RFID label manufacturing process

Abstract

Title: RFID Label Manufacturing Method The invention relates to a method for manufacturing at least two narrow strips (41, 42) of RFID labels comprising: Forming a plurality of inlays (23) on a first film (11), arranged parallel to a first leading edge (11a) of the first film; Cutting the first film (11) into a plurality of formats (F) comprising N inlays (23); Rotating each format (F) 90° around a direction normal to the format (F); Forming a wide strip (30) of inlays (23) by depositing the rotated formats (F) onto a second film (12); Cutting the wide strip (30) parallel to the columns (31) so as to form at least two narrow strips (41, 42) of RFID labels (20), each having a third leading edge (41a, 42a), each RFID label (20) including an inlay (23) perpendicular to the third leading edge (41a, 42a). Figure for the abbreviation: Fig.1.

Description

Title of the invention: Method for manufacturing RFID labels technical field

[0001] The present invention relates to the production of RFID (Radio Frequency Identification) tags. Its application is particularly advantageous, for example, in the management of the distribution chain of industrial products. STATE OF THE ART

[0002] RFID tags, comprising an antenna and a chip, are widely used in various applications, from inventory management to product traceability. These RFID tags are produced by strategic manufacturing processes, ultimately resulting in RFID tag strips delivered in the form of reels or rolls with different configurations.

[0003] A commonly used configuration is the "WEL" ("Wide-Edge Leading") configuration, where the antennas are arranged on a strip so that a length of the antennas is perpendicular to the direction of strip flow and parallel to the leading edge. The chips are generally positioned on these antennas using so-called "Pick-and-Place" machines, offering efficient production. For high-volume RFID tag production, it is preferable to arrange the antennas in a WEL configuration with a small pitch between two successive antennas. Consequently, conventional Pick-and-Place machines are optimized for small pitches and large strip widths, thus facilitating strip pulling through the machine.

[0004] Another RFID tag configuration exists, known as the "NEL" ("Narrow-Edge Leading") configuration. In this configuration, the antennas are arranged parallel to the direction of the strip's feed and perpendicular to the leading edge. This configuration allows for narrow-band reels, which are advantageous for certain applications, for example, for the traceability of fine products. The pick-and-place method in this case can present challenges, notably the need to traverse the length of one antenna to move to the next, thus lengthening the manufacturing process. Furthermore, adjustments may be necessary to adapt the machines to the narrow-width strips, or to trim excess strip material at the end of the process to obtain narrow strips, which can be costly.

[0005] The present invention proposes to overcome, at least in part, the drawbacks of known methods. In particular, an objective of the present invention is to optimize the manufacturing process for narrow RFID label reels. SUMMARY

[0006] To achieve this objective, according to a first aspect of the invention, a method for manufacturing at least two narrow strips of RFID tags is provided, comprising the following steps: • A supply of a first film having a plurality of parallel antennas, arranged such that a first principal extension direction of the antennas is parallel to a first leading edge of the first film, • The formation of a plurality of antenna-chip assemblies, known as "inlays," on the first film, by depositing a chip on each of the antennas, • A division of the first film along the first direction, into a plurality of formats, each format comprising N inlays, N being a positive integer greater than or equal to 2, • A 90° rotation of each format around a direction normal to the format, • The formation of a wide strip of inlays, by depositing the filmed formats onto a second film, such that a second principal extension direction of the N inlays is perpendicular to a second leading edge of the wide strip, and that the inlays of successive formats form N columns extending along the wide strip, • A cutting of the wide strip parallel to the columns so as to form M narrow strips of RFID tags each having a third leading edge, M being a positive integer greater than or equal to 2 and less than or equal to N and each RFID tag comprising an inlay perpendicular to the third leading edge.

[0007] Format reorientation allows a series of inlays arranged in a WEL configuration to ultimately result in a series of labels arranged in a NEL configuration. This transition from a WEL to a NEL configuration during the RFID label manufacturing process makes it possible to use conventional methods and machines configured and optimized for manufacturing WEL-type RFID labels to produce labels arranged in a NEL configuration. Pick-and-place methods, for example, used to deposit chips onto antennas, are optimized for the WEL configuration. This avoids scanning the length of the antennas, which is generally greater than their width, to deposit the chips by moving from one antenna to the next, thus accelerating the manufacturing process.

[0008] Furthermore, this transition makes it possible to circumvent the constraints imposed by conventional chip deposition methods on the width of RFID tag film. Indeed, the leading edge of the antenna film that feeds a pick-and-place machine must be quite wide, preferably more than 40 mm, to ensure traction of the antenna film within the machine, which makes it difficult to manufacture a narrow RFID tag strip. The process described above resolves this constraint by deploying a WEL configuration during chip deposition onto the antennas and then reorienting the inlays to obtain RFID tags in a NEL configuration, which significantly reduces the leading edge width of the final strip.

[0009] Moreover, this process makes it possible to obtain at the end a batch of several series or strips of NEL type labels, which is not only advantageous in the context of large-scale production, but also in the context of the large-scale transfer of labels onto industrial products.

