EP4385285A1

EP4385285A1 - Method for contacting an electrically conductive paper structure, composite body and use

Info

Publication number: EP4385285A1
Application number: EP22762029.1A
Authority: EP
Inventors: Daniel Lenssen; Mario R. Keller; Stefan Schusser; Stephan Schunck; Martin Staiger; Michael Pfeifer; Marco Sauler
Original assignee: Giesecke and Devrient Currency Technology GmbH; Surteco GmbH
Current assignee: Giesecke and Devrient Currency Technology GmbH; Surteco GmbH
Priority date: 2021-08-09
Filing date: 2022-08-05
Publication date: 2024-06-19
Also published as: WO2023016945A1; DE102021120697A1

Abstract

The invention relates to a composite body, comprising: a support plate (1) having recesses, an upper main surface and a lower main surface; and an electrically conductive paper structure (4) adjoining the upper main surface of the support plate, wherein: the electrically conductive paper structure (4) has at least one conductor track (3) facing the upper main surface of the support plate; and conductor elements (2) are introduced into the recesses of the support plate such that the conductor elements (2) terminate flush with the upper main surface of the support plate (1), the conductor elements (2) are in electrical contact with the at least one conductor track (3) of the electrically conductive paper structure (4), and the conductor elements (2) are contactable with a current source from the lower main surface of the support plate (1).

Description

Process for contacting an electrically conductive paper structure, composite body and use

The invention relates to a method for contacting an electrically conductive paper structure. The invention also relates to a composite body and a use of the same.

The uniform, large-area heating of certain components is advantageous in many areas. With regard to the cold walls in an airplane or a motor vehicle with possible home furnishings, it is expedient to introduce heating energy into the system via a blower in order to create a pleasant room climate in this way. The introduction of heating energy occurs, for example, in motor vehicles with possible home furnishings, usually via pipe systems that are operated electrically or with fossil fuels, require a high level of installation effort and are used at correspondingly high costs. It is difficult to heat large areas and the formation of condensation cannot be completely avoided.

In contrast, heated surfaces are a fast and usually more energy-saving alternative in terms of heat input. In addition, the heated surfaces inside a motor vehicle with possible home furnishings help to avoid condensation. Heatable paper or paper-like materials are particularly suitable for this, among other things due to the on-board voltage used. It is known that paper can be made conductive by introducing conductive particles in the course of paper production, see for example the documents US Pat. No. 4,990,755 A, JP H-05 135 774 A and EP 1 063716 A2. By a suitable application of conductor tracks, in particular busbars or conductor rails, for example by providing metallic ones The current can be effectively coupled into tapes, by printing, coating or vaporizing with conductive materials or the like and thus distributing it over the entire surface.

Conductive paper is particularly suitable for heating laminated panels because it can be impregnated and used without major process changes during the production of decorative laminated panels. Other surface heating systems, which are described, for example, in EP 3 691408 A1 or EP 3544 372 A1, can only be applied through additional process steps and remain visible. As a rule, such a provision is only possible via additional components that have to be applied independently of the plate production. The disadvantages here are of course the costs and the additional work involved, but also optical limitations and possible limitations with moving parts. Printed, coated or vapour-deposited conductor tracks are particularly advantageous when heating with conductive paper because they do not represent a major barrier during impregnation and can no longer be seen in the finished decorative panel. One challenge is to expose and contact the laminated conductor tracks again. The contacting should be as variable as possible with regard to the positioning of the contact points, so that heating surfaces of different sizes can be assembled easily. In addition, the connection problem, especially with regard to moving parts, e.g. doors, must be taken into account.

The object of the present invention is to overcome the disadvantages of the prior art and to provide an improved composite body and an improved method for contacting an electrically conductive paper structure. The composite body should in particular be optically indistinguishable from the usual standard plates and have an additional function, preferably heatability.

The object is achieved by the combinations of features defined in the independent claims. Developments of the invention are the subject matter of the dependent claims.

