Spacer fabric, spacer fabric section and heatable cladding element

Abstract

A spacer fabric with a first flat knitted fabric layer (1) comprising conductive threads (4), a second flat knitted fabric layer (2) and spacer threads (3) connecting the knitted fabric layers (1, 2), wherein the conductive threads (4) have an electrically conductive coating (7) and wherein in the first knitted fabric layer (1) adjacent conductive threads (4) are connected to one another in direct electrical contact over the entire surface or in conductive strips (5) running along a production direction (P), characterized in that the conductive threads (4) are formed from a plastic multifilament yarn (6) provided with the coating, have a fineness of less than 250 dtex and are knitted in the first knitted fabric layer (1) with a lay over at least two wales, wherein in the conductive threads (4) the proportion of the conductive coating (7) is less than 50 wt.-% and wherein the individual filaments of the plastic multifilament yarn (6) are each surrounded by the coating (7) and are movable relative to one another.

Description

[0001] The present invention relates to a spacer knitted fabric with a first flat knitted fabric layer comprising conductive threads, a second flat knitted fabric layer and spacer threads connecting the knitted fabric layers, wherein the conductive threads have an electrically conductive coating and wherein in the first knitted fabric layer adjacent conductive threads are connected to one another in direct electrical contact over the entire surface or in conductive strips running along a production direction.

[0002] Various approaches are known for providing a spacer fabric with electrical conductors, particularly for heating purposes.

[0003] According to DE 199 03 070 A1, DE 10 2009 013 250 B3, and DE 42 39 068 A1, individual heating wires that are not connected to each other and run in the direction of production are contacted with a transverse connecting conductor. The contacting is relatively complex, and the possible applications of the described spacer fabric equipped with heating wires are also limited. If a heating wire is interrupted, heating cannot occur across the entire area of ​​the corresponding width.

[0004] DE 103 42 285 A1 discloses various options for integrating heating conductors into a spacer fabric. According to a first solution, conductive textile yarns are inserted between the two flat knitted layers in the area of ​​the spacer threads. The corresponding heating conductors are thus protected to a certain extent, but the inherently advantageous insulating effect of the spacer fabric is somewhat lost due to the central arrangement of the heating conductors. Furthermore, inserting the heating conductors into the pole area, i.e., between the spacer threads, requires complex contacting.

[0005] Alternatively, DE 103 42 285 A1 proposes connecting conductive yarns to at least one of the knitted fabric surfaces by stitching. However, this method has the disadvantage that an additional, complex process step is required, and the yarns incorporated by stitching can lead to significant unevenness in the spacer fabric.

[0006] Finally, DE 103 42 285 A1 proposes, as a further alternative, a purely two-dimensional woven, knitted, or warp-knitted fabric made of conductive textile yarn and then laminated onto the spacer fabric. This requires the two materials to be manufactured in separate process steps, and a separate bond must also be made. Especially with the described textile materials, bonding is often difficult due to their open textile structure. The additional laminating adhesive can result in unpleasant odors during use and increased costs for disposal or recycling.

[0007] DE 202 20 752 U1 discloses a textile material laminated from at least two layers. In this two-dimensional material, one of the layers is made of conductive threads and another of non-conductive threads. This textile material, which lacks any cushioning effect, is also complex to produce.

[0008] Generic spacer fabrics with conductive threads arranged in a first layer are known from DE 10 2006 038 611 A1 and DE 10 2006 038 612 A1, wherein various variants of such a spacer fabric intended for heating purposes are generally described. One of the layers can consist entirely of conductive threads, in particular metal threads. Metallic strands are suggested for this purpose because solid wires are difficult to process on a knitting machine, and conventional wires can at best be inserted into the spacer fabric but cannot be meshed.

[0009] Despite the significant demand for easy-to-handle, heatable spacer fabrics, the spacer fabrics described in DE 10 2006 038 611 A1 and DE 10 2008 038 612 A1 have not been able to gain widespread acceptance in practice. This is primarily due to the fact that the corresponding materials could not be produced at a reasonable cost and in satisfactory quality.

[0010] DE 10 2009 003 867 A1 discloses a conductive polymer tape or polymer fabric that can be used as a heating element. Within the scope of various design options, it is proposed to provide non-conductive polymer fibers with a conductive coating.

[0011] Against this background, the present invention is based on the object of providing a spacer fabric with the features described above, which is easy to manufacture and has good functional properties. Furthermore, a spacer fabric section formed therefrom and a heatable covering element comprising such a spacer fabric section are to be provided.

