Method for manufacturing a decorative part

Abstract

Method for manufacturing a decorative part (10) for an interior trim of a motor vehicle, where the decorative part (10) a wood veneer (12) wherein the wood veneer (12) has depressions (16), wherein the depressions (16) are filled with a hardened metal paste (22), wherein the hardened metal paste (22) is provided exclusively in the recesses (16), in which the indentations (16) are introduced into the wood veneer (12) by embossing, Before the indentations are made, the wood veneer (12) is coated with a release coating (14) for removing the metal paste (22) from the wood veneer (12), wherein the release coating (14) is breached in the area of ​​the indentations (16) when the indentations (16) are made, at least the indentations (16) are completely filled with the metal paste (22), the metal paste provided in the recesses (16) is hardened, excess metal paste (22) located outside the recesses (16) is removed, the separating coating (14) in an intermediate area (18) provided between the recesses (16) is completely or partially removed when the excess metal paste (22) is removed and the wood veneer (12) is joined to a three-dimensionally shaped rigid support part (20) after the indentations (16) have been made and before the indentations (16) have been filled with metal paste (22).

Description

[0001] The invention relates to a method for manufacturing such a decorative part, with the aid of which an interior trim of a motor vehicle can be executed.

[0002] From DE 197 54 420 C1 it is known to emboss a wood veneer for the optical appearance of a decorative part of an interior trim of a motor vehicle and to fill the embossed and partially colored indentations with a clear lacquer.

[0003] From DE 10 2009 054 488 A1 it is known to introduce an artificial grain into a base body consisting of a fibrous material with wood by discoloring in areas opened by means of a color and / or coating material containing a metal particle.

[0004] From DE 10 2006 056 272 A1 it is known to fill openings in a body made of wood with a filling material that is at least partially transparent.

[0005] From EP 2 927 016 A1 it is known to fill depressions in the top surface of a floor panel by 3D printing with a metal filler material.

[0006] If a decorative part of an interior trim of a motor vehicle is to be provided with a metallic look, it is known to create a recess corresponding to the metallic look in a wood veneer and to insert a prefabricated metal strip or metal matrix corresponding to the shape of the recess into this recess.

[0007] There is a constant need to be able to equip a decorative part for the interior trim of a motor vehicle with a particularly fine metallic look.

[0008] The object of the invention is to enable a decorative part for the interior trim of a motor vehicle with a particularly fine metallic look.

[0009] The problem is solved according to the invention by a method having the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims and the following description, each of which can individually or in combination represent an aspect of the invention.

[0010] According to the invention, a method for manufacturing a decorative part for the interior trim of a motor vehicle is provided, wherein the decorative part comprises a wood veneer, the wood veneer having indentations, the indentations being filled with a hardened metal paste, the hardened metal paste being provided exclusively in the indentations, the indentations being created in the wood veneer by embossing, the wood veneer being coated with a release agent for removing the metal paste from the wood veneer before the indentations are created, the release agent being breached in the area of ​​the indentations during the creation of the indentations, at least the indentations being completely filled with the metal paste, the metal paste provided in the indentations being hardened, and excess metal paste located outside the indentations being removed.The separating coating in an intermediate area provided between the recesses is completely or partially removed when the excess metal paste is removed, and the wood veneer is bonded to a three-dimensionally shaped rigid carrier part after the recesses have been created and before the recesses have been filled with metal paste.

[0011] Due to its pasty consistency, the metal paste can be easily applied to the recesses and adapted to their contours. Unlike inserting metal strips or prefabricated metal parts into the recesses, the metal paste automatically fills and compensates for any gap that would otherwise form between the metal material and the wood veneer. Manufacturing tolerances can be automatically compensated for by the metal paste. The metal paste can be applied, for example, by spraying and / or troweling, thus filling the recesses. Excess metal paste can then be wiped away, leaving only the recesses where it can harden. Areas of the wood veneer outside the recesses remain essentially free of metal paste.Alternatively, the metal paste can first harden and then be removed from the interstitial areas, for example, by machining. This results in very high dimensional accuracy and edge sharpness of the metallic material embedded in the wood veneer, which would not be possible when using a metal inlay of this quality. In particular, even very complex and especially fine metallic areas can be created within the wood veneer, so that small-scale metallic ornaments can easily be incorporated into the decorative element. Because the metal paste can be easily adapted to the potentially very complex and / or fine design of the recesses, a decorative element for the interior trim of a motor vehicle with a particularly fine metallic appearance can be produced.

[0012] The metal paste can be removed while still in a pasty state, for example by wiping and / or scraping off the excess. Alternatively, the metal paste can be allowed to harden first and then removed, particularly by machining, thus avoiding potential impairment of the decorative part's surface quality due to shrinkage effects of the metal paste during hardening. The sequence of the process steps for removing and hardening the metal paste can therefore vary depending on the application.

