WO2004099460A2

WO2004099460A2 - Method for producing galvanically enhanced moulded elements optionally lighted by transparency,made of thermoplastic,thermosetting plastic,elastomer or silicone, as well as moulded elements optionally lighted by transparency made of thermoplastic,thermosetting plastic,elastomer or silicone with galvanically enhanced surface

Info

Publication number: WO2004099460A2
Application number: PCT/EP2004/004832
Authority: WO
Inventors: Dirk Kieslich
Original assignee: Dirk Kieslich
Priority date: 2003-05-07
Filing date: 2004-05-06
Publication date: 2004-11-18
Also published as: WO2004099460B8; WO2004099460A3; DE20321779U1; WO2004099460B1; DE10320237A1; DE10320237B4

Abstract

The invention concerns method for producing galvanically enhanced moulded elements optionally lighted by transparency. The inventive method consists in coating the surface of a moulded element (1) made of thermoplastic, thermosetting plastic, elastomer or transparent amorphous silicone with an opaque or tinted galvanizable plastic layer and/or at least a metal layer (2); optionally treating with laser by removing at least part of the surface of the galvanizable plastic and/or metal layer (2), in particular in the zone of the symbol(s) (5) and applying a galvanic plastic layer (6) on the opaque or tinted galvanizable and/or metal layer (2). The invention also concerns corresponding moulded elements and their uses.

Description

Process for the production of, if appropriate, radiolucent, electroplated moldings made of thermoplastic, thermoset, elastomer or silicone and, if applicable, fluoroscopic moldings made of thermoplastic, thermoset, elastomer or silicone with electroplated surface

The invention relates to a method for producing preferably radiolucent, electroplated moldings made of thermoplastic, thermoset, elastomer or silicone with symbols and with a preferably electroplated cover layer.

Field of application of the invention are molded articles made of thermoplastic, thermoset, elastomer or silicone, in particular with translucent structures, symbols or patterns. This applies in particular to and in motor vehicles for switches, controls, dashboards, slide trains, emblems and the like as well as for retrofit and accessory parts such as Car radios, door sill covers, etc. These molded parts made of thermoplastic, thermoset, elastomer or silicone are normally not galvanizable. However, the use of galvanic surfaces is sought for design reasons. The illumination of the symbols is required as a day / night design. Further areas of application of the invention are electrical devices, electronic devices and control and display elements of all types, audio and video devices, devices and control and display elements of information, telecommunications and domestic technology as well as products of control technology such as switching devices, cabinets, systems and consoles, e.g. Production, plant and building control systems.

According to the prior art, such molded articles made of thermoplastic for the vehicle interior with function-describing and / or position-indicating symbols for fluoroscopy in day / night design, for. B. Turn handles for air conditioning modules or window switches manufactured as follows: A. Production of control elements in the 2-component injection molding process.

Here you can either form the later illuminable, indicating and function-describing symbol from a clear or colored light-conducting material such as PC as a pre-molded part, which is then either automatically rotated into a second cavity by suitable plastic injection molding tools or successively in a cavity by retracting the appropriate sprue a gate valve is overmolded with a second, usually black, plastic compound. In today's widely used technology, a clear polycarbonate pre-molded part is overmolded with a black or similar ABS / PC blend (e.g. Bayblend® T65) or ABS. Since both materials form a chemical bond, the pre-molded part is an integral part of the article. The pre-molded part is embedded in the overmolding and, since it stands through the visible surface, can be illuminated or illuminated from behind with a light source. You can also e.g. in a milky, cloudy, translucent PC that appears white in the day design and then, depending on the lighting color, can be illuminated in a different color in the night design.

The process requires an expensive plastic injection molding tool and a 2-component injection molding machine with associated peripherals. The costs for this are double that of a conventional tool and a conventional machine. Production is therefore only worthwhile from a very large number. Furthermore, the design of the symbol is not easily variable. You are bound to the shaping injection molding tool with the generated symbol. If you want to change the symbol, vary the shape and position, either a new tool must be built or at least new tool inserts.

