KR20120099755A - Device and method for electrically contacting treatment material in electroplating systems - Google Patents

Abstract

The present invention relates to the electrical contact of a material 1 in the form of a band or plate, which material can be conveyed via an electroplating system on a transport track. A cathode 6 contact means 6 is placed on the lower surface of the material 1, for example in the electrolyte 12, which is circulated in the electroplating system. The material is in electrical contact to deliver a current to the material 1. In the prior art, the contact means 6 are metal coated in addition to the material 1. The metal coating is clearly removed continuously due to contact. According to the invention, for example, each tubular contact means 6 is cooled by a cooling unit or a cooling medium. If the temperature difference between the operating temperature of the electrolyte 12 and the surface temperature of the contact means 6 is large enough, no metal is deposited on the cooled surface of the contact means 6. This property can be added to the surface of the contact means 6 which cannot be metal coated with the cathode in the electrolyte 12 used.

Description

DEVICE AND METHOD FOR ELECTRICALLY CONTACTING TREATMENT MATERIAL IN ELECTROPLATING SYSTEMS}

The present invention relates to the electrical contact of a material to be electroplated in an electroplating system.

Chemical wet systems suitable for this purpose include immersion bath systems, drum systems, continuous flow systems and systems for roll to roll tape shaped materials, as well as other electroplating equipment. Materials to be electroplated include, for example, piece materials, plate-shaped materials, thin films and tapes made of metals, plastics, ceramics, glass and other materials that are at least partially electrically conductive on the surface. Examples include metal workpieces, circuit boards or conductor thin films, wafers and solar cells.

The entire area or structured area of the electrically conductive surface of the material to be electrochemically treated using the method of the present invention must be cathodically disposed in the electrolyte with the anode. This requires the use of at least a rectifier or pulse rectifier, the cathode of the rectifier or pulse rectifier being connected to the surface of the material to be treated and the anode of the rectifier or pulse rectifier being connected to an anode of at least one electrically conductive electrolyzer.

In immersion plating, the cathode material is brought into electrical contact with the frame and the material carrier, for example by contact. In continuous flow plating, the material is in continuous or discontinuous electrical contact with the conveying means which rotates or clamps. In roll to roll plating, for example, contact rollers make electrical contact. Because of their cathode polarity, these contact means and / or transfer means are electroplated almost similar to the surface of the material itself. This metallization of the contact means is very problematic for all the various types of electroplating. The contact means must be continuously de-metalized. Various solutions are already known for this purpose. In periodically operated penetration plating systems, the frame contacts attached to the material carrier must be demetallized at regular intervals in a particular process. This demetallization does not cause any particular technical problem, but it is very disadvantageous from an economic point of view. In the case of a continuous flow system, the contact means must be separated during continuous electroplating. Proven technical solutions are already known to solve these technical problems.

According to the prior art, the electrical contact means is electrochemically demetallized, ie etched. For this purpose, these means are connected anodically. In order to ensure that the contact means themselves are not etched, the contact means must be made of an anode material that is resistant to the electrolyte used, at least on its surface.

Surfaces of anode resistant materials such as titanium, niobium or decarburization are oxidized in the most commonly used acidic electrolytes. This thin oxide film is an electrical insulator. Indeed, electrical conduction or contact is achieved through the remaining pores in the oxide layer and by applying pressure and / or friction to the contact partner. Applying pressure or friction to the material through contact is not possible in the case of materials that are difficult to handle, such as glass. To prevent destruction of this material, rolling contacts and other rotating conveying means can be used to apply only a small force to the material. This means that the metal whose surface is oxidized is almost completely excluded in use as a connecting means. Here, non-oxidizing materials such as precious metals are required for the coating of the contact means.

It has also been shown through practice that metals with oxidized surfaces or on which metal oxide layers are deposited may only undergo incomplete electrolytic demetallization. This metallization residue remains as particles sticking to the oxide layer. Thus, the surface of such contact means is also provided with a precious metal coating. This solves the problem of the insulating oxide layer.

However, plating the oxidizing metal of the contact in a manner that is permanently tacky and resistant to abrasion, although not impossible, is technically very difficult. In practice, this contact must be rolled, for example, on a circuit board with sharp edges. As a result, rapid wear of the precious metal coating occurs, thereby reducing the efficiency of the overall flow system.

