Arrangement for a textile electronic circuit

Abstract

Arrangement for a textile electronic circuit, characterized by a textile substrate (1) with a conductive structure (2) applied as an electrically conductive layer to the textile substrate, with at least one antenna arrangement and at least one electronic component (3) contacted with the conductive structure and attached to the textile substrate.

Description

[0001] The invention relates to an arrangement for a textile electronic circuit according to the preamble of claim 1.

[0002] Textile electronic circuits are well-known. They are used particularly where electronic functions are required in connection with the handling, processing, and use of textile materials and objects made from them, especially clothing. Examples include RFID antennas embedded in textiles or the positioning of specific sensors within them.

[0003] According to the state of the art, in known textile electronic circuits, an electronic component, such as a semiconductor chip, is positioned on a textile substrate. The textile substrate contains a conductive thread woven into the fabric with a specific orientation. The electronic component is contacted by the woven thread, so that the textile substrate, acting as a carrier for the electronic component, now realizes the electronic circuit. The conductive thread can, for example, function as an RFID antenna, so that the entire assembly of textile substrate, electronic component, and RFID antenna forms a textile RFID tag.

[0004] DE 10 2007 008 316 A1 discloses, by way of example, a textile material with a circuit module and an antenna. According to the publication, the antenna is designed as an electric field radiator for an operating frequency in the UHF or microwave range. It consists of components of the textile material itself in the form of conductive thread structures. These are incorporated into the textile structure within a standard textile manufacturing process, namely by weaving.

[0005] German patent DE 10 2011 106 648 A1 discloses a portable data storage device with an antenna. According to the teaching disclosed therein, the antenna is produced by connecting longitudinal and transverse threads of an electrically conductive fabric.

[0006] However, such textile electronic circuits have several disadvantages. A woven-in electrically conductive thread modifies an existing textile structure and cannot be arbitrarily combined with every given basic textile structure. The resulting textile substrates cannot then be used for garments, functional textiles, etc., as is the case with known, unmodified textiles. Furthermore, the electrically conductive threads have different mechanical properties than the other threads of the textile, which can sometimes lead to breakage of the woven-in conductor structures. Finally, conductive threads must be kept on hand during the manufacturing process, especially during weaving or knitting, which generally complicates the textile production. In addition, existing textiles cannot be retrofitted functionally in this way, or only with great difficulty.

[0007] The underlying problem of the invention is therefore to eliminate the aforementioned disadvantages.

[0008] The problem is solved by an arrangement for a textile electronic circuit with the features of claim 1. The arrangement for a textile electronic circuit is characterized by a textile substrate with a conductive structure applied as an electrically conductive layer to the textile substrate, comprising at least one antenna arrangement and at least one electronic component contacted with the conductive structure and attached to the textile substrate.

[0009] According to the invention, the conductive structure is therefore not part of the textile structure of the textile substrate itself, but is applied to the textile substrate as an additional coating, wherein at least one electronic component is in contact with this conductive structure and is thereby attached to the textile substrate. This configuration makes it particularly possible to retrofit existing textiles accordingly by means of the coating and to easily transform them into a carrier for a corresponding electronic circuit.

[0010] The conductive structure includes at least one antenna array. This transforms the textile substrate, together with the electronic component mounted on it, into a means for wireless data transmission.

[0011] Advantageously, the textile substrate consists of a tightly woven, low-stretch textile, in particular a woven, knitted, and / or crocheted fabric. This avoids strain fractures or non-conductive gaps in the conductive structure while maintaining the flexibility of the entire assembly.

[0012] The low-stretch fabric is in particular a synthetic fiber or natural fiber fabric or a polyester taffeta.

[0013] In one embodiment, the conductive structure consists of a solidified paste or powder comprising a binder and a proportion of electrically conductive particles.

[0014] In one embodiment, the conductive structure is applied to the textile substrate as a printed structure, in particular a screen-printed structure, or as a thermal transfer printing structure.

[0015] Another possible variant involves using a stenciled powder coating structure as the conductive layer. In this case, the textile substrate is coated with a powder applied through a stencil, thereby creating the conductive structure.

[0016] In another embodiment, the conductive structure is a sintered structure, in particular a laser sintered structure. Here, the conductive structure has been sintered into corresponding conductor tracks by means of a laser beam.

[0017] Virtually any electronic component can be combined with the conductive structure. In various embodiments, at least one electronic component is an RFID chip, a BLE chip (i.e., a so-called Bluetooth Low Energy chip for Bluetooth functionality), one or more sensors, and / or a battery. A display component, such as an LED or a screen, is also possible.

[0018] Depending on the embodiment, at least one electronic component is connected and contacted with the conductive structure via a soldered connection, an electrically conductive adhesive connection, an induction soldered connection, an induction adhesive connection and / or an ultrasonic welding connection.