[0013] Embossing allows for the creation of particularly fine and complex structures in the form of indentations in wood veneer. Simultaneously, the pressure generated during embossing can be used to compress the veneer. For this purpose, a flat counter plate can be used, which can engage the underside of the veneer facing away from the indentations to be created. Specifically, the indentations are created during embossing using an embossing roller and / or an embossing die, whereby the wood veneer is compressed to a reduced thickness during the process. The embossing roller and / or die can have a positive shape for the indentations to be created, which can be produced with very high precision, for example, by milling, electrical discharge machining (EDM), and / or laser shaping.

[0014] The release agent can be damaged by the creation of the depressions to such an extent that the metal paste can easily penetrate the depressions and, in particular, bond with the sides of the depression not coated with the release agent. The release agent remains intact in the area between the depressions, allowing the metal paste to be easily removed from this area. If at least part of the release agent is also removed when the metal paste is removed, it can be ensured that the metal paste can be removed from the area essentially without leaving any residue. In particular, if part of the release agent is to remain, for example, to protect the surface of the wood veneer and / or to color the appearance of the wood veneer, a sufficiently large layer thickness can be provided for the release agent.

[0015] The wood veneer can be cut to the desired three-dimensional shape before being attached to the substrate. This is particularly important when the wood veneer is applied to the outer surface of a curved area of ​​the substrate, as the indentations may flex slightly, increasing the capacity for the metal paste. Since the metal paste is applied only after the wood veneer has been curved, it prevents the paste from being squeezed out of the indentation or chipping off its edge. This ensures a smooth surface finish for the decorative element.

[0016] For example, the line width b of the metal paste cured in the recesses can be b ≤ 1.0 mm, in particular b ≤ 0.8 mm, preferably b ≤ 0.5 mm, and most preferably b ≤ 0.3 mm, with b ≥ 0.25 mm being more preferred so that the metallic area in the decorative part remains clearly visible. The metal paste can, for example, be a suspension of a preferably pasty binder loaded with metal powder and / or metal flakes. In particular, the suspension can contain a plasticizer that can evaporate, for example, upon application of heat. The binder and / or the plasticizer are, in particular, substantially transparent, so that the appearance of the metal paste is essentially determined by the metal in the metal paste. When a sufficient proportion of the plasticizer has evaporated from the metal paste, the binder can harden and transition from a more pasty state to a more solid state.Suitable metal pastes are known, for example, from applications for the production of fine conductor tracks in microchips, as described, for example, in EP 2 638 991 A1.

[0017] In particular, the hardened metal paste is designed to be flush with the surface of the wood veneer, forming an intermediate area between the recesses. This results in an essentially flat surface for the decorative element, which can lead to a high-quality tactile appearance. Specifically, steps, gaps, and / or joints at the interface between the metal paste and the wood veneer can be avoided.

[0018] Preferably, the wood veneer has a release coating in an intermediate area provided between the recesses for the removal of metal paste from the wood veneer. The release coating allows for easy removal of the metal paste from the surface of the wood veneer formed by the release coating, without unintentionally damaging the surface of the wood veneer. In particular, the metal paste is insoluble in the release coating. Furthermore, the release coating prevents the metal paste from penetrating the pores of the wood veneer and thus prevents it from being completely or at least only with difficulty removed from the intermediate area. Preferably, the pores of the wood veneer in the intermediate area are filled by the release coating. The release coating can contain a dye, making it possible to adjust the color of the wood veneer.Preferably, the separating coating is essentially transparent, allowing the natural color of the wood veneer to show through. The separating coating is, for example, made of a lacquer.

[0019] Densified wood veneer is particularly preferred. Its density can be greater than that of naturally occurring veneer because the thickness of the material has been reduced in a densification step. This reduces voids and pores in the veneer, resulting in increased stability. The indentations are created by embossing, a process that simultaneously densifies the veneer.

[0020] In particular, the wood veneer is bonded to a three-dimensionally shaped, rigid substrate. The wood veneer can, for example, be glued to the substrate. The substrate can be designed to withstand forces occurring during operation. The substrate can be laminated on one side with the wood veneer. By bonding the relatively flexible wood veneer to the substrate, a three-dimensional design of the wood veneer can be fixed, and the shape of the decorative element can be defined.

[0021] After the metal paste has been removed, the surface of the decorative element can be treated, at least locally, preferably across its entire surface, and in particular polished. This allows the gloss of the hardened metal paste in the recesses and / or the wood veneer in the interstitial areas to be adjusted as desired. The decorative element can, in particular, have a protective layer, such as a clear lacquer, forming the outer surface of the decorative element. This protective layer can shield the wood decor, the hardened metal paste, and, if applicable, the release agent from external influences, such as impacts and / or moisture.

