a variant of downwardly coupleable profiles, wherein the snap hook 46 is formed by a separate insert 49, which, in this case, is provided in the male part 44. Such separate insert 49 preferably is also formed of thermoplastic material, for example, at least of PVC or ABS (Acrylonitrile butadiene styrene), and in coupled condition preferably, such as here, comprises a vertically active contact surface 50 with the material of a non-foamed layer 7 of the female part 45. In this manner, an exact vertical positioning of the male part 44 in the female part 45 can be achieved. In this example, said separate insert 49 is situated in a seat with upper walls 51 which are formed of non-foamed material, and lower walls 52 which are formed of foamed material.

(57) FIG. 14 represents still another example of profiles which can be coupled into each other in downward direction, wherein in this example the undercut 47 is formed by a separate insert 49, which to this aim, in this case, is provided in the female part 45. Such separate insert 49 preferably is also formed of thermoplastic material, for example, at least of PVC or ABS (Acrylonitrile butadiene styrene) and, in coupled condition, such as here, preferably comprises a vertically active contact surface 50 with the material of a foamed layer of the male part 44. Said separate insert 49 is situated in a seat with upper walls 51 which are formed of non-foamed material, and lower walls 52 which are formed of foamed material.

(58) Relating to FIGS. 13 and 14, it is also noted that it is advantageous to also have non-foamed material above the seat of the separate insert 49, preferably with a plasticizer content of less than 12 phr, and still better of less than 7 phr. Namely, in this manner, it is achieved that the risk of deformation of the upper surface of the floor panels 1 due to force effects during coupling or in the coupled condition is minimized.

(59) It is clear that the hook-shaped part 25, the cooperating therewith locking groove 26 at the male part 44, respectively, in the examples of FIGS. 11 to 14 respectively extends up into the upper half of the substrate, thus, to above the level C.

(60) It is clear that the edge profiles of FIGS. 11 to 14 can be realized in various alternative manners, wherein the contact surfaces present can be realized on different substrate portions, similar to the in the introduction herein above-mentioned possibilities for tongues and/or grooves, however, wherein the tongue 19 is replaced by a whether or not one-piece snap hook 46, and the groove 17 is formed by an undercut 47, whether or not provided by a separate insert 49.

(61) Further, it is clear that the edge profiles from FIGS. 2 through 10 can also be applied on the short edges 42-43, wherein then the same or not the same profile is applied at the long edges 14-15 as well as at the short edges 42-43.

(62) It is also noted that edge profiles, such as those of FIGS. 11 to 14, of course also can be applied in other substrates 2 with the characteristics of the invention, such as, for example, in the substrates 2 of FIGS. 4 to 6 and 8 to 10.

(63) FIG. 15 schematically represents some steps in a possible method for manufacturing floor panels 1.

(64) The method comprises the step S1 of providing a thermoplastic material 53. In this case, this step S1 is performed three times by means of three separate strewing treatments 54A-548-54C. The method further also comprises the step S2 of providing a prefabricated sheet, in this case two glass fiber mats 8-9, which respectively are situated between two of the aforementioned three strewn materials.

(65) In a first strewing treatment 54A, the material is strewn for a first layer which is not to be foamed. In a second strewing treatment 548, the material is strewn for a first layer which is to be foamed. In a third strewing treatment 54C, the material is strewn for a second layer which is not to be foamed. It is clear that the composition provided by means of the second strewing treatment 54B is at least different from that of the first and third strewing treatments 54A-54C. Said glass fleeces 8-9 form an effective separation between these materials. Moreover, they carry the strewn material, together with the underlying transport belt 55, through the continuous production process. It is clear that the strewing treatments 54A-54B-54C described herein above can be applied for obtaining a substrate portion with a central foamed layer 4, which, on both surfaces 10-11, is provided with a glass fiber mat 8-9 and an adjacent thereto non-foamed layer 5-6, similar to the foamed layer 4, reinforcement layers 8-9 and a first and second non-foamed layer 5-6 from the examples of FIGS. 2 to 8 and 11 to 14.

(66) In a subsequent step S3, at least the material of the second strewing treatment 54B is foamed in the presence of the aforementioned glass fiber mats 8-9. This is performed between the belts of a double-belt press 56. The double-belt press 56 is heated in a first part 57 and cooled in a second part 58. The obtained foam can have an impact on the heat transfer in the press, considering that it can function as an insulator. In order to avoid an overly large impact on the line speed, the strewn material preferably is preheated before being treated in the press.

(67) Following the press treatment, in a step 4 a further substrate layer 60 can be deposited on the surface of the obtained substrate portion 59, in liquid condition, for example by means of a so-called calendering treatment 61. Referring to FIGS. 2 to 7, it is also noted that this further substrate layer 60, for example, may relate to the mentioned there third, non-foamed layer 7.

(68) It is noted that, in a step not further represented here, the method can be continued by applying a decoration 3, possibly in the form of a printed foil 12, and a wear layer 13, which possibly can comprise a lacquer layer 37.

(69) As described in the introduction, it is possible to connect one or more of the prefabricated sheets, namely, the glass fiber mats 8-9, to the thermoplastic material 53 under tension, for example, by pulling at it in longitudinal direction.