EP2010700B1 - Electroplating device and method - Google Patents

Abstract

The invention relates to a device for the electrolytic coating of at least one electrically conductive substrate or a structured or full-surface electrically conductive surface on a nonconductive substrate, which comprises at least one bath, one anode and one cathode, the bath containing an electrolyte solution containing at least one metal salt, from which metal ions are deposited on electrically conductive surfaces of the substrate to form a metal layer while the cathode is brought in contact with the substrate's surface to be coated and the substrate is transported through the bath, wherein the cathode comprises at least two disks (2, 4, 10) mounted on a respective shaft (1, 5, 14) so that they can rotate, the disks (2, 4, 10) engaging in one another. The invention furthermore relates to a method for the electrolytic coating of at least one substrate, which is carried out in a device according to the invention. Lastly, the invention also relates to a use of the device according to the invention for the electrolytic coating of electrically conductive structures on an electrically nonconductive support.

Description

The invention relates to a device for electroplating at least one electrically conductive substrate or a structured or full-surface electrically conductive surface on a non-conductive substrate, which comprises at least one bath, an anode and a cathode, wherein the bath contains an electrolyte solution containing at least one metal salt, are deposited from the metal ions on electrically conductive surfaces of the substrate to form a metal layer.

The invention further relates to a process for the galvanic coating of at least one substrate, which is carried out in a device designed according to the invention.

Galvanic coating methods are used, for example, to coat electrically conductive substrates or structured or full-area electrically conductive surfaces on non-conductive substrates. With these methods, it is possible, for example, to produce conductor tracks on printed circuit boards, RFID antennas, flat cables, thin metal foils, conductor tracks on solar cells, and to galvanically coat other products, such as two- or three-dimensional objects, for example plastic molded parts.

Out DE-B 103 42 512 For example, an apparatus and a method for the electrolytic treatment of electrically mutually insulated, electrically conductive structures on surfaces of strip-shaped material to be treated are known. Here, the material to be treated is conveyed continuously on a transport path and in a transport direction, wherein the material to be treated is contacted with a contact electrode arranged outside of an electrolysis region, whereby the electrically conductive structures are subjected to negative voltage. In the electrolysis region, metal ions are deposited on the electrically conductive structures from the treatment liquid to form a metal layer. Since only metal is deposited on the electrically conductive structures, as long as they are contacted by the contact electrode, only those structures can be coated which are dimensioned so large that the electrically conductive structure to be coated is located in the electrolysis region, while at the same time outside the Electrolysis area is contacted.

An electroplating apparatus in which the contacting unit is arranged in the electrolyte bath is, for example, in DE-A 102 34 705 disclosed. The electroplating device described here is suitable for coating already conductive structures which are arranged on a band-shaped carrier. The contacting takes place via rollers which are in contact with the conductive structures. Since the rollers are in the electrolyte bath, metal also separates out from the electrolyte bath. In order to be able to remove the metal again, the rollers are made up of individual segments which are switched cathodically, as long as they are in contact with the structures to be coated and are switched anodically, if there is no contact of roller and electrically conductive structure. Disadvantage of this arrangement, however, is that on short structures, seen in the transport direction, only a short time a voltage is applied, while seen on long structures, also in the transport direction, over a much longer period of tension. As a result, the layer which is deposited on long structures is substantially larger than the layer which is deposited on short structures.

Disadvantage of the known from the prior art method is that with these no very short structures - especially in the transport direction of the substrate - can be coated. A further disadvantage is that, in order to realize sufficiently long contact times, many rollers connected in series are required, thereby requiring a very long device.

The object of the invention is to provide a device which ensures a sufficiently long contact time even for short structures, so that even short structures are provided with a sufficiently thick and homogeneous metal layer. Furthermore, the device should require less space.

The object is achieved by a device for electroplating at least one electrically conductive substrate or a structured or full-surface electrically conductive surface on a non-conductive substrate, which comprises at least one bath, an anode and a cathode, wherein the bath is an electrolyte solution containing at least one metal salt contains, are deposited from the metal ions on electrically conductive surfaces of the substrate to form a metal layer, while the cathode is brought into contact with the surface to be coated of the substrate and the substrate is conveyed through the bath. According to the invention, the cathode comprises at least two disks rotatably mounted on a respective shaft, wherein the disks mesh with one another.

Compared to devices for electroplating, as known from the prior art, the device according to the invention with intermeshing disks as a cathode, that even substrates with short electrically conductive structures, especially in the transport direction of the substrate, with a sufficient thick and homogeneous coating can be provided. This is made possible by the fact that a smaller distance of the contact points of the discs with the electrically conductive structures can be realized by the intermeshing discs than is the case with successively arranged rollers.

The disks are designed in a cross-section matched to the respective substrate. The disks preferably have a circular cross section. The waves can have any cross section. Preferably, the waves are cylindrical.

In order to be able to coat structures that are wider than two adjacent disks, several disks are arranged next to one another on each shaft, depending on the width of the substrate. In each case, a sufficient distance is provided between the individual disks, in which the disks of the following shaft can engage. In a preferred embodiment, the distance between two disks on a shaft corresponds at least to the width of a disk. This makes it possible that in the distance between two discs on a shaft, a disc can engage another shaft.

In order to coat the regions of the electrically conductive structure on which the cathode designed as disks or disk sections rests for contacting, at least four shafts with disks can be arranged in pairs one behind the other. In this case, the arrangement is preferably such that the second pair of shafts arranged offset relative to the first pair of shafts contacts the electrically conductive structure in the region on which the metal was deposited during the contacting with the first pair of shafts. In order to achieve a greater thickness of the coating, preferably more than two pairs of waves are connected in series. Furthermore, the Einkämmabstände can be varied as desired. It is also possible to vary the distances of the individual pairs of waves as desired.

