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EP-4736584-A1 - EXTENSIBLE CONDUCTIVE STRUCTURE

EP4736584A1EP 4736584 A1EP4736584 A1EP 4736584A1EP-4736584-A1

Abstract

The invention relates to a conductive structure (1) for transmitting electrical signals or electrical power, comprising a substrate layer (10) made of a polymer material and a two-phase or multi-phase conducting track (11), which is disposed on the substrate layer (10) and contains a first electrically conductive layer (20) and a second electrically conductive layer (30) having an elongation at break that is greater than an elongation at break of the first layer (20).

Inventors

  • Kneer, Janosch
  • Kegel, Isabell
  • Schleuniger, Juerg

Assignees

  • ContiTech Deutschland GmbH

Dates

Publication Date
20260506
Application Date
20240610

Claims (14)

  1. 1. Conductive structure (1) for transmitting electrical signals or electrical power with a substrate layer (10) made of a polymeric material and a two- or multi-phase conductor track (11) arranged on the substrate layer (10), comprising: - a first electrically conductive layer (20) and - a second electrically conductive layer (30) having an elongation at break which is greater than an elongation at break of the first layer (20).
  2. 2. Conductive structure (1) according to claim 1, wherein the second layer (30) has a uniform elongation which is greater than the elongation at break of the first layer (20).
  3. 3. Conductive structure (1) according to claim 1 or 2, wherein the breaking strain of the first layer (20) is within an elastic strain range of the second layer (30).
  4. 4. Conductive structure (1) according to one of the preceding claims, wherein the first layer (20) contains, in particular consists of, an electrically conductive material, in particular a metal.
  5. 5. Conductive structure (1) according to claim 3, wherein the electrically conductive material is a solid material or a printed and/or sintered material.
  6. 6. Conductive structure (1) according to one of the preceding claims, wherein the second layer (30) contains, in particular consists of, a dielectric, in particular polymeric material with conductive particles and/or clusters of such particles embedded therein.
  7. 7. Conductive structure (1) according to one of the preceding claims, wherein the first layer (20) has an electrical conductivity that is greater than an electrical conductivity of the second layer (30).
  8. 8. Conductive structure (1) according to one of the preceding claims, wherein the conductive structure (1) is constructed in the following order: - substrate layer (11), first layer (20), second layer (30); or - substrate layer (11), second layer (30), first layer (20).
  9. 9. Conductive structure (1) according to one of the preceding claims, wherein the conductive structure is a sensor (or a part thereof) and/or an antenna (or a part thereof).
  10. 10. Product containing a polymeric material with elastic properties, in particular polymeric sheet material, in particular artificial leather, or belt (2), in particular drive belt or conveyor belt, containing a polymeric material (3), in particular with tension members embedded therein and extending in the longitudinal direction (L) of the belt (2), characterized by a conductive structure (1) according to one of the preceding claims.
  11. 11. Product according to claim 10, wherein the conductive structure (1) is embedded in the polymeric material of the product or attached to the product, in particular glued and/or laminated.
  12. 12. Use of a conductive structure (1) according to one of claims 1 to 8 for forming an electronic component, in particular a sensor or an antenna.
  13. 13. Use of a conductive structure (1) according to one of claims 1 to 8 for the electrical connection of two electronic components or voltage or power supply of an electrical component.
  14. 14. Use according to claim 12 or 13, wherein the conductive structure (1) is arranged, in particular fastened, on a flat or curved surface.

Description

Description Stretchable conductive structure The present invention relates to an electrically conductive structure for transmitting electrical signals or electrical power with the features of claim 1. In particular, the present invention relates to conductive structures which are integrated for signal transmission in products containing a polymeric material with elastic properties, such as drive belts or conveyor belts, and are exposed to corresponding bending and tensile loads. In many applications, particularly dynamic ones in the area of goods transport or power transmission, the belts used are subjected to bending and stretching loads. If an electrical or electronic function or sub-function is integrated into such systems, the corresponding conductive structures - such as power or signal cables, antennas, sensors, etc. - must also withstand this mechanical load, ideally with little or no impairment of the transmission capacity of electrical signals or electrical power. There is also a need for stretchable and/or bendable electrically conductive structures for use in materials that are subjected to stretching and/or bending loads - for example during their processing - for example when a component is covered with such a material or the material is laminated. The object of the present invention is to provide a conductive structure with improved signal transmission properties under bending and/or tensile loads. This object is achieved by a conductive structure having the features of claim 1. Preferred features are the subject of the dependent claims. Further advantages and features are contained in the general description and the embodiments. The present invention also relates to a product containing a polymeric material with elastic properties which contains such a conductive structure, according to claim 10. Furthermore, the use of such a conductive structure according to claims 12 or 13 is also the subject of the invention. The conductive structure according to the invention for transmitting electrical signals or electrical power contains a substrate layer made of a polymeric material, in particular a flexible and stretchable material, and a two-phase or multi-phase conductor track arranged on the substrate layer. The conductor track contains a first electrically conductive layer and a second electrically conductive layer with an elongation at break that is greater than an elongation at break of the first layer. The invention is based on the idea of combining two electrically conductive layers with different expansion properties. Both layers contact each other and, as a layered composite, form the conductor path of the conductive structure. In this way, in situations in which such a high expansion and/or bending load acts on the conductive structure that the conductivity of the first layer is impaired, a continuous current path can be maintained by means of the second layer, i.e. continuous conductivity can be ensured. Impairments to the conductivity of the first layer under high expansion and/or bending loads can be caused, for example, by plastic deformations or even micro-fractures in the first layer. As a rule, the fracture edges of the first layer come back together when the conductive structure is unstretched or less stretched, so that in situations of smaller expansion and/or bending loads, both the first and the second layer contribute to optimal conductivity of the structure. The determination of the elongation at break depends on the material used. For metallic materials, the elongation at break is the permanent change in length of a sample in the tensile test after the break has occurred, based on the initial measuring length. For polymer materials, the elongation at break is the last recorded elongation value in the tensile test before the Stress has dropped to less than or equal to 10% of the strength. In some embodiments of the invention in which a metallic material is used for the first layer and a polymeric material (optionally with metal particles embedded therein) is used for the second layer, it may be necessary to determine the elongation at break of the first layer using the measurement method for metallic materials and to determine the elongation at break of the second layer using the measurement method for polymeric materials. Preferably, the elongation at break of the substrate layer is greater than or equal to the elongation at break of the second conductive layer. In a preferred embodiment of the conductive structure according to the invention, the second layer has a uniform elongation that is greater than the breaking elongation of the first layer. In this way, a conductive structure is provided that can withstand even greater stretching and/or bending loads. The uniform elongation is the elongation in the tensile test up to which the sample stretches evenly over its length and no constriction occurs. In a further preferred embodiment of the conductive structure according to