DE10303650A1 - Coating of objects such as plastic sprays comprises application of a layer of copper, nickel or a copper-nickel alloy, mechanical surface treatment of at least the outer applied layer and application of a palladium-nickel layer - Google Patents

Abstract

A process for the coating of objects (I), preferably of sanitary articles such as sprays comprising plastic or having plastic surfaces comprises application of at least one layer of copper, nickel or a copper-nickel alloy, mechanical surface treatment of at least the outer applied layer and application of at least one palladium-nickel layer. An Independent claim is included for the resulting coated object (I).

Description

The invention relates to a method for coating objects, especially of sanitary items like Sanitary showerheads, which consist of plastic or have plastic surfaces, and the objects that can be produced using this method.

The most varied have been around for a long time objects for a variety of reasons coated with inorganic or organic substances. Reason for this Coatings are on the one hand functional requirements, e.g. B. corrosion protection, or other decorative requirements, z. B. the visual appearance. Often objects are both coated for functional as well as decorative reasons.

Coatings are of particular importance for all types of sanitary items, in particular for sanitary fittings or sanitary showers. These have to namely on the one hand meet functional requirements, d. H. be highly corrosion resistant, be easy to clean, scratch resistant to just a few of these To name requirements. Second, they have high decorative claims sufficient d. H. to have to for example shiny or matt surfaces be provided with certain "optics". To meet these requirements, are a wide variety of metals as coating materials used that frequently applied to the corresponding base body by galvanic deposition become. A well-known example is the application of chrome, being shiny surfaces high corrosion resistance be preserved.

The in the coating of objects, in particular in sanitary engineering, Problems arise with objects made of plastic or with Plastic surfaces in particular. In contrast to metals, plastics have a very low level Heat capacity. Therefore is a mechanical surface treatment from metallized plastic parts only possible to a limited extent, otherwise the heat input resulting from the mechanical treatment into the plastic part the (especially electroplated) Can remove metal layers from the plastic surfaces again. This can lead to high reject rates lead in industrial production. In addition, at coated plastic objects certain "optics" are difficult to adjust. This is particularly true for the so-called "stainless steel look". With such a execution the metal-coated plastic part should give the visual impression a stainless steel surface, especially a brushed one stainless steel surface exhibit. Sanitary fittings, sanitary showers or at least the parts belonging to such fittings, such as connecting parts, Rosettes or connecting parts are often made of plastic and subsequently (with metals) coated. Such coated plastic parts should then have the same visual appearance as stainless steel manufactured items have.

To provide surfaces of certain Optics on plastic objects there are already various approaches in the prior art. So will the desired surface frequently imitated by a painting process. The paint contains, for example Aluminum pigments, which by adding dyes accordingly colored become. The surfaces obtained are optical Appearance and functional properties such as scratch resistance often unsatisfactory.

With a different approach a copper layer applied to the plastic part is brushed and subsequently nickel-plated. This nickel layer is then covered with a transparent protective lacquer Mistake. The disadvantage of this method is that damage corrosion protection is also lost in the paint layer.

As an alternative to the above Painting process can also on matt chrome-plated plastic parts in the Vacuum (PVD process) stainless steel or a stainless steel-like Layer can be applied. The resulting surface has then the color of stainless steel, but not the typical surface structure of brushed Stainless steel. Another disadvantage is that the application of metal layers is very expensive in the PVD process.

The invention therefore arises u. a. the task, the above-mentioned disadvantages of the prior art to avoid. In particular, a coating method for objects that consist of plastic or have plastic surfaces provided be targeted at a specific visual appearance of the coated article can be reached. In particular is intended with the invention a method for providing a coated Item with the visual appearance of brushed Stainless steel. The coated object should with this optic the functional requirements placed on it, especially in sanitary engineering, fulfill.

This task is solved by the method with the features of claim 1 and by the subject with the features of claim 9. Preferred embodiments this method and this object are in dependent claims 2 to 8 and 10 to 25. The wording of all claims will hereby incorporated by reference into the content of this description.

The method mentioned at the beginning stands out according to the invention from that on the object has at least one layer of copper, nickel or one Copper-nickel alloy is applied and at least the same the uppermost layer obtained is mechanically surface-treated. Then over the surface treated layer applied at least one palladium-nickel layer.

