DE10356944A1 - Coating process for coating a substrate with metal - Google Patents

Abstract

The invention relates to a coating method for coating a non-metallic or metallic surface of a substrate. In order to adapt the haptic and physical properties of the surface of the article to that of a metallic article, the invention proposes to deposit DOLLAR A a metal of high thermal conductivity on an adherent substrate of the substrate as a base layer to a thickness such that the coated substrate in the haptic Substrate corresponds to metal, and then deposit a metallic decorative layer on the base layer and apply a transparent protective layer on the decorative layer.

Description

The The invention relates to a coating method for coating a non-metallic or metallic substrate with metal.

nowadays Become high-quality commodities such as furnishings, interiors of automobiles, electronic devices and their accessories like buttons, Switches and other decorative items, where there is a representative look and / or a high utility value, made of solid metal or made of metal-encased plastic, glass or ceramic. Such commodities, which can have complex and filigree structures can only be economically viable manufactured as molded parts, extruded parts or similar technique. By applying layers of paint or plastic layers on the surfaces such objects results in a poor overall impression, especially at later touch. Also worsen Grease stains and scratches the overall impression of the objects.

outgoing of these disadvantages, the invention is based on the object a coating of objects to disposal to provide with their help the properties of solid metal parts can be reproduced.

to solution this derived from the prior art and previously indicated Task proposes the invention, a method for the entire partial coating by depositing a metal of high thermal conductivity on an adherent Substrate of the substrate as a base layer in such a thickness, that the coated substrate in the haptic of a substrate Metal corresponds, by subsequent deposition of a metallic Decorative layer on the base layer and finally applying a transparent protective layer on the decorative layer.

The inventive production the surface structure of the object leads to a substantially compact, monolithic overall impression of the object, in the essential physical properties like heat conduction, heat capacity, electrical Conductivity, Roughness may correspond to those of a metallic object.

The Deposited base layer may be formed of metal or metal oxides be, even on rough surfaces a good conductivity exhibit. The amount of deposited metal on the substrate must be chosen like this be that the coated substrate in the haptic a substrate made of metal. This is due to a sufficient layer thickness reached. The thicker the layer, the sooner the impression is created a fully metallic object. The haptic impression of a full metallic object is already from a certain layer thickness reached. The application of further metal as a base layer improved then the sensation only slightly.

On the base layer can subsequently a metallic decorative layer can be applied. The example made of titanium, anodically modified titanium, tantalum or aluminum is. The final one Applying a transparent protective layer can increase the Scratch resistance or serve as fingerprint protection.

It It is suggested that the adherent substrate of the substrate by deposition of metal or metal oxide vapor under vacuum (PVD) is produced. The plasma-assisted deposition allows a to the surface the substrate adapted to apply the metal layer to a firm To ensure connection. Here you can Plasma parameters such as energy of the ions, the density of neutral particles or ionization degree. It is also suggested that the metal or metal oxide vapor deposition takes place plasma-assisted.

Around to ensure an adherent surface and also the Depositing other metallic layers to simplify is also suggested that for the adherent substrate a good conductive material, such as Chromium, nickel, titanium, copper etc. is used. This metallic Layer is particularly suitable for the application of another metallic layer, through a galvano process.

to warranty an adherent surface which withstands also mechanical stress and a leaves a good haptic impression, it is suggested that the substrate is produced in a thickness of 20 to 15,000 nm. Particularly advantageous is a layer thickness of 50 to 5000 nm.

A Good connection between underground and base layer is thereby allows that for the Base layer a metal with good thermal and / or electrical conductivity is used. In this case, in particular copper or nickel can be used. These metals can be, for example, with a galvano process or wet-chemically.

The fact that the base layer is electrically conductive both electrically and thermally, it improves the haptic impression. The good thermal conductivity gives the user the impression of a full metal, as the body temperature is well forwarded from the pressure point. The applied base layer also serves to strengthen the layer, increases the mechanical strength and improves the current carrying capacity of the article. In addition, a surface structure that corresponds to that of a solid metal.

The Base layer can be used to improve the surface structure and to achieve be subjected to surface treatment for decorative purposes. For this purpose, blasting, pickling, polishing, grinding, electropolishing, Shape and structuring in an advantageous manner.

For applying The base layer is preferably applied by electroplating or wet-chemically becomes. This allows a uniform material application also guaranteed on complex objects become.