Summary of the Invention

1. (First aspect of the invention) Composite body, comprising a carrier plate having recesses with an upper major surface and a lower major face and an electrically conductive paper structure adjoining the upper major face of the carrier plate, wherein the electrically conductive paper structure has at least one conductor track facing the upper major face of the carrier plate wherein conductor elements are introduced into the recesses of the carrier plate in such a way that the conductor elements end flush with the upper main surface of the carrier plate, the conductor elements are in electrical contact with the at least one conductor track of the electrically conductive paper structure and the conductor elements are in electrical contact from the lower main surface of the carrier plate can be contacted with a power source.

2. (Preferred embodiment) Composite body according to clause 1, wherein the electrically conductive paper structure has at least two conductor tracks facing the upper main surface of the carrier plate, conductor elements being introduced into the recesses of the carrier plate in such a way that the conductor elements end flush with the upper main surface of the carrier plate, the conductor elements are in electrical contact with the at least two conductor tracks of the electrically conductive paper structure and the conductor elements can be contacted with a power source from the lower main surface of the carrier plate.

3. (Preferred embodiment) Composite body according to clause 1 or 2, wherein the recesses of the carrier plate are in the form of bores and the conductor elements introduced into the bores are in the form of bolts, screws or countersunk rivets.

4. (Preferred embodiment) Composite body according to clause 1 or 2, wherein the recesses of the carrier plate are in the form of linear indentations, preferably milling lines, and the conductor elements introduced into the linear indentations are in the form of metal strips or metal rails, the in the form of linear Depressions present recesses optionally each have an additional bore, which is adapted to the fact that the respective introduced into the linear depression conductor element can be contacted from the lower main surface of the support plate with a power source.

5. (Preferred embodiment) Composite body according to Clause 1 or 2, wherein the recesses of the carrier plate are each in the form of a combination of a bore and a linear depression, preferably a milling line, with the bore being formed in the region of the linear depression and the conductor elements T-shaped in the form of a section introduced into the linear depression and at least one section arranged perpendicular thereto and introduced into the bore.

6. (Preferred embodiment) Composite body according to one of clauses 1 to 5, wherein the contacting of the conductor elements from the lower main surface of the carrier plate with a power source by means of a connector o which takes place by means of a screw in connection with a cable lug, the respective conductor element preferably having a bore or an internal thread.

7. (Preferred embodiment) Composite body according to any one of clauses 1 to

6, wherein the electrically conductive paper structure has a decorative layer on the side opposite the carrier plate.

8. (Preferred embodiment) Composite body according to any one of clauses 1 to

7, wherein the carrier plate is a composite material, e.g. chipboard, plywood, medium-density (wood) fiber board or MDF board, coarse chipboard or OSB board or a plastic-based, in particular thermoplastic, carrier board.

9. (Preferred embodiment) Composite body according to any one of clauses 1 to

8, wherein the electrically conductive paper structure is based on cellulosic fibrous materials and electrically conductive fibers.

10. (Second aspect of the invention) Use of the composite body according to one of clauses 1 to 9 as a heating element, as an element for electromagnetic shielding, as an element for supplying other electrical consumers such as LEDs, as an element for dissipating electrostatic charges or as an element for signal transmission or signal detection.

11. (Third aspect of the invention) A method for contacting an electrically conductive paper structure with a power source, comprising

- the step of providing an apertured backing plate having an upper major surface and a lower major surface; - the step of introducing conductor elements into the recesses of the carrier plate in such a way that the conductor elements are flush with the upper main surface of the carrier plate,

- the step of providing an electrically conductive paper structure which has at least one conductor track, preferably at least two conductor tracks, on a main surface;

- the step of assembling the carrier plate and the electrically conductive paper structure to form a composite body in such a way that the electrically conductive paper structure is adjacent to the upper main surface of the carrier plate, the conductor elements of the carrier plate with the at least one conductor track, preferably with the at least two conductor tracks, of the electrically conductive paper structure are in electrical contact and the conductor elements of the carrier plate can be contacted from the lower main surface of the carrier plate with a power source; and

- the step of contacting the conductor elements of the carrier board from the lower major surface of the carrier board with a power source.

