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EP-4296893-B1 - CHIPLESS RFID TAG TAPE

EP4296893B1EP 4296893 B1EP4296893 B1EP 4296893B1EP-4296893-B1

Inventors

  • GAUTIER LE BOULCH, Louis

Dates

Publication Date
20260513
Application Date
20230615

Claims (20)

  1. A chipless radio frequency identification label strip, said strip comprising a dielectric substrate layer and patterned conductive material layers representing label resonators, said strip has dimensions of length L, width l and thickness Ep and is characterised in that it comprises V-shaped grooves of depth Pr of the strip and oriented in the direction of the width of the strip.
  2. Chipless radio frequency identification label strip according to claim 1, characterised in that the depth of the grooves is such that Pr > 1% of the thickness Ep of the strip, for example Pr > 5% of the thickness Ep of the strip.
  3. Chipless radio frequency identification label strip according to any one of the preceding claims, characterised in that the depth Pr of the grooves is such that Pr < 90% of the thickness Ep of the strip, for example Pr < 50% of the thickness Ep of the strip.
  4. Chipless radio frequency identification label strip according to any one of the preceding claims, characterised in that the length of the grooves is greater than 80% of the width l of the strip, for example greater than 90% of the width l of the strip, preferably identical to the width l of the strip.
  5. Chipless radio frequency identification label strip according to any one of the preceding claims, characterised in that the grooves are on both sides of the strip.
  6. Reel of chipless radio frequency identification label strip, said strip being characterised by any one of the preceding claims.
  7. Reel according to claim 6, characterised in that it comprises a central cylindrical support element for winding the strip, for example a mandrel.
  8. Reel according to claim 7, characterised in that the diameter of the central cylindrical support element "Dia" is between 25 mm and 305 mm.
  9. Reel according to any one of claims 7 and 8, characterised in that the diameter of the reel "Dreal" is between 50 mm and 1000 mm.
  10. Reel according to any one of claims 8 and 9, characterised in that the spacing between two consecutive grooves "Esp" satisfies Esp / 2 2 + Dia / 2 2 1 / 2 − Dia / 2 < 2 mm And/or Esp / 2 2 + Dreal / 2 2 1 / 2 − Dreal / 2 < 2 mm
  11. Reel according to any one of claims 8 and 9, characterised in that the spacing between two consecutive grooves "Esp" satisfies Esp / 2 2 + Dia / 2 2 1 / 2 − Dia / 2 < 1 mm And/or Esp / 2 2 + Dreal / 2 2 1 / 2 − Dreal / 2 < 1 mm
  12. Strip or reel according to any one of the preceding claims, characterised in that the distance between the grooves and the resonators and/or resonator patterns is greater than 1 mm.
  13. Strip or reel according to the preceding claim, characterised in that the distance between the grooves and the resonators and/or resonator patterns is greater than 2 mm.
  14. Strip or reel according to any one of the preceding claims, characterised in that the thickness of the dielectric substrate is greater than 0.1 mm.
  15. Strip or reel according to any one of the preceding claims, characterised in that the thickness of the dielectric substrate is less than 5 mm.
  16. Strip or reel according to any one of the preceding claims, characterised in that the dielectric substrate is selected from dielectric substrates having at least one, two or all three of the following properties: • an apparent density of less than 250 kg.m -3 ; • a relative permittivity of less than 1.25 and greater than 1.01; • a loss tangent value of less than 10 -3 .
  17. Strip or reel according to the previous claim, characterised in that the dielectric substrate has an apparent density between 25 and 75 kg.m -3 ; a relative permittivity between 1.05 and 1.09; and a loss tangent value tan δ between 10 -5 and 2.10 -4 at a frequency of 3.9 GHz.
  18. Strip or reel according to any one of the preceding claims, characterised in that the thickness of the conductive layer constituting the pattern is less than 10 microns.
  19. Strip or reel according to any one of the preceding claims, characterised in that the strip comprises a conductive layer on the face of the dielectric substrate layer opposite to that comprising the patterns consisting of a layer of conductive material.
  20. Method for preparing the strip of chipless radio frequency identification labels and/or its corresponding reel according to any one of the preceding claims by means of a roll-to-roll process that incorporates a cutting station for making the grooves.

