Method for forming a décor on a substrate

Abstract

A method for forming a décor on a substrate, including providing a substrate having a surface, forming at least one portion in the surface of the substrate having an extension in a plane situated lower than or above a plane of the surface of the substrate, and digital printing a décor on the surface of the substrate and on said at least one portion by a common print bar, wherein the décor is continuously extending over the surface of the substrate and said at least one portion. Also, a building panel and a set of building panels.

Claims

1. A method for forming a décor on a substrate, comprising providing a substrate having a surface, forming at least one portion in the surface of the substrate, the at least one portion having an extension in a plane situated lower than or above a plane of the surface of the substrate, digital printing a décor on the surface of the substrate, and on said at least one portion, with a single-pass printer comprising at least one common print bar, wherein the common print bar is fixedly arranged at least 2 mm above the surface of the substrate, wherein the common print bar comprises print heads with a drop volume between 10-30 picoliters, and wherein the décor continuously extends over the surface of the substrate and said at least one portion.

2. The method according to claim 1, wherein the décor is present on said at least one portion.

3. The method according to claim 1, wherein said at least one portion in the surface of the substrate has an extension in a direction inclined in relation to the surface of the substrate.

4. The method according to claim 1, wherein said at least one portion forms a bevel along an edge of the substrate.

5. The method according to claim 4, wherein the bevel has a convex shape.

6. The method according to claim 1, wherein said at least one portion forms an embossed portion in the surface of the substrate.

7. The method according to claim 1, wherein said at least one portion forms a grout line in the surface of the substrate.

8. The method according to claim 1, wherein said at least one portion forms a protruding portion in the surface of the substrate.

9. The method according to claim 1, wherein said substrate comprises a core and a surface layer arranged on the core, said surface layer forming said surface of the substrate, and wherein said at least one portion is formed in the surface layer.

10. The method according to claim 9, wherein said at least one portion is formed in the surface layer only.

11. The method according to claim 1, wherein a position of the print bar in a vertical direction is fixed during printing.

12. The method according to claim 1, wherein a drop velocity of print heads of the print bar exceeds 8 m/s.

13. The method according to claim 1, wherein the print bar comprises one or several Piezo print heads.

14. The method according to claim 1, wherein said surface comprises a wood veneer, solid wood, a wood-based material, a thermoplastic foil, a co-extruded thermoplastic layer, paper, or non-woven.

15. The method according to claim 1, further comprising forming a mechanical locking system at at least one edge of the substrate prior to printing.

16. The method according to claim 15, further comprising digital printing on at least one surface of the mechanical locking system.

17. The method according to claim 15, wherein the mechanical locking system comprises a tongue at at least one edge of the substrate, and wherein the step of digital printing comprises printing said décor on the tongue with the common print bar, wherein the décor is continuously extending over the surface of the substrate, said at least one portion and the tongue.

18. A method for forming a décor on a substrate, comprising providing a substrate having a surface, forming at least one portion in the surface of the substrate, the at least one portion having an extension in a plane situated lower than or above a plane of the surface of the substrate, digital printing a décor on the surface of the substrate, and on said at least one portion by at least one common print bar, wherein the décor continuously extends over the surface of the substrate and said at least one portion, wherein the step of forming at least one portion comprises forming a first portion in the surface of the substrate having an extension in a plane situated lower than or above a plane of the surface of the substrate and forming a second portion in the surface of the substrate having an extension in a plane situated lower than or above a plane of the surface of the substrate, wherein the first and the second portion are separated by a predetermined distance forming a gap, and wherein the step of digital printing a décor comprises digital printing the décor on the surface of the substrate, said first portion and said second portion by the common print bar, dividing the substrate at said gap for forming a first panel and a second panel, and forming a mechanical locking system at said gap, wherein when the first panel and the second panel are joined by the mechanical locking system, the décor on said first portion is synchronized with the décor on said second portion such that the décor of the first portion continuously extends into the décor of the second portion.