[0010] A second aspect of the invention relates to a narrow strip of RFID tags having a third leading edge, each RFID tag comprising an inlay perpendicular to the third leading edge, each inlay comprising an antenna and a chip, the narrow strip being wound in a narrow reel.

[0011] The RFID label roll is often integrated into an automatic labeling machine positioned in an industrial production line. It is generally loaded onto the machine, which ensures the automatic unwinding of the labels. The arrangement of the inlays perpendicular to the leading edge of the strip (or parallel to the direction of unwinding of the roll), as well as the reduced width of the strip, facilitates the automatic picking and unwinding of the roll. BRIEF DESCRIPTION OF THE FIGURES

[0012] The aims, objects, features and advantages of the invention will become clearer from the detailed description of an embodiment thereof, which is illustrated by the following accompanying drawings in which:

[0013] [Fig.1] Fig.1 schematically illustrates, according to an example of an embodiment, a narrow strip of RFID tags wound on a reel.

[0014] [Fig.2] [Fig.3] [Fig.4] [Fig.5] Figures 2 to 5 schematically illustrate a top view in an XY plane of the manufacturing steps of at least one narrow strip of RFID tags.

[0015] [Fig.6] Fig.6 schematically illustrates a top view in an XY plane of a manufacturing step of at least one narrow strip of RFID labels according to a first embodiment.

[0016] [Fig.7] Fig.7 schematically illustrates a top view in an XY plane of a manufacturing step of at least one narrow strip of RFID labels according to a second embodiment.

[0017] [Fig.8] Fig.8 schematically illustrates, by way of example, a longitudinal section in an XZ plane of an RFID tag.

[0018] [Fig.9] Fig.9 schematically illustrates, by way of example, a top view in an XY plane of a manufacturing step of at least one narrow strip of RFID tags.

[0019] [Fig. 10] [Fig. 11] [Fig. 12] Figures 10 to 12 schematically illustrate an example of the implementation of the manufacturing steps of at least one narrow strip of RFID labels.

[0020] [Fig. 13] Fig. 13 schematically illustrates, according to an example of an embodiment, a narrow strip of RFID tags wound in a cross-roll.

[0021] The drawings are given by way of example and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention and are not necessarily to scale with practical applications. In particular, the thicknesses and / or dimensions of the different layers, patterns and reliefs are not necessarily representative of reality. DETAILED DESCRIPTION

[0022] Before proceeding with a detailed review of embodiments of the invention, optional features that may be used in combination or alternatively are listed below:

[0023] According to one example, the narrow band has a width Wn between 0.6 mm and 750 mm.

[0024] According to one example, the format placement on the second film is configured so that the formats are aligned with each other using patterns present on the second film. The presence of these registration patterns on the second film allows for precise positioning of the formats relative to each other. This precise positioning of the formats makes it possible, on the one hand, to obtain a regular spacing between the RFID tags. On the other hand, it makes it possible to align the antennas of two successive formats, one opposite the other, in order to form regular antenna columns, which then allows for a straight cutting of the wide band parallel to the antenna columns, and the obtaining of straight narrow bands without damaging the antennas.

[0025] According to one example, the patterns may be locating marks. According to another example, the patterns may be holes or centering pins.

[0026] According to one example, the supply of a first film comprising a plurality of parallel antennas is configured such that two successive antennas are separated by a distance da greater than or equal to 2.5 mm. In the context of chip deposition onto the antennas by a Pick-and-Place method, for example, the distance da separating two successive antennas must be minimized in order to optimize manufacturing time. This distance can be reduced to as little as 2.5 mm during the step of supplying antennas arranged in a WEL configuration, which makes it possible to considerably reduce the time of this Pick-and-Place step.

[0027] According to one example, the second film on which the formats are deposited after their rotation, includes a first underlayer based on an adhesive material which allows the formats to be fixed.

[0028] According to one example, the first sub-layer of the second adhesive film surmounts a second sub-layer called the carrier layer.

[0029] According to one example, the second film may include a third underlayer based on an adhesive material, underlying the second underlayer.

[0030] According to one example, the adhesive material is based on Thermoplastic Polyurethane (“TPU” or “Thermoplastic Polyurethane” in English).

[0031] According to one example, the third sub-layer of the second film can be protected by a fourth underlying sub-layer based on silicone, for example.

[0032] According to one example, the adhesive material can be permanent or non-permanent.

[0033] According to one example, the method for manufacturing at least two narrow strips RFID tags, further includes a deposit of at least one protective layer on at least the chip of each inlay.

[0034] According to one example, the protective layer covers the chip and part of the antenna of an inlay.

[0035] According to one example, the protective layer covers the entirety of an inlay.

[0036] According to one example, several protective layers can be superimposed on at least the chip of each inlay.

[0037] This protective layer helps to protect the antennas and / or chips against mechanical damage, scratches, shocks and other external aggressions that could impair their operation.

[0038] According to one example, the protective layer is based on an adhesive material.

[0039] According to one example, the cutting of the first film and / or the wide strip is carried out at with the help of a laser beam.