The Base layer preferably has a thickness of 1 to 1,000 μm. Preferably are 5 to 200 microns intended. These layer thicknesses guarantee on the one hand a metallic haptic overall impression and allow on the other hand, the cost-effective Making the coating.

It will also proposed that on the base layer a wear protection layer is applied, their hardness many times higher is, as that of the base layer. Such a wear protection layer elevated the overall strength of the layer structure. The wear protection layer can be plasma enhanced be applied.

Therefore It is suggested that the application of the wear protection layer by plasma-assisted Vapor deposition of the wear protection material he follows.

in this connection For example, the wear protection layer with a reactive cathodic arc are applied. The wear protection layer may be a hard material layer.

Around to improve the adhesion of further layers to the base layer, It is suggested that the base layer before depositing a another layer to its surface is treated mechanically or chemically.

Around the aesthetic Overall impression of the substrate, it is proposed an additional Apply decorative layer. This decorative layer can be made of titanium, anodic modified titanium, tantalum, aluminum, etc. may be formed. Especially is advantageous if the metallic decorative layer anodized or anodized.

Around to increase the scratch resistance and fingerprint protection it is also proposed that a transparent protective layer is applied. This is preferred that the transparent protective layer in the form of a powder coating, Electrocoating or electrostatic spray painting is applied. The coating is preferably using a sol-gel process for the production of inorganic-organic hybrid polymers applied (sol-gel technology). However, it is also a conventional one Scratch-resistant paint possible.

The preferred thickness of such a protective layer is between 0.2 and 5 μm in the sol-gel process. In the painting this lies between 5 and 50 μm. In the case of titanium, fingerprint protection and a scratch and corrosion protection necessary.

Around the substrate, for example, with different surfaces It is suggested that the multilayer coating be considered removable shell or cap made on the substrate or that Substrate dissolved becomes. In this case, the layer structure can be removed or the substrate removed or resolved become.

Finally will preferred that the substrate coated with a release agent prior to coating becomes. This makes it possible to separate the substrate more easily from the layer structure.

The The invention will be explained in more detail with reference to a drawing showing an embodiment.

In the drawing shows:

1 the course of the method according to the invention;

2 a layer structure according to the invention.

In the method according to the invention, it is assumed that a metallic or non-metallic commodity article, which often has a coating of a non-metallic surface. Such articles made of plastic, glass, ceramic or metal can often have a complex structure that can be produced economically only by injection molding or extrusion. When applying color layers or plastic layers to the surfaces, the articles then have an inferior optical Impression on.

In order to improve the visual impression of such objects and to be able to adapt the properties to that of a fully metallic object, as in 1 shown, suggested that a substrate in a first step 1 is coated with an adherent substrate. The substrate can be applied by deposition of metal or metal oxide vapor in a vacuum. Also, metal reaction products can be deposited as a substrate. Depending on the material of the substrate itself and the material with which the object is recoated, the parameters of the vapor deposition can be adjusted. Here, the ion energy, the plasma temperature, the degree of ionization and the density of the neutral particles can be adjusted. The setting serves to create an adherent substrate on the substrate on which a base layer can then be adhered. The substrate can be formed from metal or metal oxides or their reaction products. For example, chromium, nickel, titanium, copper, etc. are suitable in each case elementally or as a layer combination or alloy. These metals have good conductivity even on rough surfaces. Preferred is a layer thickness of about 5.0nm - 5.000nm.

At the second step 2 is then applied in a galvano process copper, nickel, zinc, silver, gold or their alloys or in combination sequence with a layer thickness between 1 and 1000 microns. The galvanization serves to strengthen the layer. Furthermore, the base layer serves to improve the visual impression, the mechanical strength, the surface structure and the current carrying capacity as well as other properties of the object. With the aid of the galvanized base layer, the article now has the properties of an article which is formed of solid metal.

In order to achieve the desired final structure of the surface, in the next step 3 a surface treatment of the object carried out. For this purpose, for example, blasting, pickling, polishing or structuring is proposed.

The thus surface-treated article becomes the following step 4 covered with a wear protection layer. This may be a hard material layer, which is applied plasma-assisted. For the job, a reactive cathodic arc is suitable. The hard material layer increases the overall strength of the layer structure.

In the subsequent step 5 Another decorative layer can be applied. This can serve to give the object a certain metallic effect. As a decorative layer, for example, titanium, anodically modified titanium to achieve a color effect, tantalum or aluminum is suitable.