19. The method according to claim 18, wherein no décor is printed in the gap.

20. The method according to claim 18, wherein the first portion is provided along an edge of the first panel and the second portion is provided along an edge of the second panel.

21. A building panel, comprising a substrate having a surface, at least one portion in the surface of the substrate having an extension in a plane situated lower than or above a plane of the surface of the substrate, wherein the surface and said at least one portion are provided with a décor, wherein the décor is continuously extending over the surface of the substrate and said at least one portion, wherein the décor is prepared by digital printing on the surface of the substrate and on said at least one portion by at least one common print bar of a single-pass printer, wherein the common print bar is fixedly arranged at least 2 mm above the surface of the substrate, wherein the common print bar comprises print heads with a drop volume between 10-30 picoliters.

22. A method of forming a décor on a substrate, comprising providing a substrate having a surface, digital printing a décor on a first portion and a second portion of said surface, wherein the first and second portions are separated by a predetermined distance forming a gap, and dividing the substrate at the gap to form a first panel and a second panel and forming a mechanical locking system from a portion of the gap, wherein the décor of the first portion is synchronized with the décor of the second portion and continuously extends into the décor of the second portion when the first portion is placed adjacent to the second portion.

23. The method according to claim 22, wherein the décor on the first portion and second portion is printed by at least one common print bar.

24. The method according to claim 22, wherein no décor is printed in the gap.

25. The method according to claim 22, further comprising connecting the first and the second panel by means of the mechanical locking system, wherein the décor of the first portion is synchronized with the décor of the second portion and continuously extends into the décor of the second portion after joining.

26. The method according to claim 23, wherein a position of the at least one common print bar is in a fixed vertical direction during printing.

27. The method according to claim 23, wherein the at least one common print bar is fixedly arranged.

28. The method according to claim 23, wherein a drop velocity of print heads of the at least one common print bar exceeds 8 m/s.

29. The method according to claim 23, wherein a drop volume of print heads of the at least one common print bar is 10-30 picolitres.

30. The method according to claim 23, wherein the at least one common print bar comprises one or several Piezo print heads.

31. The method according to claim 22, wherein said surface comprises a wood veneer, solid wood, a wood-based material, a thermoplastic foil, a co-extruded thermoplastic layer, paper, non-woven.

32. The method according to claim 22, wherein the predetermined distance corresponds to a horizontal extension of the mechanical locking system.

33. A set of building panels, comprising a first panel and a second panel, wherein the first panel and the second panel are provided with a digitally printed décor, wherein the first panel and the second panel further comprise a mechanical locking system formed from a gap between the first and second panel, and wherein the décor of the first panel and the décor of the second panel are synchronized such that the décor is continuously extending over the first panel to the second panel when the first and second panels are joined, wherein the décor is prepared by digital printing on the surface of the first panel and the second panel and on at least one portion of the first and second panels by at least one common print bar, wherein the at least one portion has an extension into a plane situated lower than or above a plane of the surface of the first and second panels.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will by way of example be described in more detail with reference to the appended schematic drawings, which show embodiments of the present invention.

(2) FIG. 1 shows a printing line for printing a décor on a substrate.

(3) FIG. 2 shows a digitally printed substrate according to an embodiment.

(4) FIG. 3 shows a digitally printed substrate according to an embodiment.

(5) FIG. 4 shows a digitally printed substrate according to an embodiment.

(6) FIG. 5 shows a digitally printed substrate according to an embodiment.

(7) FIG. 6 shows a digitally printed substrate according to an embodiment.

(8) FIG. 7 shows a set of building panels joined together according to an embodiment of the invention.

DETAILED DESCRIPTION

(9) In the description below, all directions are related to when a substrate is arranged such that the substrate has a main extension in a horizontal plane.