[0012] The subject matter of the invention and the solution to the problem are a spacer fabric according to patent claim 1, a spacer fabric section according to patent claim 7 and a heatable cladding element according to patent claim 11.

[0013] Starting with the spacer fabric described above, the invention provides that the conductive threads are formed from a plastic multifilament yarn provided with the coating, have a fineness of less than 250 dtex, and are knitted in the first knitted layer with a drape over at least two wales and preferably also form loops, wherein the proportion of the conductive coating in the conductive threads is less than 50 wt.%, preferably 15 wt.%, particularly preferably less than 5 wt.%. The individual filaments of the multifilament core are not electrically conductive and thus form a non-conductive core. The individual filaments are each surrounded by the coating and remain movable relative to one another. The conductive threads then externally resemble a metal strand - at least with a metallic coating - but have fundamentally different properties due to the core-sheath structure.

[0014] Within the scope of the invention, it is particularly important that the conductive threads run over at least two wales during laying, thus conductively connecting adjacent wales, whereby a conductive surface is then created in the corresponding knitted layer of the entire spacer fabric. Preferably, the conductive threads also form loops, although this is not absolutely necessary within the scope of the invention. For example, it can also be provided that the conductive threads are knitted over at least two wales as a partial weft and thus run in a zigzag pattern without forming loops themselves. As a further thread system, threads can then be provided in the first knitted layer, for example, which run only along one wale in a fringe pattern. The threads of this further thread system can be either non-conductive or conductive.

[0015] Even if a relatively large proportion of up to 50 wt.% is planned for a metallic coating, the layer thicknesses on the individual filaments remain relatively low due to the higher density of the coating. The core, in the form of the individual filaments, maintains a very high degree of mobility and deformability of the electrically conductive threads.

[0016] While according to the prior art, metal strands or monofilament yarns provided with a metallic coating are comparatively stiff and therefore difficult to process, according to the invention, a relatively thin material with less than 250 dtex is provided for the conductive threads, wherein in addition the electrically conductive coating leading to stiffening is relatively thin and amounts to less than 50 wt.% based on the core of the plastic filaments.

[0017] The plastic multifilament yarn is characterized by greater flexibility than a monofilament yarn produced using the same material. Surprisingly, stitches can be easily formed within the scope of the invention, whereby the conductive coating remains intact despite the high flexibility of the plastic multifilament yarn as the core and the strong bending of the conductive threads during the production of individual stitches. The conductive coating is usually present on the individual filaments as a circumferentially closed sheath, so that this closed sheath shape can also ensure sufficient resistance of the coating despite severe bending. The conductive coating can deform to a certain extent without, however, flaking onto or off the plastic multifilament yarn.

[0018] The electrically conductive coating can be designed in different ways within the scope of the invention.

[0019] According to a first variant, a metallic coating is used, with particular consideration being given to metals or metal alloys with good corrosion resistance and a certain degree of deformability. In addition, the costs for the conductive threads with the metallic coating must also be taken into account. For example, the conductive threads can have a metallic coating based on silver, which is easily deformable and has relatively good resistance. Especially with a comparatively low weight proportion of the metallic coating, economical use is still possible in many applications despite the comparatively high costs of the coating. A disadvantage, however, is that silver also forms a thin oxide layer on the surface, which, depending on the application, can lead to uneven contact or uneven current flow to a certain extent.

[0020] Copper, for example, could also be considered as a more cost-effective alternative to silver, although even then, surface oxidation with the disadvantages described above cannot be completely ruled out. Gold can also be used as a metallic coating to avoid the disadvantages described above, although this would incur significantly higher costs.

[0021] According to an alternative embodiment of the invention, a non-metallic coating is provided. Graphite or another carbon-based material is particularly suitable, as this generally prevents the formation of an undesirable oxide layer. Graphite is also characterized by relatively good mobility. However, other non-metallic coatings are also generally possible, and these can also be formed on a polymer basis, in the manner of a conductive lacquer or the like.

[0022] Finally, a multilayer coating is also fundamentally possible. For example, various metallic or non-metallic layers can be combined to achieve an optimized match for the specific application in terms of conductivity on the one hand and electrical contact on the surface on the other. For example, a multilayer coating with an inner layer of copper or silver, onto which a thin top layer of gold is vapor-deposited, is conceivable.