The number of juxtaposed slices on the at least one shaft is dependent on the width of the substrate. The wider the substrate to be coated, the more discs must be placed side by side. It is important to ensure that between the discs each have a free gap in which the metal can be deposited on the electrically conductive substrate or the structured or full-surface electrically conductive surface of the substrate and can comb a disk of the underlying wave.

The size of the disks used as the cathode depends on the size of the structures to be electroplated. So for example Structures whose length, viewed in the transport direction, is greater than or equal to the distance with which successive discs touch the substrate, coated sufficiently, when their width and position on the substrate is such that it also touches the offset successive roles becomes. To coat the smallest possible electrically conductive structures, therefore narrow discs are used with a small diameter. An advantage of narrow disks with small distances from one another is that the contact probability of the smallest structures is thereby greater than with a smaller number of wide disks. Since the contact surface of the disc by covering the structures directly under the disc inhibits the deposition, it is advantageous to minimize this coverage effect through narrow slices. At the same time, the electrolyte purging of the surface to be coated is more uniform by a multiplicity of smaller surface accesses than with vain surface accesses such as are present with a small number of wide disks.

The lowest possible disk width and the smallest possible diameter with which the disks can be manufactured depend, on the one hand, on the manufacturing methods available and, on the other hand, on the fact that the disk is mechanically stable during operation, i. that the disc does not buckle or bend during operation.

The distance between two intermeshing discs depends on whether the discs have the same or different polarity. For example, with the same polarity, it is possible for the intermeshing disks to touch each other, while at different polarities a distance must be provided between the disks in order to avoid a short circuit. Furthermore, sufficient flushing of the interspaces between the panes and the space delimited by the surface of the substrate to be coated with the electrolyte solution must also be ensured.

In a preferred embodiment, the discs are powered by the shaft. For this it is possible, for example, to connect the shaft outside the bath to a voltage source. This connection is generally made via a slip ring. However, any other connection is possible with which a voltage transfer from a stationary voltage source is transmitted to a rotating element. In addition to the power supply via the shaft, it is also possible to supply the contact disks on their outer circumference with power. For example, sliding contacts, such as brushes, may be in contact with the contact disks on the side facing away from the substrate.

In order to supply power to the disks, for example via the shafts, in a preferred embodiment, the shafts and the disks are at least partially made of an electrically conductive material. In addition, however, it is also possible to manufacture the shafts from an electrically insulating material and to realize the power supply to the individual disks, for example by electrical conductors, such as wires. In this case, then the individual wires are each connected to the contact discs, so that the contact discs are supplied with voltage.

If the discs are made of an electrically conductive material only at their outer periphery, then it is necessary to provide an electrical conductor which connects the shaft to the outer periphery of the disc. For this purpose, for example, an electrical conductor can be accommodated inside the pane. The power supply can also be realized via a fastening means, for example a screw, with which the disc is mounted on the shaft.

In order to realize a uniform supply of electrolyte, openings are formed in the disks in a preferred embodiment. Through the breakthroughs, the electrolyte solution can be transported to the substrate. At the same time, due to the rotation of the disks, the mixing of the electrolyte solution is improved over a closed-disk embodiment. Also, the perforated disks can deliver faster electrolyte solution to the substrate than would be possible if the electrolyte solution could only flow through the gaps between the individual disks.

Instead of apertures in solid discs, it is also possible to provide discs in which a ring with spokes is mounted on the shaft. In order to enable a galvanic coating, it is necessary that the ring is made on its outer circumference of an electrically conductive material. In a preferred embodiment, the entire ring is made of an electrically conductive material. The spokes with which the ring is fastened to the shaft can be made, for example, of an electrically conductive material or of an electrically insulating material. If the spokes are made of an electrically conductive material, it is preferred that the voltage supply of the ring via the shaft and the spokes takes place. For example, when the spokes are made of an electrically insulating material, it is possible to provide a spoke which is electrically conductive so that the voltage from the shaft can be transmitted to the ring. In addition, it is also possible for spokes made of an electrically insulating material to connect the ring via a current conductor, for example a cable to the current-carrying shaft. It is also possible with electrically insulating spokes, the voltage apply directly to the ring surface. For this purpose, the ring surface is contacted, for example, with a sliding contact, such as a brush.

In order to be able to carry out a galvanic coating of the substrate with metal ions from the electrolytic solution with the formation of a metal layer, in the abovementioned exemplary embodiments the disks are in each case connected cathodically. Due to the cathodic circuit of the discs also separates on this metal. Therefore, it is necessary to remove the disks to remove the deposited metal, i. for demetallizing, to switch anodically. This can be done, for example, in production stoppages. In order to be able to carry out a demetallization during operation, in a preferred embodiment the disks can be lifted by the substrate and lowered onto the latter. In this case, the slices lowered onto the substrate may be switched cathodically while the slices lifted from the substrate are anodically connected. Due to the cathodically connected disks, which are lowered onto the substrate, the electrically conductive structures on the substrate are cathodically contacted and thus coated. At the same time, the anodic circuit of the disks, which do not touch the substrate, removes the metal previously deposited thereon.