If fragile materials such as glass disks have to be electrochemically treated, hard metallic conveying means and contacting means are almost impossible to use. At least the surface of the conveying means and / or the contact means needs to comprise an elastic material. The contact means must also be electrically conductive. According to the prior art, this can be achieved through metal / plastic composites that provide sufficiently good electrical conductivity, especially when the composite material is locally compressed in the temporary contact area.

The conductivity is achieved through chemically and electrochemically stable metal particles or carbon particles, for example, incorporated into the elastomer or rubber.

It is an object of the present invention to provide an apparatus and a method for enabling electrical contact of a material to be electroplated in all types of electroplating systems by simple fixed or rotary contacts, whereby the contact prevents metal It is to provide an equipment and method that will not be converted. Surface to be electroplated means either the entire surface or a structured surface. Such a structure can be formed by a resist on an electrically conductive seed layer, or by a printed circuit pattern that is electrically conductive, for example, as a seed layer on an insulating substrate.

The above object is achieved by a device according to patent claims 1 and 7 and by a method according to patent claims 4 and 10. Possible additions and combinations of the invention are described in the dependent claims.

The contact means consists of fixed or rotary contacts. Fixed contact means contact with a material, for example in an immersion system. A rotating contact wheel or contact roller in a continuous flow system contacts the product transversely with respect to the conveying direction on at least one contact track or over the entire width of the material. A rigid or elastic contact wheel or contact roller is electrically conductive to its surface at least about its rolling. Only a small part of the rotary contact means according to the invention is located temporarily in the region of the electrolyzer, ie in the part of the electric field present between the material to be electroplated as a cathode and the soluble or insoluble anode. The cathode contact means and the remaining area of the contact wheel or contact roller are shielded from the electric field of the electrolyzer (s) by an electrically nonconductive shield. The contact means are not metallized in the shielding area. Thus, only a small part of the contact wheel or contact roller can be continuously electroplated, ie the part is close to the cathode material and thus lies in the electrolyzer and its electric field.

For example, in the case of fixed contact means of the frame in an immersion bath system or contact tracks of sliding contacts as well as clamping contacts in a continuous flow system, the same area in electrical contact with the product is always exposed to the electric field of the electrolyzer. This region of the contact means exposed to the electric field of the electrolyzer can be metallized like the material itself.

The difficulty of such electroplating can be solved by cooling the contact means in the first aspect of the present invention and by using a contact forming material that does not cause electrochemical metallization in the electrolyte used in the second aspect.

The electrolyte is required to be at a particular operating temperature for electrochemical deposition, in particular for adhesion and proper electroplating. Below this operating temperature, the deposited metal is not industrially available, or no deposition takes place at all. As the difference between the operating temperature of the electrolyte and the surface temperature of the contacting means increases, the above-mentioned deposition decreases or no deposition takes place. In practice, the operating temperature of the electrolyte is usually 30 ° C to 80 ° C. Typical liquid cooling medium temperatures are, for example, 8 ° C. Even lower temperatures can be obtained using conventional cooling devices such as compressors, vaporizers, heat exchanger Peltier elements and the like. Thus, a sufficiently large difference can be obtained between the operating temperature of the electrolyte and the surface temperature of the contact means, whereby no deposition of metal is made on the cathode surface of the contact means.

With a given electrolyte, electrochemical plating is not possible for all materials and electrically conductive surfaces. This fact is used in further aspects of the invention. An electrically non-insulated surface of at least the cathode contact means is made of such a non-metallizable material. By way of example, there is at least a contact means consisting of tin or niobium on the surface. For example, there is no electrochemical metallization in a hard chromium bath.

In addition, according to the present invention, a combination of contactless cooling and material which is not metallized or hardly metallized in the subject electrolyte at selected operating temperatures of the electrolyte is possible.

In all cases, the material to be electroplated is in electrical contact, so that the contacts are not permanently metallized and thus do not need to be demetallized separately. Thus, no contact means of polarity which is etched as an anode is required.