[0019] In one embodiment, the arrangement of the textile electronic circuit is designed as a textile data carrier, in particular a textile radio data carrier.

[0020] As a further design, the textile electronic circuit can be covered with an adhered textile top layer.

[0021] Additionally, at least one electronic component and / or its contact can be covered with a flexible covering, in particular a silicone dome. This increases the mechanical resistance of the entire assembly.

[0022] Finally, in one variant, the textile substrate and / or the textile top layer can have an external hydrophobic coating. This provides water and weather protection.

[0023] In one embodiment, at least one of the electronic components arranged in the circuit has a radio interface. This eliminates the need for a separate radio chip as a separate electronic component. This interface can, of course, be integrated into an MCU or another component.

[0024] The aforementioned arrangement is specifically designed for use as a wireless textile sensor device. It can also be used as a wireless textile storage device and / or as a wireless textile transponder.

[0025] The aforementioned arrangement is also intended for use as a wireless textile display device.

[0026] The invention will be explained in more detail below using exemplary embodiments. The attached figures serve to illustrate this. Fig. 1 to 5. The same reference symbols are used for identical or equivalent parts.

[0027] It shows: Fig. 1 an exemplary basic structure, Fig. 1a an exemplary extended basic structure, Fig. 2 an exemplary structure of a textile dual-frequency RFID label, Fig. 3 an exemplary setup of a textile UHF-RFID data logger, Fig. 4 a representation of the data logger from Fig. 3 in cross-section, Fig. 4a A representation of an exemplary embodiment with a display component with an integrated radio interface, Fig. 4b a representation of an exemplary application with a sensor component with an integrated radio interface, Fig. 5 An exemplary cross-sectional representation of an RFID label with a textile top layer and a hydrophobic coating, Fig. 6 An exemplary representation of another embodiment of an RFID chip with a planar antenna arrangement.

[0028] Fig. Figure 1 shows an exemplary basic structure of the arrangement according to the invention. A textile substrate 1 with a conductive structure 2 is provided. Part of the conductive structure is designed as an antenna 4. An RFID chip 6 is also provided. Of course, an equivalent chip that can interact with the antenna assembly can be provided instead of the RFID chip 6.

[0029] Alternatively, any electronic component not involved in actual signal processing could be used in the circuit instead of the RFID chip. This electronic component could, for example, be a single battery that is inductively charged via antenna 4.

[0030] Fig. Figure 1a shows an exemplary extended basic structure of the arrangement according to the invention. The arrangement comprises the textile substrate 1 with the conductive structure 2 and several electronic components 3. The conductive structure forms, on the one hand, the section for the antenna 4 and, on the other hand, further conductor tracks 5. The electronic components 3 are specifically designed as the RFID chip 6, a sensor 6a, for example a magnetic field sensor or a temperature sensor, and a further integrated circuit 7, which can, for example, be a memory chip.

[0031] If only one electronic component is present, it can have an integrated radio interface. For example, appropriately integrated circuits can be used as the electronic component. Displays and / or sensors with a radio interface are possible examples, and these can be arranged as a single component on the substrate.

[0032] A fabric with a very tight weave and minimal stretch is best used as the textile substrate. The tight weave ensures a sufficiently continuous surface structure without interruptions or holes. Within the limits of the conductive coating's elasticity, the low stretch prevents the conductor tracks from stretching and potentially breaking. Otherwise, no further requirements are placed on the fabric itself. It goes without saying that the fabric must be electrically insulating.

[0033] Suitable fabrics for the textile substrate include PES or other synthetic fibers, as well as cotton fabrics or other natural fibers. PES stands for polyester. Taffeta, for example made of polyester and / or polyamide, can also be used. Such fabrics can also be used to cover the assembly. They can also be additionally coated with a hydrophobic material.

[0034] The conductive structures 2 consist, for example, of a paste or a powder. The paste and powder are subsequently solidified. Mixtures of a binder component and a component of conductive particles, such as silver or copper, are used. The paste or powder is applied to the textile substrate via screen printing, powder deposition, selective laser sintering, thermal transfer printing, or similar additive manufacturing processes and subsequently solidified.

[0035] The electrically conductive coating offers the advantage of more efficient and therefore more cost-effective manufacturing. Additionally, it simplifies the application of electronic components.

[0036] The homogeneity of the resulting coating is crucial, depending on the properties of the textile substrate. If the substrate is too inhomogeneous, particularly with low thread density, an uneven surface, or large mesh sizes, the electrical conductivity and / or surface resistance of the coating will be adversely affected. The edge sharpness of the fabricated structure is also significant. High edge sharpness ensures sufficiently good insulation between the conductor tracks at small spacings and thus defines the minimum achievable structure size. However, by adhering to the relevant boundary conditions, it is possible to minimize the size of the fabricable structures, enabling, in particular, the direct placement of a packageless IC onto a footprint with a gap in the mid to low three-digit micrometer range.