The main disadvantage, however, is the transition from the ABS or ABS / PC layer to the translucent PC layer of the symbol. This method of the manufacturing process creates fine imperfections that cannot be eliminated, similar to hairline cracks. The materials injected one after the other do not result in a clean chemical bond between the layers when the flow fronts cool down. Venting problems on the symbol sometimes lead to considerably larger "holes and gorges" in the Composite. If the electroplating process subsequently begins, solutions in the electroplating basin and partially trapped air lead to misalignments at the transition from the metal layer to the free layer. The litigation of. Electroplating is never safe to produce here, the transition layer is always unclean or there are even imperfections up to overgrowth. Waste numbers and therefore enormous costs are the result. ,

B. Manufacturing of operating elements by painting and subsequent lasering of symbols.

Here, control elements are made of a clear or translucent PC or PMMA, which are subsequently completely painted. By lasering out paint areas with special laser cutting machines, symbols can now be burned from the paint layer. There are hardly any limits to the freedom of design with regard to the execution of the symbols, since different layers of paint and colors can be applied and the areas to be lasered can be quickly modified. The lasered areas can be X-rayed, but chrome plating is not possible.

C. Manufacture of Control Elements Using IMD (In Mold Decoration) Technology

A clear, usually polycarbonate film is printed in color on the back by screen printing. The design is almost completely free, you can print multicolored symbols one after the other and implement a differently colored night design with a final printed layer. By automatically or manually inserting the foils into a special injection molding tool, plastic material is now injected behind the foil, which forms a connection with the paint and the foil. The position-indicating symbols and fields are shielded from the plastic material by cores that press against the film. The film can either be coated black or in a different color using the screen printing process, or only colored symbols can be applied to the otherwise clear film. Depending on the design of the later article, the entire film can only be back-injected with a crystal-clear material and the entire article can be illuminated. Here you can switch individual on and off Do not guarantee symbols as the crystal-clear material layer functions completely as a light guide. Chromium-plated or metallic surfaces cannot be produced with this technology.

In the past, these three described methods A - C were used to implement symbols in day / night design on components, but now, due to the present invention, high-quality metallic surfaces with function-describing, position-indicating and fluorosable symbols can also be produced.

It was not possible in the prior art e.g. Manufacture chrome-coated control buttons with symbols that describe functions, position indicators and X-rays in a day / night design.

The galvanic chrome plating of plastics has so far only been possible on certain materials (ABS or ABS / PC) in large series. Since the copper layer underneath the galvanic chrome layer did not permit lasering and the starting material is not transparent, a significant limitation can be seen from the outset.

An article manufactured using the two-component process or by IMD technology (process A, C) can only be galvanized moderately or not at all.

The trend in the automotive industry, particularly in the automotive industry, is moving more and more towards the unmistakable appearance of their lettering or emblems even at night. So far, lettering has been made from ABS or ABS / PC and subsequently galvanized.

With the new process, emblems can be made from an inexpensive, amorphous material in the future. The lighting is then provided by lasered areas that cannot be seen in daylight and which then illuminate or illuminate the emblem from behind in a diffuse, colorless or colored manner when the vehicle lighting is switched on. The method according to the invention and the moldings obtained in this way provide almost unlimited freedom in terms of the decoration of the surfaces and, in addition, the possibility of realizing luminous symbols. The material dependency on special plastics, so-called galvano types, is also eliminated. It is also possible to implement controls, knobs, switches etc. in chrome or aluminum design with colored function-describing and / or position-indicating symbols that can be illuminated in the night design. This results in cost-effective better and higher-quality equipment features for the vehicle interior and a metallic, cold feel of the surface, which is generally perceived and rewarded as high-quality and noble.

Shaped bodies galvanized in this way can preferably be used in vehicle technology or in other industries, in particular in the case of automobile manufacturers and their suppliers.

The present invention is based on the object of providing a method for producing radiolucent, galvanically refined shaped bodies with symbols which avoids the procedural steps of the technically complex methods of the prior art A to C. Such a method is solved by the method steps of claim 1.

The present invention thus relates to a process for the production, if appropriate, of radiolucent, electroplated moldings by:

- Providing the surface of a molded body made of preferably transparent, amorphous thermoplastic, thermoset, elastomer or silicone with a layer of an opaque or colored galvanized plastic and / or at least one layer of metal;

- if necessary, ablative laser treatment of at least part of the surface of the layer of the galvanizable plastic and / or metal, in particular in the area of the symbol (s / e);

- Applying a galvanic layer to the layer made of galvanizable plastic and / or metal. The invention differs from the prior art in that the galvanizable plastic and / or the metal layer can be applied in a simple manner to the molded body made of thermoplastic, thermoset, elastomer or silicone. Lasering of this plastic layer and / or metal layer is possible without further ado, so that a gap or an area can then be cut out of the plastic layer and / or metal layer as a structure that can be X-rayed. The galvanizable plastic and / or the galvanizable metal layer is missing in the area of this gap / area, so that no electroplating layer is formed there. As a result, this area can be examined.