[0023] The design of the conductive threads made from the coated plastic multifilament yarn is relevant not only directly during the knitting process, but also during subsequent finishing. During finishing, the textile material is subjected to a temperature that, while not melting the individual threads and filaments, allows tensions in the threads caused by their bends in the stitches of the spacer fabric to be reduced through the viscous flow of the polymer chains. While plastic threads initially strive to return to their straight original shape due to internal tensions, these tensions are eliminated during finishing, with the bent state in the knitted fabric then, in a sense, being "frozen" in place by the cooling process after finishing.According to the invention, the individual filaments of the plastic multifilament yarn, preferably coated individually, are also movable relative to each other to a certain extent, which results in improved processability during production and finishing. Especially with a metallic coating, advantages can arise during finishing because the heat is effectively conducted through the coating to the filaments.

[0024] Although the first flat knitted layer contains conductive threads, the spacer fabric remains relatively soft and has a pleasant feel. According to the invention, known knitting patterns of non-conductive spacer fabrics can be largely used, with the first flat knitted layer then being formed partially or completely with conductive threads.

[0025] As previously explained, silver is preferred for a metallic coating, although this results in relatively high material costs. Silver is characterized by good conductivity, low corrosion susceptibility, and good formability. Due to these properties, the metallic coating can be made very thin depending on the application, with the metallic coating then having only a minor impact on the mechanical properties of the conductive threads. Stiffening due to the metallic coating can be kept to a minimum overall.

[0026] Within the scope of the invention, the weight proportion of the electrically conductive, in particular metallic, coating compared to the total weight of the conductive threads is preferably less than 15 wt.%, for example between 1 wt.% and 5 wt.%.

[0027] According to the invention, the conductive threads have a fineness of less than 250 dtex, with the fineness preferably being between 90 and 200 dtex. For example, conductive threads with a fineness of 110 dtex or 145 dtex can be used.

[0028] The number of individual filaments is preferably between 3 and 40 to ensure sufficient flexibility, low manufacturing costs, and good mechanical properties. The number of filaments is preferably between 12 and 30, for example, 24.

[0029] The second knitted fabric layer is preferably made of multifilament yarn with a fineness between 50 dtex and 340 dtex. Both the second knitted fabric layer and the filaments of the conductive threads made of plastic multifilament yarn can be made of polyamide, including polyamide copolymers such as PA6, polyester, especially PET, and polypropylene.

[0030] For the further design of the first knitted fabric layer, various design possibilities arise within the scope of the invention, although typically each conductive thread is connected to at least one other conductive thread in direct electrical contact. The electrical contact is achieved through the knitting pattern. In the simplest case, for example, adjacent conductive threads can be connected to one another by a tricot layup, although any other layup types are also possible, in which the conductive threads are guided over at least two wales and thus cross each other in certain areas.

[0031] Within the scope of the invention, the conductive threads can be arranged over the entire surface of the first knitted fabric layer. If the conductive threads are then provided as a single thread system, the first knitted fabric layer is formed exclusively from the conductive threads. However, it is also possible for the first knitted fabric layer to be formed from the conductive threads as the first thread system and a second thread system of non-conductive threads, for which purpose two or more guide rails are used to form the first flat knitted fabric layer.

[0032] Furthermore, it is possible for the first knitted layer to have conductive strips running along the production direction, in which case the conductive threads are only present in these conductive strips. Within the scope of such a configuration, groups of conductive threads can alternate with groups of non-conductive threads transverse to the production direction, with preferably at least ten conductive threads being provided to form each strip running in the production direction. However, with such a material, care must be taken to ensure that all conductive strips are suitably contacted, because no continuously conductive surface is formed.

[0033] Since the conductive threads in the first knitted layer are not only inserted but also meshed, they are also intimately connected to each other, so that good direct electrical contact is guaranteed simply by the conductive threads touching each other.

[0034] Within the scope of the invention, the spacer threads are typically formed from monofilament yarn to ensure the necessary compression strength and elasticity of the spacer fabric. The filament diameter can be, for example, between 30 µm and 100 µm, in particular between 55 µm and 80 µm. Since the monofilaments are incorporated into the two knitted fabric layers during production of the spacer fabric, the spacer threads also stiffen the two knitted fabric layers to a certain extent. Against this background, it is advantageous that, according to the invention, the use of conductive threads with a low fineness and a core made of plastic multifilament yarn with a relatively thin coating does not result in any further significant stiffening of the first flat knitted fabric layer.

[0035] The invention also relates to a spacer fabric section formed from the previously described spacer fabric, which in the simplest case is punched or cut out of a material web of the spacer fabric.