The above surface treatment is done preferably by brushing and / or rays. It is further preferred if the surface treatment in any case done at least partially by brushing. Polishing too is the preferred surface treatment to call.

A mechanical surface treatment is intended here under brushes be understood in which the surface with a brush or an equally effective machining means of sufficient strength and Hardness under partial removal of the metal layer is processed. Through this Process will surface the characteristic structures such as grooves, depressions and the like incorporated as they are for such a processing with brushes known to the person skilled in the art is characteristic are. The brushed metal layer in question is of course not Completely ablated.

The skilled person understands radiation As is well known, a mechanical surface treatment, for example (Quartz) sand or glass beads as blasting media (diameter usually 0.5 to 1.5 mm) with the help of compressed air blowers hurled onto the corresponding surface become. This creates the for the blasting characteristic surface structures.

As already mentioned, the invention can to brush and the blasting can be used alternatively or in combination. At least part of the surface to be treated is preferably brushed, wherein then in particular the parts of the surface with the brush / brush disc can only be reached and processed with difficulty.

The layers of copper, nickel or copper-nickel alloys are preferred according to the invention comparatively "soft" trained so a simple mechanical surface treatment, especially by brushing, is made possible. Copper layers, in particular galvanically deposited copper layers, are usually sufficient soft. In this context, the so-called to emphasize (known to the person skilled in the art) sulfamate nickel as preferred, which consists of a nickel bath based on sulfamate (without organic additives) soft matt nickel is deposited.

The method according to the invention is preferred designed so that on the subject first a copper layer and then a nickel layer is applied. This nickel layer is then mechanically surface-treated, preferably brushed and / or blasted.

The nickel layers are according to the invention in particular so-called sulfamate nickel layers, d. H. soft matt nickel layers, as they are known to the expert.

After the invention, it is further preferred if on the surface treated Layer before applying the palladium-nickel layer at least one another layer of copper, nickel or a copper-nickel alloy is applied. Such additional layers can, depending on the metal used, the corrosion resistance increase or special optical effects in the finally obtained coated Evoke object. It is preferably the other Layer around a nickel layer, in particular around a so-called sulfamate nickel layer.

As from the previous statements the layers of the above are already partially apparent Metals preferably at least according to the invention partly by electrodeposition, d. H. by deposition obtained from an electrolyte under current flow. Preferably all galvanically deposited on the object applied metal layers. The plastic object, which is not conductive per se, is replaced by the Methods known to those skilled in the art. made conductive. For example, the plastic surface Electrolessly activated with palladium and electrolessly metallized with nickel. On the thin one thus obtained If necessary, the nickel layer can be deposited by current deposition Pre-nickel layer can be applied. The basic structure thus obtained is then further treated according to the invention.

In a further development it is with the method according to the invention preferred if over the (possibly top) palladium-nickel layer at least a siloxane or polysiloxane top layer is applied. Siloxanes / polysiloxanes are known to be obtained from organosilanes, for example by thermal Treatment. The so-called sol-gel process is particularly suitable for this purpose, that to the polysiloxane layers also known in the literature under the keyword “sol-gel coatings” leads. A such cover layer causes an additional sealing of the surface and their physical and chemical properties (e.g. in relation to on abrasion resistance, Corrosion resistance, Water repellent effect for liquids and the like) improve. Although appropriately pigmented Polysiloxane layers are possible according to the invention, it will As a rule, the top layer around a transparent polysiloxane layer act.

It is understood that the object to be coated can be subjected to a conventional pretreatment before the method according to the invention is carried out. Such pretreatment steps are known to the person skilled in the art. In addition to making the object conductive, here are the usual che mix and / or name physical methods that can be cited under the keywords anodic degreasing, cathodic degreasing, hot degreasing, ultrasonic degreasing and the like. Such known pretreatment and activation steps can of course also be used between the individual process steps, for example before the application of further metal layers.

The subject matter of the invention, i. H. preferably the sanitary object according to the invention like a sanitary shower according to the invention consists of a body made of plastic or a basic body with plastic surfaces. On this basic body there is at least one layer of copper, nickel or one Copper-nickel alloy, the top layer being mechanically surface-treated is. about this top (surface treated) Layer is then at least one palladium-nickel layer.

The top layer on top of that the palladium-nickel layer is in particular brushed and / or blasted. In terms of the surface structures defined with it becomes explicit on the above statements Referenced and referred.