[0040] According to one example, the cutting of the first film and / or the wide strip is carried out using a sharp tool.

[0041] According to one example, the manufacturing process for at least two narrow strips of RFID labels further includes laminating the wide strip with inlays.

[0042] Laminating the wide strip of inlays improves the adhesion of the formats to the first film, or of the protective layer to the inlays and improves the compactness of the wide strip of inlays.

[0043] According to one example, lamination is carried out by heating the wide strip of inlays.

[0044] According to one example, lamination is achieved by applying pressure to the strip wide range of inlays.

[0045] According to one example, the lamination of the wide strip of inlays is carried out flat by scrolling the formats one after the other.

[0046] According to one example, the lamination is carried out in a continuous manner by conveying the wide strip of inlays between heated rollers.

[0047] According to one example, the wide strip is configured so that each narrow strip of RFID tags comprises a single column of inlays. In this example, the number M of narrow strips obtained is equal to the number N of columns of inlays. The so-called "single-strand" narrow strip comprises a single series of RFID tags, which makes it possible to considerably reduce the leading edge width.

[0048] According to one example, the format deposit on the second film is configured so that every two successive antennas of the same column of inlays overlap, thus forming a continuity between the antennas of the same column.

[0049] According to one example, the format deposit on the second film is configured so that every two successive antennas of the same column of inlays are disjoint.

[0050] According to one example, each two successive antennas of the same column of inlays overlap by a few millimeters. The continuity between the antennas of a column of inlays saves adhesive material and improves the compactness of the narrow coils obtained at the end of the process.

[0051] According to one example, the method for manufacturing at least two narrow strips of RFID tags further includes ultrasonic welding of the overlapping areas between the antennas of the same column.

[0052] According to one example, the cutting of the wide strip of RFID tags is configured so that each narrow strip of RFID tags comprises at least two columns of inlays. In this example, the number M of narrow strips obtained is less than the number N of columns of inlays. The narrow strip, referred to as "multi-strand," comprises at least two RFID tags in width. Each narrow strip obtained at the end of the process undergoes a testing step, which can be costly. The greater the number of rolls, the higher the cost of this step. Manufacturing multi-strand strips reduces the costs of the testing step.

[0053] According to one example, the number N of inlays per format is between 2 and 150. According to one example, a narrow band can comprise between 2 and N columns of inlays. According to one example, a narrow band can comprise 7 or 8 columns of inlays.

[0054] According to one example, the method for manufacturing at least two narrow strips of RFID tags further comprises winding each narrow strip of RFID tags to form a narrow reel. Winding the narrow strips of RFID tags into reels facilitates the handling and delivery of the RFID tags.

[0055] According to one example, the winding of narrow strips of RFID labels into reels is carried out by overlapping.

[0056] According to one example, the winding of narrow strips to form narrow reels is achieved by crossing. In a narrow reel of RFID tags wound in overlapping order, the RFID tag chips are subjected to mechanical stress. Cross-winding allows the chips to be distributed across the width of a core, for example, thereby reducing the stress on the chips.

[0057] According to one example, each RFID tag in the narrowband has a We width between 0.6 mm and 5 mm.

[0058] These narrow RFID tags are designed to be integrated into finished products, whether in the clothing industry, pharmaceuticals (tubes, syringes), cosmetics (lipstick for example or eye pencil, etc.), or any other industrial product requiring the integration of a thin RFID tag.

[0059] According to one example, each RFID tag has a second length Le between 50 mm and 250 mm.

[0060] According to one example, each antenna in the narrowband RFID tag has a width Wa between 0.3 mm and 3 mm. According to one example, the width Wa of an antenna is equal to 1.5 mm.

[0061] It is specified that, within the framework of the present invention, the terms "on", "overcomes", "covers", "underlying", "opposite" and their equivalents do not necessarily mean "in contact with". Thus, for example, the deposit or application of a first layer on a second layer does not necessarily mean that the two layers are directly in contact with each other, but means that the first layer at least partially covers the second layer by being either directly in contact with it, or by being separated from it by at least one other layer or at least one other element.

[0062] The steps of the process are understood in the broad sense as the execution of a part of the process and may optionally be carried out in several sub-steps. Several embodiments of the invention implementing successive steps of the manufacturing process are described below. Unless explicitly stated, the adjective "successive" does not necessarily imply, although this is generally preferred, that the steps follow one another immediately; intermediate steps may separate them.

[0063] Furthermore, the term "step" does not necessarily mean that the actions carried out during a step are simultaneous or immediately successive. Certain actions of a first step may, in particular, be followed by actions related to a different step, and other actions from the first step may be repeated later. Thus, the term "step" does not necessarily imply unitary actions that are inseparable in time and in the sequence of phases of the process.

[0064] A substrate, layer, or device "based" on a material M is understood to mean a substrate, layer, or device comprising only that material M or that material M and possibly other materials.

[0065] A preferably orthonormal coordinate system, comprising the X, Y, Z axes, is shown in the accompanying figures.

[0066] Dimensional values ​​are understood to be within manufacturing and measurement tolerances.

