PANEL AND METHOD FOR MANUFACTURING A PANEL

Abstract

A panel having a substrate and a top layer provided thereon, wherein the top layer comprises at least a melamine resin and a binder, the binder being selected from the group comprising: polyacrylates based binder, polyvinyl acetate based binder, polyester based binder, acrylic copolymers based binder or urethane based binder.

Claims

1.-52. (canceled)

53. A method for manufacturing a panel comprising the following steps: the step of providing a substrate; the step of providing a top layer comprising a binder and a melamine-based resin on top of the substrate; and the step of curing the melamine-based resin directly on top of the substrate.

54. The method of claim 53, wherein the binder is selected from a group consisting of: polyacrylates based binder, polyvinyl acetate-based binder, polyester based, acrylic copolymers based binder or urethane based binder.

55. The method according to claim 54, wherein the binder is urethane based.

56. The method according to claim 55, wherein the urethane-based binder comprises a urethane based acrylic copolymers dispersion in water.

57. The method according to claim 53, wherein the top layer comprises a binding layer comprising the binder and at least a melamine-based layer, and wherein the binding layer is interposed between the substrate and a melamine-based layer.

58. The method according to claim 57, wherein the binding layer comprises a décor.

59. The method according to claim 57, wherein the binding layer comprises a printed carrier having a décor and being impregnated with the binder.

60. The method according claim 53, wherein the top layer comprises a layer having a mixture of the melamine-based resin and of the binder.

61. The method according to claim 53, wherein the top layer comprises a water absorbing substance.

62. The method according to claim 61, wherein the water absorbing substance is selected from a group consisting of: wood fibers, cellulose fibers, paper or mineral particles.

63. The method according to claim 53, wherein the substrate is substantially made of a synthetic material.

64. The method according to claim 53, wherein the method comprises a step of providing the binder on top of the substrate that comprises providing a carrier impregnated with the binder.

65. The method according to claim 53, wherein the curing step is a hot pressing step.

66. The method of claim 65, wherein the hot pressing step is performed at a temperature comprised between 140° C. and 220° C.

67. The method of claim 65, wherein the step of hot pressing is performed for a pressing comprised between 10 and 60 seconds.

68. A method for manufacturing a panel comprising the following steps: the step of providing a substrate; the step of providing a top layer on top of the substrate, wherein said top layer comprises a melamine-based resin, wherein the top layer comprises a decorative layer, and wherein the top layer further comprises a resin impregnated foil to be disposed between the decorative layer and the substrate; and the step of curing the melamine-based resin directly on top of the substrate.

69. The method of claim 68, wherein said resin impregnated foil is provided with a moisture content below 6%

70. The method of claim 68, wherein said decorative layer comprises a printed carrier.

71. A method for manufacturing a panel comprising the following steps: the step of providing a substrate; the step of providing a top layer on top of the substrate, wherein said top layer comprises a melamine-based resin, wherein the top layer comprises a decorative layer, and wherein the top layer further comprises a thermoplastic material layer to be disposed between the decorative layer and the substrate; and the step of curing the melamine-based resin directly on top of the substrate.

Description

[0084] FIG. 1 represents an upper view of a panel having the characteristics of the invention;

[0085] FIG. 2, at a larger scale, represents a cross-section according to the line II-II indicated in FIG. 1, according to a first embodiment;

[0086] FIG. 3 on a larger scale shows a view on the area F3 indicated on FIG. 2;

[0087] FIG. 4 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to a second embodiment of the invention;

[0088] FIG. 5 on a larger scale shows a view on the area F5 indicated on FIG. 4;

[0089] FIG. 6 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to a third embodiment of the invention;

[0090] FIG. 7 on a larger scale shows a view on the area F7 indicated on FIG. 6;

[0091] FIG. 8 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to a fourth embodiment of the invention;

[0092] FIG. 9 on a larger scale shows a view on the area F9 indicated on FIG. 8;

[0093] FIG. 10 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to a fifth embodiment of the invention;

[0094] FIG. 11 on a larger scale shows a view on the area F11 indicated on FIG. 10;

[0095] FIG. 12 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to a sixth embodiment of the invention;

[0096] FIG. 13 schematically represents some steps in a method according to the invention;

[0097] FIG. 14 schematically represents some steps in a method according to the invention;

[0098] FIG. 15 schematically represents some steps in a method according to the invention;

[0099] FIG. 16 schematically represents some steps in a method according to the invention;

[0100] FIG. 17 schematically represents some steps in a method according to the invention;

[0101] FIG. 18 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to a seventh embodiment of the invention;

[0102] FIG. 19 on a larger scale shows a view on the area F19 indicated on FIG. 18;

[0103] FIG. 20 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to an eight embodiment of the invention;

[0104] FIG. 21 on a larger scale shows a view on the area F20 indicated on FIG. 20;

[0105] FIG. 22 at a larger scale, represents a cross-section, according to the line II-II indicated in FIG. 1, according to another independent aspect of the invention;

[0106] FIG. 23 on a larger scale shows a view on the area F22 indicated on FIG. 22.