(10) FIG. 1 illustrates a method of forming a décor on a substrate 1. The method comprises providing the substrate 1 having a surface 2. The surface 2 may comprise a wood veneer, solid wood, a wood-based material, a thermoplastic foil, a co-extruded thermoplastic layer, a paper, non-woven, wallpaper, etc. The substrate 1 may be solid, or may comprise a surface layer and a core, wherein the surface layer is arranged on the core and forms the surface of the substrate. The core may comprise be a wood-based board, for example, a wood-fibre based board such as MDF or HDF, or plywood. The core may be a Wood Plastic Composite (WPC). The core may be a mineral composite board. The core may be a fibre cement board. The core may be magnesium oxide cement board. The core may be a plastic board such as a thermoplastic board. The core may be formed of solid wood. Examples of suitable thermoplastic materials for the surface and/or the core is polyvinyl chloride (PVC), polypropylene (PP), and/or polyethylene (PE).

(11) The substrate 1 may be a board prepared for printing, for example, a wood-based board with a surface coated with a layer adapted to receive a print.

(12) Prior to printing on the surface 2 of the substrate 1, at least one portion in the surface 2 of the substrate 1 having an extension in a plane situated lower than a plane of the surface 2 of the substrate 1 is formed. The at least one portion may comprise a portion being inclined in relation to the surface 2 of the substrate 1. At least one component of said portion has an extension in a plane lower than the plane of the surface 2 of the substrate 1. A portion being inclined includes a component having an extension in a plane lower than the plane of the surface 2 of the substrate 1. The at least one portion may be bevel, an embossed portion, a grout line, etc., which will be described in more detail with reference to FIGS. 2-7.

(13) The at least one portion may be formed by any method (not shown) such as pressing, embossing, brushing, machining, profiling, sanding, scarping, or any other type of machining prior to printing on the surface of the substrate.

(14) By printing at a distance from the substrate 1 being larger than conventional, the substrate may be brushed prior to printing. Any fibre swelling will not disturb the printing operation.

(15) In FIG. 1, a printing line for printing a décor on a substrate 1 is shown, arranged after said at least one portion has been formed. The printing line comprises a conveyor 70 and a digital printer 80. The conveyor 70 is adapted to convey a substrate 1 through the printer 80. Optionally, the printing line may comprise a primer application device (not shown) adapted to apply a primer on the surface 2 of the substrate 1 prior to printing. The printing line may further comprise a heating device 90 adapted to heat the substrate 1 after printing. The printing line may further comprise a device for providing the substrate 1 with a protective layer or coating (not shown) after the printing.

(16) The printer 80 may be an inkjet printer. Preferably, the printer is a DOD (Drop on Demand) piezo-electric inkjet printer. A thermal DOD inkjet printer may also be used. The décor is printed in a contactless manner.

(17) The printer 80 comprises at least one print bar 81, 82, 83, 84. The print bar 81, 82, 83, 84 comprises at least one inkjet print head. Preferably, the printer 80 comprises several inkjet print heads. Preferably, the printer 80 comprises several print bars 81, 82, 83, 84. As an example, the printer 80 may comprise one print bar for each one of the CMYK colours, and/or one print bar for each spot colour. The number of print bars, print heads, and spot colours may vary.

(18) The print bar or print bars 81, 82, 83, 84 is arranged on a fixed distance from the conveyor in a vertical direction. Thereby, the print bar or print bars 81, 82, 83, 84 is also arranged on a fixed distance from the surface 2 of the substrate 1 arranged on the conveyor 70.

(19) Preferably, a number of print heads are arranged one after the other in a print bar 81, 82, 83, 84 extending perpendicular to the conveying direction D of the substrate 1 through printer. Print heads arranged in the same print bar 81, 82, 83, 84 preferably includes ink having the same colour. The width of the print bar 81, 82, 83, 84 preferably corresponds to the width of the substrate 1 on which the décor is to be printed. The print bars 81, 82, 83 and 84 are preferably stationary.