[0022] The invention is explained below by way of example with reference to the accompanying drawings and preferred embodiments, wherein the features shown below can represent an aspect of the invention, either individually or in combination. The drawings show: Fig. 1 a schematic sectional view of a decorative part at an initial point in time of manufacture, Fig. 2 a schematic sectional view of the decorative part made of Fig. 1 at a later second production time, Fig. 3 a schematic sectional view of the decorative part made of Fig. 2 at a later third production date, Fig. 4 a schematic sectional view of the decorative part made of Fig. 3 to a later fourth production time and Fig. 5 a schematic sectional view of the decorative part made of Fig. 4 at a later fifth production time.

[0023] The in Fig. The decorative element 10 shown in the illustration is initially a wood veneer 12, which is coated on its visible surface in the installed state with a colored or transparent separating coating 14. In the Fig. In the manufacturing step shown in Figure 1, the wood veneer 12 is exposed to an embossing roller, which creates indentations 16 into the wood veneer 12 from the top side and simultaneously compresses the wood veneer 12. The embossing roller can dig into the wood veneer 12, which is coated with the release agent 14, to such an extent that the release agent 14 is breached in the area of ​​the indentations 16. The release agent 14 remains intact in the intermediate areas 18 between the indentations 16.

[0024] The decorative part 10 obtained after this manufacturing step can then be suitably cut and three-dimensionally shaped. For this purpose, the wood veneer 12 can be joined to a three-dimensionally shaped carrier part 20, as shown in Fig. 2 shown. The three-dimensional shaping of the decorative part 10 can change the receiving volume of the recesses 16 provided in the curved wood veneer 12.

[0025] Subsequently, a metal paste 22 can be applied to the decorative part 10, as shown in Fig. Figure 3 shows that the metal paste 22 can completely fill the recesses 16. Preferably, the thickness of the metal paste layer is such that not only are the recesses 16 completely filled, but the intermediate areas 18 are also covered.

[0026] For example, the metal paste 22 can then harden. As in Fig. As shown in Figure 4, the metal paste 22 can, for example, be partially removed by machining. In particular, the metal paste 22 can be removed down to a layer thickness at which the separating coating 14 in the intermediate areas 18 is completely or partially removed. In particular, the gloss level of the metal paste remaining in the recesses 16 and / or the intermediate areas 18 can be adjusted, for example, by a polishing step.

[0027] As in Fig.As shown in Figure 5, the decorative part 10 can be provided on its upper surface with a protective layer 24, particularly a clear lacquer, which is especially transparent. Preferably, a substrate body 26 is provided on an underside of the carrier part 20. This substrate body is made of a plastic, for example PUR, and gives the decorative part 10 a desired defined shape, which facilitates its installation in the interior trim of a motor vehicle. Preferably, the carrier part 20 is completely enclosed by the wood veneer 12 and the substrate body 26.

Claims

[1] Method for manufacturing a decorative part (10) for an interior trim of a motor vehicle, where the decorative part (10) a wood veneer (12) wherein the wood veneer (12) has depressions (16), wherein the depressions (16) are filled with a hardened metal paste (22), wherein the hardened metal paste (22) is provided exclusively in the recesses (16), in which the indentations (16) are introduced into the wood veneer (12) by embossing, Before the indentations are made, the wood veneer (12) is coated with a release coating (14) for removing the metal paste (22) from the wood veneer (12), wherein the release coating (14) is breached in the area of ​​the indentations (16) when the indentations (16) are made, at least the indentations (16) are completely filled with the metal paste (22), the metal paste provided in the recesses (16) is hardened, excess metal paste (22) located outside the recesses (16) is removed, the separating coating (14) in an intermediate area (18) provided between the recesses (16) is completely or partially removed when the excess metal paste (22) is removed and the wood veneer (12) is joined to a three-dimensionally shaped rigid support part (20) after the indentations (16) have been made and before the indentations (16) have been filled with metal paste (22). [2] Method according to claim 1 characterized by , that the hardened metal paste (22) is flush with the surface with an intermediate area (18) of the wood veneer (12) provided between the recesses (16). [3] Method according to claim 1 or 2 characterized by, that the wood veneer (12) has a separating coating (14) in an intermediate area (18) provided between the recesses (16) for removing metal paste (22) from the wood veneer (12). [4] Method according to any one of claims 1 to 3 characterized by , that the wood veneer (12) is compressed. [5] Method according to any one of claims 1 to 4 characterized by , that the wood veneer (12) is connected to a three-dimensionally shaped rigid support part (20). [6] Method according to any one of claims 1 to 5, wherein the excess metal paste (22) located outside the recesses (16) is removed by machining. [7] Method according to any one of claims 1 to 6, wherein the depressions (16) are introduced during embossing using an embossing roller and / or an embossing die. [8] Method according to any one of claims 1 to 7, wherein the wood veneer (12) is compressed to a lower material thickness during embossing. [9] Method according to any one of claims 1 to 8, wherein the metal paste (22) is a suspension comprising a binder loaded with metal powder and / or metal flakes and a plasticizer evaporable by heat input.

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