12. (Preferred embodiment) The method of clause 11, wherein the composite is as defined in any one of clauses 1-9.

Detailed Description of Preferred Embodiments

Conventional surface heating systems can only be applied through complex process steps and remain visible, which leads to a lot of work and high costs, limitations in moving parts and visual limitations. The present invention is based on the use of an electrically conductive paper structure within a composite body for heating applications. Similar to decorative paper can the electrically conductive paper structure can be introduced without additional effort as part of the usual production of composite bodies, in particular composite panels. The major challenge is the safe electrical contacting of a conductive layer embedded in an impregnating resin. The present invention ensures a simple, safe and permanent electrical and mechanical contacting of the conductive layer in rigid and movable built-in parts. Compared to the state of the art, the use of the composite body according to the invention, for example in a motor vehicle with possible home furnishings, results in a significant weight advantage and also a gain in space due to the compact design. In the course of the production of the composite body according to the invention, a carrier plate is provided with recesses. The recesses are in particular in the form of linear indentations which are, for example, continuous or interrupted, preferably milling lines, and/or in the form of (in particular punctiform) bores, drilled holes, through-holes or perforations. The recesses are filled with conductor elements, ie electrically conductive elements or contact elements, so that the conductor elements are flush with the carrier plate on the side on which the electrically conductive paper structure is laminated. The conductor elements can in particular be present in the form of metal bands, metal rails, metal strips, metal bolts, screws or contact rivets or countersunk rivets. With respect to the metal, copper or zinc is preferred, with copper being particularly preferred. At least two parallel conductor tracks are expediently applied to the electrically conductive paper structure, which distribute the current along the conductor elements. The conductor elements are placed in such a way that they can be connected to the conductor tracks of the electrically conductive paper structure are in electrical contact and can also be contacted in the finished composite body.

According to the present invention, it is basically sufficient if only one conductor track is applied to the electrically conductive paper structure. In the description below, the invention is described on the basis of particular embodiments in which at least two parallel conductor tracks are applied to the electrically conductive paper structure.

As can be seen from the appended FIG. 1, the support plate for receiving the conductor elements is expediently prepared by drilling and/or by milling in the area of the side which later comes into contact with the electrically conductive paper structure. The maximum number and size of the recesses, in particular bores and/or milling lines, is advantageously chosen such that the stability of the carrier plate is maintained. The conductor elements, e.g. (copper) countersunk rivets, bolts or (thread-cutting) screws, are inserted precisely into the recesses. The ladder element must be flush with the carrier plate. The recesses, e.g. holes, run parallel to the at least two conductor tracks of the electrically conductive paper structure on the side of the carrier plate to be coated with the electrically conductive paper structure.