It is thus possible, for example, alternately to keep a wave with its disks lowered onto the substrate and to have lifted a shaft with its disks from the substrate. Preferably, however, in each case at least two successive waves are lowered with their intermeshing disks onto the substrate, in order to avoid that electrically conductive structures which are passed in a gap between two disks without cathodic contacting are not coated. As soon as two successive shafts with intermeshing disks touch the substrate, these structures, which are guided in a gap between two disks, are contacted by the following disk, which meshes with this gap. Thus, a coating of this electrically conductive structure is ensured.

In a preferred embodiment, the discs distributed over the circumference individual, electrically isolated from each other sections. The sections which are electrically insulated from one another are preferably switchable both cathodically and anodically. This makes it possible that a portion which is in contact with the substrate, is switched cathodically and as soon as it is no longer in contact with the substrate, is connected anodically. As a result, deposited metal is removed during the cathodic circuit on the portion during the anodic circuit. The voltage supply of the individual segments generally takes place via the shaft. When multiple discs are arranged side by side on a shaft These are preferably aligned so that the individual electrically isolated sections are arranged in alignment in the axial direction. This makes it possible to contact the individual, electrically isolated sections, which are in alignment in the axial direction, each with a common line. Furthermore, it is also possible to construct the shaft according to the segments of the individual disks also in individual segments which are electrically isolated from each other. In this case, then the individual segments can serve to supply power to the discs. The contacting of the shaft is preferably carried out of the bath. Contacting is possible for example by Polumwandlerscheiben or contact discs, which are brought into contact with the shaft. If individual lines are provided, with which the individual electrically isolated portions of the discs are contacted, these lines can be positioned either in the interior or on the outer circumference of the shaft.

In addition to the removal of the deposited on the shaft and the discs metal by reversing the waves are also other cleaning options, for example, a chemical or mechanical cleaning possible.

The material from which the electrically conductive parts of the disks are made is preferably an electrically conductive material which does not change into the electrolyte solution during operation of the device. Suitable materials include metals, graphite, conductive polymers such as polythiophene or metal / plastic composites. Preferred materials are stainless steel and / or titanium.

Thus, the discs do not dissolve when they are switched anodic to remove the metal deposited on it again, the usual for insoluble anodes and the skilled person known material is used for the discs and the waves. Such a suitable material is, for example, titanium coated with a conductive mixture of metal oxides.

In a further embodiment, the device for electroplating further comprises a device with which the substrate can be rotated. By rotating electrically conductive structures, which are initially seen in the transport direction of the substrate, wide and short, aligned so that they are narrow and long after turning - seen in the transport direction. By turning different coating times are compensated, which result from the fact that a coating of the electrically conductive structure already takes place with the first contact with the cathodically connected disc.

After rotation, the substrate either passes through the device a second time or a second corresponding device. The angle through which the substrate is rotated is preferably in the range of 10 ° to 170 °, more preferably in the range of 50 ° to 140 °, in particular in the range of 80 ° to 100 °, and most preferably the angle is the substrate is rotated, substantially 90 °. Essentially 90 ° means that the angle through which the substrate is rotated does not deviate more than 5 ° from 90 °. The device for rotating the substrate can be arranged inside or outside the bath. In order to further coat the same side of the substrate in order, for example, to achieve a greater layer thickness of the metal layer, the axis of rotation is oriented perpendicular to the surface to be coated.

When another surface of the substrate is to be coated, the rotation axis is arranged so that after rotation, the substrate is positioned so that the surface to be coated next faces the cathode.

The layer thickness of the metal layer deposited on the electrically conductive structure by the method according to the invention depends on the contact time, which results from the passage speed of the substrate through the device and the number of waves positioned one behind the other with intermeshing disks arranged thereon, and the current intensity with which the device is operated. A higher contact time can be achieved, for example, by connecting several devices according to the invention in series in at least one bath.

In one embodiment, a plurality of devices according to the invention are connected in series in each case in individual baths. This makes it possible to hold in each bath a different electrolyte solution to sequentially deposit different metals on the electrically conductive structures. This is advantageous, for example, in decorative applications or in the production of gold contacts. Again, the respective layer thicknesses are adjustable by the choice of the flow rate and the number of devices with the same electrolyte solution.

In order to enable a simultaneous coating of the top and bottom of the substrate, in an embodiment of the invention, two shafts each with the discs mounted thereon are arranged so that the substrate to be coated can be passed between them. According to the invention, two shafts are then provided with disks received thereon and intermeshing both on the upper side and on the lower side of the substrate. In general, the structure is then such that the plane in which the substrate is guided, as a mirror plane serves. If films are to be coated whose length exceeds the length of the bath - so-called endless films, which are initially unwound from a roll, passed through the device for electroplating and then wound up again - this can, for example, also zig-zag or in shape a meander to several inventive devices for electroplating, which can then be arranged, for example, one above the other or next to each other, are passed through the bath.

With the device according to the invention and the method according to the invention, it is furthermore possible to coat also through holes, such as holes or slots, or also depressions, such as blind holes, contained in the substrate. In the case of through holes of small depth, the coating takes place in that the metal layers deposited on the upper side and on the lower side grow together in the hole. For holes that are too deep for a coalescence of the metal layers, a conductive hole wall is at least partially provided, which is coated by the inventive method. As a result, then also the entire wall of the hole can be coated. If not the entire hole wall is electrically conductive, the coating of the entire hole wall is carried out here by growing together of the metal layers.

If only one side of the substrate is to be coated, then the substrate can either rest on the intermeshing disks, the underside of the substrate being coated or guided along the underside of the disks, coating the top of the substrate. When the substrate rests on the discs, the discs can simultaneously serve to transport the substrate. A sufficient contact of the intermeshing discs with the substrate is achieved by the fact that the substrate is preferably pressed with a pressing device to the intermeshing discs. As pressing device are, for example, pressure rollers or belts, which are guided around waves and pressed against the substrate.