[0067] The terms "approximately," "about," and "in the order of" mean, when referring to a value, "within 10%" of that value, or, when referring to an angular orientation, "within 10°" of that orientation. Thus, a direction substantially normal to a plane means a direction having an angle of 90+10° with respect to the plane.

[0068] It is specified that, within the framework of the present invention, the thickness of a layer or substrate is measured along a direction perpendicular to the surface along which this layer or substrate has its maximum extent. The thickness is thus taken along a direction perpendicular to the principal faces of the layer or substrate on which the different layers rest. More particularly, the thickness can be taken along the Z direction.

[0069] A narrow strip 41 wound into a reel 71 is now described with reference to [Fig.1], according to an example of an embodiment.

[0070] Figure 1 illustrates a narrow band 41 comprising at least one column 31 RFID tags 20. Each RFID tag 20 comprises an antenna 21 surmounted by a chip 22. The antennas 21, or RFID tags 20, are arranged perpendicularly to a leading edge 41a of the narrow strip. In other words, the narrow reel 41 adopts a NEL configuration. The narrow strip 41 is wound into a narrow reel 71 around a core 134. This narrow reel 71 is intended to be delivered as a finished product. The RFID tags 20 can then be applied to industrial products and configured using an RFID reader to identify and track the tagged products.

[0071] The narrow 41 strip of 20 RFID tags in the NEL configuration has a reduced width Wn. This reduced width Wn facilitates the integration of the reels into automated processing or application systems. Furthermore, Automatic handling and reel unwinding are generally simpler for a NEL configuration than for a WEL configuration. RFID 20 tags also feature a reduced We width. Since narrow RFID tags use less material, the corresponding reels can be less expensive to produce. Furthermore, narrow RFID tags can be advantageously applied to thin or small objects or products with limited labeling space. Narrow RFID 20 tags can also be more flexible and adapt more easily to curved or irregular surfaces.

[0072] The manufacturing process for such a narrow strip 41 of RFID tags is now described with reference to Figures 2 to 9. This process makes it possible to obtain in the end at least two narrow strips 41, 42, of RFID tags 20 arranged parallel to the leading edge of the strip.

[0073] As illustrated in [Fig. 2], the method comprises supplying a first film 11 having a first leading edge lia along a Y direction and a first upper surface 11b surmounted by a plurality of antennas 21. Such a film 11 including antennas can be commercially available. It can be produced by an antenna supplier using a standard process, such as, for example, the chemical etching of a metal such as aluminum bonded to a PET (polyethylene terephthalate) based film. The antennas 21 are arranged parallel to each other along the Y direction, in a WEL configuration. In other words, the antennas 21 are substantially parallel to the first leading edge lia. The antennas 21 have a width Wa and can adopt several shapes. Preferably, the antennas 21 have a straight shape with a length La greater than their width Wa.The length La of the antenna is related to the RFID frequency used, and it influences several aspects of RFID communication, such as the read range and the overall efficiency of the RFID tag 20. The antennas 21 are separated by a pitch or distance da which is preferably much smaller than the length La of the antenna 21.

[0074] The antennas 21 of the RFID tags 20 are generally made of conductive materials. These materials are chosen because of their ability to respond to the electromagnetic waves emitted by the RFID reader. The antennas 21 may, for example, be made of copper, aluminum, silver, etc. The antennas 21 may also be made of conductive ink containing metallic particles, produced by printing on the first film 11. According to other non-limiting examples, the antennas may be manufactured by processes of depositing conductive materials onto a substrate or a film. These substrates may, for example, be made of paper, or be based on polyamide, or other suitable materials.

[0075] As illustrated in [Fig. 3], a chip 22 is then deposited onto each antenna 21 to form an antenna-chip assembly known as an "inlay" 23. Each inlay 23 formed on the first film 11 constitutes an RFID tag 20. The chip 22 can preferably be a UHF (Ultra High Frequency) chip, which operates in the ultra-high frequency range, generally between 860 and 960 MHz. UHF chips are better suited to applications where the reading distance exceeds 1 meter, their range sometimes reaching up to 15 meters depending on the capabilities of the RFID reader.Other types of chips can be used, such as planar antenna compatible chips on a flexible support, such as HF (High Frequency), Bluetooth, or UWB (Ultra-Wideband) type antennas.

[0076] The formation of the inlays 23 is generally carried out using "Pick-and-Place" methods, where a first robot 80 grasps a chip 22 and positions it precisely on an antenna 21, according to the design specifications. The arrangement of the antennas 21 in a WEL configuration allows for the acceleration of the formation of the inlays 23. Indeed, during this inlay formation step, the first film 11 is conveyed in order to scan all the antennas 21. The direction of advance of the first film 11 is chosen along a direction X perpendicular to the direction Y. Since the antennas 21 are perpendicular to the direction of advance of the first film, the formation of two successive inlays 23 requires scanning the width Wa of the antenna and the distance da between two successive antennas. Since the sum Wa+ da is much less than the length La of the antenna 21, the NEL configuration advantageously accelerates the inlay formation step 23.The distance da influences the pace of this step. Thus, it is preferably minimized in order to speed up the process.