In training is at the subject of the invention preferably at least one further layer of copper, nickel or a copper-nickel alloy between the surface-treated Layer and the palladium-nickel layer.

• 1. Gegenstand mit – einem Grundkörper aus Kunststoff oder einem Grundkörper mit Kunststoffoberflächen, – einer sich auf dem Grundkörper befindenden Schicht aus Kupfer oder Nickel, wobei – diese Kupferschicht oder Nickelschicht mechanisch oberflächenbehandelt, vorzugsweise gebürstet ist, und – einer Palladium-Nickel-Schicht auf der oberflächenbehandelten Kupferschicht oder Nickelschicht.
• 2. Gegenstand mit – einem Grundkörper aus Kunststoff oder einem Grundkörper mit Kunststoffoberflächen, – einer sich auf dem Grundkörper befindenden Kupferschicht, – einer sich auf der Kupferschicht befindenden Nickelschicht, wobei – diese Nickelschicht mechanisch oberflächenbehandelt, vorzugsweise gebürstet ist, und – einer Palladium-Nickel-Schicht auf der oberflächenbehandelten Nickelschicht.

In accordance with the previous statements, preferred objects according to the invention can accordingly be characterized by the following structure:

• 1. Object with - a base made of plastic or a base with plastic surfaces, - a layer of copper or nickel located on the base, wherein - this copper layer or nickel layer is mechanically surface-treated, preferably brushed, and - a palladium-nickel layer the surface-treated copper layer or nickel layer.
• 2. Object with - a base made of plastic or a base with plastic surfaces, - a copper layer on the base, - a nickel layer on the copper layer, - this nickel layer being mechanically surface-treated, preferably brushed, and - a palladium-nickel -Layer on the surface-treated nickel layer.

With the object defined under 2. can between the surface treated Nickel layer and the palladium-nickel layer preferably one there is another nickel layer.

For all defined under 1. and 2. objects it can be surface-treated Nickel layer preferably around a so-called sulfamate nickel layer act. Such nickel layers are known to the person skilled in the art as a soft matt Nickel layers known. The copper layers mentioned under 1. and 2. are preferably matt copper layers.

Are further layers of nickel (between surface treated Layer and palladium-nickel layer), so it is preferably also so-called sulfamate nickel layers.

In all embodiments according to the invention of the subject invention can get over the (possibly top) palladium-nickel layer (at least) a siloxane / polysiloxane cover layer.

• – ein Grundkörper aus Kunststoff oder ein Grundkörper mit Kunststoffoberflächen,
• – einer sich auf dem Grundkörper befindenden Kupferschicht,
• – einer sich auf der Kupferschicht befindenden Nickelschicht, vor zugsweise Sulfamatnickelschicht, die mechanisch oberflächenbe handelt, vorzugsweise gebürstet ist,
• – einer sich auf der oberflächenbehandelten Nickelschicht befinden den weiteren Nickelschicht, vorzugsweise Sulfamatnickelschicht,
• – einer sich auf dieser weiteren Nickelschicht befindenden Palladium-Nickel-Schicht, und
• – einer sich auf der Palladium-Nickel-Schicht befindenden Polysiloxan-Deckschicht.

Accordingly, a particularly preferred object according to the invention is defined by the following structure:

• A base body made of plastic or a base body with plastic surfaces,
• A copper layer located on the base body,
• A nickel layer located on the copper layer, preferably a sulfamate nickel layer, which is mechanically surface-treated, preferably brushed,
• A further nickel layer, preferably sulfamate nickel layer, is located on the surface-treated nickel layer,
• - A palladium-nickel layer located on this further nickel layer, and
• - A polysiloxane top layer located on the palladium-nickel layer.

Basically, the invention Palladium-nickel layers of any alloy composition usable. Preferably is the palladium content, however, is at least 50 atomic percent, in particular at least 70 atomic percent. Palladium is more preferred of about 80 atomic percent. Because of the high palladium content the layers obtained have particularly good corrosion resistance, the even higher than can be with stainless steel.

In principle, the layer thicknesses of the coatings applied to the object are not critical. However, in order to be able to perform their function particularly well, there are preferred ranges for these corresponding layer thicknesses. The layer thickness of the first metal layer on the object, that is to say in particular the copper layer, is between 10 μm and 60 μm, preferably between 20 μm and 50 μm. Within this last range, layer thicknesses between further preferred 30 μm and 40 μm.