When the substrate is guided along the underside of the discs, it is necessary to provide a transport device with which the substrate is brought into contact with the discs. Such a transport device is, for example, a belt or rollers on which the substrate runs. The substrate can then either be pressed by means of the device for galvanic coating with a predetermined contact force against the transport device or by means of the transport device against the device for galvanic coating.

When the substrate is simultaneously coated on its top and bottom surfaces, the intermeshing disks connected to the cathode that contact the substrate can be used simultaneously to transport the substrate through the bath.

To transport the substrate either single waves or all waves can be driven. The drive is preferably outside the bath. When a transport device independent of the cathodically connected disks is provided, the shafts and the disks mounted thereon can be rotated by the substrate, so that the peripheral speed of the disks corresponds to the speed with which the substrate is transported.

So that a uniform circumferential speed of all shafts or disks is achieved, it is preferred that all shafts are driven by a common drive unit. The drive unit is preferably an electric motor. The shafts are preferably connected to the drive unit via a chain or belt transmission. But it is also possible to provide the shafts with gears that mesh and over which the waves are driven. In addition to the possibilities described here, any further, known to those skilled, suitable drive for driving the waves can be used.

As anodes can be used on the one hand at different polarity of waves, slices or electrically isolated sections of the slices, the anodic waves, slices or electrically insulated sections of the discs, on the other hand, it is also possible to provide additional anodes in the bathroom. If only cathodically connected shafts and disks are provided, it is necessary to additionally arrange anodes in the bath. The anodes are preferably arranged as close as possible to the structure to be coated. For example, the anodes can each be arranged in front of the first and behind the last of the shafts with intermeshing disks. For example, if the substrate is only coated on one side, it is also possible to arrange the cathode on the side of the substrate on which the galvanic coating is to take place and the anode-without it touching the substrate-on the other side of the substrate , Suitable material for the anodes is on the one hand any material known to those skilled in the art for insoluble anodes. Preference is given here, for example, stainless steel, graphite, platinum, titanium or metal / plastic composites. On the other hand, soluble anodes can also be provided. These then preferably contain the metal, which is deposited galvanically on the electrically conductive structures. The anodes can take any known form to those skilled in the art. For example, flat rods can be used as anodes during operation of the device have a minimum distance to the substrate surface. It is also possible to use flat sheets or elastic wires, such as spiral wires, as anodes.

When coating a flexible circuit substrate, which is preferably in the form of a tape, this is unwound from a roll lying in front of the bath and wound after passing through the bath on a new roll.

With the device according to the invention, all electrically conductive surfaces can be coated, regardless of whether electrically insulated structures insulated from one another are to be coated on a nonconductive substrate or a full surface area. Preferably, the device is used for coating electrically conductive structures on a non-electrically conductive support, for example reinforced or unreinforced polymers, as they are commonly used for printed circuit boards, ceramic materials, glass, silicon, textiles, etc. The thus produced, electroplated electrically conductive structures are, for example, conductor tracks. The electrically conductive structures to be coated can be printed on the printed circuit board, for example, from an electrically conductive material. The electrically conductive structure preferably contains either particles of any geometry made of an electrically conductive material in a suitable matrix or consists essentially of the electrically conductive material. Suitable electrically conductive materials are, for example, carbon or graphite, metals, preferably aluminum, iron, gold, copper, nickel, silver and / or alloys or metal mixtures containing at least one of these metals, electrically conductive metal complexes, conductive organic compounds or conductive polymers.

Optionally, a pretreatment is first required to make the structures electrically conductive. This may be, for example, a chemical or a mechanical pretreatment such as a suitable cleaning. As a result, for example, the oxide layer of metals which disturbs the electroplating is removed beforehand. However, the electrically conductive structures to be coated can also be applied to the printed circuit boards by any other methods known to those skilled in the art.

Such printed circuit boards are for example installed in products such as computers, telephones, televisions, automotive electrical components, keyboards, radios, video, CD, CD-ROM and DVD players, game consoles, measuring and control devices, sensors, electrical kitchen appliances, electric toys, etc ,

Also, with the device according to the invention, electrically conductive structures can be coated on flexible circuit carriers. Such flexible circuit carriers are, for example, polymer films, such as polyimide films, PET films or polyolefin films, on which electrically conductive structures are printed. Furthermore, the device according to the invention and the method according to the invention are suitable for the production of RFID antennas, transponder antennas or other antenna forms, chip card modules, flat cables, seat heaters, foil conductors, printed conductors in solar cells or in LCD or plasma picture screens or for the production of electroplated products in any desired form , such as thin metal foils, one- or two-sided metal-clad polymer carrier with a defined layer thickness, 3D-molded interconnect devices or even for the production of decorative or functional surfaces on products that are used, for example, to shield electromagnetic radiation, for heat conduction or as packaging , Furthermore, the production of contact points or contact pads or wiring on an integrated electronic component is possible.

After leaving the device for galvanic coating, the substrate can be further processed according to all steps known to the person skilled in the art. For example, existing electrolyte residues can be removed from the substrate by rinsing and / or the substrate can be dried.

The device according to the invention for the galvanic coating of electrically conductive substrates or of electrically conductive structures on electrically non-conductive substrates can be equipped as required with any additional device known to the person skilled in the art. Such ancillary devices include, for example, pumps, filters, chemical feeders, roll-up and roll-down devices, etc.