According to a preferred embodiment of the method according to the invention, this is carried out by providing the molded body with a layer of 10 to 40 μm, in particular 10 to 20 μm, from an opaque or colored galvanized plastic, if necessary, removing laser treatment of at least part of the surface of the layer of the galvanizable plastic , in particular in the area of the symbol (s), applying a metallic electroplating layer of 30 to 100 μm, in particular 30 to 40 μm, to the layer of opaque or colored galvanized plastic.

A transparent amorphous thermoplastic in the sense of the present invention means for example polycarbonate (PC), polymethyl methacrylate (PMMA) or other thermoplastics known to the person skilled in the art. We refer, for example, to Ullmann's Encyklopadie der Technische Chemie, 4th edition, volume 15, 1978, keyword: plastics, order states and properties, page 219 ff.

A thermoset in the sense of the present invention means, for example, epoxy resins, urea-formaldehyde resins, melamine-formaldehyde resins, melamine-phenol-formaldehyde resins, phenol-formaldehyde resins, unsaturated polyester resins. We refer to Römpp, Lexikon Chemie 10th ed. 1997, keyword Duroplast, p. 1060.

An elastomer in the sense of the present invention is understood to mean, for example, synthetic system rubbers, such as polybutadiene, styrene-butadiene rubber, acrylonitrile-butadiene rubber, polychloroprene, polyisoprene, ethylene Propylene rubbers, butyl rubbers, ethylene-vinylene acetate copolymers, acrylate rubbers, epoxy rubbers, fluororubbers, thioplastics, chlorinated polyethylene, chlorosulfonated polyethylene, chlorobutyl rubber and natural rubbers. We refer to Römpp loc. Cit., Keyword elastomers, pp. 1104 - 1106 and to Ulimanns loc. Cit., Volume 13, keyword rubber, synthetic, pp. 595 - 634.

A silicone in the sense of the present invention means, for example, silicone resins and silicone rubbers (= silicone elastomers). We refer to Römpp aaO, keyword Silicone, pp. 4106 - 4111, esp. 4108-4111 and to Ullmanns aaO, Volume 21, 1982 keyword Silicone, Pp. 511 - 540.

A galvanizable plastic in the sense of the present invention means, for example, copolymers of butadiene, such as e.g. Acrylonitrile butadiene styrene (ABS) or ABS / PC.

A metal layer in the sense of the present invention means, for example, corresponding layers of copper, nickel, chromium, aluminum or noble metals such as gold, silver and platinum.

An electroplating layer which is to be used in the sense of the present method is understood to mean, for example, that of copper, nickel, bright nickel or chrome.

A galvanic layer is typically applied to the layer of the preferably opaque or colored galvanizable plastic and / or metal in such a way that, in a first step, the surface is stained with chromic sulfuric acid for the electronic pre-nickel plating to form caverns and then a typical layer of copper, Nickel, bright nickel and chrome or other decorative metals such as aluminum is applied.

According to a further preferred embodiment, an acrylonitrile-budadiene-styrene copolymer (ABS) is used as the galvanizable plastic. According to a further preferred embodiment, such an acrylonitrile-butadiene-styrene copolymer (ABS) is applied as a lacquer.

According to a further preferred embodiment, the production according to the invention is carried out by providing the molded body with a layer of 1 to 10 μm, in particular 2 to 5 μm, of metal by gas-phase deposition, such as CVD or by vacuum coating processes such as PVD sputtering, and optionally ablative laser treatment of at least part of the Surface of the layer of metal, in particular in the area of the symbol (s / e), application of an electroplating layer of 30 to 100 μm, in particular 30 to 40 μm, to the layer of metal. For CVD we refer to Römpp Lexikon Chemie, 10th ed. 1997, keyword gas phase separation, p. 1469, for PVD to ibid., Keyword PVD process, p. 3630 f.

According to a further preferred embodiment, the production according to the invention is carried out by providing the molded body with a layer of 1 to 10 μm, in particular 2 to 5 μm, of metal by gas phase deposition, such as CVD or by vacuum coating methods, such as PVD, sputtering, and optionally ablative laser treatment of at least one part the surface of the layer of metal, especially in the area of the symbol (s / e).