The contact means according to the invention need not be polarized to the anode, but instead the fact that the cathodes are constantly connected in a cathodic manner for the electroplating process means that an electrically conductive material or similar filler is chemically stable and electrochemically in the electrolyte. If not stable, this means that this electrically conductive material or similar filler can also be used for this. Such materials, such as stainless steel, are significantly cheaper than other stable anode metals such as titanium, niobium or tantalum. In copper sulfate electrolytes, suitable stainless steels are those having the trade name Hastelloy C, for example. These materials can also be economically treated than the electrochemically resistant metals described above. A further advantage is that an insulating oxide layer, for example, in which the stainless steel in the electrolyte is problematic on the surface of the contact of galvanic aggregates, on the operating surface of the contact wheel, or on the sliding surface of the sliding contact It does not form.

Thus, compared with oxidizing metals, this results in much smaller electrical transition resistance at the point of contact. It is thus heated to some extent, thereby assisting both the material as well as the contact means, i.e., as far as wear is concerned. Good electrical contact of mainly non-oxidizing materials on the contact means also requires smaller contact forces, thus preventing deformation or embossing, for example, of thin films, even when using hard contact means. The same applies to the internal connection of the electrically conductive particles of the filler in the elastic composite material. Small contact boundary resistance of the filler to the material also occurs in the case of such elastic contact means.

Particularly in the case of aggressive electrolytes, cases may arise where the non-oxidizing materials available for the contact wheels are not sufficiently chemically stable. In this case, the contact means is provided with an electrically conductive protective layer at least on the contact surface. Coatings with an electrically conductive diamond layer in addition to the precious metal are particularly suitable for this purpose, which is also particularly resistant to mechanical polishing. For example, the conductivity of a diamond layer 5 micron to 10 micron thick is produced, for example, by doping with boron. The surface of the contacts coated in this way is similar to the metallic contact material. Electrochemical metallization of the material is prevented by cooling the contact means according to the invention and / or using an electrolyte in which no metal is deposited on the diamond coating. In contrast to possible precious metal coatings, diamond coatings are extremely resistant to abrasion and abrasion. This property is a major additional advantage, in particular for rotary or sliding contacts according to the invention in continuous flow plating systems.

Of course, diamond coatings are also suitable for oxidizing materials such as titanium. Contact wheels and contact rollers made of stainless steel, with or without diamond coating, are preferred when practicing the present invention.

The effectiveness of the present invention, i.e. the prevention of permanent metallization on the contact means, can be increased if necessary and in combination with chemical electroless etching, especially when the operating temperature of the electrolyte is close to ambient temperature. As an etchant, an electrolyte of an electrolytic cell or an operation container in which plating is performed may be used. In many plating baths, the electrolyte used for the deposited metal has a remelting effect, i.e., etching characteristics, as in the case of using a copper electrolyte based on sulfuric acid. This property is used for assisted demetallization of the contact means in accordance with the invention when the cooling of the contact means or the choice of electrolyte is not sufficient, ie when metal is deposited slightly on the cooled contact means.

The electrolyte is supplied by circulation through the container for the material during plating. A portion of this electrolyte flow is supplied as an etchant, for example by an electrolyte transport device, to the surface of the contact means to be demetallized, and then flows strongly outside the electrolyzer of the electroplating process and close to these contact means. . This results in very little metallization, which may have been deposited on the contact wheels in the electrolytic cell at every turn, even though the cooling material and / or the individual contact materials are redissolved immediately.

In addition to a strong flow of etch electrolyte under significant pressure, other physical and / or chemical devices or measures may be used to enhance the effect of such chemical etching on the surface of the contacting means.

In this embodiment the etching rate is substantially increased when this partial flow of electrolyte is heated, for example when heated to 70 ° C., ie higher than the low operating temperature in an operating container, for example 30 ° C.

The electrolyte flowing into the contacting means is enriched with at least one oxidant, such as ozone, oxygen, air, atmospheric oxygen, hydrogen peroxide or peracid, which is compatible with each electrolyte in the electroplating process.

Due to the constant consumption of chemicals and the loss of the electrolyte from the working container by the discharged material, the additives in the electrolyte must be constantly replenished. The particular agent to be administered may have etching properties for the deposited metalization. One example is the chloride used in copper sulphate baths for printed circuit boards, which can be sprayed, ie added in the form of salts to the electrolyte flowing against the contact means.