The layer thickness of the nickel layers, preferably that on a surface-treated layer is (further) nickel layers preferably between 5 μm and 25 μm, preferably between 5 μm and 15 μm. Here there are layer thicknesses within the latter range 6 μm and 10 μm in particular emphasized.

The layer thicknesses of the palladium-nickel layers) are also not critical, but are chosen to be as small as possible (e.g. less than 20 μm). Layer thicknesses between 0.1 μm and 5 μm should be emphasized. Within this The layer thicknesses range between 0.2 μm and 2 μm, in particular between 0.5 μm and 1 μm prefers.

The layer thickness of the siloxane / polysiloxane layers) is preferably less than 5 μm, in particular less than 1 μm.

According to the invention, all known and in particular usually can industrially used (galvanizable) plastics coated become. The item can either itself from the corresponding Plastic material exist or the plastic material can at least part of the surface form this item. Preferably in the invention body made of plastics as used in sanitary engineering Find use. In particular, this is the Plastic around ABS (acrylonitrile-butadiene-styrene copolymer). Also PA (polyamide) and ABS / PC (ABS copolymer with Polycarbonate) should be emphasized.

In accordance with the beginning the object of the invention preferably has the task set a so-called stainless steel look, d. H. a stainless steel-like Look for the viewer. This stainless steel look is preferably used around that of “brushed Stainless steel".

By the method according to the invention and by the subject of the invention will be a solution for the explained at the beginning Task provided. The object of the invention fulfills, in particular if it is a sanitary ware acts, both the functional as well as the decorative requirements placed on it. The object is on the one hand u. a. corrosion-resistant, abrasion-resistant, leaves liquids roll off well and has adherent surface layers. On the other hand he mediates for the buyer / user the desired Optics, in particular stainless steel optics, so that plastic objects coated in this way are optically not of objects Made of solid stainless steel or actually coated with stainless steel objects take off.

The above and other features the invention will become apparent from the description of the following For example in connection with the claims. The individual characteristics for each be realized alone or in combination with each other.

For coating a sanitary object the basic body a shower made of the plastic material ABS (acrylonitrile-butadiene-styrene copolymer) provided.

This plastic part is galvanized in the usual way with copper (layer thickness approx. 40 μm) coated. A so-called is electroplated onto this copper layer Sulphamate nickel layer (matt nickel) deposited (layer thickness approx. 10 μm). The nickel surface thus obtained will then brushed and sandblasted. For the brushing becomes a commercially available Bürstscheibe used, which is suitable, a brush structure typical of stainless steel parts with the appropriate grooves, recesses and the like. Those places of the plastic part that with the brush disc can't be edited well such as B. narrow transitions are through Machined sandblasting. After these mechanical surface treatments becomes a matt, well-textured surface received metal-coated plastic part.

On the brushed / sandblasted surface after the mechanical surface treatment a so-called sulfamate nickel layer is electroplated. This layer has a thickness of approx. 8 μm in the present case. To this The nickel layer then becomes an approximately 1 μm thick palladium-nickel layer electroplated. The palladium content of this layer is 80 Atomic percent, so excellent Corrosion properties can be achieved. The corrosion resistance is even better than that of stainless steel. The layer structure obtained is on the one hand identical in color to that of stainless steel and on the other hand the (mechanically treated) Surface structure of those of brushed Stainless steel. The plastic parts coated according to the invention are thus optical not of parts made of solid stainless steel or of stainless steel to distinguish coated plastic parts.

In a last step the metal-coated plastic part with a polysiloxane layer sealed (layer thickness approx. 0.5 μm). This final one Surface layer influenced the optical appearance and the feel of the object according to the invention Not. However, it has excellent repellency and dirt-repellent properties Properties achieved through this top layer. The polysiloxane top layer let yourself on the metal coated object due to the brushed / sandblasted surface structure it is particularly easy to apply and adheres particularly well to it metal coated object.