Another object of the present invention is to provide a corresponding radiolucent molded body made of thermoplastic, thermoset, elastomer or silicone, which has been obtained in particular by the aforementioned method and has the features according to claim 7 or 8.

The present invention thus also relates to a radiolucent molded body, in particular obtainable according to the aforementioned production claims, from a transparent amorphous plastic, wherein in an opaque or colored layer covering the amorphous plastic with a thickness of 10 to 40 μm, in particular 10 to 20 μm, of a galvanizable Plastic and / or metal, if necessary, the symbols are designed as patterns and an electroplating layer leaves the contour of the pattern free. If the electroplated, refined shaped bodies are used as covers, emblems or decorative strips, that is to say as products which are not backlit, an additional laser treatment for inserting symbols into the plastic metal layer is not necessary.

The present invention finally relates to the use of the moldings produced by the above processes for indoor and outdoor applications, preferably in automotive engineering.

An embodiment is explained with reference to the drawing, in which:

1 is a view of a plastic part,

2 shows the application of a galvanizable plastic or a metal layer,

3 shows the production of symbols by a laser beam and

4 shows the finished metallized plastic part.

Fig. 1 shows a molded part made of thermoplastic, thermoset, elastomer or silicone 1 made of a transparent or translucent, amorphous plastic. It is e.g. a switch button, a rocker panel, an instrument panel, an information panel or the like. This plastic cannot be galvanized.

2, an opaque or colored lacquer layer 2 made of a galvanizable plastic such as an acrylonitrile-butadiene-styrene copolymer (ABS) or a metal layer 2 is applied to the molded part 1. The layer 2 is shown too thick in comparison to the molded part 1. In this respect, the drawing is not to scale.

In a further method step according to FIG. 3, a symbol 5 or a structure 5 is burned into the lacquer layer 2 or metal layer 2 by a laser beam 3 which displaces or burns a laser cutting system 4. The laser beam penetrates to the depth of the lacquer layer or the metal layer by displacing and / or burning the material of this layer and does not damage the layer 1 underneath. Such control of the laser beam is possible. Finally, according to FIG. 4, an electroplating layer 6 is formed using standardized methods. After the surface has been heated, electrolytic nickel plating takes place. Further layers of copper, nickel, bright nickel and chrome are then electroplated. Since there is no electrically conductive layer in the area of the symbols, a radiolucent area is obtained there. The layer 6 is shown too thick compared to the molded part 1. In this respect, the drawing is not to scale.

The present invention is further illustrated by working examples in the form of manufacturing examples.

Manufacturing Example 1:

In a high-pressure vacuum, a metallic thin layer of 1 to 10 μm, in particular approximately 2 to 5 μm, made of chromium is applied to the shaped body substrate by physical vapor deposition (PVD), from which symbols which can be illuminated are subsequently lasered out. In contrast to the previously described methods, the metallic coating is only applied in the minimal μm range. However, due to its low layer thickness, it is so sensitive to abrasion or scratching that a subsequent clear protective coating or coating is required to protect the surface. The attributes that are generally found to be noble and which can be found in the galvanic chrome plating of the surface and which determine the gloss and feel are not given here. On the one hand, the brilliance of the metallic surface is reduced by the subsequent protective coating and / or protective coating, and on the other hand, the feel is warmer due to the minimal metallic coating, i.e. the molded body "is felt", the typical "metal feeling" is missing.

Manufacturing Example 2:

By means of the PVD technology, a copper layer is applied in the few micrometer range, preferably approximately 2 to 5 μm, which can be lasered due to its low layer thickness. A standardized plastic electroplating is then used, but with the pickling process, the metallic nucleation and the application of the copper are ignored. In this way, plastics can also be galvanized and the realization of translucent symbols can be achieved.

In the method according to the invention, the article is made entirely of a transparent plastic (PC / PMMA or the like). A subsequent coating with a galvanizable ABS layer by painting ensures the subsequent metallization of the surface. Painting the plastic parts does not mean a problematic process. Painting of plastic articles is technically feasible and has been established as a standard process for years. What is decisive here, however, is a prerequisite for the clean next work step that the plastic paint has a certain minimum color. After painting the ABS layer, the desired symbol is burned out of the paint and only then is the component electroplated.

Rejects are included in the entire process according to the invention:

■ Article injection molding: less than 1%. No complexity of the component and the process control. Standard tools and machines can be used.