(20) In the shown digital printer 80, a first, second, third and fourth print bar 81, 82, 83, 84 are arranged one after each other in the conveying direction D of the substrate. A first colour is applied by the print heads of the first print bar 81, a second colour is applied by the print heads of the second print bar 82, a third colour is applied by the print heads of the third print bar 83, and a fourth colour is applied by the print heads of the fourth print bar 84.

(21) Alternatively, a printer 80 comprising a print head having different channels may be used. In this case, one print head may print one colour or several colours. Thereby, more than one colour can be printed by an individual print head provided with different channels. One channel is provided for each colour. Consequently, only the printer 80 may comprise only one print bar comprises several print colours.

(22) The ink that is applied by means of the above described inkjet printer 80 may be an aqueous ink, a solvent-borne ink, or a UV based ink. The ink may be a pigment based ink or a dye based ink.

(23) The ink that is applied by means of the above described inkjet printer 80 may be an aqueous pigment ink composition. The ink composition comprises pigments giving the ink its specific colour. Preferably, the aqueous ink composition is a heat activated curing ink. The ink composition may comprise a binder, water and pigment. The binder may for example be a polymer or cellulose. The binder may be dispersed in the ink composition. Alternatively, the pigment is coated by a binder, preferably a polymer. The polymer may carry carboxyl groups. The polymer may be styrene, acrylic or methacrylic polymer or copolymer, or unsaturated monomers, polyesters, vinyl polymers or copolymers, aromatic and aliphatic polyurethanes, or alkyd resins.

(24) The décor that is to be printed on the substrate 1 may be both natural designs and patterns such as a wood pattern or stone pattern. The décor may also be a fantasy design or pattern.

(25) The inkjet printer 80 is adapted to print a décor on the substrate 1. A primer may be applied on the substrate prior to printing.

(26) The drop velocity of the print heads may be exceeding 8 m/s. It has been identified that 10-30 picolitres will still give an optically good printing result without getting a dotted impression of the print. In order to further improve the stand off, the drop velocity may be increased to 8 m/s or even more. With this it will be possible to jet from a distance of 2 mm and more, even up to 6 mm. The distance may be about 2 mm in the vertical direction form the main plane of the surface, or preferably exceed 2 mm. A drop volume of print heads of the print bar may be 10-30 picolitres. In one embodiment, a drop volume of print heads of the print bar is 10-30 picolitres and the print bar is positioned at a distance of at least 2 mm in a vertical direction from a main plane of the surface. By combining a drop volume of 10-30 picolitres with a distance of at least 2 mm, a sufficient resolution of the print is preserved, as well as the colour tone of the print.

(27) Heat is applied to the print such that the water of the aqueous pigment ink composition evaporates. A heating device 90 may be arranged after the digital printer 80, as seen in the conveying direction D of the substrate 1. The heating device 90 may include infrared (IR) heating, near infrared (NIR) heating, heated air or a combination thereof.

(28) After printing, the substrate 1 may be provided with a protective layer such as a coating, for example, a radiation curable coating, in any conventional manner. The coating may be applied by an ink jet print head (not shown). The coating may be applied by an ink jet print head on said at least one portion such as a bevel, grout line and/embossing. Superfluous coating fluid may be removed from said at least one portion such as a bevel, grout line and/or embossing. Superfluous coating may be removed before and/or after curing. Superfluous coating may be removed, for example, by scarping, sanding, air pressure, etc.

(29) FIG. 2 shows a substrate 1 according to an embodiment of the present invention. The substrate 1 is any type as described above with reference to FIG. 1. The substrate may be a building panel such as a floor panel as shown in FIG. 2. The building panel may comprise a mechanical locking system 4, as in the embodiment shown in FIG. 2.

(30) The substrate 1 comprises at least one embossed portion 3 having an extension in a plane lower than the surface 2 of the substrate 1. The embossed portion 3 may be formed by pressing, brushing and/or embossing as described above with reference to FIG. 1. The embossed portion 3 has been formed prior to printing. The substrate 1 further comprises at least one protrusion 8 having an extension in a plane above the surface 2 of the substrate 1.