Description

The present invention relates to a chipless (customizable) RFID tag strip, also called a "chip-less RFID tag" strip. More particularly, the invention relates to a reel of chipless (customizable) RFID tag strip. The invention also relates to a method for preparing the chipless (customizable) RFID tag strip and its corresponding reel. These labels will be advantageously included in radio frequency identification devices (known as "RFID", with "RF" denoting radio frequency) without a chip (personalized); by "device" we mean a package, a document, in particular a security document as well as possibly any object including a portion of the strip comprising at least one RFID label without a chip. Data transmission systems using radio frequency identification (RFID) technology are commonly used to identify all types of objects and living beings (e.g., animals or humans) carrying a suitable device (tag). RFID technology has become increasingly widespread over the past few decades as a device for storing and transmitting information. This RFID technology uses a radio tag, also called a transponder (from the English "transponder," a contraction of the words "transmitter" and "responder"), which is attached to an object, and a reader, also called an interrogator, to read and identify the tag. RFID technologies are generally classified into categories using "active" or "passive" tags. Active tags have a local power source (such as a battery) that they use to send a signal to the reader; they are thus generally characterized by a relatively long signal range. In contrast, passive tags do not have an internal power source because their signal transmission energy comes from the reader itself, specifically from receiving the signal emitted by the reader; thus, passive tags have a much shorter signal range, generally less than 8 meters. From a practical point of view, RFID technology uses radio frequencies (“RF”) which have much higher material penetration characteristics than signals optical. Thus, compared to barcode labels, RFID technology allows for use in much harsher environmental conditions; for example, RFID tags can be read through all kinds of materials such as paper, cardboard, wood, paint, water, dirt, dust, animal or human bodies, concrete, or even through the tagged item itself or its packaging. This has opened up a wide range of applications for RFID tags, including, for example, the identification of goods and people, particularly packaging, vehicles (parking, tolls, etc.), inventory management, electronic access cards, and all security documents such as payment methods like banknotes, checks, or meal vouchers; identity documents such as identity cards, visas, passports, or driver's licenses; lottery tickets; transportation passes; or tickets to cultural or sporting events. There are mainly two types of RFID tags, tags including an integrated electronic circuit, called chip (electronic) tags, and tags not including an integrated electronic circuit, generally referred to in the technical field by the English term "chip-less RFID tags". RFID tags (active or passive) typically include an antenna, an electronic circuit, and memory to store an identification code. The electronic circuit receives the signal emitted by the reader and, in response, transmits a modulated signal containing the identification code stored in memory within a specific frequency band. For passive RFID tags, some of the energy carried by the radio waves emitted by the reader is used to power the chip. Due to the presence of electronic circuits (such as the RFID chip or antenna component) in chip-based RFID tags, these tags have a significant production cost. It is primarily to reduce this cost that the development of chipless and antennaless tags has been proposed. This type of chipless RFID tag therefore requires neither integrated circuits nor discrete electronic components, such as transistors, inductors, capacitors, and/or antennas; this is their defining characteristic. This conductive material induces specific behavior, notably resonance. This resonance characteristic at a given frequency allows for the printing of chipless RFID tags directly onto an object at a lower cost than traditional RFID tags. Among the various families of chipless tags, they can be differentiated by the presence or absence of an RF antenna on the tag itself. Typically, as with RF systems, this antenna's role is to capture a portion of the EM wave emitted by the reader, convert it into a guided wave at the tag, and then conduct it through a filter that generates the tag's code. This filtered signal, containing the identifier ("ID"), is then retransmitted towards the reader, most often with a second antenna that performs the same function as the first but in reverse. These RFID tags have been used primarily for proof-of-concept demonstrations of chipless technology; however, their applications are very limited. The antennas are bulky and significantly increase