[0036] According to a preferred embodiment, the spacer fabric section has at least one opening at which both fabric layers with the spacer threads arranged between them are separated, whereby the conductive threads in the first fabric layer are also interrupted accordingly. Corresponding openings can be formed, for example, by punching or cutting.

[0037] Depending on the intended use of the spacer fabric section, the openings may initially be necessary solely due to design requirements. If the spacer fabric is used, for example, as part of a trim element for a motor vehicle, openings may be necessary on the door side, a roof liner, or the like to allow operating elements of the motor vehicle to be passed through the spacer fabric section. When the spacer fabric section is used on the side of a door, for example, it is often necessary to provide a recess for a handle or a lock operating element. The same applies, for example, when arranged in a roof liner if the interior trim is to be interrupted for lighting, a display element, or the like.

[0038] The invention offers the advantage that the flat arrangement of the conductive threads in strips or throughout the entire first knitted fabric layer, and the direct electrical contact between adjacent conductive threads, provide large-area conductive areas. If such a spacer fabric section is then provided with openings, a current can flow around the openings when current is applied, thus resulting in particularly flexible application possibilities.

[0039] A further advantage is that, within the scope of the invention, complex contacting can be dispensed with in some applications. Contacting can be achieved, for example, by simple terminals, conductive adhesive or the like, whereby only a point connection can be provided, from which an even current distribution is then possible due to the surface-conductive properties. Alternatively, a linear connection can also be used to ensure particularly reliable and even contacting. In the case of a metallic coating, contacting can also be achieved by soldering or welding. If necessary, the heat input required for this can also be achieved directly by applying current to the arrangement. For example, a low-melting contact conductor ora contact conductor provided with a low-melting sheath is placed on top, whereby fusion then occurs directly by applying a current that is higher (compared to later operation).

[0040] Preferably, spaced-apart electrical contacts are provided, which are connected directly to the conductor threads running along the contact surface via point-like or linear contact surfaces. The point-like or linear contact surfaces each preferably extend over less than 5%, in particular less than 2%, of the total area of ​​the entire spacer fabric section.

[0041] If the spacer fabric section is provided with openings and spaced-apart electrical contacts, it is also possible to provide a plurality of openings arranged in such a way that, when current is applied to the electrical contacts, a more even current distribution results across the surface than with a spacer fabric section without openings but otherwise of the same design. However, it should be noted that the current must be guided around the openings, which can result in a higher current density and greater heating locally. If the openings are too large and the webs left at the sides of the openings are therefore too small, there is a risk of overheating or burnout.However, if the essential aspects for current conduction are taken into account during design, openings, incisions, or similar can be used, depending on the application, to optimize current flow and thus heat generation. This aspect will be discussed further below.

[0042] While in a full-surface, uninterrupted spacer fabric section the greatest current flow results from a direct connection between the two contacts, the current flow can be further manipulated and optimized through openings.

[0043] Instead of openings, it may also be sufficient to create only individual separation areas in the first knitted layer, which contains the conductive threads. In this case, non-conductive barriers are created by separating cuts or similar methods to positively influence the overall current flow. If only the first knitted layer is cut in certain areas, the mechanical properties of the spacer fabric remain largely unchanged.

[0044] The measures described make it possible to locally modify and adjust the temperature development in the spacer fabric section according to the respective requirements. For this purpose, it is also conceivable to subsequently provide areas of the first flat knitted fabric layer with an additional conductive coating to reduce the resistance there and thus also the local heat development when the spacer fabric is used for heating purposes.

[0045] The invention further relates to a heatable cladding element with the previously described spacer fabric section and with a cover layer arranged on the spacer fabric section. The cover layer is preferably arranged on the first fabric layer provided with the conductive threads, so that a beneficial insulating effect is ensured underneath by the spacer threads and the second fabric layer. The properties of the spacer fabric then ensure that the side of the heatable cladding element provided with the cover layer is efficiently heated, while undesirable heat losses are generally avoided on the opposite side.

[0046] The heated trim element can be used, for example, in the automotive sector to cover the door side, a center console, an armrest, the footwell, the headliner, the dashboard, or the steering wheel. The heated trim element can also be part of a seat heater in a motor vehicle. The spacer fabric section can be provided with a covering layer made of leather, synthetic leather, foil, another textile, or the like.

[0047] The heatable cladding element can also be used in the technical field of construction and architecture to create heatable soundproofing panels, room dividers, wall coverings, ceilings or underfloor heating.