[0107] FIG. 1 represents a rectangular floor panel 1.

[0108] FIG. 2 clearly shows that the floor panel 1 comprises a substrate 2 and a top layer 3 provided thereon.

[0109] The substrate 2 is preferably waterproof and can comprise a synthetic material, for example vinyl based or phenolic based, a cement based material or a mineral based material. In the illustrated example, the substrate is vinyl based and comprises a PVC board, for example stiff foamed PVC. Examples of PVC boards are LVT, WPC or SPC boards.

[0110] In the illustrated example, the top layer 3 comprises a decorative layer 4 having a décor 5 that comprises a printed motif representing a single wooden plank (as visible from FIG. 1). In the preferred embodiment, as it will be explained further on, the decorative layer 3 comprises melamine-based resin.

[0111] In the illustrated examples, the top layer 3 further comprises an overlay 6 provided on top of the decorative layer 3 that is configured to protect the decorative layer 3 itself and that it is configured to act as a wear layer. It is noted that the overlay 6 is preferably transparent or translucent. In the preferred embodiment, as it will be explained further on, the overlay 6 comprises melamine-based resin.

[0112] As visible in FIG. 2 the layers comprising melamine resins, i.e. the decorative layer 3 and the overlay 6 shows a global thickness S, defined as the sum of the two thicknesses, below, 0.5 mm, preferably, below 0.25 mm, more preferable below 0.15 millimeter. Preferably, the thickness S of the layers comprising melamine resins is comprised between 0.11 and 0.13 millimeter.

[0113] The top layer 3 further comprises a binding layer 7 disposed between the decorative layer 3 and the substrate 2. The binding layer comprises a binder. The binder may be selected from the group comprising: polyacrylates based, polyvinyl acetate based, acrylic copolymer based, polyester based or urethane-based binder. For example, the binder is preferably a urethane-based binder, in particular, a urethane acrylic copolymer dispersion in water.

[0114] In the example shown in FIG. 2 the binding layer 7 shows a thickness T below 0.2 mm, preferably below 0.1 mm, for example approximately 0.05 mm.

[0115] The panel 1 from the example is, at least on the two opposite long edges 11, preferably on all the edges 11,12, provided with coupling means 13 allowing to couple two of such panels 1 to each other, wherein a locking is effected at the respective long and short edges 11,12 in a vertical direction perpendicular to the plane of the panels 1, as well as in a horizontal direction perpendicular to the respective edges and in the plane of the panels 1. In the example, the coupling means 135 are in the form of a tongue 14 and a groove 15.

[0116] FIG. 3 shows, on a larger scale, the detail F3 of FIG. 2. According to the embodiment shown in FIG. 3 the overlay 6 comprises a carrier, preferably a paper sheet 8, impregnated with the melamine-based resin M. Preferably the overlay 6 comprises wear resistant particles (not shown).

[0117] Similarly, according to the embodiment shown in FIG. 3 the decorative layer 4 comprises a printed paper sheet 9 provided with the décor 5 that is impregnated with the melamine-based resin M.

[0118] The binding layer 7, in the embodiment of FIG. 3, is disposed below the decorative layer 4 and the substrate 2, is free from any carrier in order to reduce the thickness T of the binding layer itself.

[0119] FIG. 3 also shows that the floor panel 1 comprises a relief structure 10 provided in the top layer 3, preferably in the overlay 6. According to the preferred embodiment, the relief structure 10 is in register with the décor 5.

[0120] FIGS. 4 and 5 show an alternative embodiment of the floor panel 1 that differs from the embodiment shown in FIGS. 2 and 3 wherein the binding layer 7 comprises a water absorbent substance 16. In this example, the water absorbing substance 16 is a paper sheet 17 impregnated with the binder B. According to alternative embodiments, the water absorbing substance 16 can comprise wood fibers, cellulose fibers, or mineral particles like silica particles.

[0121] FIGS. 6 and 7 shows one further embodiment that differs from the embodiment shown in FIGS. 2 and 3 in that the decorative layer 4 comprises a printed paper sheet 9 impregnated with the binder B. Therefore, the decorative layer 4 according to this embodiment is configured to act as the binding layer 8.