[0077] As illustrated in [Fig.4], the first film 11 is then cut along the Y direction to form a plurality of formats F. Each format F comprises N inlays 23, N being a positive integer greater than or equal to 2, and less than or equal to 150. Figures 4 and 5 illustrate a particular example in which each format F comprises N=4 inlays 23.

[0078] As illustrated in [Fig. 5], following the cutting of the first film 11 into F-formats, each F-format undergoes a 90° rotation around a Z direction perpendicular to the X and Y directions. This rotation of the F-formats allows the transition from a WEL configuration to a NEL configuration. The 90° rotated F-formats are then deposited one by one onto a second upper surface 12b of a second film 12 having a second leading edge 12a, to form a wide strip 30 of inlays 23. At this stage, the inlays 23 of the wide band 30 extend along the X direction, perpendicular to the second leading edge 12a, i.e. in NEL configuration.

[0079] The F formats are deposited successively on the second film 12 so that two inlays 23 of two successive F formats are aligned side by side along the X direction. This makes it possible to form N columns 31 of aligned inlays 23, extending along the wide band 30.

[0080] As illustrated in [Fig. 6], the wide strip 30 is cut parallel to the columns 31 along the X direction to form M narrow strips 41, 42, where M is a positive integer greater than or equal to 2 and less than or equal to N. Each narrow strip 41, 42 has a leading edge 41a, 42a and comprises at least one column 31 of inlays 23 arranged perpendicular to the leading edge 41a, 42a. The excess of the second film 12 on either side of the wide strip 30 along the Y direction can be trimmed to obtain a conforming width Wn of narrow strips 41, 42.

[0081] According to a first embodiment illustrated in [Fig. 6], the wide strip 30 of inlays 23 is cut into M=N narrow strips 4L. Each narrow strip 41 comprises a single column 31 of inlays 23, or a single RFID tag 20 per width along the X direction. This narrow strip 41 is said to be "single-strand". [Fig. 6] illustrates, in an example where N=4, the formation of 4 single-strand narrow strips 41.

[0082] Each RFID tag 20 has a width We and a length Le. According to the first embodiment, a narrow single-strand strip 41 may preferably have a width Wn equal to the width We of an RFID tag 20. This makes it possible to further reduce the width We of the narrow strip 4L

[0083] As illustrated in [Fig. 7], according to a second embodiment, the wide strip 30 can be cut into M <N bandes étroites 42, comprenant chacune au moins deux colonnes 31 d’inlays 23. Ces bandes étroites 42 dites « multibrins », comprennent chacune selon sa largeur Wn parallèle à la direction Y, au moins deux étiquettes RFID 20. Selon ce deuxième mode de réalisation, la largeur Wn de la bande étroite multibrin 42 est plus grande ou de préférence égale à la somme des largeurs We des au moins deux étiquettes RFID 20. La [Fig.7] illustre un exemple dans lequel N=4, ce qui permet d’obtenir, par exemple, deux bandes étroites multibrins 42 comprenant chacune deux étiquettes RFID 20 suivant la direction Y, et présentant une largeur Wn=2*We. Selon un autre exemple non illustré, pour N=4, une bande étroite monobrin 41 et une bande étroite multibrin 42 comprenant 3 colonnes 31 d’inlays, peuvent être obtenues.According to another example, a narrow multistrand 42 band can include a number of columns 31 of inlays up to 150 columns 31. Preferably, each narrow multistrand 42 band can include 7 or 8 columns 31 of inlays 23.

[0084] Figure 8 illustrates a longitudinal section of an RFID tag 20 in an XZ plane. According to the example shown in Figure 8, the second film 12, onto which the F formats are deposited after rotation, may include a first sublayer 121 based on an adhesive material. The adhesive material allows the F formats to be fixed to the second upper surface 12b of the second film 12, thus maintaining good alignment of successive F formats during the subsequent steps of the process. This first adhesive sublayer 121 may be supported by a second sublayer 122, referred to as the "carrier" sublayer. The second sublayer 122 is generally based on a non-adhesive material, such as silicone. An RFID tag 20 with a non-adhesive lower surface is known as a "dry inlay."

[0085] The second film 12 may further comprise a third sublayer 123 based on an adhesive material, underlying the second or carrier sublayer 122. This third adhesive sublayer 123 allows the RFID tag 20 to be affixed to a product surface, for example. An RFID tag 20 comprising an adhesive underside, i.e., a third adhesive sublayer 123, is known as a "wet inlay." This type of RFID tag constitutes a finished product ready for application.

[0086] The third adhesive underlayer 123 can be protected by a fourth underlayer 124, called a "liner" or "release liner," or simply a coating. This fourth underlayer 124 serves to protect the adhesive until the RFID tag 20 is applied to a surface. It is generally designed to be easily removed before the RFID tag 20 is applied.