Finally, in the last step 6 applied a transparent protective layer. This transparent protective layer serves to increase the scratch resistance of the article. Furthermore, the protective layer can ensure fingerprint protection.

After that is the surface of the article treated so that the object both a optically high-quality impression leaves, as well as physical Has properties of a solid metal formed article. The load capacity, the surface structure, the current carrying capacity and the haptic properties are similar to those of metal formed object.

2 shows a layer structure according to the invention. Shown is a substrate 10 which may be a plastic, for example. On this substrate becomes a substrate 11 applied. The subsurface may be a vapor of a metal, a metal oxide or other metal reaction product or combination sequences and deposited with plasma assistance. For the underground 11 In particular, layer thicknesses between 20 and 15,000 nm are suitable.

On the ground 11 becomes a base layer 12 applied, which is formed of metal with good thermal and / or electrical conductivity. Particular mention should be made here of copper, zinc, nickel, gold, silver or their alloys and reaction products. Layer sequences in any combination of the aforementioned metals can also be applied as the base layer. For the base layer 12 a layer thickness between 1 and 1000 microns is preferred.

The base layer 12 Can be first surface treated to achieve a special overall aesthetic impression. Here, the base layer 12 be treated by blasting, pickling, polishing, electropolishing, embossing, grinding, structuring or chemical processes.

After the base layer 12 deposited and treated, a decorative layer can be evaporated. The decorative layer may be, for example, titanium, anodically modified titanium, tantalum, aluminum, copper, gold, silver or other metal. The decorative layer can be changed by anodizing or anodizing and so change the visual impression of the substrate. By oxidation, for example, the color of the decorative layer can be changed.

On the decorative layer 13 can be a wear protection layer 14 be applied. The wear protection layer 14 can be vapor-deposited or applied by a galvano process. It is preferably thin and thermally conductive.

Finally, on the substrate 10 a protective layer 15 be applied. The protective layer 15 serves as scratch protection or fingerprint protection. In this case, it may be transparent and applied in the form of a powder coating, an electrodeposition coating or an electrostatic spray coating. The protective layer 15 can also be non-metallic.

The layer system of underground 11 , Base layer 12 , Decorative layer 13 , Wear protection layer 14 and protective layer 15 make it possible for the substrate 10 to give a haptic overall impression of a solid metal.

Claims (16)

Process for total or partial coating a non-metallic or metallic substrate with metal by depositing a metal of high thermal conductivity on an adherent substrate of the substrate as a base layer in such a thickness that the coated substrate in the haptic corresponds to a metal substrate, by subsequent Depositing a metallic decorative layer on the base layer and final application a transparent protective layer on the decorative layer. Method according to claim 1, characterized in that that the adherent substrate of the substrate by deposition of Metal or metal oxide vapor under vacuum (PVD) is produced. Method according to claim 2, characterized in that that the metal or metal oxide vapor deposition takes place plasma-assisted. Method according to one of claims 1 to 3, characterized that as material for the adherent substrate a good conductive material, in particular Chrome, nickel, titanium, copper is used. Method according to claim 4, characterized in that that the substrate in a thickness of 20 to 15000 nm, in particular 50 to 5000 nm, is produced. Method according to one of claims 1 to 5, characterized that for the base layer is a metal with good thermal and / or electrical conductivity, in particular copper, is used. Method according to Claim 6, characterized that the metal for the base layer is applied galvanically or wet-chemically. Method according to claim 6 or 7, characterized that the base layer in a thickness of 1 to 1000 microns, in particular 5 to 200 μm is applied. Method according to one of claims 1 to 8, characterized that a wear protection layer is applied to the base layer is whose hardness many times higher is as the base layer. Method according to one of claims 1 to 4, characterized that the application of the wear protection layer by plasma-assisted vapor deposition the wear protection material takes place. Method according to one of claims 1 to 4, characterized that the base layer before depositing another layer on their surface is treated mechanically or chemically. Method according to one of claims 1 to 11, characterized that for the decorative layer titanium, tantalum or aluminum is used. Method according to one of claims 1 to 12, characterized that a metallic decorative layer is anodized or anodized. Method according to one of claims 1 to 5, characterized that the transparent protective layer in the form of a powder coating, electrocoating or electrostatic spray painting he follows. Method according to one of claims 1 to 14, characterized that the multilayer coating acts as a removable shell or cap the substrate is prepared or the substrate is dissolved. Method according to one of the claims 15, characterized in that the substrate is coated with a release agent prior to coating becomes.