(31) A décor is printed on the surface 2 of the substrate 1 by the ink jet printer 80 and method described above with reference to FIG. 1. Preferably, the décor is printed over the whole surface 2 of the substrate 1. The décor is printed in register with the at least one embossed portion 3 and the at least one protrusion 8.

(32) The embossed portion 3 is printed with the décor, and the décor continuously extends over the surface 2 of the substrate 1 and into and over the embossed portion 3. The protrusion 8 is printed with the décor, and the décor continuously extends over the surface 2 of the substrate 1 and into and over the protrusion 8. Portions of both the embossed portion 3 and the protrusion 8 have an extension in the vertical direction as well as in the horizontal direction. By the drop velocity of the ink in the print head exceeding 8 m/s, surfaces positioned at different distances from the print bar 81, 82, 83, 84 has been printed by the same print bar 81, 82, 83, 84 in the same printing operation, without adjusting the distance between the print bar 81, 82, 83, 84 and the surface 2 to be printed. Furthermore, ink drops have also landed on portions having an extension in the vertical direction, such that side surface of the embossed portion 3 also have been printed. Turbulence may further facilitate for the ink drops to bond even on a vertical surfaces.

(33) FIG. 3 shows a substrate 1 according to an embodiment of the present invention. The substrate 1 is any type as described above with reference to FIG. 1. The substrate may be a building panel such as a floor panel as shown in FIG. 3. The building panel may comprise a mechanical locking system 4, as in the embodiment shown in FIG. 3.

(34) The substrate 1 comprises a grout line 7 having an extension in a plane lower than the surface 2 of the substrate 1. The grout line 7 may have a circular, rectangular, U-shaped or V-shaped shape as seen in cross section. The grout line 7 may be formed by pressing or any kind of machining as described above with reference to FIG. 1. The grout line 7 has been formed prior to printing. Preferably, the grout line 7 extends along at least one edge of the substrate 1.

(35) A décor is printed on the surface 2 of the substrate 1 by the printer and method described above with reference to FIG. 1. Preferably, the décor is printed over the whole surface 2 of the substrate 1.

(36) The grout line 7 is printed with the décor, and the décor continuously extends over the surface 2 of the substrate 1 and into and over the grout line 7. Both portions of the grout line 7 have an extension in the vertical direction as well as in the horizontal direction. By the drop velocity of the ink in the print head exceeding 8 m/s, surfaces positioned at different distances from the print bar 81, 82, 83, 84 has been printed by the same print bar in the same printing operation, without adjusting the distance between the print bar and the surface 2 to be printed. Furthermore, ink drops have also landed on portions having an extension in the vertical direction, such that side surface of the grout line also have been printed. Turbulence may further facilitate for the ink drops to bond on a vertical surfaces.

(37) FIG. 4 shows a substrate 1 according to an embodiment of the present invention. The substrate 1 is any type as described above with reference to FIG. 1. The substrate may be a building panel such as a floor panel as shown in FIG. 4. The building panel may comprise a mechanical locking system 4, as in the embodiment shown in FIG. 4.

(38) The substrate 1 comprises a bevel 11 having an extension in a plane lower than the surface 2 of the substrate 1. The bevel 11 is preferably formed along at least one edge of the substrate 1. The bevel 11 may have a convex shape. The bevel 11 may be formed by pressing or any kind of machining as described above with reference to FIG. 1. The bevel 11 has been formed prior to printing.

(39) A décor is printed on the surface 2 of the substrate 1 by the ink jet printer 80 and method described above with reference to FIG. 1. Preferably, the décor is printed over the whole surface 2 of the substrate 1.