To shorten the maintenance intervals, all methods of care of the electrolyte solution known to those skilled in the art can be used. Such care methods are, for example, systems in which the electrolyte solution regenerates itself.

The device according to the invention can, for example, also in the Werner Jillek, Gustl Keller, Manual of Printed Circuit Board Technology, Eugen G. Leuze Verlag, 2003, Volume 4, pages 192, 260, 349, 351, 352, 359 operated pulse methods are operated.

The galvanic coating device can be used for any conventional metal coating. In this case, the composition of the electrolyte solution used for the coating depends on which metal the electrically conductive structures are to be coated on the substrate. Usual metals deposited by electroplating on electrically conductive surfaces are, for example, gold, nickel, palladium, platinum, silver, tin, copper or chromium.

Suitable electrolyte solutions which can be used for the electroplating of electrically conductive structures are known to the person skilled in the art, for example Werner Jillek, Gustl Keller, Manual of Printed Circuit Board Technology, Eugen G. Leuze Verlag, 2003, Volume 4, pages 332-352 known.

The advantage of the device according to the invention and of the method according to the invention is that the intermeshing disks provide a larger contact surface and thus a longer contact time per unit area than is the case with rollers known from the prior art. As a result, shorter distances can be realized with more metal structure and more homogeneous layer thicknesses. In addition, the plants can be built shorter, enabling higher throughput and lower operating costs. Another significant advantage is that now even very short structures, as they are desired for example in the production of printed circuit boards, faster, more targeted and above all reproducible and can be realized with homogeneous layer thicknesses than with the roll systems known from the prior art is possible.

In the following the invention will be described in more detail with reference to the drawings. The figures show only one possible embodiment by way of example. Of course, except in the listed embodiments, the invention can also be implemented in further embodiments or in combination of these embodiments.

Figur 1

eine Draufsicht auf eine erfindungsgemäß ausgebildete Vorrichtung,

Figur 2

eine Seitenansicht einer erfindungsgemäß ausgebildeten Vorrichtung,

Figur 3

eine Seitenansicht einer erfindungsgemäß ausgebildeten Vorrichtung in einer zweiten Ausführungsform

Figur 4

eine Welle mit einer einzelnen darauf montierten Scheibe,

Figur 5

eine erfindungsgemäß ausgebildete Scheibe mit über den Umfang verteilten einzelnen elektrisch voneinander isolierten Abschnitten,

Figur 6

eine Kontaktscheibe zur Stromzufuhr.

Show it:

FIG. 1

a plan view of an inventively designed device,

FIG. 2

a side view of an inventive device,

FIG. 3

a side view of an inventive device in a second embodiment

FIG. 4

a shaft with a single disc mounted thereon,

FIG. 5

an inventively designed disc with distributed over the circumference of individual electrically isolated sections,

FIG. 6

a contact disc for power supply.

In FIG. 1 is a plan view of an inventively designed device shown. On a first shaft 1, a number of first discs 2 is arranged. The discs 2 are each mounted with a distance 3 on the shaft 1. The distance 3 is chosen so that can engage in these second discs 4, which are mounted on a second shaft 5. The distance 6 of the second disks 4 is chosen so that in each case between two second disks 4, a first disk 2 can engage.

In the in FIG. 1 In the illustrated embodiment, the first discs 2 mounted on the first shaft 1 and the second discs 4 mounted on the second shaft 5 are each the same width. However, it is also possible to provide discs with different widths. In this case, disks of the same width can each be provided on a shaft, while disks with a width which deviates from the width of the disks on the first shaft are provided on the second shaft, or disks of different width are mounted on a shaft. If disks of different widths are mounted on a shaft, it is necessary that the distances between two disks on the second shaft, which engage between two disks on the first shaft, be selected accordingly, that the discs of different widths can intervene in the distances.

Preferably, at least two pairs of shafts with intermeshing discs can be connected in series. The wave pairs can then be offset from each other. It is also possible that the disks of the front shaft of the rear pair meshes with the spaces between the disks of the rear shaft of the front pair.

The distance 3 between two first disks 2 is at least as great as the width of a second disk 4. Likewise, the distance 6 of the second disks 4 is at least as great as the width of a first disk 2. Preferably, the distance 3, 6 between two disks 2, 4 larger than the width of each engaging in this distance discs 2, 4, so that electrolyte solution can flow through this distance in the direction of the substrate to be coated. The engagement depth 7, with which the second disks 4 engage in the first disks 2, is dependent on the distance at which the first disks 2 and the second disks 4 are to contact the substrate. It is thus possible for the disks 2, 4 to engage with one another in the edge region or for the first disks 2 to engage between the second disks 4 so far that the first disks 2 just touch the second shaft 5. In this case, with the same diameter of the first disks 2 and the second disks 4, the second disks 4 also touch the first shaft 1. However, it is not necessary for the first disks 2 and the second disks 4 to be in the same Diameter are executed. Just as well, it is also possible that the diameters of the first disks 2 and the second disks 4 are different.

FIG. 2 shows a side view of an inventive device.

In FIG. 2 it can be seen how the first disks 2 engage in the second disks 4. The contact of the disks 2, 4 to be coated with electrically conductive structures 30 on a substrate 31 is carried out with the distance of the axial centers of the first shaft 1 and the second shaft 5. The denser the axis centers of the first shaft 1 and the second shaft 5 are together The contact points of the first disks 2 and the second disks 4 are also closer to the substrate. The distance at which the first disks 2 and the second disks 4 touch the substrate is designated by reference numeral 8.