[0087] The first and third adhesive sub-layers 121, 123 may be based on the same adhesive material, or on different adhesive materials with different adhesion properties. For example, the adhesive material of the first sub-layer 121 may be permanent, allowing the F-formats to be permanently fixed to the second film 12. The first sub-layer 121 may be based on a non-permanent adhesive material, allowing the F-formats or the RFID tags 20 to be removed or repositioned without leaving any sticky residue. The third sub-layer 123 may be based on a permanent adhesive material, allowing the RFID tag 20 to be affixed to a surface in such a way that it is difficult to remove without damaging the surface.The third underlayer 123 can also be based on a pressure-sensitive, non-permanent adhesive material, allowing the RFID 20 label to be easily removed without damaging the product surface, thus enabling the RFID 20 label to be reused, for example.

[0088] An adhesive material may, for example, be of the "Hot Melt" type, or thermofusible, which is activated by heat and solidifies upon cooling. This type Adhesive is used for applications requiring rapid adhesion. Thus, the first underlayer 121 can be based on a hot melt adhesive, for example based on Thermoplastic Polyurethane (“TPU” or “Thermoplastic Polyurethane” in English).

[0089] The method may further include depositing a protective layer 60 on the inlays 23 of the wideband 30. This protective layer 60 encapsulates the antenna 21 and / or the chip 22 of an RFID tag 20, thereby improving their robustness against mechanical damage, scratches, impacts, and other external aggressions that could impair their operation. The protective layer 60 is configured to at least encapsulate the chip 22, which may have a reduced thickness on the order of one hundred micrometers, for example, around 130 µm. It may also encapsulate part of the antenna 21, or the entire antenna 21, as illustrated in [Fig. 8]. Several protective layers can be applied to further enhance the robustness of the inlays. The protective layer can be based on a plastic material or an epoxy resin. Preferably, the protective layer can be based on an adhesive material.In a non-limiting manner, other additional layers, not illustrated, may be added above inlay 23, or below inlay 23.

[0090] The process may further include a step of laminating the wide strip 30 of inlays 23. Laminating the wide strip 30 of inlays improves the adhesion of the F-shaped inlays to the second film 12. Lamination can be performed under pressure to improve the adhesion of the F-shaped inlays to the second film 12. Lamination can also be performed under heat, particularly when a first underlayer 121 based on a hot-melt adhesive is present, in order to activate the latter. It can be performed in the presence of the patient. The F-shaped inlays can also simply be brought into contact with other adhesive materials without the need for heat. Lamination can also be performed after the application of the protective layer 60 to improve its adhesion to the inlays 23.

[0091] Figure 5 illustrates an example in which the F formats are arranged on the second film so that successive antennas 21 in the same column are separated from each other. Figure 9 illustrates another example, which presents an alternative approach to fixing the F formats on the second film 12, without necessarily using an adhesive material. In this example, successive F formats are deposited on the second film 12 so that the antennas 21 in the same column 31 of inlays 23 are in contact, thus forming a continuity between the antennas 21 in the same column 31. Two successive antennas 21 in the same column 31 may, for example, overlap by a few millimeters. According to this example, the process may further include an additional soldering step that allows the Antennas 21 are brought into contact. Preferably, the welding is performed ultrasonically. Welding ensures continuity between the inlays 23 of the wideband 30 without the need for an adhesive material. This saves adhesive material, thus reducing costs in mass production. The second film 12 can be PET-based. It can also be made of weldable materials (ultrasonic or otherwise), while being relatively insensitive to tensile stress, in other words, having little or no elongation. Furthermore, according to this example, the final length of the wideband 30, and consequently that of a narrowband, is considerably reduced, which improves the compactness of the narrow reels obtained at the end of the process. This example is particularly advantageous in the case of manufacturing 4L single-strand narrowbands.

[0092] Figures 10 to 12 illustrate examples of implementation of the steps in the RFID label manufacturing process 20.

[0093] As illustrated in [Fig. 10], the step of forming inlays 23 by depositing a chip 22 onto each antenna 21 can be carried out using a machine 100 known as a "roll-to-roll" machine. The operating principle of a roll-to-roll machine 100 is based on the continuous processing of a flexible film that is unwound from an initial reel, passes through various processing stages along a feed direction A parallel to the X direction, and is then wound onto a new reel. In the example illustrated in [Fig. 10], the initial reel corresponds to the first film 11, presenting a plurality of antennas 21 arranged in a WEL configuration, or perpendicular to the feed direction A of the roll-to-roll machine 100.

[0094] The first film 11 is placed on a first unwinding mandrel 131. The first film 11 is then unwound and conveyed along the forward direction A by means of a conveyor system. The conveyor system may include, for example, rollers 110, belts, or other mechanisms to keep the film moving continuously and regularly. It may also include a table 120 placed under vacuum, which keeps the upper surface 11b of the first film 11 in place and flat along its path. As the first film 11 unwinds, a first pick-and-place robot 80 grasps a chip 22 and precisely positions it on an antenna 21, and then on the next, in order to form a plurality of inlays 23. The smaller the distance da separating two successive antennas 21, the faster this inlay 23 formation step. The distance da can be reduced to as little as 2.5 mm.This minimum distance, da, is wide enough to form an F-shaped edge between two successive antennas without damaging either antenna.

