METHOD AND DEVICE FOR COATING A SURFACE

Abstract

The invention relates to a method and a device for coating a surface of an object, in particular a narrow side of a plate-shaped workpiece. The device and method can be used, for example, in the field of the furniture and components industry.

Claims

1. A method for coating a surface of a workpiece, the method comprising the steps of: applying a first layer, the first layer having a first pattern, and applying a second layer to the first layer, the second layer having a second pattern.

2. The method according to claim 1, wherein the first pattern or the second pattern is formed by gaps in the layer.

3. The method according to claim 1, wherein the surface of the workpiece is a surface of a coating material.

4. The method according to claim 1, wherein at least one of the applying the first layer or the applying the second layer is carried out with a UV ink or a UV varnish, or a solvent-based or water-based ink or varnish.

5. The method according to claim 1, wherein at least one of the applying the first layer or the second layer is carried out in one pass.

6. The method according to claim 1, wherein after application of the first layer, an action is performed on the first layer to at least partially cure or dry the first layer.

7. The method according to claim 1, wherein at least one of the applying the first layer or the applying the second layer is carried out with inkjet print head.

8. The method according to claim 1, further comprising setting parameters for application of the first and second layers, wherein the parameters comprise at least one of: droplet spacing, droplet size, type of voltage pulse at the print head, opening time of a nozzle, opening cross section of a nozzle, pressure for ejecting a material for forming the first and/or second layer, or selection of a material for forming the first or second layer.

9. The method according to claim 1, wherein a layer material of the first layer and a layer material of the second layer differ from each other.

10. A device for coating a surface of a workpiece, the device comprising: a first application device for applying a first layer, a second application device for applying a second layer to the first layer; and a control device configured to control the first application device to form the first layer with a first pattern and to control the second application device to form the second layer with a second pattern.

11. The method according to claim 1, wherein the surface comprises a narrow side of a plate-shaped workpiece, and the coating material comprises a strip-shaped coating material.

12. The method according to claim 6, wherein the action comprises at least partially curing or drying the first layer an air dryer, an IR lamp, or a UV lamp.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Further features and advantages of a device, a use and/or a method are apparent from the following description of embodiments with reference to the accompanying figures.

[0032] FIG. 1 is a perspective view of an embodiment of device for coating a surface.

[0033] FIG. 2a schematically shows a first example of a coating of a surface.

[0034] FIG. 2b schematically shows a second example of a coating of a surface.

DESCRIPTION OF EMBODIMENTS

[0035] Identical reference numbers that are used in different figures designate identical, corresponding or functionally similar elements.

[0036] FIG. 1 shows a perspective view of an embodiment of a device for coating a surface of a plate-shaped workpiece 100. The plate-shaped workpiece 100 is provided with a strip-shaped coating material 101 and is moved in a throughput direction by means of a conveying device (not shown).

[0037] As the workpiece 100 moves, it enters the region of a first application device 10, which is configured as an inkjet print head. A first layer is applied to the surface of the strip-shaped coating material 101 by the first application device 10.

[0038] After application of the first layer by means of the first application device 10, this area of the workpiece 100 enters the region of a UV lamp 20, which is configured to at least partially cure the first layer that is formed by a UV ink or a UV varnish. The structure/shape of the first layer is thus fixed in a defined manner before the second layer is applied. The UV lamp 20 in particular shortens the curing time.

[0039] The area provided with the first layer is then guided into the region of a second application device 30, which is also designed as an inkjet print head and is configured to apply a second layer.

[0040] A processing result that can be achieved with the device shown in FIG. 1 can lead to different designs of the applied layer, as is shown in FIGS. 2a and 2b.

[0041] In the embodiment example shown in FIG. 2a, the first layer S1 comprises various gaps. The second layer S2 is applied to the first layer S1 in such a manner that gaps are also formed by the second layer S2, but these gaps are larger than the gaps of the first layer S1. A specific reflection behaviour of the light radiation impinging on the coated surface can be achieved in this manner, which makes a surface appear relatively matte.

[0042] FIG. 2b shows a further embodiment, in which a first layer S1 and a second layer S2 are applied to the coating material 101 provided on the workpiece 100. As compared to the first embodiment example in FIG. 2a, the second layer S2 also comprises gaps, but the layer portions of the second layer S2 are arranged such that an edge region of the layer portions of the second layer S2, as viewed in cross section, is aligned with an edge region of the gaps of the first layer S1. This leads to the formation of comparatively deep structures, which results in the surface appearing comparatively glossy.

[0043] Even though it is described in the context of the present embodiment that the workpiece is supposed to be moved in a throughput direction by means of a conveying device, the workpiece can, according to a further embodiment, also be fixed at least temporarily while a first and second application device as well as a UV lamp, which are combined, for example, in a movable unit, are moved.

[0044] Even though a UV lamp is described in the context of the embodiment, with which the first layer can be at least partially cured, it is provided according to a further modification that a hot air dryer and/or an IR lamp is used instead of the UV lamp or in addition thereto. By means of an air dryer or an IR lamp, solvent-based or water-based inks and varnishes can be acted upon in order to fix the first layer formed by such an ink or varnish, and thus the corresponding pattern.

[0045] It is apparent to the person skilled in the art that individual features described in different embodiments can also be implemented in a single embodiment, provided that they are not structurally incompatible. Similarly, various features described in the context of a single embodiment may also be provided in several embodiments either individually or in any suitable sub-combination.