The electrically conductive paper structure provided with the conductor tracks, e.g. metal strips such as copper or zinc strips, is applied to the carrier plate provided with the conductor elements, e.g. by lamination, laminating, gluing or pressing, so that the conductor tracks and the conductor elements are in permanent current-carrying contact with one another . At- subsequently, or possibly at the same time, the decorative layer is applied. A decorative paper or a decorative (finish) foil is suitable as a decorative layer, the decorative layer possibly being impregnated, printed or lacquered. With regard to the carrier board, a composite material is suitable, for example chipboard, plywood, medium-density (wood) fiber board or MDF board, coarse chipboard or OSB board or a plastic-based, in particular thermoplastic, carrier board. If the recesses in the support plate are in the form of drilled holes (Variant 1), (copper) countersunk rivets that are inserted in the drilled holes in the support plate are preferably suitable as conductor elements. The respective (copper) countersunk rivet can in particular be provided with a thread or a drilled hole on the back. The diameter of the drilled hole in the carrier plate is expediently greater than or equal to the pin diameter of the (copper) countersunk rivet. Furthermore, the length of the (copper) strands is advantageously smaller than the thickness of the carrier plate. The respective hole can be produced, for example, by means of drilling, but also by means of laser perforation or by means of cutting, for example by means of laser cutting. If the recesses in the carrier plate are in the form of linear indentations, eg milling lines (variant 2), the production of the composite body proceeds analogously to the explanation above. Accordingly, the carrier plate is prepared for receiving the conductor elements, for example by means of milling. The milling line is expediently inserted so deep into the material that the stability of the carrier plate is maintained. The conductor elements, for example metal rails, metal strips such as copper strips or the like, are inserted into the milling lines or grooves with a precise fit. The respective ladder element must be flush with the carrier plate. The milling lines run on the electrically conductive pa- pier structure to be coated side of the carrier plate precisely parallel to the at least two conductor tracks of the electrically conductive paper structure. The conductor elements, in particular metal strips such as copper strips or the like, are expediently sufficiently thick and sufficiently mechanically stable so that the carrier plate is not damaged during the subsequent steps in the course of lamination or pressing. The electrically conductive paper structure provided with the conductor tracks, eg copper strips, is applied to the carrier plate provided with the conductor elements, for example by lamination, laminating, gluing or pressing, so that the conductor tracks and the conductor elements are permanently in current-carrying contact with one another. Subsequently, or possibly at the same time, the decorative layer is applied. This is followed by the exposure of the conductor elements, with a drill hole being drilled on the rear side, preferably at any desired location, with a precise fit parallel to the respective milling line. In the case of a metal rail as the conductor element, the metal rail acts as an attachment point and prevents piercing or visible defects on the decorative side.

An alternative configuration is based on a combination of a linear indentation, in particular a milling line, and a bore (variant 3). In this case, the carrier plate is prepared for receiving the conductor elements both by providing a linear indentation, in particular a milling line, and by providing bores. The linear indentations penetrate so deeply into the material that the support plate remains stable. In addition, the maximum number and size of the bores are expediently selected such that the support plate and the conductor element remain stable. The conductor elements, for example metal rails such as copper rails, are introduced into a groove (herein also referred to as an elongate indentation or elongate indentation) with a precise fit at defined intervals. advance will the metal rail, in particular a copper rail, is provided with threaded welding studs, for example. The carrier plate has bores that are arranged to match the threaded welding studs. The diameter of the bores is expediently larger than the nominal diameter of the bolts and the depth of the bores is advantageously longer than the length of the bolts in order to avert manufacturing tolerances and material stresses. The ladder element must be flush with the carrier plate. The linear indentations, in particular milling lines, run on the side of the carrier plate to be coated with the electrically conductive paper structure in a precisely parallel manner with the conductor tracks of the electrically conductive paper structure to be applied in a further process step. The electrically conductive paper structure provided with the conductor tracks, for example copper strips, is applied to the carrier plate provided with the conductor elements, for example by lamination, laminating, gluing or pressing, so that the conductor tracks and the conductor elements are in electrical contact with one another. Subsequently, or possibly at the same time, the decorative layer is applied.

In all three variants, the conductor elements are contacted with a power source, for example, by means of connectors such as banana plugs or similar, possibly self-locking connectors, preferably in conjunction with (copper) countersunk rivets as conductor elements. In the case of a (copper) countersunk rivet with an internal thread as the conductor element, contacting by means of a cylinder head screw or comparable types of screws is advisable. In the event that the conductor element is provided by a screw with a bore or by a threaded welding stud, the contacting can expediently take place by means of a thread-forming screw, if necessary. If necessary, all types of contact can be made in conjunction with cable lugs and washers. Another option for rear contacting is based on connecting the (copper) countersunk rivet and the rear connection cable using a conductive adhesive or a soldered connection with a suitable soldering compound.