Depending on the nature and concentration of the additives in the electrolyte, the aforementioned measures for increasing the etch rate of the etch electrolyte flowing to the contact means can be combined with cooling of such contact means.

When using an insoluble anode, the electrolyte must be continuously replenished or regenerated with each metal ion of the metal deposit. This can be done with an appropriate salt. The method described in publication DD215589 A1 is also suitable for this purpose. The material is added to the electrolyte in the form of an electrochemically reversible redox system. This material or redox agent is conveyed with the electrolyte through the working container and regeneration chamber in the circuit. It is oxidized at the anode and reduced again in the regeneration zone by electroless decomposition dissolution of the regenerative metal. The metal dissolved in this manner is deposited on the cathode material in the electrolytic cell by an electroplating current source. An example of this is sulfuric acid electrolytes as used in printed circuit board production. Iron is used as redox agent. In the working container and in the regeneration zone, the following reactions mainly occur during these processes.

In a working container,

Anode: Fe ^{2 +} -1e → Fe ^{3 +}

Cathode, Material: Cu ^{2 +} + 2e → Cu ⁰

In the regeneration zone: Cu ⁰ + Fe ^{3 +} → Cu ^{2 +} + Fe ^{2 +}

In the insoluble anode, in this example oxide reducing agent it is oxidized in the iron is gatneunde the Fe ^{3 +} as the ion, which has the ability to dissolve the copper. This is very advantageously used in other aspects of the invention for the combined electroless dissolution of copper, which can still be deposited on the cooled contact means according to the invention. To do this, part of the circulating electrolyte rich in Fe ³⁺ diverges from the region of the anode of the electrolyzer and undergoes a strong flow to the contact means, ideally flowing away from the surface of the material.

According to the present invention, an apparatus and method for enabling electrical contact of a material to be electroplated in all types of electroplating systems by simple fixed or rotary contacts, thereby avoiding the disadvantages of the prior art, thereby making the contact metallized. Equipment and methods that are not available.

The invention will be explained with reference to FIGS. 1 to 5, which are not schematically and to scale.
FIG. 1 shows in two views a situation relating to a first aspect of contact for one-sided contact of a tape-shaped material with no rotating or sliding contact means in a continuous flow system.
2 shows a side view of the structure of the electrical contact embodiment of FIG. 1 as a section of a continuous flow system.
FIG. 3 shows two views of the second contact embodiment, in particular with respect to the material in the form of a plate, with contact means rotating with rotary feed-throughs in a continuous flow system.
FIG. 4 shows two views of a third contact embodiment, in particular with a plate-shaped material, with a rotating contact means and a non-rotating cooling pipe in a continuous flow system.
FIG. 5 is a side view of the continuous flow system, showing a side view of the continuous flow system in which the electroless demetallization of the residual amount of possible metal deposition on such contact means and the cooled contact means are combined.
FIG. 6 shows three views of the continuous flow system, three views of the continuous flow system in which material is supplied through the working container as a body rotating on electrically sliding sliding rails.

In a first aspect of the invention, the contact means, which is a cathode, is cooled to prevent contact metallization. In a second aspect of the invention, a contact material which is not metallizable in the electrolyte is used.

The first aspect of the invention describes an example of a tubular hollow body for contacting means in a continuous flow system in which a cooling medium traverses the tubular hollow body. Especially in the case where the material to be electroplated is a material having a small width perpendicular to the conveying direction, other cooling methods such as Peltier elements can also be used advantageously. In this case, a solid body made of a material which provides good electrical and thermal conductivity such as copper can also be used as the contact means. The coolant is then introduced from one or both sides of the contact means.

In a second aspect of the invention with a suitable material on the surface of the contact means, cooling can in principle be ruled out. In this case, no hollow body is needed for the contact means.

The third aspect of the present invention is a combination of the first aspect using the second aspect of the present invention or a combination of the second aspect using the first aspect. In all cases, the complete prevention of any possible metallization of the contact means can be achieved via additional electroless etching, ie chemical etching, if necessary.

The invention is described with an example of a continuous flow system. This is also suitable for all other known plating systems such as immersion bath systems and drum systems.