The transport of the substrate 31 through the bath with the electrolyte solution takes place in the embodiment shown here by means of a transport device 32. In the embodiment shown here, the transport device 32 comprises an endless belt 33, which rotates two shafts 34, 35. The distance between the band 33 and the discs 2, 4 is selected so that the substrate 31 is pressed with the electrically conductive structures 30 with a defined contact force against the discs 2, 4. The pressing of the electrically conductive structures 30 to the discs 2, 4 can either be done by the transport device 32 is fixedly mounted and, for example, the discs 2, 4 is pressed with a predetermined contact force on the substrate 31 with the electrically conductive structures 30, Why the waves 1, 5 of the discs 2, 4 may be resiliently mounted. Alternatively, the axes 1, 5 of the discs 2, 4 may be fixedly mounted and predetermined contact pressure is exerted by the transport device 32 to the substrate 31. For this purpose, preferably the shafts 34, 35 of the transport device 32 are resiliently mounted. Instead of a transport device 32, as in FIG. 2 is shown, a plurality of juxtaposed individual waves can be used as a transport device. It is also possible, instead of the transport device 32, to provide a second device according to the invention which comprises at least two axles with intermeshing disks arranged thereon.

To ensure transport, either the axes 1, 5, on which the discs 2, 4 are fixed, are driven or the shafts 34, 35 with the endless belt 33. Also, it is possible, both the axes 1, 5 with to drive the discs arranged thereon 2, 4 and the shafts 34, 35. The drive of the shafts 1, 5 and 34, 35 is preferably arranged outside the bath. On the one hand, each shaft 1, 5, 34, 35 can be driven individually, the shafts 1 and 5 are preferred from a first drive and the shafts 34 and 35 driven by a second drive or all shafts 1, 5, 34, 35 are driven by a common drive. The individual shafts 1, 5 and / or 34, 35 are then connected to each other, for example via gears or chain or belt transmission.

In order that a current can flow in the electrolyte solution and thus a galvanic coating of the electrically conductive structures 30 is made possible, further anodes 36 are provided in the bath. For example, the anodes 36 may be in the form of flat bars, as shown here. Preferably, the anodes 36 are arranged in the vicinity of the electrically conductive structure 30 to be coated. In this case, care must be taken that the anodes 36 do not touch the electrically conductive structure 30, since otherwise the metal already deposited thereon would be removed again. In addition to the embodiment of the anodes 36 in the form of flat bars, the anodes 36 may also be designed as flat sheets or as elastic wires, for example spiral wires. Also, any further, known in the art form of anodes can be used. The anodes can be both insoluble and soluble.

The material for insoluble anodes 36 is known to those skilled in the art. For soluble anodes 36, the metal is preferably used, which is deposited on the electrically conductive structures 30.

FIG. 3 shows a device designed according to the invention in a further embodiment.

Unlike the in FIG. 2 illustrated embodiment, it is with the in FIG. 3 As shown, it is possible to simultaneously coat electrically conductive structures 30 on the upper side and on the underside of the substrate 31. It is also possible to galvanically coat holes 37 in the substrate and thus to obtain an electrically conductive connection of the electrically conductive structure 30 on the upper side and the electrically conductive structure 30 on the underside of the substrate 31. For this purpose, in each case a device comprising at least two shafts 1, 5 with intermeshing discs 2, 4 arranged thereon on the upper side of the substrate 31 and a device having at least two shafts 1, 5 with intermeshing discs 2, 4 arranged thereon Bottom of the substrate 31 is arranged. The substrate is passed between the devices. The transport of the substrate is preferably carried out by the discs 2, 4, which contact the electrically conductive structures 30. For this purpose, either all shafts 1, 5 on which the discs 2, 4 are arranged to be driven or only individual shafts 1, 5 are driven, while the other shafts are mounted so that they are rotated by the substrate 31 while the substrate is contacted by the disks 2, 4 on these shafts.

FIG. 4 shows a shaft formed according to the invention with a disc mounted thereon.

A slice of 10, as in FIG. 4 shown, comprises individual sections 11. The sections 11 are each electrically insulated from each other by an insulation 12. This makes it possible, for example, to switch adjacent sections 11 different. For example, a portion 11 may be cathodically connected while the adjacent portion 11 is anodically connected. The advantage of this embodiment is that metal which deposits on a portion 11 while it is cathodically connected is removed again from this portion 11 while it is connected anodically. This removal of the deposited on the individual sections 11 metal is possible during operation of the coating device. In order to be able to switch different adjacent sections 11 different, either separate section 13 for each individual disc 10 provided its own power supply 13, or because of adjacent discs 10 each of the adjacent sections 11 can be switched equal, is a continuous Power supply 13 is provided, with which each adjacent sections 11 of the adjacent discs 10 are contacted. As a power supply 13 is for example an insulated cable, which is attached to the outer circumference of the roller. Instead of the outer circumference of the shaft 14, the insulated cable can also run in the interior of the shaft 14. For this purpose, however, it is necessary that the shaft 14 is formed as a hollow shaft.

In addition to the power supply via insulated cables, power can also be supplied directly via the shaft. For this purpose, the shaft 14 in disks 10, which are constructed in individual electrically insulated sections 11, also constructed in individual electrically isolated from each other sections. The power supply can then take place in each case via the individual electrically conductive sections of the shaft 14. For this purpose, the sections 11 of the disc 10 are each connected to an electrically conductive portion of the shaft 14.

If the power supply to the individual sections 11 of the disc 10 is in each case via a power supply 13 in the form of insulated cables, the individual sections 11 are connected to the power supply 13 with cable connections 15, for example. The cable connection 15 can - as in FIG. 4 However, it is also possible, the cable connections 15, in order not to obtain lateral broadening of the discs 10, on the shaft Provide 14 facing end of the individual segments 11. This can be done for example by a spike, which is inserted into an insulated cable serving as a power supply 13.