The advantages that are achieved on the basis of the plane-parallel surface of the carrier plate, which is flush with the conductor element, are the low additional effort during installation, the low visual visibility of additional components and the possibility of connecting several elements in series, resulting in reduced wiring effort. Compared to the prior art, there is also a weight saving. Furthermore, the use of non-fossil energy sources for heating is possible.

Special advantages of variant 1 described above are also:

- The processability of the composite body, which is guaranteed almost everywhere without restrictions, in particular the ability to be cut to size;

- the pre-assembled contact, so to speak, and thus the immediate ability to make electrical, current-carrying contacts, i.e. access to the rear is already available, so that no additional drilling is necessary;

- avoiding the risk of perforating the decorative layer, e.g. through careless drilling;

- the high degree of freedom regarding the use of alternative designs, e.g. elements with turns, soldered connections or glued connections.

Special advantages of variant 2 described above are also:

- The increased current-carrying capacity in view of the increased cross-section, because electricity is partially or possibly primarily via metal rails or metal strips can be transported; thus, the provision of even a smaller wiring layer on the electroconductive paper texture becomes possible;

- the metal rail or the metal strip can be contacted at any point, regardless of its position, e.g. from behind (e.g. by simply drilling a hole up to the metal rail).

Special advantages of variant 3 described above are also:

- the pre-assembled contact, so to speak, and thus immediate electrical, current-carrying contactability, i.e. access to the rear is already available and therefore no additional drilling is necessary;

- The increased current-carrying capacity in view of the increased cross-section, because electricity can be transported partially or possibly primarily via metal rails or metal strips; thus even a smaller conductor track layer can be provided on the electrically conductive paper structure;

- if conductor elements are equipped with bores (possibly with internal threads), there is an additional advantage that there is no risk of perforating the decorative layer, e.g. through careless drilling;

- if ladder elements are equipped with threaded welding studs (with internal or external threads), there is no risk of perforation or damage to the decorative layer, e.g. due to screws that are too long.

The electrically conductive paper structure can be produced using standard papermaking methods, in particular inclined wire, Fourdrinier wire and cylinder wire technology. In this way it is basically possible to process varying fiber compositions. It is expedient to add conductive, metallic short-cut fibers to cellulose-containing or alternatively plastic-based fibrous materials. The metallic short cut fibers typically have a fiber length in the range of 3 to 12 mm. The amount in which the conductive, metallic short-cut fibers are added are mixed is expediently chosen so that there are sufficient fiber-to-fiber contacts and thus a suitable electric current flow is ensured. The electrically conductive paper structure can contain other natural and/or synthetic fibers, optionally chemical additives and optionally residual moisture. Furthermore, the electrical conductivity can be achieved not only by conductive, metallic fibers, in particular metallic short-cut fibers, but also by adding carbon fibers, carbon particles or carbon nanotubes. Alternatively, conductivity can be achieved with a conductive surface coating. Furthermore, the term (paper) structure also includes other woven fabrics, nonwoven fabrics or the like, in particular foil-based conductive materials.

Further exemplary embodiments and advantages of the invention are explained below with reference to the figures, in which a reproduction true to scale and proportions was dispensed with in order to increase clarity.

Show it:

FIGS. 1 and 2 show a first exemplary embodiment of a composite body according to the invention;

FIGS. 3 and 4 show a second exemplary embodiment of a composite body according to the invention;

FIGS. 5 and 6 show a third exemplary embodiment of a composite body according to the invention; FIGS. 7 and 8 show a fourth exemplary embodiment of a composite body according to the invention;

FIGS. 9 and 10 show a fifth exemplary embodiment of a composite body according to the invention;

FIGS. 11 and 12 show a sixth exemplary embodiment of a composite body according to the invention;

FIG. 13 shows a seventh exemplary embodiment of a composite body according to the invention; and

FIG. 14 shows an eighth exemplary embodiment of a composite body according to the invention.