(40) The bevel 11 is printed with the décor, and the décor continuously extends over the surface 2 of the substrate 1 and over the bevel 11. By the drop velocity of the ink in the print head exceeding 8 m/s, surfaces positioned at different distances from the print bar 81, 82, 83, 84 has been printed by the same print bar in the same printing operation, without adjusting the distance between the print bar and the surface 2 to be printed.

(41) FIG. 5 shows a substrate 1 according to an embodiment of the present invention. The substrate 1 is any type as described above with reference to FIG. 1. The substrate may be a building panel such as a floor panel, a wall panel, a ceiling panel, a furniture component, worktop, etc. The substrate 1 comprises a mechanical locking system 4. The mechanical locking system 4 may comprise at least a tongue 5 along a first edge of the substrate 1 and a tongue groove 6 along a second edge of the substrate 1. In the embodiment shown in FIG. 5, the first edge and the second edge are arranged opposite each other. The mechanical locking system 4 is formed prior to printing the substrate.

(42) The substrate 1 further comprises a first bevel 11 extending along the first edge of the substrate 1. The substrate 1 further comprises a second bevel 12 extending along the second edge of the substrate 1. The bevels 11, 12 have an extension in a plane lower than the surface 2 of the substrate 1. The bevels 11, 12 have a convex shape. The bevels 11, 12 are preferably formed along one edge of the substrate 1. The bevels 11, 12 may be formed by pressing or any kind of machining as described above with reference to FIG. 1. The bevels 11, 12 have been formed prior to printing.

(43) A décor is printed on the surface 2 of the substrate 1 by the inkjet printer 80 and method described above with reference to FIG. 1. Preferably, the décor is printed over the whole surface 2 of the substrate 1.

(44) The bevels 11, 12 are printed with the décor, and the décor continuously extends from the first bevel 11 over the surface 2 of the substrate 1 and to and over the second bevel 12. By the drop velocity of the ink in the print head exceeding 8 m/s, surfaces positioned at different distances from the print bar 81, 82, 83, 84 has been printed by the same print bar in the same printing operation, without adjusting the distance between the print bar 81, 82, 83, 84 and the surface 2 to be printed.

(45) Furthermore, the décor continuously extends over the first bevel 11 and into and over the tongue 5 at the first edge in the embodiment shown in FIG. 5. Preferably, at least some ink drops have landed on an edge surface of the first edge extending in the vertical direction. In an embodiment wherein the substrate 1 comprises a surface layer of wood veneer arranged on wood-based board, and wherein the tongue 5 is formed in the wood-based board, by the décor extending over the tongue 5, a visual impression of a solid substrate 1 may be formed.

(46) A person skilled in the art appreciates that embodiments described above with reference to FIGS. 2-5 may be combined. A person skilled in the art also appreciates that the décor may extend over the tongue 5 of the mechanical locking system without requirement of a bevel 11, 12.

(47) FIG. 6 illustrates a method of forming a décor on substrate 1 intended to form at least two building panels 10, 20, 30. The building panels 10, 20, 30 may be floor panels, wall panels, ceiling panels, door panels, furniture components, etc. The method comprises providing a substrate 1 having a surface 2. The surface 2 may comprise a wood veneer, solid wood, a wood-based material, a thermoplastic foil, a co-extruded thermoplastic layer, a paper, non-woven, wallpaper, etc. The substrate 1 may be solid, or may comprise a surface layer and a core, wherein the surface layer is arranged on the core and forms the surface of the substrate. The core may comprise be a wood-based board, for example, a wood-fibre based board such as MDF or HDF, or plywood. The core may be a Wood Plastic Composite (WPC). The core may be a mineral composite board. The core may be a fibre cement board. The core may be magnesium oxide cement board. The core may be a plastic board such as a thermoplastic board. The core may be formed of solid wood. The core may be a lamella core. Examples of suitable thermoplastic materials for the surface and/or the core is polyvinyl chloride (PVC), polypropylene (PP), and/or polyethylene (PE).

(48) The substrate 1 may be a board prepared for printing, for example, a wood-based board with a surface coated with a layer adapted to receive a print.