[0122] FIGS. 8 and 9 shows one further embodiment that differs from the embodiment shown in FIGS. 2 and 3 in that the décor 5 is printed directly onto the top surface of the substrate 2, for example by digital printing. The top layer 3 comprises transparent or translucent binding layer 8 comprising the binder B disposed above the décor 5 and below the overlay 6 comprising the melamine-based resin M impregnating a paper sheet 8. Alternatively, the overlay 6 could comprise a paper sheet 8 impregnated with a mixture comprising the binder B and the melamine-based resin M.

[0123] FIGS. 10 and 11 shows one further embodiment that differs from the embodiment shown in FIGS. 2 and 3 in that the top layer 3 comprises a decorative layer 4 having a printed paper sheet 9 impregnated with a mixture comprising the binder B and the melamine-based resin M.

[0124] FIG. 12 shows an alternative embodiment of the floor panel 1 of FIG. 2 wherein the substrate 2 is made of a phenolic based material. In particular, the substrate 2 comprises a plurality of phenolic impregnated sheets 18, for example paper sheets, pressed and cured onto each other.

[0125] FIGS. 18 and 19 shows one further embodiment that differs from the embodiment shown in FIGS. 2 and 3 in that the top layer 3 comprises a resin impregnated foil 19 disposed below the printed paper sheet 9 and above the binding layer 7. The resin impregnated foil 19 comprises a Kraft paper foil impregnated with melamine based, a phenol based, urethane based and/or acrylic-based resin R or a mixture thereof. The Kraft paper foil has a starting weight of between 50 and 200 g/sqm, more preferably between 100 and 180 g/sqm and is impregnated with a resin R content of between 30 and 100% wt of the start weight of the foil. The resin impregnated foil 19 comprises a weight, after impregnation, of between 250 and 300 g/sqm. For example, the moisture content of the resin impregnated foil 19 is below 6%, preferably below 4%, more preferably below 3%.

[0126] FIGS. 20 and 21 shows one further embodiment that differs from the embodiment shown in FIGS. 18 and 19 in that the top layer 3 comprises a thermoplastic material layer 20 disposed between the resin impregnated foil 19 and the substrate 2. In the example, the thermoplastic material layer 20 is disposed between the binding layer 7 and the resin impregnated foil 19. Anyway, in an alternative, not shown, embodiment, the thermoplastic material layer 20 can be disposed between the substrate 2 and the binding layer 7. The thermoplastic material layer 20 is a nonwoven sheet of thermoplastic fibers, preferably polyolefin, polypropylene, polyester and/or bicomponent polyester. The thermoplastic material layer 20 preferably comprises the water absorbing substance 16.

[0127] FIGS. 22 and 23 shows a one embodiment of the panel 1 according to the fourth independent aspect of the invention. In practice, the panel 1 of FIGS. 22 and 23 differs from the embodiment shown in FIGS. 20 and 21 in that the top layer 4 is free from any binder B or binding layer 7.

[0128] FIG. 13 schematically represents some steps in a possible method for manufacturing floor panels 1. In particular the method illustrated in FIG. 13 is directed to manufacture the panels according to the embodiment shown in FIGS. 2 and 3.

[0129] The method comprises the step S1 of providing the substrate 2 for forming the floor panel 1.

[0130] The method further comprises the step S2 of providing the binder B above the substrate 2. In the embodiment of FIG. 8 the step S2 of providing the binder B is performed by coating the top surface of the substrate 2 with the binder B, for example by means of a roll coater or sprayer. In this way the binding layer 7 is provided on top of the substrate 2.

[0131] Subsequently said step S2 of providing the binder B the method comprises the step S20 of drying the binder B itself in order to remove most of, preferably all of, the water contained in the binder B. This is particularly the case when the binder B comprises a binder that is in water dispersion. Said step S20 of drying the binder B may be performed via hot air blowing, IR radiation, NIR radiation or a combination of one or more of these techniques.

[0132] The method further continues with the step S3 of providing a décor 3 on top of the substrate 2. In this embodiment, the step of providing the décor 3 comprise laminating a printed paper sheet 9 impregnated with melamine resin m. Preferably, the melamine impregnated printed paper sheet 9 is provided in a B-stage condition wherein the portion of the hardened resin is above 80% wt of the total mass of the resin in the printed paper sheet 9.