1 shows a first contact material with respect to a first contact material, preferably tape-shaped material 1, supplied through a continuous flow system. The material 1 is electroplated only on one side, in this case only on the bottom. An example of the material 1 is an RFID antenna which is supplied on a roll-to-roll and mounted on a tape-shaped electrically insulating substrate that is electroplated. In one of the plurality of contacts along the continuous flow system the contact means 6 is arranged on the side on which the material is electroplated in a fixed, ie non-rotating manner. The tape or substrate of material 1 is pulled by at least one known winding device through a continuous flow system. This slides the structure over the sliding electrical contact 6 while maintaining electrical contact. To support tape conveyance, the weight roller 16 can be driven in a way that rotates along the unplated top. This weight roller 16 may preferably have an electrically insulating material on its surface. Such materials may be hard or soft. On the one hand, this elasticity increases the length of the electrical contact on the weight roller 16 in the conveying direction, while on the other hand, the weight roller 16 reduces or prevents tension of the tape. Thus, each driven weight roller 16 is effective in feeding the material 1 through a continuous flow system. Due to the larger contact area, the current density for the contact means 6 is reduced, which reduces the potential wear of the contact means 6 described above.

It is possible to arrange so that the weight roller 16 in the installation position only rotates. According to the given number of contact means 6 along the conveying path of the continuous flow system, the drawing rollers can be arranged on both sides to withstand the advancing of the tape. The tape slides so that the sides are in contact and in this embodiment are electroplated over the contact means 6 which are formed as a hollow body and which are fixedly arranged.

According to the invention, the liquid or gaseous refrigerant 5 or the cooling medium flows through the non-rotating tubular contact means 6, which extends at least partially perpendicular to the conveying direction over the material 1. do. The refrigerant flow pipe 4 is flange mounted directly on the contact means 6. Similarly, the refrigerant return pipe 8 directly flanged is placed on the opposite side of the continuous flow system.

The working container 14 houses at least one soluble or insoluble anode 10, which forms an electrolytic cell 11 with the surface being polarized as the cathode of the material 1. The electrolyzer 11 receives the electrolyte 12, where the level 13 of electrolyte reaches at least as far as the bottom surface of the material 1. In this way, the electric field originating from the anode 10 cannot reach the contact means 6 because the contact means is almost completely protected by the electrical insulation 22. The small surface line on which only a substrate of material 1 slides there is no insulation 22. However, this region can be electroplated just like the material 1. In order to prevent this from happening, the contact means 6 is cooled in the first aspect of the invention. On the cathode surface having a temperature much lower than the operating temperature of the electrolyte, no metal is deposited at least in the electrolyte bath, which is configured for high operating temperatures. It is advantageous that the difference between the required operating temperature of the electrolyte and the surface temperature of the contact means 6 is as large as possible. This is actually a very frequent case. The tape shaped material 1 can be electroplated in a very simple aspect of the invention with low cost and minimal maintenance. Otherwise demetallization of the contact means 6 which is very expensive is not required.

In order to achieve the required contact force between the material 1 and the contact means 6, a certain angle of contact can also be chosen. 1 shows a weight roller 16. It exerts a contact force on the contact means 6, which rests on its tape-like material 1 under its own weight and are thus positioned across. This weight roller 16 can be mounted to rotate and rotated by a tape, or the weight roller can be rotated by the drive 3 to support the conveying part. The electrical lead 23 connects the electrode of the electrolytic cell with the plating rectifier (s).

FIG. 2 shows a side view of the situation of FIG. 1 with several contact means 6 along a transport path of a continuous flow system. The insulation 22 in the cooled contact means 6 almost reaches the material 1. In addition, the insulation 22 can be reliably seated on the tubular contact means 6. This not only acts as an electrical insulator but also as a heat insulator for the flowing refrigerant 5. The cross section of the hollow body of the contact means may deviate from the circular shape shown, for example rectangular and preferably a narrow side lies in the conveying direction, so that the space obtained thereby can be used for the longer anode 10 in the conveying direction. have. The weight roller 16, which is not in electrical contact, can be driven as shown. The broken line represents an alternative configuration of the weight roller 16 driven between the contact means 6, thus also forming a wrap angle with the contact means 6 together with the formation of a corresponding contact force. Arrow 24 indicates the conveying direction.