■ Painting the articles: less than 5%. Process control is safe, rejects due to contamination / turbulence when applying paint are technically hardly avoidable. However, slight contamination is then concealed by the metal layer.

■ Lasering of symbols: below 1% to almost 0%.

■ Chrome plating of the articles: as standard - depending on the know-how of the electroplating companies - at approx. 5 - 10%.

The advantages of the method according to the invention:

► Control elements, rotary knobs, switches etc. with a metallic surface and function-describing, position-indicating symbols that are used in the night design can be screened.

► Almost limitless freedom when it comes to decorating the surfaces and also the option of realizing various illuminated symbols, signs, structures and patterns without tool costs.

► Better and high-quality equipment features in the vehicle interior (optics & haptics).

► Better dimensional stability of the molded parts due to the possibility of using thermoplastics, thermosets, elastomers or silicones at temperatures above 70 ° C in the manufacturing process and later use

► The only truly economical and stable process whose high-quality products also meet the high quality requirements of the automotive industry:

- Temperature change test (DIN 53 498A): passed

- Climate change test (DIN 50 017KK): passed

- CASS test (saline spray test) (DIN 50 021): passed

Claims

claims

1. Process for the production of, if appropriate, radiolucent, galvanically refined shaped bodies, characterized by:

- Providing the surface of a molded body made of transparent, amorphous thermoplastic, thermoset, elastomer or silicone with a layer of an opaque or colored galvanized plastic and / or at least one layer of metal;

- Applying a galvanic layer on the layer of opaque or colored galvanizable plastic and / or metal.

2. The method according to claim 1, characterized by:

Providing the molded body with a layer of 10 to 40 μm, in particular 10 to 20 μm, of an opaque or colored galvanized plastic,

- if necessary, ablative laser treatment of at least part of the surface of the layer of the galvanizable plastic, in particular in the area of the symbol (s / e);

- Application of a galvanic layer of 30 to 100 μm, in particular 30 to 40 μm, on the layer made of opaque or colored galvanized plastic.

3. The method according to claim 1, characterized by:

- Providing the molded body with a layer of 1 to 10 microns, in particular 2 to 5 microns made of metal by gas phase deposition, such as CVD or by vacuum coating processes, such as PVD, sputtering

- if necessary, ablative laser treatment of at least part of the surface of the layer of the metal, in particular in the area of the symbol (s / e); - Applying an electroplating layer of 30 to 100 microns, in particular 30 to 40 microns on the layer of metal.

A method according to claim 1, characterized by:

- Providing the molded body with a layer of 1 to 10 μm, in particular 2 to 5 μm, of metal by gas phase deposition, such as CVD or by vacuum coating processes, such as PVD, sputtering,

if necessary, ablative laser treatment of at least part of the surface of the layer of metal, in particular in the area of the Ix symbol (s / e).

5. The method according to claim 1 or 2, characterized in that an acrylonitrile-butadiene-styrene copolymer (ABS) is used as the galvanizable plastic.

6. The method according to claim 5, characterized in that the acylnitrile-butadiene-styrene copolymer (ABS) is applied as a lacquer.

7. X-ray shaped body, in particular obtainable according to any one of claims 1 to 6, made of a transparent, amorphous plastic, in an opaque or colored layer covering the amorphous plastic with a thickness of 10 to 40 μm, in particular 10 to 20 μm, if necessary the symbols are formed from a galvanizable plastic and / or metal as a pattern and that a galvanic layer leaves the contour of the pattern free.

8. X-ray shaped body, in particular obtainable according to any one of claims 1 to 6, made of a transparent, amorphous plastic, wherein in a layer covering the amorphous plastic made of metal with the thickness of 1 to 10 microns, in particular 2 to 5 microns from a galvanizable metal where appropriate, the symbols are designed as patterns and that an electroplating layer may leave the contour of the pattern free.

9. Non-radiolucent molded body, in particular available according to any one of claims 1 to 6 made of a thermoplastic, thermoset, elastomer or silicone, the process of lasering symbols completely being eliminated.

10. Non-radiolucent molded body, in particular obtainable according to any one of claims 1 to 6 made of a thermoplastic, thermoset, elastomer or silicone, the process of lasering symbols only being carried out after application of the uppermost metal layer for engraving symbols.

11. Use of the shaped bodies according to any one of claims 7 to 10, in particular obtainable by the process according to any one of claims 1 to 6 for indoor and outdoor applications, in particular in automotive engineering.