[0095] Once the chips 22 are correctly positioned and fixed onto the antennas 21, the first film 11 of inlays 23 can continue its journey on the table below The first inlay film 11 can be wound onto a second mandrel 132 to form an intermediate roll, which will then be unwound on another machine, for example. The first inlay film 23 is then cut along the extension direction of the antennas 21, parallel to the Y direction, to form F-shaped formats, preferably of identical dimensions, each comprising N inlays 23. This cutting step, not shown, can be performed mechanically using a cutting tool 103 or with a laser beam.

[0096] Figure 11 illustrates, by way of example, the step of forming the wide strip 30 of inlays. A second film 12 is unwound on a roll-to-roll machine 100. The second film 12, comprising a first underlayer 121 based on an adhesive material, passes under a heating element 104, which serves to locally preheat the second upper surface 12b of the second film 12 to activate the adhesive material. The heating element 104 can be, for example, a hot air source or an infrared radiation source.

[0097] Once the second upper surface 12b is activated, it is conveyed to a second robot 81. The second robot 81 rotates each F format by 90°, aligns it, and places it onto the activated second upper surface 12b. The F formats are aligned to form a wide strip 30 with N columns 31 of inlays 23 arranged parallel to the direction of travel of the second film 12. The width of the second film 12 along the Y direction can be greater than or equal to that of the F formats. The excess of the second film 12 on either side of the wide strip 30 along the Y direction can subsequently be trimmed.

[0098] The second robot 81 is advantageously equipped with at least one camera to ensure proper alignment of the F-formats. To improve the accuracy of the F-format alignment, the second film 12 can have registration marks 50. This precise positioning of the F-formats allows, on the one hand, for a regular spacing between two successive F-formats. On the other hand, it allows the antennas 21 of two successive F-formats to be aligned opposite each other, in order to form regular columns 31. The marks 50 can be, for example, registration marks, holes, or centering pins. The second robot 81 can also be a Pick-and-Place robot. The example illustrated in [Fig. 11] is an example of manufacturing disjoint inlays that adhere to the second film 12 cold, which are then pressed between two rollers or plates on the second film.According to the example in which the antennas 21 of two successive formats are in contact, the wideband 30 can then be routed to an ultrasonic welder 90, in order to weld the overlapping antennas.

[0099] The wide strip 30 of inlays can then undergo a lamination step. The lamination of the wide strip 30 of inlays 23 can be carried out flat by passing the formats F one after the other under a lamination machine 105. According to another example, the lamination can be carried out continuously by conveying the wide strip 30 of inlays 23 between heated rollers. Following lamination, the wide strip 30 can, for example, be wound onto a third mandrel 133 or can continue its path to another processing step.

[0100] Figure 12 illustrates, by way of example, the step of forming a plurality of narrow strips 41, 42, of RFID tags 20, by cutting the wide strip 30 of inlays 23. The wide strip 30 is unwound onto the third mandrel 133 and conveyed by a roll-to-roll machine 100 to at least one cutting tool 103 in order to be cut along the length of the columns 31 parallel to the feed direction A of the machine 100. According to an example not shown, the wide strip 30 can be cut using a laser beam. Separate narrow strips 41, 42 of RFID tags 20 can thus be obtained. Figure 12 illustrates an example in which one multi-strand narrow strip 42 and two single-strand narrow strips 41 are produced.Other combinations are also possible, such as a multi-strand reel 42 with three RFID tags 20 across and a narrow single-strand strip 4L. The narrow strips 41, 42 can then each be wound onto a fourth core 134 to form narrow reels 71, 72. The excess of the second film 12 on either side of the wide strip 30 along the Y direction can also be cut off.

[0101] The winding of the narrow strips 41, 42 can be carried out in various ways. The narrow strip 41, 42 can be wound by overlapping, by winding the narrow strip 41, 42 in successive layers one above the other, as illustrated in [Fig. 1]. According to another example illustrated in [Fig. 13], the narrow strip 41, 42 can be wound by constant pitch cross-winding. In cross-winding, the successive layers of the narrow strip 41, 42 are arranged in a crossed rather than overlapping manner. In this winding, the narrow strip 41, 42 is wound around a core or a fourth mandrel 134, forming alternating crossings between the successive layers. By crossing the layers, we reduce the internal stresses of the narrow band 41, 42, which can help to improve dimensional stability and minimize deformations.Thus, cross-winding reduces the mechanical stress on the chips 22 of the RFID tags 20.

[0102] The narrow strips 41, 42, wound onto reels 71, 72, are intended to be delivered as finished products. The width Wn of a narrow strip can be between 0.6 mm and 750 mm. The width We of an RFID tag 20 can be between 0.6 mm and 5 mm. The width Wa of an antenna 21 can be between 0.3 mm and 3 mm, preferably equal to 1.5 mm. The length La of an antenna 21 can be between 40 mm and 240 mm, and the length Le of an RFID tag 20 can be between 50 mm and 250 mm.