[0037] Furthermore, the homogeneity of the coating, due to its altered electrical parameters, has a significant influence on the properties of the manufactured radio antenna and thus on the performance and / or range of the radio data carrier. The antenna is optimized with respect to the required resonant frequency and input impedance, which depend primarily on the geometry used (dipole length, layer thickness, etc.) and are adapted to the chip used.

[0038] The conductive structures electrically connect the electronic components 3 to each other and simultaneously form the antenna arrangement 4. The antenna arrangement can be configured as an RFID-HF, RFID-UHF, RFID-NFC, RFID dual-frequency, BLE antenna, or other type of antenna.

[0039] The electronic components 3 are attached to the conductive structures 2, for example, by means of reflow soldering or an electrically conductive adhesive bond. In addition to or instead of the components already mentioned, battery elements can also be attached. Furthermore, a flexible covering of the entire or partial arrangement is also possible, as will be explained in more detail below.

[0040] Fig. Figure 2 shows an exemplary structure of a textile dual-frequency RFID label. The label again consists of the basic components: textile substrate 1, conductive structures 2, and electronic component 3. In this case, the conductive structures 2 consist of a dual-frequency RFID antenna array with an RFID UHF antenna 8 and an HF or NFC antenna array 9. These are configured differently according to the electromagnetic transmission frequencies used. The electronic component in this example is an RFID dual-chip 10, which is implemented as either an HF / UHF chip or an NFC / UHF chip.

[0041] The realization of the conductive structures, the design of the textile substrate, and the attachment of the chip comply with the requirements relating to Fig. 1 of the solutions mentioned.

[0042] Fig. Figure 3 shows an exemplary setup of a textile UHF RFID data logger. This also features the textile substrate 1, the conductive structures 2, and electronic components 3. The conductive structure here is a UHF RFID antenna 11, along with the corresponding conductor tracks. In this example, the electronic components 3 comprise a battery 12, a sensor 13, and a UHF RFID chip 14. Additionally, a hole 15 is provided for attaching the data logger to an object.

[0043] Fig. Figure 4 shows a representation of the data logger from Fig. 3 in cross-section. In this case, the battery 12 is applied as a screen-printed arrangement to the textile substrate, more precisely, to the conductive structure 2 located thereon, and thus to the antenna 11. The UHF RFID chip 14 is contacted with the conductive structure 2 by means of a conductive adhesive bond and is attached to the textile substrate. The sensor 13 is then soldered in place. A polyester taffeta fabric is used as the textile substrate 1.

[0044] Electronic components can also include control elements and / or displays. For example, external devices can be controlled directly or indirectly, while LEDs or displays in various designs can be attached to and connected to the textile substrate as display elements.

[0045] The Fig. 4a and Fig. Section 4b shows relevant examples. Fig. Figure 4a shows a textile substrate 1 with a conductive structure 2, which is implemented section by section as an antenna arrangement 4. The textile substrate contains in Fig. 4a a display 19, which in this example is implemented as a seven-segment display. The display internally contains a radio interface, for example an RFID interface or a Bluetooth interface. It can therefore communicate directly with external devices via the antenna arrangement 4 without any additional component.

[0046] Fig. Figure 4b shows a textile substrate 1 with a conductive structure 2, which is also implemented section by section as an antenna arrangement 4. The textile substrate contains in Fig. 4b a sensor 20 with an internal radio interface. This can also be an RFID or Bluetooth interface. The sensor 20 can thus communicate directly with external devices via the antenna arrangement 4 without any additional component. The sensor 20 can be a sensor for any measured quantity. In particular, a proximity sensor, which, for example, registers the presence of a person, or a position sensor, which detects the position of an object in space, are possible. Together with the textile substrate, the sensor can be connected to external textile surfaces, for example, by sewing or gluing.

[0047] The examples of implementation from the Fig. 4a and Fig. 4b technologies are particularly advantageous in automotive engineering, especially in vehicle interiors. For example, proximity sensors can be integrated into seat cushions or the vehicle's headliner, and they can also be attached to the dashboard using adhesive or other methods. These sensors can detect the number of people in the vehicle and the occupancy of the available seats, transmitting this information wirelessly to the vehicle's onboard computer, which then adjusts the headlight settings accordingly.

