Component with Surface Structure Generated by Embossing and Method for the Production Thereof

Abstract

The invention relates to a component having a plate-shaped or profile-shaped support and a decorative surface layer connected to the support, the surface layer being formed of thermally curable resin and comprising a three-dimensional surface structure that is produced by embossing and is irregular. According to the invention, in order to inexpensively obtain a decorative surface which has good wear resistance and largely prevents disturbing finger prints, the surface structure comprises regions that are alternately ordered and non-ordered and that are formed by a ribbed and/or grooved structure, ordered regions having parallel and/or quasi-parallel ribs and/or parallel and/or quasi-parallel grooves being interrupted by non-ordered regions or structural breaks, and the width of the respective rib or groove being in the range of from 0.5 μm to 100 μm. Furthermore, a method for manufacturing a component of this type using a corresponding embossing tool is disclosed and claimed.

Claims

1. A component having a plate-shaped or profile-shaped support and a decorative surface layer connected to the support, whereby the support comprises at least one of a wood material, a high pressure laminate (HPL) and a cardboard and the surface layer comprises a thermally curable resin and a three-dimensional surface structure that is produced by embossing and is irregular, wherein the surface structure comprises regions that are alternately ordered and non-ordered and that are formed by a ribbed or a grooved texture, the ordered regions having parallel or quasi-parallel ribs and parallel or quasi-parallel grooves being interrupted by the non-ordered regions or by structural breaks, and wherein a width of the respective rib or groove being between 0.5 μm to 100 μm.

2. The component according to claim 1, wherein the width of the respective rib or groove is in the range of from 2 μm to 50 μm.

3. The component according to claim 1, wherein the respective rib has a maximum height of 15 μm.

4. The component according to claim 1, wherein the respective groove has a maximum depth of 15 μm.

5. The component according to claim 1, wherein the ribs comprise round rib ridges.

6. The component according to claim 1, wherein the surface layer is formed of melamine resin, urea resin or a mixture of such resins.

7. A method for manufacturing a component having a plate-shaped or profile-shaped support, whereby the support comprises at least one of a wood material, a high pressure laminate (HPL) and a cardboard, the method comprising: coating the support with a decorative surface layer, the surface layer comprising a thermally curable resin and a three-dimensional, irregular surface structure; and embossing into the surface layer, wherein an embossing tool is used to emboss the surface layer, of which the embossing tool the embossing surface comprises regions that are alternately ordered and non-ordered and that are formed by a ribbed or grooved structure, the ordered regions having parallel or quasi-parallel ribs and parallel or quasi-parallel grooves being interrupted by the non-ordered regions or by structural breaks, and wherein a width of the respective rib or groove being between 0.5 μm to 100 μm.

8. The method according to claim 7, wherein the width of the respective rib or groove is between 2 μm to 50 μm.

9. the method according to claim 7, wherein the respective rib has a maximum height of 15 μm.

10. The method according to claim 7, wherein the respective groove has a maximum depth of 15 μm.

11. The method according to claim 7, wherein the ribs comprise round rib ridges.

12. The method according to claim 7, wherein the surface layer is formed of melamine resin, urea resin or a mixture of such resins.

13. The method according to claim 7, wherein the embossing surface is produced by laser engraving, the grooves being burnt into a metal tool surface and the tool surface being chrome-plated after the grooves have been burnt in.

14. The method according to claim 7, wherein the embossing surface is produced by laser engraving, the grooves being burnt into a chrome-plated metal tool surface.

15. The method according to claim 7, wherein the embossing surface is produced by selectively burning away an etching paint applied all over a tool surface, an etching mask thus produced then being subjected to an etching process in order to produce the grooves having a desired depth.