The aspect of the invention according to the contact aspect shown in FIGS. 1 and 2 is suitable for the conventional application of using tape-shaped material 1. These embodiments are particularly cost effective. For the plate-shaped material 1, a rotating wheel or roller is usually required as the contact means 2, so that the contact means can act simultaneously as a conveying means for the material 1. Another figure illustrates this aspect.

In FIG. 3, the material 1 is electrochemically metallized only on the bottom surface. The illustrated contact means 2 has a tubular shape. The contact means are mounted to rotate in the working container 14, for example by means of a drive 3, such as a spur gear, so that the material 1 is conveyed perpendicularly to the plane via a continuous flow system. Along the transport path, there are usually many such contact means 2. The fixedly arranged refrigerant flow pipe 4 transfers the refrigerant 5 to the first rotary feedthrough 7. From there, the coolant flows through the tubular contact means 2, whereby the surface of the contact means 2 is assumed to be in fact the temperature of the coolant 5. The refrigerant flows into the refrigerant return pipe 8 which is fixedly arranged through the second rotary feedthrough 7. The current required for electroplating reaches the electrical conductor 23 and the contact means 2 which rotates, for example by sliding contact 9 or by rotating contact. The contact means 2 rotates over the material 1, which may be plate-shaped or tape-shaped. In this way, the lower surface of the material 1 is in electrical contact. Material 1 forms electrolyzer 11 together with anode 10. It is located in the electrolyte 12 such that the level 13 in the working container 14 extends at least to the material 1 to be coated. In this way, the contact means 2 remains largely free of electric fields originating from the anode 10, since there is a shield 15 located above the metallic contact means 2. This extends close to the surface of the material 1. This supports the demetallization achieved by the contact means 2. Known circulating elements, which are required for electroplating of the circulating electrolyte, are not shown in this and the other figures.

Above all, certain contact forces are required for reliable electrical contact. This can be formed in the contact means 2 in the case of a tape-shaped material 1, for example by forming an enveloping angle. The figures herein show how the contact force is produced by the weight roller 16, which rests on the material 1 under its own weight. This weight roller 16 can be driven to rotate by, for example, a belt drive or a gear drive to support the transport of the material 1. In particular, in the case of tape-shaped material 1, it may be sufficient that the weight roller 16 is simply rotated and not driven at that point.

The side view of FIG. 3 shows the cross section A-B. Here too, it can be seen that aspects of the present invention are simple to implement. Two rotary feedthroughs 7 are required for the contact aspect. However, these feedthroughs represent a significant cost factor, since a large number of contact means 2 are required in a continuous flow system. This is the case, for example, when the electrically insulating substrate is to be electroplated as a plate-shaped structure insulated from each other and small in the conveying direction. An example of such a situation is electroplating of an RFID antenna, where the RFID antenna can be placed on a plate. The aspect of the invention according to FIG. 4 avoids the cost of the rotary feedthrough 7.

4 shows the tube for the contact means 2 in the tube embodiment. The actual metallic contact means 2 is also tubular. It is mounted to rotate in the working container 14. Another non-rotating cooling tube 17 is located in the working container to indirectly cool the contact means 2. This tube is traversed by the refrigerant 5. Heat exchange or cold exchange from this heat pipe 17 to the tubular contact means 2 takes place. By providing a very small gap between the two tubes, very small thermal resistance of the refrigerant to the outer surface of the contact means 2 is also achieved. In order to compensate for thermal expansion and tolerance, the cooling pipe 17 is preferably connected to the refrigerant flow pipe 4 by an elastic sleeve 18 and to the refrigerant return pipe 8. In total, this is possible and facilitates assembling aspects of the present invention.

FIG. 5 shows a combination of cooled contact means 2 with or without a nearly metallized surface and chemical etching for the remaining metallization likely to occur on the rotating contact means 2. . Several contact points along the continuous flow system are shown in a side view. The metallization target surface on one side, such as the structured RFID antenna 19, is placed on an electrically nonconductive tape-shaped substrate 20. The distance between the contact means 2 in the conveying direction is preferably selected such that at least one contact means is always in electrical contact with each RFID antenna. The supply and discharge of the refrigerant through the contact means 2 is not shown in FIG. 5.