[0048] Fig. Figure 5 shows an exemplary representation of an RFID label with a textile cover layer and a hydrophobic coating. In this example, the textile substrate 1 consists of a PES fabric. This fabric is provided with the conductive structure 2 as previously described. In this example, an RFID chip, in particular an RFID dual-chip, is bonded to the conductive structure using ICP as the electronic component 3. The RFID chip is covered with a flexible housing 15a, for example, a silicone dome. The entire assembly consisting of the conductive structure 2 and the electronic component 3 with the flexible housing 15a is covered with an adhesive layer 16. This adhesive layer serves both as a potting compound for the electronic circuitry located on the textile substrate and simultaneously fixes a cover layer 17 that covers the entire electronic circuitry.In an advantageous design, the adhesive layer is implemented as an elastic layer. The top layer 17 can consist of the same textile material as the textile substrate, in this example a PES fabric.

[0049] In addition, this entire arrangement is provided on both sides with a hydrophobic coating 18.

[0050] Fig. Figure 6 shows an embodiment with a planar conductive structure 2 which can function as an antenna with an electronic component, in particular with an RFID chip 6. Fig. Figure 6 shows by way of example that the conductive structure can be applied not only as a narrow conductor track, but also over a sufficiently large area to the textile substrate 1 and can also act as an antenna.

[0051] Such arrangements can therefore be designed to be application-oriented, depending on the requirements. Their applications extend, for example, to the medical field, particularly in the areas of medical sensor technology and functional medical textiles. Use in the clothing sector is also possible, for instance, for the interaction of electronic circuitry on the textile carrier with a communication device worn within the garment. Finally, these arrangements are also suitable for functional textiles and functional clothing.

[0052] The arrangement according to the invention has been explained in more detail with reference to exemplary embodiments. Further embodiments are described in the dependent claims. Further configurations are possible within the scope of expert knowledge. Reference symbol list 1 textile substrate 2 conductive structure 3 electronic component 4 antennas 5 conductor track 6 RFID chips 6a Sensor 7 Integrated Circuit 8 RFID UHF antenna 9 RF or NFC antenna arrangement 10 RFID dual-chip 11 UHF RFID antenna 12 batteries 13 Sensor 14 UHF RFID chips 15 holes 15a flexible enclosure 16 adhesive layers 17 Textile top layer 18 Hydrophobic coating 19" display element with integrated radio interface 20 sensors with integrated radio interface

Claims

[1] Arrangement for a textile electronic circuit, characterized by a textile substrate (1) with a conductive structure (2) applied to the textile substrate as an electrically conductive layer, with at least one antenna arrangement and at least one electronic component (3) contacted with the conductive structure and fastened to the textile substrate. [2] Arrangement according to claim 1, characterized by that the textile substrate (1) consists of a close-meshed, preferably slightly stretchable textile, woven fabric, knitted fabric or knitted fabric. [3] Arrangement according to claim 2, characterized by that the low-stretch fabric is a synthetic or natural fiber fabric or a polyester taffeta. [4] Arrangement according to one of the preceding claims, characterized by that the conductive structure (2) consists of a solidified paste or a powder consisting of a binder and a portion of electrically conductive particles. [5] Arrangement according to one of the preceding claims, characterized by that the conductive structure (2) is applied to the textile substrate as a printed structure, in particular a screen-printed structure or as a thermal transfer printed structure. [6] Arrangement according to one of the preceding claims, characterized by that the conductive structure (2) is a stenciled powder coating structure. [7] Arrangement according to one of the preceding claims, characterized by that the conductive structure (2) is a sintered structure, in particular a laser sintered structure. [8] Arrangement according to one of the preceding claims, characterized by that the at least one electronic component (3) is a wireless transponder device, in particular an RFID chip, a BLE chip, one or more sensors, one or more control elements, one or more display components, in particular LEDs and / or displays, and / or a battery. [9] Arrangement according to claim 1 or 8, characterized by that the at least one electronic component (3) is connected and contacted with the conductive structure (2) via a soldered connection, an electrically conductive adhesive connection, an induction soldered connection, an induction adhesive connection and / or an ultrasonic welded connection. [10] Arrangement according to one of the preceding claims, characterized by that the textile electronic circuit is designed as a textile data carrier, in particular a textile radio data carrier. [11] Arrangement according to one of the preceding claims, characterized by that the textile electronic circuit is covered with an adhesively bonded textile cover layer (17). [12] Arrangement according to one of the preceding claims, characterized by that the at least one electronic component (3) and / or its contact is covered with a flexible housing (15a), in particular a silicone dome. [13] Arrangement according to one of the preceding claims, characterized by that the textile substrate (1) and / or the textile cover layer (17) has an outer hydrophobic coating (18). [14] Arrangement according to one of the preceding claims, characterized by that the at least one electronic component (3) has a radio interface integrated in the component. [15] Using an arrangement according to any one of the preceding claims as a wireless textile sensor device. [16] Using an arrangement according to any one of claims 1-14 as a wireless textile display device. [17] Using an arrangement according to any one of claims 1-14 as a wireless textile transponder and / or storage device.

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