HK1149352B - Radiofrequency identification device for passport and method for making same - Google Patents

Description

RFID device support for passports and method of making same

Technical Field

The present invention relates to radio frequency identification devices for integration into objects such as security documents, and in particular to radio frequency identification device supports for passports and methods of making the same.

Background

Contactless Radio Frequency Identification Devices (RFID) are increasingly used to identify people moving within a controlled proximity zone or from one zone to another. A contactless RFID device is a device made of an antenna and a chip connected to a terminal of the antenna. The chip is normally not powered and receives its energy through electromagnetic coupling between the antenna of the reader and the antenna of the RFID, information being exchanged between the RFID and the reader, in particular information stored in the chip relating to the identification of the holder of the object on which the RFID is placed and his/her authorization to enter into the controlled access area.

As such, the passport may include an RFID that identifies the passport holder. The chip memory contains information such as the identity of the passport holder, his/her country of birth, his/her nationality, visas of different countries visited, date of entry, activity restrictions, biometric elements, etc. .

Generally, the RFID device may also be manufactured separately from the passport, for example, to then be added by gluing between the front and back white sheets of the passport. The RFID device, including the antenna and chip connected together, is then integrated with a support made of paper, plastic or other (generally referred to as an "inlay").

These supports typically comprise at least two rigid layers with an RFID device interposed therebetween. A disadvantage of such supports is their lack of flexibility due to their multi-layer structure.

Disclosure of Invention

It is therefore an object of the present invention to remedy these drawbacks by providing an RFID device which is incorporated in an identity document such as a passport, which has good flexibility properties while ensuring a reliable connection between the integrated circuit module and the antenna.

It is a further object of the invention to provide an identity document such as a passport incorporating such a radio frequency identification device, without any visible marking of the chip on the outside of the cover of the document.

The object of the present invention is therefore a method for manufacturing a cover for an identity document having a Radio Frequency Identification Device (RFID), said device comprising an antenna and a chip connected to the antenna, said method comprising the steps of:

-realizing an antenna with connection points on a paper or synthetic paper support;

-creating a cavity between the connection points of the antennas;

-placing an adhesive dielectric material on the antenna support in the vicinity of the antenna connection point;

-positioning an integrated circuit module on the support, the module comprising a contact area and a chip connected to the contact area within the package, such that the contact area of the module is opposite to the connection point of the antenna and the package of the module is located in the cavity;

-placing at least one layer of thermal adhesive film on the face of the support comprising the antenna;

-placing a cover layer on the thermal adhesive film layer(s);

-laminating the support layer, the thermal adhesive film layer and the cover layer together.

Drawings

The objects, objects and features of the present invention will become more apparent from the following description when read in conjunction with the accompanying drawings, in which,

FIG. 1 shows a top view of an antenna support and antenna of an RFID device according to the present invention;

fig. 2 shows an antenna support and an integrated circuit module according to section D-D in fig. 1;

FIG. 3 shows a top view of an antenna support and antenna of an RFID device according to a variation of the present invention;

fig. 4 shows an antenna support and an integrated circuit module according to section D-D in fig. 3;

FIG. 5 shows a cross-section of the layers that make up an electronic cover in accordance with the invention in a first embodiment;

FIG. 6 shows a cross-section of the layers making up an electronic cover in accordance with a second embodiment of the invention;

FIG. 7 shows a cross-section of an RFID device support after lamination;

FIG. 8 shows a cross-sectional view of the layers making up the RFID device support according to a first embodiment of a variation of the present invention;

FIG. 9 shows a cross-sectional view of the layers making up the RFID device support according to a first embodiment of a variation of the present invention;

FIG. 10 shows a cross-sectional view of an RFID device support after a first lamination step according to a variation of the present invention;

FIG. 11 shows a cross-sectional view of the layers making up an RFID device support according to a variation of the present invention;

FIG. 12 shows two RFID device supports and a cover for an identity document according to the present invention.