[0048] In the medical field, a spacer fabric section according to the invention can be used with or without an additional cover layer for couches, heated blankets, armchairs, or chairs. It is also possible to create heatable bandages.

[0049] Other applications are also conceivable, such as use in heated clothing, heated insoles or heated gloves, which are particularly suitable for low-temperature applications.

[0050] Other possible uses include warming pads in strollers, warming mattress pads, outdoor use as anti-icing protection or as vegetation support or protection.

[0051] When silver is used as a conductive coating, the antibacterial effect of silver can also be used as an additional advantage in some of the applications mentioned.

[0052] In a majority of the described applications, various advantageous aspects of the spacer fabric according to the invention or the spacer fabric section according to the invention are used, which is characterized by high elasticity and adaptability, good heating properties, application-oriented variable shape (through the formation of openings and individual cutting), optimal drapability and easy production compared to known designs.

[0053] The invention is explained below with reference to a drawing that represents only one exemplary embodiment. It shows: Fig. 1 the structure of the spacer fabric, Fig. 2 an alternative design of the spacer fabric according to Fig. 1, Fig. 3 a section through a conductive thread of a first knitted layer of the spacer fabric according to Fig. 1 or Fig. 2, Fig. 4 a strip-shaped spacer fabric section with an opening, Fig. 5 a spacer fabric section with several openings and spaced-apart electrical contacts, Fig. 6 an alternative design of the spacer fabric section according to the Fig. 5.

[0054] The Fig. 1 shows the basic structure of a spacer fabric according to the invention with a first flat knitted fabric layer 1, a second flat knitted fabric layer 2 and spacer threads 3 connecting the knitted fabric layers 1, 2. The first knitted fabric layer 1 has conductive threads 4, which are described below in connection with the Fig. 3 are further described.

[0055] According to the Fig. 1, the entire first knitted fabric layer 1 is formed from conductive threads 4, whereby according to the detail section of the Fig. 1, the electrically conductive threads 4 are arranged in a tricot lay, so that the conductive threads 4 form loops in the first knitted fabric layer 1 over two wales. By forming loops, adjacent conductive threads 4 are tightly intertwined and electrically connected to one another by direct electrical contact on the surface of the conductive threads 4.

[0056] The spacer fabrics according to Fig. 1 and Fig. 2 differ in that according to the Fig. 2 the conductive threads 4 are arranged only in conductive strips 5, wherein at least ten threads running in a production direction P are preferably provided to form the conductive strips 5. In the transverse direction Q, groups of conductive threads 4 thus alternate with groups of non-conductive threads.

[0057] The Fig. 3 shows a detailed cross-section of the conductive threads 4 provided within the scope of the invention. According to the invention, the conductive threads 4 comprise a plastic multifilament yarn 6 provided with a coating 7, wherein the plastic multifilament yarn typically comprises between 3 and 40, for example 24, filaments. The proportion of the conductive coating 7, based on the total weight of the conductive threads, is less than 50 wt.%, in particular less than 15 wt.%, for example between 1 wt.% and 5 wt.%. The conductive coating 7 can be either metallic or non-metallic. Reference is made below merely by way of example to a metallic coating 7 in the form of silver as a preferred embodiment.

[0058] The core-shell structure of the plastic multifilament yarn 6 provided with the coating 7 allows the conductive threads 4 to be particularly flexible, while the metallic silver coating 7 is characterized by low electrical resistance, allowing the metallic coating 7 to be made particularly thin. Surprisingly, the metallic coating 7 is not destroyed when the filaments are formed into loops, which is precisely where the relatively soft properties of silver come in. The thin metallic coating 7 also ensures that the filaments of the plastic multifilament yarn 6 are only slightly stiffened.

[0059] The Fig. 4 shows a spacer fabric section provided with an opening 8 for testing purposes. The spacer fabric section can be made of a spacer fabric according to the Fig. 1, although a similar behavior results when a spacer fabric according to the Fig. 2 a conductive strip 5 is provided with an opening 8.

[0060] In the Fig. 4, the spacer fabric section is provided at its ends with electrical contacts 9 in the form of simple connection terminals. Since the spacer fabric is conductive across its entire surface at the first layer 1, contact via connecting conductors or the like can be omitted depending on the application. However, linear contact can be advantageous for uniform, reliable current distribution.

[0061] In the Fig. To illustrate the heating process, lines corresponding to a specific temperature are drawn in Figure 4. The temperature curve is thus represented in the manner of a contour map or topographical map.