FIGS. 1 and 2 illustrate a first exemplary embodiment of a composite body according to the invention. According to FIG. 1, a carrier plate 1, in the example a chipboard, is first provided. The support plate is provided with continuous, circular bores 2, each having the diameter A. The bores 2 are then provided with conductor elements 2, in the example electrically conductive bolts, the conductor elements 2 terminating flush with the carrier plate 1 on their upper side and being able to be contacted on their lower side in the finished composite body. In the next step, an electrically conductive paper structure 4, which is provided with conductor tracks 3, eg copper strips, is laminated on. Lamination takes place in such a way that the conductor tracks 3 and the conductor elements 2 are in electrical contact with one another. In addition, a decorative layer 5, in the example a decorative paper, is provided. FIG. 2 illustrates the composite body shown in FIG. 1 in an oblique view. The cross-sectional view according to FIG. 1 runs along the dashed line ZZ′ shown in FIG.

FIGS. 3 and 4 illustrate a second exemplary embodiment of a composite body according to the invention, which is based on the first exemplary embodiment. FIGS. 3 and 4 each show a cross-sectional view along the dashed line Z-Z′ shown in FIG. 2. In contrast to the first exemplary embodiment shown in FIGS in such a way that the bores are suitable for countersunk rivets, in particular countersunk rivets according to DIN 661. According to FIG. 3, the continuous bores have a head diameter C and a shank diameter B. FIG. 4 illustrates the carrier plate 1 provided with (copper) rivets 21 as conductor elements. The increased head diameter C of the (copper) rivets 21 ensures simplified assembly to ensure that the (copper) rivets 21 are flush with the carrier plate 1.

FIGS. 5 and 6 illustrate a third exemplary embodiment of a composite body according to the invention, which is based on the second exemplary embodiment. FIGS. 5 and 6 each show a cross-sectional view along the dashed line Z-Z′ shown in FIG. In the present case, too, (copper) countersunk rivets are used as conductor elements. Compared to the second exemplary embodiment, the (copper) countersunk rivets 22 introduced into the carrier plate 1 have a bore 221 (see FIG. 5). According to FIG. 6, the bore 221 serves to improve th rear contact with, for example, a connector 6, in this example, a banana plug.

FIGS. 7 and 8 illustrate a fourth exemplary embodiment of a composite body according to the invention, which is based on the first exemplary embodiment. In the present case, too, (copper) rivets 23 are used as conductor elements. The length of the (copper) countersunk rivets 23 is identical to the thickness of the carrier plate 1 in the present exemplary embodiment. In addition, the (copper) countersunk rivets 23 have an internal thread 231 (see FIG. 7). According to Figure 7, the internal thread 231 of the countersunk rivet 23 serves as rear contact by means of a threaded screw 9. In the present example, the electrical connection is made according to Figure 8 by means of a cable lug 10 and by means of washers 7 and 8, the thickness, outer and inner diameter of which corresponds to the mechanical one and electrical conditions are adjusted.

The first to fourth exemplary embodiments each fall under variant 1 explained in the above description, according to which bores introduced at points in the support plate are used for receiving cylindrical conductor elements such as bolts or countersunk rivets.

FIGS. 9 and 10 illustrate a fifth exemplary embodiment of a composite body according to the invention, which falls under variant 2 explained in the above description. A linear indentation introduced into the carrier plate 1, in particular a milled line, serves to accommodate a metal strip (in particular a copper strip) or a metal rail (in particular a copper rail) as conductor element 11 (see FIG. 9). FIG. 10 shows a cross-sectional view of the carrier plate 1 along the dotted line Z-Z' shown in FIG. Based on It can be seen from FIG. 10 that in order to establish the contact on the underside of the conductor element 11, the underside of the conductor element 11 is exposed from below, e.g. by means of drilled holes 112 on the rear that are carried out with a precise fit at any point parallel to the linear depression.