(49) The method may comprise forming bevels (not shown) as described above with reference to FIG. 5, such as a first bevel and a second bevel separated by a predetermined distance forming a gap 19 between the first and the second bevel. Preferably, the first and second bevels are extending parallel with each other. The bevels may be formed by any conventional method such as pressing, embossing, machining, profiling, sanding, scarping, or any other type of machining.

(50) A décor is printed by an inkjet printer 80 as described above with reference to FIG. 1. The décor is printed on the surface 2 of the substrate 1 adapted form a surface 100 of a first panel 10 and a surface 200 of a second panel 20. The portions of the surface 2 of the substrate 1 adapted to form the surface 100 of the first panel 10 and the surface 200 of the second panel 20, respectively, are separated by a gap 19. The décor printed on a second portion 12 of the first panel 10 is synchronized with a first portion 21 of the second panel 20. The décor is printed by a common print bar 81, 82, 83, 84 as described above with reference to FIG. 1. The print bar 81, 82, 83, 84 is arranged on a fixed distance from the surface 2 of the substrate 1. The print bar 81, 82, 83, 84 may be stationary. By the drop velocity of the ink in the print head exceeding 8 m/s, surfaces positioned at different distances from the print bar 81, 82, 83, 84 has been printed by the same print bar in the same printing operation, without adjusting the distance between the print bar and the surface to be printed.

(51) The décor continuously extends over the surface 2 of the substrate adapted to form the surface 100 of the first panel 10 to the second portion 12. Further, the décor of the second portion 12 is synchronized with the décor of the first portion 21, and further the décor of the surface 2 of the substrate 1 adapted to form the surface 200 of the second panel 20. No décor may be present in the gap 19. The width of the gap 19 may correspond to the width required to form a mechanical locking system 4. After the décor has been printed, a first panel 10 and a second panel 20 may be formed by dividing the substrate 1 at the gap 19, such that a first and a second panels 10, 20 are formed. When the first panel 10 and the second panel 20 are arranged adjacent each other, the second edge portion 12 to the first edge portion 21, the décor continuously extends from the surface 100 of the first panel 10 to the surface 200 of the second panel 20 via the first and the second edge portions 21, 12, as shown in FIG. 7a. The décor of the second edge portion 12 is synchronized with the décor of the first edge portion 21.

(52) The method may further comprise forming a mechanical locking system 4 at said gap 19. The mechanical locking system 4 may be of different types. The mechanical locking system 4 may comprise a tongue 5 at said first edge and tongue groove 6 at said second edge adapted to lock the first and second panels 10, 20 in a vertical direction. The mechanical locking system 4 may comprise a tongue 5 at said first edge adapted to cooperate with a tongue groove 6 at said second edge for locking the panels in a vertical direction, and locking strip at said second edge adapted to cooperate with a locking groove at said first edge (not shown). Alternatively, the mechanical locking system may comprise a separate flexible tongue (not shown). The mechanical locking system may be any of the types disclosed in WO 2007/015669, WO 2008/004960, WO 2009/116926, or WO 2010/087752. The panels 10, 20 may be provided with a mechanical locking system along long edges only, or along both long edges and short edges.

(53) When the first and the second panel 10, 20 are joined by means of the mechanical locking system 4, the second edge portion 12 to the first edge portion 21, as shown in FIG. 7a, the décor continuously extends from the surface of the first panel 10 to the surface of the second panel 20 via the second and the first edge portions 12, 21, as shown in FIG. 7a. The décor of the second edge portion 12 of the first panel 10 is synchronized with the décor of the first edge portion 21 of the second panel 20. The first and second panels 10, 20 may also be provided with bevels (not shown), wherein a décor of a bevel along the second edge portion 12 of the first panel 10 is synchronized with a décor of a bevel along the first edge portion 21 of the first panel 20.