16. The component according to claim 3, wherein the respective rib has a maximum height of 10 μm.

17. The component according to claim 4, wherein the respective groove has a maximum depth of 10 μm.

18. A method according to claim 9, wherein the respective rib has a maximum height of 10 μm.

19. A method according to claim 10, wherein the respective groove has a maximum depth of 10 μm.

Description

[0026] The invention will be described in more detail in the following with reference to the accompanying drawings and on the basis of a plurality of embodiments. In the drawings:

[0027] FIGS. 1 to 3 are images of portions of a surface structure of a component according to the invention, which have been taken by an atomic force microscope at different magnifications;

[0028] FIGS. 4 and 5 show two examples of structural images which have been produced using algorithms;

[0029] FIG. 6 is an example of a technically generated structural image derived from a ripple finish texture;

[0030] FIG. 7 is an example of a random structural image that is derived from a ripple finish texture and has been produced by means of a laser; and

[0031] FIGS. 8 to 11 are further examples of technically generated structural images which are each derived from a ripple finish texture.

[0032] Atomic force microscopy (AFM) is a surface-sensitive technique for imaging the texture and morphology or topography of the surface of a sample. In this case, the surfaces of the samples to be analysed are scanned using a measuring probe and the interaction between the probe and the sample surface is mapped. The measurement probe, also referred to as a cantilever, comprises a resilient portion which acts as the reflective surface for a laser beam. In this case, the laser beam is deflected at different angles depending on the resilient deformation of the cantilever and the reflected, deflected laser beam is detected by a photodetector. The resilient deformation of the cantilever and thus the deflection of the laser beam depend on the height profile of the sample surface. When the sample surface is scanned, each point in the xy plane is assigned a brightness value depending on the extent of the deflection of the laser beam and thus an image of the surface profile of the sample is produced on the screen of the atomic force microscope. The movement of the cantilever in the z direction (distance from the surface) is also detected.

[0033] FIGS. 1 to 3 show images at different magnifications of surface portions of a sample of a component according to the invention analysed by an atomic force microscope. The component, which is for example a furniture board or a wall panel, comprises a plate-shaped support which is coated on one or both sides with a decorative surface layer. The support and the decorative surface layer are integrally bonded together. The decorative surface layer is formed of thermally curable resin, preferably melamine resin and/or urea resin, the resin being provided on at least the top of the decorative surface layer.

[0034] A three-dimensional, irregular surface structure is embossed into the surface layer or the resin layer by means of a structured embossing tool, for example a structured pressure plate or pressure belt.

[0035] It can be seen in FIG. (images) 1 to 3 that the surface structure comprises irregularly meander-shaped ribs 1 and grooves 2, of which some extend transversely to one another and some are adjacent to one another in a substantially contour-compliant manner. The ribs and/or grooves that extend transversely to one another enclose angles of different sizes, in particular in the range of from 30° to 150°. The adjacent, contour-compliant ribs 1′ and/or grooves 2′ have a substantially identical curve shape.

[0036] The ribs 1, 1′ and grooves 2, 2′ are formed so as to be very fine, in particular very narrow. The width of the respective rib 1, 1′ or groove 2, 2′ is in the range of from 0.5 μm to 100 μm, preferably in the range of from 2 μm to 50 μm. The height or depth of the ribs 1, 1′ or grooves 2, 2′ is in the range of from 0.5 μm to 15 μm, preferably in the range of from 0.5 μm to 10 μm, particularly preferably in the range of from 0.5 μm to 8 μm. The ridge length of individual meander-shaped ribs 1, 1′ or the trough length of individual meander-shaped grooves 2, 2′ of the surface structure is for example in the range of from 10 μm to 500 μm, in particular in the range of from 20 μm to 200 μm.

[0037] The different structural regions (structural units) of the surface result in different indices of refraction or reflectances and thus the effect of the at least partial non-visibility of fingerprints. The variation in the fineness of these surface structures determines both the degree of matting and the anti-fingerprint properties in connection with the selected type of structuring. The finer the three-dimensional surface structure in the form of ribs and/or grooves in the above-mentioned regions, the smaller the degree of gloss of the surface. The rougher the surface structure in the above-mentioned regions, the better the anti-fingerprint properties. The rib ridges of the ribs 1, 1′ are well rounded when viewed in cross section. The ribs 1, 1′ comprise a substantially parabolic or substantially semi-circular cross-sectional contour, for example. The same also preferably applies to the cross-sectional contour of the grooves 2, 2′.