[0062] First, it can be seen that the temperature decreases toward the edges of the spacer fabric section due to increased cooling through heat dissipation to the environment and the reduced current flow. Beyond that, however, a largely uniform temperature profile is observed across a large portion of the spacer fabric section.

[0063] At the opening 8, the conductive threads 4 are interrupted by the opening 8, so that the current flow must occur around the opening 8, resulting in a larger current there and thus an increased heating output. According to the invention, however, due to the planar conductive properties of the spacer fabric, openings 8 can be introduced into the material, as long as the openings 8 are not too large and the webs remaining on the sides of the openings 8 have sufficient conductivity. The openings 8 can, for example, be provided for purely practical reasons, for example to provide feedthroughs or to be able to pass mechanical connection elements through. Corresponding openings 8 can, for example, be necessary or expedient in order to use the spacer fabric section as a heatable cladding element with a cover layer.

[0064] The Fig. Figure 5 shows that virtually any desired openings 8 can be provided in a spacer fabric section, with such a spacer fabric section expediently being provided with electrical contacts 9 at opposite ends. In addition to connecting terminals, electrical contacts can also be easily glued onto the first fabric layer 1 in order to selectively contact the conductive threads 4 running there.

[0065] In the Fig.6 also indicates that the position of the openings 8 can also influence the current distribution and thus the heating of the spacer fabric section and adapt it to the respective requirements. For this purpose, instead of continuous openings 8, only incisions can be provided in the first fabric layer 1, which sever the conductive threads 4 in certain areas. Depending on the requirements, the measures described can achieve very uniform heating, or individual areas can be heated to a greater or lesser extent, or not at all.

[0066] If the conductive threads 4 are not interrupted, the heat conduction within the material also contributes to a uniform heat distribution, with silver as the preferred metallic coating 7 having particularly good thermal conductivity.

Claims

[1] A spacer fabric comprising a first flat knitted fabric layer (1) comprising conductive threads (4), a second flat knitted fabric layer (2) and spacer threads (3) connecting the knitted fabric layers (1, 2), wherein the conductive threads (4) have an electrically conductive coating (7) and wherein in the first knitted fabric layer (1) adjacent conductive threads (4) are connected to one another in direct electrical contact over the entire surface or in conductive strips (5) extending along a production direction (P), characterized bythat the conductive threads (4) are formed from a plastic multifilament yarn (6) provided with the coating, have a fineness of less than 250 dtex and are knitted in the first knitted fabric layer (1) with a lay over at least two wales, wherein in the conductive threads (4) the proportion of the conductive coating (7) is less than 50 wt.% and wherein the individual filaments of the plastic multifilament yarn (6) are each surrounded by the coating (7) and are movable relative to one another. [2] Spacer fabric according to claim 1, characterized by that the conductive coating (7) consists of metal, in particular silver. [3] Spacer fabric according to claim 1 or 2, characterized by that the filaments of the plastic multifilament yarn (6) consist of a material selected from the group polyamide, polyester and polypropylene. [4] Spacer fabric according to one of claims 1 to 3, characterized bythat at least ten conductive threads (4) are provided for forming strips (5) running in the production direction (P). [5] Spacer fabric according to one of claims 1 to 3, characterized by that the conductive threads (4) are arranged over the entire surface in the first knitted fabric layer (1), wherein the first knitted fabric layer (1) is formed exclusively by the conductive threads (4). [6] Spacer fabric according to one of claims 1 to 5, characterized by that the spacer threads (3) are formed from a monofilament yarn with a filament diameter between 55 µm and 80 µm. [7] A spacer fabric section formed from a spacer fabric according to any one of claims 1 to 6. [8] Spacer fabric section according to claim 7, characterized bythat at at least one opening (8) both knitted layers (1, 2) with the spacer threads (3) arranged therebetween are separated and the conductive threads (4) in the first knitted layer (1) are interrupted there accordingly. [9] Spacer fabric section according to claim 6 or 7, characterized by spaced-apart electrical contacts (9) which are connected via point contact surfaces directly to the conductive threads (4) of the first knitted layer (1) running along the contact surface. [10] Spacer fabric section according to claims 8 and 9, characterized by that a plurality of openings (8) are provided which are arranged in such a way that when current is applied to the electrical contacts (9), a more uniform surface current distribution results than in the case of a spacer fabric section which is not provided with openings (8) but is otherwise of the same design. [11] Heatable cladding element with a spacer fabric section according to one of claims 7 to 10 and with a cover layer arranged on the spacer fabric section.

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