For any necessary auxiliary chemical demetallization, chemically and / or physically conditioned etchant 27 flows to the contact means 2 by means of an electrolyte supply device consisting of an etchant pump and / or a multidirectional valve. . This is done in the shield 15, which also prevents the injection of the electrolyte when the electrolyte flows at high pressure with respect to the contact means 2. A suitable opening 25 in the etchant pipe 21 and the shield 15 as a circulation element is perpendicular to the conveying direction so that the entire surface of each contacting means 2 can be reached during the rotation of the flowing electrolyte. Is placed.

Another combination for preventing unwanted metallization of the cathode contact means 2, 6 consists of cooling the contact means and cooling of the selected material or surface. In the case of certain electrolyte baths, little or no metal can be deposited on the surface, which surface itself is made of a specially selected material. If such a material is used for the contact means 2, 6 and for its surface, then these contact means and surfaces are not metallized or there are only moderate levels of metallization. At least this supports, according to the invention, the demetallization of the contact means. One example in this regard is a tin plated surface, for example, a tin plated surface on which hard chromium cannot be deposited thereon when the difference between at least the operating temperature of the electrolyte and the surface temperature of the contact means 2, 6 is large. . The same applies to the hard chromium electrolyte and the contact means, wherein the surface of the contact means is made of niobium. Surfaces coated with electrically conductive diamond behave in a similarly selective manner. Since the diamond layer also has great resistance to polishing, it is particularly suitable for the non-rotating contact means 2 according to FIGS. 1 and 2.

The printed image serves as, for example, an electrically conductive seed layer for the electroplating object structure on the electrically nonconductive substrate. The electrically conductive printer paste is printed and cured on the substrate, for example by screen printing.

However, these printed images do not have very high resistance to polishing. As a result, electrolyte reinforcement using the apparatus according to FIGS. 1 and 2, in which the printed image slides over the contact means 6, may result in the printed image being damaged in the seeding step. In this case, the plating equipment according to FIGS. 3-5 is used for short initial elongation at the start of electroplating. After the protective initial metallization of this structure, further reinforcement of the electroplating can be done using the device according to FIGS. 1 and 2. Overall, this is a very reliable and economical electroplating system, whereby the material can be produced very cost effectively.

Aspects of the present invention may also be configured as a mirror image, ie the top and bottom may be interchanged. In this case, the weight roller 16 is pressed onto the material 1. Some of the contact means 2, 6 can then also be located outside of the electrolyte 12, ie above that level the electrolyte must reach at least the anode 9. In the case of double-sided electroplating of material, the devices according to the invention are interchanged above and below the material along the transport path.

6 shows an example of a continuous flow system for a material. The material 1 is fed through the working container 14 when the stationary contact means 6 serve as a sliding or rotating conveying support. The contact means 6 is protected against the electric field of the electrolytic cell 11 by the insulation 22 up to the region of the supply line 26. The area on the surface line 26 according to the invention is protected against unwanted metallization by cooling the tubular contact means 6 and / or by the surface which is not metallized in the electrolyte used. The coolant 5 flows through the contact means 6. The insulation 22 also acts as a heat insulator.

6a shows a cross section of a continuous flow system according to the invention, with an electrolytic cell 11 arranged only in the lower region of the working container. It is formed of the material 1 and the anode 10 which are cathodes. Both electrodes are located in electrolyte 12, the level 13 of which extends to at least material 1. The cathode current supply to the material 1 takes place via the electrical conductor 23 and through the contact means 6 arranged along the conveying path.

6b shows a top view of the device according to the invention. Only a short distance in the conveying direction 24 is shown. In practice, this continuous flow system is much longer to achieve a specific throughput, for example 5 meters. The contact means 6 are arranged conically in the conveying direction to achieve an almost uniform deposition even in the contact region. Rotation of the material 1 during transport through the continuous flow system achieves a very uniform coating thickness over the entire circumference of the piston rod for the material 1, for example a shock absorber. This is also the case even when only one side of the material 1 has one anode 10 and thus also only one electrolyzer 11 as shown in the figure.