[0038] In order to manufacture components having a decorative surface, of which the decorative surface has a good wear resistance and largely prevents objectionable fingerprints, the invention thus provides that the structural characteristics of a ripple finish surface, i.e. a sequence of more ordered and more non-ordered structural elements in the micrometre range, are embossed or pressed into a surface layer made of thermally curable resin. For this purpose, textural images produced in a technically controlled manner can be preferably also used by the textural image being incorporated into the surface of an embossing tool, for example a pressure plate, or being used as a template for manufacturing the die surface (embossing surface). In this case, as textural images produced in a controlled manner, in particular such textural images can be used which are produced by an algorithm and/or from fractal and/or replicated pattern sequences. In this regard, a number of examples are shown in FIGS. 4 to 11.

[0039] FIG. 4 shows a structural image generated by means of one or more differential equations, while FIG. 5 illustrates a fractured structural formation based on a vector graphic. FIG. 6 shows a technically simple alternation of ordered and non-ordered textural elements or structures, the non-ordered textural elements (structures) defining a textural break (interruption). FIG. 7 shows an image of a random pattern produced by a laser beam and having more ordered and more non-ordered structural elements in the form of grooves or ribs.

[0040] FIGS. 8 to 11 show patterns derived from ripple finish textures which have similar characteristics to ripple finish textures, specifically a sequence of (relatively) ordered or more ordered and non-ordered or less ordered structural elements, in turn FIG. 8 showing a non-ordered texture, FIG. 9 showing a lamellar or strip-like structure having a plurality of strip-like structural elements, FIG. 10 showing a “peanut” structure having a plurality of peanut-shaped structural elements, and FIG. 11 showing a structure having a plurality of hexagonal structural elements.

[0041] An embossing tool suitable for producing one of the structural images shown in FIGS. 1 to 11 or a corresponding surface structure, for example a textured pressure plate or a textured press roll, can be manufactured by laser machining (laser engraving) the die surface (embossing surface).

[0042] One embodiment of the laser engraving of a metal tool surface for producing surface structures according to the invention in surface layers made of thermally curable resin, in particular melamine resin, is characterised in that the grooves or structures required for this purpose are burnt directly into the metal tool surface, which is preferably made of steel, and the tool surface is chrome-plated after the grooves or structures have been burnt in. Etching the die surface in order to produce the grooves (structures) is not required in this case. The pressure plates or press rolls textured by the direct laser engraving can be inserted immediately after a final chrome-plating step. In this case, no matt chromium needs to be used in order to reduce the degree of gloss of the embossing surfaces of the press surfaces or press rolls.

[0043] Another option for manufacturing pressure plates or press rolls having the required microstructures for producing surface structures according to the invention in thermally curable resin layers consists in producing the embossing surface by laser engraving, the grooves being burnt into a chrome-plated metal tool surface. In this case, a subsequent chrome-plating step would not be required. In this case, a rough-polished and sufficiently thickly chrome-plated metal sheet, preferably sheet steel, can be used as the starting material, in which metal sheet the required microstructures can be burnt by means of laser engraving.

[0044] Another variant for manufacturing pressure plates or press rolls having the required microstructures for producing surface structures according to the invention in thermally curable resin layers consists in producing said microstructures by selectively burning away, by means of at least one low-energy laser, an etching paint applied all over the sheet surface or roll sleeve surface. The etching mask thus produced is then subjected to an etching process in order to produce the required grooves having the desired depth in the pressure plate or in the roll sleeve surface.

[0045] The implementation of the present invention is not restricted to the exemplary embodiment shown in the drawings, but rather numerous variants are conceivable which make use of the invention outlined in the accompanying claims even if the design is different from the example.