(54) In the embodiment shown in FIG. 7b, the décor of the first panel 10 is synchronized along all four edge portions of the panel 10. The set of building panels shown in FIG. 7b comprises the first and the second panel 10, 20 described above with reference to FIG. 7a, a third panel 30, a fourth panel 40 and a fifth panel 50, wherein the third, fourth and fifth panel 30, 40, 50 are of the same type as the first and second panel 10, 20 described above. The third panel 30 comprises a third edge portion 33 of the third panel 30. The fourth panel 40 comprises a fourth edge portion 44 of the fourth panel 40. The fifth panel 50 comprises a second edge portion 51 of the fifth panel 50. All edge portions are printed with the décor. The décor of the first edge portion 11 of the first panel 10 is synchronized with the décor of the second edge portion 51 of the second panel 50. The décor of the second edge portion 12 of the first panel 10 is synchronized with the décor of the first edge portion 21 of the fifth panel 20. The décor of the third edge portion 13 of the first panel 10 is synchronized with the décor of the fourth edge portion 44 of the fourth panel 40. The décor of the fourth edge portion 14 of the first panel 10 is synchronized with the décor of the third edge portion 33 of the third panel 30. As shown in FIG. 7 b, when joined, the décor continuously extends from the first panel 10 over to the second, third, fourth and fifth panel 20, 30, 40, 50.

(55) In the embodiment shown in FIG. 7b, the first and second edges portions are long edges of the panels, and the third and fourth edges portions are short edges of the panels.

(56) The edge portions 11, 12, 13, 14, 22, 33, 44, 51 may also be provided with bevels (not shown) along the edge portions.

(57) A person skilled in the art appreciates that the panels joined together in FIGS. 7a-b may also been produced individually as disclosed above with reference to FIG. 1 as well as been produced by the method described with reference to FIG. 6.

(58) It is contemplated that there are numerous modifications of the embodiments described herein, which are still within the scope of the invention as defined by the appended claims. For example, it is contemplated that the panels and/or on the package may be provided with a sign indicating which panels match.

(59) For example, it is contemplated that the mechanical locking system described above may be adapted to lock in a vertical direction only, or lock in a vertical and horizontal direction.

Example 1

(60) A building panel comprising a HDF core and a maple veneer having a thickness of 2 mm arranged on the HDF core was provided. The building panel comprises a mechanical locking system along the edges. At the long side edges, bevels having a concave shape were arranged adjacent the mechanical locking system. The bevels have a depth of 2 mm, i.e. extending into the entire thickness of the maple veneer. The surface of the maple veneer was provided with embossed portions having a depth of maximum 1 mm. The distance in the vertical direction from the highest protruding portions of the surface to the print heads was 3 mm, i.e. the stand off was 3 mm from the highest located portions.

(61) A décor file was printed over the surface of the maple veneer, including embossed portions and protruding portions and the bevels at the long side edges. The décor was printed by a single-pass printer and with a drop volume of the print heads of 10-30 picolitres.

(62) A high quality print was obtained, with desired resolution and colour tone. At the deepest located embossed portions (located at a vertical distance of 5 mm from the print heads), a slight colour tone shift towards the darker range was noticed.

Example 2

(63) A set of building panels were provided, each comprising a HDF core and a maple veneer having a thickness of 2 mm arranged on the HDF core. The building panels were joined to each other, long side edge to long side, by means of a mechanical locking system. The long side edges of the panels were provided with bevels having a concave shape and a depth of 2 mm, i.e. extending into the entire thickness of the maple veneer.

(64) A décor including a logotype was printed on the surface of both panels, including the bevels. The décor including the logotype was printed such that the logotype was continuously extending from the surface of the first panel, over the bevel of the first panel to the bevel of the second panel and over the surface of the second panel. Thereby, the logotype was continuously extending over the panels and the joined long side edges of the panels, such that an impression of a single panel is obtained. The décor including the logotype was printed by a single-pass printer and with a drop volume of the print heads of 10-30 picolitres.