FIG. 6C shows a cross section of a very short continuous flow system along a transport path such as cross section C-D of FIG. 6A. The electrolyzer 11 is shown at the top and bottom. Thus, the deposition rate of the entire continuous flow system can be doubled. The drive required for the transfer of material 1, such as a continuous and compressible tape, corresponds to known structural knowledge and is therefore not shown in FIG.

1: material
2: rotary contact means, contact wheel, contact roller, brush contact
3: driving means
4: refrigerant flow pipe
5: refrigerant
6: fixed contact means, sliding contact, contact brush
7: rotary feed-throughs
8: refrigerant return pipe
9: sliding contact
10: anode
11: electrolytic cell
12: electrolyte
13: level
14: working container
15: shield
16: weight roller
17: cooling pipe
18: cuff
19: RFID antenna, electroplating material, material
20: substrate
21: etching liquid pipe
22: insulation
23 electric wire
24: arrow indicating the feed direction
25: opening, nozzle
26: surface line
27 etching liquid, etching electrolyte

Claims (12)

In all types of electroplating systems, a device for electrically contacting the material to be electroplated by the contact means (2, 6), wherein the contact means (2, 6), which are cathodicly polarized, extends at least partially into the electrolyte (12). And in electrical contact with the material to be electroplated, wherein at least one of the contact means (2, 6) can be cooled by a cooling device and / or a cooling medium. 2. The device according to claim 1, wherein the electrically conductive surface of the contact means (2, 6) for the purpose of electrochemical deposition of metal may be at least or little metallization in the electrolyte (12). The electrolyte supply device according to claim 1 or 2, wherein the electrolyte supply device supplies the etching liquid 27 to the contact means 2, and at least one etching liquid pump as well as the etching liquid pipe 21 having an opening or a nozzle 25 and / or Or a flow element as a multidirectional valve. A method of electrically contacting the material to be electroplated by the contact means (2, 6) in all types of electroplating systems, by means of the apparatus according to claim 1, the contact means (2, 6) being positively cathode In this method, at least partially extending into the electrolyte 12 and in electrical contact with the material to be electroplated, so that metallization of the contact means 2, 6 on the surface of the contact means is prevented in the electrolyte used. Contact means (2, 6) characterized in that the cooling medium or the cooling device can be cooled directly or indirectly. The electrochemical metallization of the contact means 2, 6 in the electrolyte 12 used is prevented by the repellent property of the material of the contact surface of the contact means 2, 6. Characterized in that the method. The method of claim 4 or 5, wherein the permanent metallization of the contact means 2 is prevented by chemically etching the surface of the contact means 2 with chemically and / or physically conditioned etchant 27. Characterized in that the method. In all types of electroplating systems, a device for electrically contacting the material to be electroplated by the contact means (2, 6), wherein the contact means (2, 6), which are cathodicly polarized, extends at least partially into the electrolyte (12). And in electrical contact with the material to be electroplated, characterized in that the material of at least the contact surface of the contact means 2, 6 in the electrolyte 12 used can be electrochemically little or no metallized. Device. Device according to claim 7, characterized in that the contact means (2, 6) can be cooled by a cooling device and / or a cooling medium. The electrolyte supply apparatus according to claim 7 or 8, wherein the electrolyte supply device supplies the etching solution 27 to the contact means 2, and has an etching solution pipe 21 and at least one etching solution pump and / or having an opening or a nozzle 25. Apparatus characterized by consisting of flow elements as multidirectional valves. A method of electrically contacting the material to be electroplated via the contact means (2, 6) in all types of electroplating systems, the contact means (2, 6) being catalyzed by the use of the device according to claim 7. In this method, at least partially extending into the electrolyte 12 and in electrical contact with the material to be electroplated, the properties of the material of the contact means 2, 6 in the electrolyte 12 used are electrochemical at its surface. Maintaining at least or little metallization. The contact means (2) and (6) of claim 10 can be cooled directly or indirectly by a cooling medium or a cooling device in order to ensure that there is little or no electrochemical metallization in the surface of the electrolyte 12 used. How it can be. 12. The permanent metallization of the contact means 2 according to claim 10 or 11 is prevented by chemically etching the surface of the contact means 2 with chemically and / or physically conditioned etchant 27. Characterized in that the method.

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