FIG. 5 shows a side view of a disc according to FIG. 4 ,

In the embodiment shown here, the power supply of the individual segments 11 of the disc 10 via individual insulated cables, which are arranged on the outer circumference of the shaft 14. If a plurality of discs 10 are arranged side by side on the same shaft 14, openings are preferably formed in the individual segments 11 on the side facing the shaft 14, through which the cables 17 can be guided. The connection of the individual segments 11 with the cable 14 via contact connections 15th

In order to improve the supply of electrolyte to the substrate to be coated, 11 recesses 16 may be formed in the segments. In this case, the electrolyte solution can flow through the recesses 16. The recesses 16 may each be formed only in individual segments 11 of the disc 10 or in all segments 11 of the disc 10. Furthermore, it is also possible, instead of the recesses 16 in the disc 10 to make the disc 10 in the form of a wheel, in which an electrically conductive ring with individual spokes is mounted on the shaft 14. In order to enable a galvanic coating of a substrate, it is necessary that the disc 10 is electrically conductive on its outer periphery. For this purpose, it is possible, for example, to provide the disk 10 with an annular contacting area 18 which is provided on the outer circumference of the disk 10. As a material for the annular contacting region 18, for example, the known in the art, currently used for insoluble anodes conventional material is. These are, for example, titanium coated with a conductive mixture of metal oxides.

If only the annular contacting region 18 is designed to be electrically conductive, the individual segments 11 can be made of an electrically insulating material in the region between the annular contacting region 18 and the shaft 14. In this case, it is only necessary to provide either through the electrically conductive material or on the surface of the individual segments, a conductor through which the voltage from the power supply 13, which in the embodiment shown here as a cable 17, on the outer circumference Resting wave, is executed, lead to the annular contact area 18. If only the annular contacting region 18 is made electrically conductive, it is sufficient to alternately enable anodic and cathodic switching, if in each case between individual segments 19 of the annular contacting region 18, the insulation 12 is provided. Already hereby, the segments 19 of the annular contacting region 18 are sufficiently electrically insulated from one another in order to avoid a short circuit between an anodically connected segment 19 and a cathodically connected segment 19.

FIG. 6 shows an embodiment for a power supply of an inventively designed device.

The power supply to a shaft 14 with disks 10 arranged thereon can be effected, for example, via a further disk 20 arranged outside the bath with the electrolyte solution. The further disc 20 is constructed, for example, like a disc 10, with which the substrate to be coated is contacted. The further disk 20 also comprises an annular contacting region 18, which is divided into individual segments 19. Instead of an annular contacting region 18, it is also possible in each case to manufacture the individual segments 11 of the further disk 20 completely from an electrically conductive material. For mass reduction, it is also possible in the other disc 20 to provide 11 recesses 16 in the individual segments. The recesses 16 may be formed in each segment 11 or only in individual segments 11. The individual segments 19 of the annular contacting region 18 are electrically connected to the power supply 13, which in the in FIG. 6 embodiment shown also in the form of cables 17 is formed, which are arranged on the outer circumference of the shaft 14 connected.

If the entire sections 11 are made of an electrically conductive material, it is preferred that the further pane 20 is provided with electrical insulation at its end faces, so that only an electrically conductive surface is present on the outer circumference. In this way it can be avoided that injuries occur by accidental contact with the disk 20.

In order to provide voltage to the annular contacting region 18, in the embodiment shown here, a cathodic sliding contact 21 connected to a cathodic power supply 22 and an anodic sliding contact 23 connected to an anodic power supply 24 are provided. As cathodic sliding contact 21 and as anodic sliding contact 23, any sliding contact known to the person skilled in the art can be used.

If the shaft is made up of individual electrically conductive segments, which are separated by insulation, the power supply can also over Sliding contacts are made directly on the shaft. In this case, another disc 20 is not required.

In order to avoid a short circuit, respectively sufficiently large distances 25 are to be provided between the anodic sliding contact 23 and the cathodic sliding contact 21. The distance 25 between the anodic sliding contact 23 and the cathodic sliding contact 21 must be greater than the width of a segment 19. If the width of a portion 25 is less than or equal to the width of a segment 19, there will be a short circuit every time the Segment 19 simultaneously touches the cathodic sliding contact 21 and the anodic sliding contact 23.

In order to remove all of the metal again from the disks 10 which deposit thereon while being cathodically connected, the anodic contact area is preferably larger than the cathodic contact area. This means that preferably more segments are connected anodically than are connected cathodically. The maximum number of cathodically connected segments 19 corresponds to the number of anodically connected segments 19.

When running radially on the shaft 14 cables 17 is connected to the in FIG. 5 illustrated embodiment, the substrate to be coated along the underside of the discs 10 along. If the substrate is to be guided along the upper side of the disks 10, so that the underside of the substrate is coated, the cathodic sliding contact must be arranged on the upper side of the further disk 20 and the anodic sliding contact on the underside of the further disk 20.

In order to be able to coat a substrate at the same time on its upper side and its underside, it is possible to arrange two devices for galvanic coating on top of each other, wherein the substrate is passed between the devices, so that this simultaneously on its upper side and its underside of the Slices 10 is contacted.