The conductor elements 11 shown in FIGS. 9 and 10 terminate flush with the carrier plate 1 on their upper side and can be electrically and current-carrying contacted on their lower side in the finished composite body. Analogously to the previous exemplary embodiments, an electrically conductive paper structure 4, which is provided with conductor tracks 3, e.g. copper strips, is laminated on in subsequent steps. Lamination takes place in such a way that the conductor tracks 3 and the conductor elements 11 are in contact with one another. Finally, a decorative layer 5 is applied, in the example a decorative paper.

FIGS. 11 and 12 illustrate a sixth exemplary embodiment of a composite body according to the invention, which falls under variant 3 explained in the above description. According to FIG. 11, the support plate 1 is prepared for receiving T-shaped conductor elements 12 both by milling and by providing bores. FIG. 12 is a cross-sectional view taken along the dotted line ZZ' of FIG. The T-shaped conductor elements have a rail-shaped section 121 and a cylindrical section 122 perpendicular thereto. Threaded welding bolts are expediently welded onto the metal rails to produce the conductor elements. The carrier plate 1 has bores which are arranged to match the threaded welding bolts 122 . The diameter of the bores is expediently larger than the nominal diameter of the bolts 122 and the depth of the bores is advantageously longer than the length of the bolts 122 in order to avoid manufacturing tolerances. and avert material stresses. The conductor element 12 ends flush with the carrier plate 1 . The linear indentations, in particular milling lines, run on the side of the carrier plate 1 to be coated with the electrically conductive paper structure 4 with an exact fit parallel to the conductor tracks 3 of the electrically conductive paper structure 4 to be applied in a further process step the conductor tracks 3, for example copper strips, provided electrically conductive paper structure 4 is applied, in the example by lamination, so that the conductor tracks 3 and the conductor elements 12 are in electrical, current-carrying contact with one another. The decorative layer 5 is then applied.

FIG. 13 illustrates a seventh exemplary embodiment of a composite body according to the invention, which is based on the first exemplary embodiment described with reference to FIGS. According to FIG. 13, the electrically conductive paper structure 4 is provided with conductor tracks 3, e.g.

FIG. 14 illustrates an eighth exemplary embodiment of a composite body according to the invention, which is based on the first exemplary embodiment described with reference to FIGS. According to FIG. 14, the electrically conductive paper structure 4 is provided with conductor tracks 3, for example copper strips, in such a way that the conductor tracks 3 are completely embedded in the paper structure 4. The conductor elements 24 have needle-shaped extensions 241 on their upper side, via which the conductor tracks 3 and the conductor elements 24 are in electrical contact with one another. According to a ninth exemplary embodiment, not shown in the drawing, which occupies an intermediate position between the two seventh and eighth exemplary embodiments illustrated in FIGS Paper structure 4 is completely embedded (see the embedding shown in Figure 14) and is embedded in certain areas of the electrically conductive paper structure 4 in such a way that the conductor track 3 is freely accessible from one side and can be electrically contacted with the conductor element 2 (see the Embedding shown in Figure 13). The partially exposed conductor track 3 described in the ninth embodiment is similar to a window security thread known in the technical field of banknotes, which is completely embedded in the paper in certain areas and emerges on the surface of the paper in certain window areas. For example, FIG. 1 of EP 3 034 315 A1 shows a bank note with a window security thread. The production can take place, for example, by means of a cylinder mold paper machine. Alternatively, the partially exposed areas can be created, for example, by removing the paper in the window areas.

In the above exemplary embodiments, two conductor tracks 3 are applied to the electrically conductive paper structure 4 . According to the present invention, it is basically sufficient if only one conductor track 3 is applied to the electrically conductive paper structure 4 .