[0133] The method further comprises the step S4 of providing a overlay 6, possibly in the form of a paper sheet 8 impregnated with melamine resin M. In this case, the melamine impregnated paper sheet 8 is preferably provided in a B-stage condition wherein the portion of the hardened resin is above 60% wt of the total mass of the resin in the paper sheet 8. This step S4 is performed by laminating the paper sheet 8 on the substrate 2. Alternatively, this step may be performed by coating the decoration 3 with the melamine resin M in liquid form for example by spraying or rolling, or, preferably, in dry form by spreading a dry melamine resin on the substrate 2.

[0134] The method continues with a curing step S5 of hot pressing the melamine resin M directly onto the substrate 2. Preferably, this step is performed at a pressure comprised between 20 and 80 kg/cm.sup.2, preferably between 35 and 60 kg/cm2.

[0135] In particular, according to a preferred embodiment of the invention the hot pressing step S5 is performed with a temperature above 175° C. and for a pressing time below 35 seconds. This S5 is performed with a temperature below 195° C. and for a pressing time above 12 seconds. This provides for a lower steam pressure between the melamine resin M and the substrate 2 to reduce the risk of delamination.

[0136] Preferably, during the curing step S5, the relief structure 10 can be embossed on the top layer of the panel.

[0137] The method further continues with the step S6 of providing the panel 1 with the coupling means 15, for example by milling the panel 1.

[0138] It is to be noted that according to an alternative but equivalent version of the embodiment shown in FIG. 13, the steps S2 and S20 may be performed on the bottom surface of the overlay 6 to be laminated on the substrate 2 during step S4 instead of the top surface of the substrate 2.

[0139] FIG. 14 shows an alternative embodiment of the method that is directed to manufacture the panels 1 of the embodiment shown in FIGS. 4 and 5. The method of FIG. 14 differs from the method of FIG. 13 in that the step S2 of providing the binder B is performed by placing, for example laminating, a sheet of water absorbing substance, for example a paper sheet, a wood fiber sheet, a cellulose fiber sheet, or minerals, previously impregnated with the binder B.

[0140] FIG. 15 shows an alternative embodiment of the method that is directed to manufacture the floor panels 1 of the embodiment shown in FIGS. 6 and 7. The method of FIG. 15 differs from those of FIGS. 13 and 14 by the fact that it comprises a step S21 of providing a printed paper sheet 9 impregnated with the binder B. This step S21 substantially substitutes and group together the steps S2 and S3 of the embodiments of FIGS. 13 and 14.

[0141] FIG. 16 shows an alternative embodiment of the method that is directed to manufacture the floor panels 1 of the embodiment shown in FIGS. 8 and 9. The method of FIG. 16 differs from those previously described in that it comprises a step S31 of printing the décor 5 directly on the top surface of the substrate 2. Preferably, this step is performed via digital inkjet printing. The method of FIG. 16 further continues with step S2 of providing the binder B above the décor 5. Moreover, in the embodiment of FIG. 16 the step S2 of providing the binder B is performed by coating the top surface of the substrate 2 with the binder B, for example by means of a roll coater or sprayer, and is followed by the drying step S20. Therefore, in the present embodiment, the steps S2 and S20 are similar to those of FIG. 9.

[0142] It is to be noted that according to an alternative but equivalent version of the embodiment shown in FIG. 11, the steps S2 and S20 may be performed on the bottom surface of the overlay 6 to be laminated on the substrate 2 during step S4 instead of the top surface of the substrate 2.

[0143] With regard to the embodiment shown in FIG. 16, it is not excluded that prior to said step 31 of providing the décor 5 the method comprises on or more steps of treating the top surface of the substrate 2 in order to prepare it for direct printing, for example a step of providing a primer on the top surface of the substrate 2.

[0144] FIG. 17 shows an embodiment of the method that is directed to manufacture the panels 1 of the embodiment shown in FIGS. 10 and 11. The method of FIG. 17 differs from the method of FIG. 13 in that it comprises the step S21 of providing a printed paper sheet 9 impregnated with a mixture of the melamine resin M and the binder B. This step S21 substantially substitutes and group together the steps S2 and S3 and S4 of the embodiments of FIGS. 13 and 14.

[0145] It is to be noted that the method in any of its embodiments may be directed to manufacturing a board having dimensions larger than those of the floor panel 1, and that after the step S5 of curing the melamine resin, the method comprises the step of cutting said board to obtain a plurality of panels 1. Said step of cutting may be performed before said step S6 providing the panel 1 with the coupling means 15.

[0146] The present invention is in no way limited to the herein above-described embodiments, on the contrary may such panels and methods be realized in various manners, without leaving the scope of the present invention.