[0103] In view of the foregoing description, it is clear that the proposed method offers a particularly efficient solution for manufacturing narrow RFID label strips in a NEL configuration. This solution is also advantageously compatible with conventional RFID label manufacturing machines.

[0104] The invention is not limited to the embodiments described above and extends to all embodiments covered by the invention. Various specific examples of manufacturing processes and configurations of narrow RFID tag strips have been described. Many other embodiments are possible, for example, by combining features described above, without departing from the scope of the invention. Furthermore, the features described with respect to one aspect of the invention can be combined with another aspect of the invention.

[0105] The invention offers various applications in the clothing industry for improved inventory management, in the pharmaceutical sector for tracking tubes and syringes, and in the cosmetics industry for products such as eyeliners. It can also be integrated into any industry requiring the use of a thin label. It is important to emphasize that these applications are not limited exclusively to RFID tags, but can also include long, thin sensors, thus expanding the possibilities for using the method described above.

Claims

Demands

1. A method for manufacturing at least two narrow strips (41, 42) of RFID tags (20) comprising the following steps: • supplying a first film (11) having a plurality of parallel antennas (21) arranged such that a first principal extension direction of the antennas (21) is parallel to a first leading edge (1a) of the first wire m(ll), • forming a plurality of antenna-chip assemblies called "inlays" (23) on the first film (11), by depositing a chip (22) on each of the antennas (21), • cutting the first film (11) along the first direction, into a plurality of formats (F), each format (F) comprising N inlays (23), N being a positive integer greater than or equal to 2, • rotating each format (F) by 90° around a direction normal to format (F), • a formation of a wide strip (30) of inlays (23), by depositing the formats (F) shot on a second film (12),so that a second principal extension direction of the N inlays (23) is perpendicular to a second leading edge (12a) of the wide strip (30), and that the inlays (23) of successive formats (F) form N columns (31) extending along the wide strip (30), • a cutting of the wide strip (30) parallel to the columns (31) so as to form M narrow strips (41, 42) of RFID tags (20) each having a third leading edge (41a, 42a), M being a positive integer greater than or equal to 2 and less than or equal to N and each RFID tag (20) comprising an inlay (23) perpendicular to the third leading edge (41a, 42a).

2. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to the preceding claim wherein, the deposition of the formats (F) on the second film (12) is configured so that the formats (F) are aligned with each other using patterns (50) present on the second film (12).

3. A method for manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to any one of the preceding claims, wherein the supply of a first film (11) comprising a plurality of parallel antennas (21) is configured such that two successive antennas (21) are separated by a distance da greater than or equal to 2.5 mm.

4. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to any one of the preceding claims, wherein the second film (12) on which the formats (F) are deposited after their rotation, comprises a first underlayer (121) based on an adhesive material which allows the fixing of the formats (F).

5. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to any one of the preceding claims, further comprising a deposit of at least one protective layer (60) on at least the chip (22) of each inlay (23).

6. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to any one of the preceding claims, further comprising laminating the wide strip (30) with inlays (23).

7. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to any one of the preceding claims, wherein the deposition of the formats (F) on the second film (12) is configured so that every two successive antennas (21) of the same column (31) of inlays (23) are disjoint.

8. Method of manufacturing at least two narrow strips (41) of RFID tags (20) according to any one of the preceding claims, wherein the cutting of the wide strip (30) is configured so that each narrow strip (41) of RFID tags (20) comprises a single column (31) of inlays (23).

9. Method of manufacturing at least two narrow strips (41) of RFID tags (20) according to the preceding claim, wherein the deposition of the formats (F) on the second film (12) is configured so that every two successive antennas (21) of the same column (31) of inlays (23) overlap, thus forming a continuity between the antennas (21) of the same column (31).

10. Method for manufacturing at least two narrow strips (41) of RFID tags (20) according to the preceding claim, including further ultrasonic welding of the overlapping areas between the antennas (21) of the same column (31).

11. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to any one of claims 1 to 7, wherein the cutting of the wide strip (30) of RFID tags (20) is configured so that each narrow strip (42) of RFID tags (20) comprises at least two columns (31) of inlays (23).

12. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to any one of the preceding claims, further comprising winding each narrow strip (41, 42) of RFID tags to form a narrow reel (71, 72).

13. Method of manufacturing at least two narrow strips (41, 42) of RFID tags (20) according to the preceding claim, wherein the winding of the narrow strips (41, 42) to form narrow reels (71, 72) is carried out by crossing.

14. Narrow strip (41, 42) of RFID tags (20) having a third leading edge (41a, 42b), each RFID tag (20) comprising an "inlay" (23) perpendicular to the third leading edge (41a, 42a), each inlay (23) comprising an antenna (21) and a chip (22), the narrow strip (41, 42) being wound into a narrow reel (71, 72).

15. Narrow strip (41, 42) of RFID tags (20) according to the preceding claim, wherein each RFID tag (20) has a width We between 0.6 mm and 5 mm.

16. Narrow strip (41, 42) of RFID tags (20) according to any one of the two preceding claims, wherein each antenna (21) has a width Wa between 0.3 mm and 3 mm, preferably equal to 1.5 mm.

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