Furthermore, the preceding exemplary embodiments can be combined with one another. For example, the conductor element 11 shown in FIG. 10 can be provided in the areas 112 with the threaded welding studs 122 shown in FIG To form the shape of two interconnected T-shaped ladder elements.

Claims

22Claims

1. Composite body, comprising a carrier plate having cutouts with an upper major surface and a lower major face and an electrically conductive paper structure adjoining the upper major face of the carrier plate, wherein the electrically conductive paper structure has at least one conductor track facing the upper major face of the carrier plate, wherein in the cutouts conductor elements are introduced into the carrier plate in such a way that the conductor elements end flush with the upper main surface of the carrier plate, the conductor elements are in electrical contact with the at least one conductor track of the electrically conductive paper structure and the conductor elements can be contacted with a power source from the lower main surface of the carrier plate.

2. Composite body according to claim 1, wherein the electrically conductive paper structure has at least two conductor tracks facing the upper main surface of the carrier plate, conductor elements being introduced into the recesses of the carrier plate in such a way that the conductor elements end flush with the upper main surface of the carrier plate, the conductor elements with the at least two conductor tracks of the electrically conductive paper structure are in electrical contact and the conductor elements can be contacted with a power source from the lower main surface of the carrier plate.

3. Composite body according to claim 1 or 2, wherein the recesses of the carrier plate are in the form of bores and the conductor elements introduced into the bores are in the form of bolts, screws or countersunk rivets.

4. The composite body according to claim 1 or 2, wherein the recesses in the carrier plate are in the form of linear depressions, preferably milling lines, and the conductor elements introduced into the linear depressions are in the form of metal strips or metal rails, the recesses being in the form of linear depressions optionally each have an additional bore, which is adapted so that the respective conductor element introduced into the linear depression can be contacted with a power source from the lower main surface of the carrier plate.

5. Composite body according to claim 1 or 2, wherein the recesses of the carrier plate are each in the form of a combination of a bore and a linear indentation, preferably a milled line, with the bore being formed in the region of the linear indentation and the conductor elements being T-shaped in The form of a section introduced into the linear depression and at least one section arranged perpendicular thereto and introduced into the bore.

6. Composite body according to one of claims 1 to 5, wherein the conductor elements are contacted from the lower main surface of the carrier plate with a power source by means of a plug connector or by means of a screw in connection with a cable lug, the respective conductor element preferably having a bore or an internal thread having.

7. Composite body according to one of claims 1 to 6, wherein the electrically conductive paper structure has a decorative layer on the side opposite the carrier plate.

8. Composite body according to one of claims 1 to 7, wherein the carrier board is a composite material, e.g. carrier plate is.

9. Composite body according to one of claims 1 to 8, wherein the electrically conductive paper structure is based on cellulose-containing fibrous materials and electrically conductive fibers.

10. Use of the composite body according to one of claims 1 to 9 as a heating element, as an element for electromagnetic shielding, as an element for supplying other electrical consumers such as LEDs, as an element for dissipating electrostatic charges or as an element for signal transmission or signal detection.

11. A method for contacting an electrically conductive paper structure with a power source, comprising

- the step of providing an apertured backing plate having an upper major surface and a lower major surface;

- the step of introducing conductor elements into the recesses of the carrier plate in such a way that the conductor elements are flush with the upper main surface of the carrier plate,

- The step of assembling the carrier plate and the electrically conductive paper structure to form a composite body in such a way that the electrically conductive paper structure is adjacent to the upper main surface of the carrier plate, the conductor elements of the carrier plate with the at least one conductor 25 terbahn, preferably with the at least two conductor tracks, of the electrically conductive paper structure are in electrical contact and the conductor elements of the carrier plate can be contacted from the lower main surface of the carrier plate with a power source; and - the step of contacting the conductor elements of the carrier plate from the lower major surface of the carrier plate with a power source.

12. The method of claim 11 wherein the composite body is as defined in any one of claims 1 to 9.