As long as the segments, with which a cathodic contacting of the substrate takes place, are located within the electrolyte solution, the substrate can be guided along the individual devices at any angle. It is not necessary that the substrate is transported horizontally, ie parallel to the liquid surface through the bath. Thus, for example, it is even possible if the substrate to be coated is held sufficiently firmly that it is guided perpendicular to the liquid surface on the disks 10 for contacting.

LIST OF REFERENCE NUMBERS

1

first wave

2

first disc

3

Distance of the first discs

4

second disc

5

second wave

6

Distance of the second discs

7

engaging depth

8th

Distance of the touch points

10

disc

11

section

12

insulation

13

power supply

14

wave

15

cable connections

16

recess

17

electric wire

18

annular contact area

19

segment

20

another disc

21

cathodic sliding contact

22

cathodic power supply

23

anodic sliding contact

24

Anodic power supply

25

distance

30

electrically conductive structure

31

substratum

32

transport device

33

endless belt

34

waves

35

waves

36

anode

37

Hole in the substrate 31

Claims (24)

1. A device for the electrolytic coating of at least one electrically conductive substrate or a structured or full-surface electrically conductive surface on a nonconductive substrate, which comprises at least one' bath, one anode and one cathode, the bath comprising an electrolyte solution comprising at least one metal salt, from which metal ions are deposited on electrically conductive surfaces of the substrate to form a metal layer while the cathode is brought in contact with the substrate's surface to be coated and the substrate is transported through the bath, wherein the cathode comprises at least two disks (2, 4, 10) mounted on a respective shaft (1, 5, 14) so that they can rotate, the disks (2, 4, 10) engaging in one another.
2. The device according to claim 1, wherein a plurality of disks (2, 4, 10) are arranged next to one another on each shaft (1, 5, 14).
3. The device according to claim 2, wherein the distance between two disks (2, 4, 10) on a shaft (1, 5, 14) corresponds at least to the width of a disk (2, 4, 10).
4. The device according to one of claims 1 to 3, wherein the disks (2, 4, 10) are supplied with voltage via the shaft (1, 5, 14).
5. The device according to claim 4, wherein the shaft (1, 5, 14) and the disks (2, 4, 10) are made at least partly of an electrically conductive material which does not pass into the electrolyte solution during operation of the device.
6. The device according to one of claims 1 to 5, wherein recesses (16) are formed in the disks (2, 4, 10).
7. The device according to claim 6, wherein the disk (2, 4, 10) comprises a ring which is fastened on the axle by spokes.
8. The device according to one of claims 1 to 7, wherein the disk (2, 4, 10) has individual sections (11), electrically insulated from one another, distributed over the circumference.
9. The device according to claim 8, wherein the sections (11) electrically insulated from one another can be connected both cathodically and anodically.
10. The device according to claim 8 or 9, wherein the shafts (1, 5) are constructed from a plurality of electrically conductive segments which are respectively separated from one another by nonconductive segments, the electrically conductive segments being connectable both cathodically and anodically and the conductive segments of the shaft respectively contacting an electrically conductive section (11) of a disk.
11. The device according to one of claims 1 to 10, wherein the disks (2, 4, 10) can be raised from the substrate (31) and lowered onto it.
12. The device according to one of claims 1 to 11, wherein the device furthermore comprises a device with which the substrate (31) can be rotated, the device being arrangeable inside or outside the bath.
13. The device according to one of claims 1 to 12, wherein two devices, respectively having at least two shafts (1, 5) with inter-engaged disks (2, 4, 10) arranged thereon, are arranged opposite each other so that the substrate (31) to be coated is passed through between them and at least two shafts (1, 5), with inter-engaged disks (2, 4, 10) arranged thereon, respectively contact the upper side and the lower side of the substrate (31).
14. The device according to one of claims 1 to 13, wherein in order to coat flexible supports which are unwound from a first roll and wound onto a second roll, a plurality of devices, respectively having at least two shafts (1, 5) with inter-engaged disks (2, 4, 10) arranged thereon, are arranged above one another or next to one another, the flexible support passing through the devices in a meandering fashion.
15. A device for the electrolytic coating of at least one electrically conductive substrate or a structured or full-surface electrically conductive surface on a nonconductive substrate, which device comprises a plurality of devices according to one of claims 1 to 14, which are connected in series.
16. A method for the electrolytic coating of electrically conductive substrates or structured or full-surface electrically conductive surfaces on a nonconductive substrate, which is carried out in a device according to one of claims 1 to 15.
17. The method according to claim 16, wherein disks which touch the substrate are connected cathodically and disks which are not in contact with the substrate can be connected anodically.
18. The method according to claim 16, wherein sections of the disks which are in contact with the substrate are connected cathodically and sections of the disks which are not in contact with the substrate can be connected anodically.
19. The method according to one of claims 16 to 18, wherein the disks are supplied with voltage via the shafts.
20. The method according to claim 16 or 17, wherein the shafts are connected anodically for demetallization during a production pause.
21. Use of the device according to one of claims 1 to 15 for the electrolytic coating of electrically conductive substrates or structured or full-surface electrically conductive surfaces on a nonconductive substrate.
22. Use of the device according to one of claims 1 to 15 for the production of conductor tracks on printed circuit boards, RFID antennas, transponder antennas or other antenna structures, chip card modules, flat cables, seat heaters, foil conductors, conductor tracks in solar cells or in LCD/plasma display screens or for the production of electrolytically coated products in any form.
23. Use of the device according to one of claims 1 to 15 for the production of decorative or functional surfaces on products which are used for shielding electromagnetic radiation, for thermal conduction or as packaging.
24. Use of the device according to one of claims 1 to 15 for the production of thin metal foils or polymer supports clad with metal on one or two sides.

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