Claims (25)

Process for coating objects, in particular of sanitary ware like Sanitary showerheads, which consist of plastic or have plastic surfaces, in which - at least a layer of copper, nickel or a copper-nickel alloy is applied to the object - at least the top one applied Layer mechanically treated will, and - about the surface-treated Layer at least one palladium-nickel layer is applied. A method according to claim 1, characterized in that the surface treatment by brushing and / or blasting, in particular sandblasting. A method according to claim 1 or claim 2, characterized characterized that on the subject first a copper layer and then a nickel layer is applied and this nickel layer is mechanically surface-treated. Method according to one of the preceding claims, characterized characterized it the nickel layer is a so-called sulfamate nickel layer is. Method according to one of the preceding claims, characterized characterized that on the surface treated At least one layer before applying the palladium-nickel layer another layer of copper, nickel or a copper-nickel alloy is applied. A method according to claim 5, characterized in that it the other layer is preferably a nickel layer a so-called sulfamate nickel layer. Method according to one of the preceding claims, characterized characterized that the Metal layers at least partially, preferably all by galvanic Deposition can be applied. Method according to one of the preceding claims, characterized characterized in that over the palladium-nickel layer at least one siloxane and / or polysiloxane cover layer applied becomes. Object, preferably a sanitary object such as a sanitary shower, characterized in that he is structured as follows: - one body made of plastic or a basic body with plastic surfaces, - at least one on the main body layer of copper, nickel or a copper-nickel alloy, wherein at least the top layer is mechanically surface-treated is and - at least a palladium-nickel layer over this top layer. Article according to claim 9, characterized in that the top layer brushed and / or blasted, in particular sandblasted. Article according to claim 9 or claim 10, characterized by at least one further layer of copper, nickel or egg ner Copper-nickel alloy between the surface-treated layer and the palladium-nickel layer. Article according to one of claims 9 to 11, characterized in that that he is structured as follows: - one body made of plastic or a basic body with plastic surfaces, - one itself on the main body located layer of copper or nickel, this copper layer or nickel layer mechanically surface-treated, preferably brushed is and - one Palladium-nickel layer on the surface-treated copper layer or nickel layer. Article according to one of claims 9 to 11, characterized in that that he is structured as follows: - one body made of plastic or a basic body with plastic surfaces, - one itself on the main body copper layer, - one on the copper layer located nickel layer, this nickel layer being mechanically surface-treated, preferably brushed is and - one Palladium-nickel layer on the surface-treated nickel layer. Article according to claim 13, characterized in that itself between the surface treated Nickel layer and the palladium-nickel layer another nickel layer located. Article according to one of claims 12 to 14, characterized in that that it the surface treated Nickel layer is a so-called sulfamate nickel layer. Article according to claim 14 or claim 15, characterized characterized it the other nickel layer between the surface treated Nickel layer and the palladium-nickel layer is a so-called sulfamate nickel layer. Article according to one of claims 9 to 16, characterized by at least one siloxane and / or polysiloxane cover layer over the palladi to-nickel layer. Article according to claim 17, characterized in that he is structured as follows: - one body made of plastic or a basic body with plastic surfaces, - one itself on the main body copper layer, - one on the copper layer located nickel layer, preferably sulfamate nickel layer, the mechanical surface treated, preferably brushed is - one yourself on the surface treated Other nickel layer, preferably sulfamate nickel layer, - one palladium-nickel layer located on this further nickel layer, and - one the siloxane / polysiloxane cover layer located on the palladium-nickel layer. Article according to one of claims 9 to 18, characterized in that that the Palladium portion of the palladium-nickel layer at least 50 atom percent, preferably is at least 70 atomic percent, in particular approximately 80 atomic percent. Article according to one of claims 9 to 19, characterized in that that the Layer thickness of the first metal layer on the object, in particular a copper layer, between 10 μm and 60 μm, preferably between 20 μm and 50 μm, in particular between 30 μm and 40 μm is. Article according to one of claims 9 to 20, characterized in that that the Layer thickness of the nickel layers, preferably that on a surface treated Layer of nickel layers, between 5 microns and 25 microns, preferably between 5 microns and 15 microns, in particular between 6 μm and 10 μm is. Article according to one of claims 9 to 21, characterized in that that the Layer thickness of the palladium-nickel layers between 0.1 μm and 5 μm, preferably between 0.2 μm and 2 μm, in particular between 0.5 μm and 1 μm is. Article according to one of claims 17 to 22, characterized in that that the Layer thickness of the siloxane / polysiloxane layer less than 5 microns, preferably less than 1 μm is. Article according to one of claims 9 to 23, characterized in that that it the plastic is ABS. Article according to one of claims 9 to 24, characterized in that that he has a so-called stainless steel look.