Detailed Description

According to a first step of the present manufacturing method, an antenna is realized on the support layer 10. The antenna comprises a set of one or more coils 12. The coils are made by screen printing, flexographic offset printing, gravure printing, offset printing or ink jet printing using conductive inks of the epoxy type or based on conductive polymers, to which conductive particles such as, for example, silver or gold are added. The support layer 10 is made of a material such as paper or synthetic paper. The paper is made of pulp micro-plant fibers and as a result has a fibrous structure. Paper core (du papier) tends to delaminate when subjected to shear stress, whereas non-fibrous synthetic papers have a microporous structure and have a low density. Similar to paper, synthetic paper simplifies the layering operation performed at temperatures on the order of 160 ℃, since it is stable at these temperatures; unlike thermoplastic materials such as PVC or PETG, it does not flow (fluent). The synthetic paper used consists of a non-oriented single layer of a polymer such as polyethylene or polypropylene with between 40% and 80% mineral addition. By its microporous network, its composition is such that it has a value of 0.57g/cm3Low density of (2). The thickness of the support layer is between 240 and 280 μm and preferably 250 μm. The support 10 comprises a hollowed-out portion 11 corresponding to the position of the hinge (joint) of the identity document.

According to fig. 2, the integrated circuit module 19 comprises a chip 35, at least two connection regions 33 and 34. The connection between the chip and the connection regions 33 and 34 is realized by means of very small wires or connection cables, which are called "wire bonding". The chip 35 and the wires are encapsulated in a protective resin 37 based on a non-conductive, highly resistant material. The package 37 is in a sense a hard shell containing the chip and its wiring so that it is less prone to damage and easier to handle. The package has a degree between 200 and 240 μm. The module thus presents a flat surface on its upper side, corresponding to the upper part of the package 37, and contact areas 33 and 34 for connection with the circuit on its lower side. The contact regions 33 and 34 are made of an electrically conductive material, such as aluminum, and their thickness is between 70 and 100 μm.

The module 19 shown in fig. 2 is intended to be connected to an antenna connection point of an antenna. In the present invention, only two connection points 13 and 14 are sufficient for connecting the modules. The connection points 13 and 14 are a continuum of the antenna. As a result, they are in extension of the coil of the antenna and are generally made of the same material as the antenna. The connection points are thus also made by screen printing, flexographic offset printing, gravure printing, offset printing or ink-jet printing with conductive inks based on the type of epoxy ink to which conductive particles such as, for example, silver or gold are added or based on conductive polymers. The thickness of the connection point is between 5 and 10 μm.

According to a variant of the invention shown in figures 3 and 4, the mooring positions on the supporting layer are produced with a thickness of between 10 and 50 μm. The step of creating the parking position (embossage) consists in compressing a portion of the supporting layer 10 by pressing, so that it thus retains the pressed cavity (embrointe). The form of pressing used is such that it leaves a rectangular cavity 17 slightly larger than the module. The step of producing a parking position is done before the antenna is implemented. All the following steps remain unchanged with respect to the method without producing a parking position and, in particular, the following description of the steps of positioning the modules is the same. The thickness of the support layer 10 in this case is preferably equal to 300 μm.

The module 19 is glued to the antenna support layer 10 by means of two spots 25 and 26 of adhesive material on the side of the antenna connection points so that the connection points 13 and 14 of the antenna are opposite the contact areas 33 and 34 of the module and so that the encapsulated part or encapsulation 37 of the module is in the cavity 20. And, in particular, the connection points 13 and 14 are opposite to the portions of the contact zones 33 and 34 not covered with adhesive material. The adhesive material for the spots 25 and 26 is an adhesive that only secures the module to the support layer 10 and, since the adhesive is non-conductive, it does not directly participate in the electrical connection between the module and the antenna. The adhesive used was a cyanoacrylate adhesive. The adhesive spots are arranged on the support layer 10 in the vicinity of the antenna connection spots such that when the module 19 is mounted in the cavity 20, the adhesive of the contacts is pressed by the contact areas of the module until they come into contact with the antenna connection spots. The adhesive dots thereby attain the same or substantially the same thickness as the antenna connection points and become flush with the antenna connection points. The proximity of the adhesive dots to the antenna connection points ensures the reliability of the electrical connection. Thus, once the module 19 is seated in the cavity 20, an electrical connection is made through the portions in contact with the contact areas of the module and the connection points 13 and 14 of the antenna. The support thus obtained is an antenna support fitted with a module integral with the support and electrically connected to the antenna. Preferably, the antenna connection point has a pit or dimple shape or is hollowed out in a circular manner such that the viscous material point is placed in a recessed or hollow portion of the pit shape. In a preferred embodiment of the invention, the antenna connection point has a U-shape, so that the spot of adhesive material is placed inside the U and is thereby almost completely surrounded by the antenna connection point. Thus, the electrical connection has the advantage that it is achieved without soldering and without bringing about material.

The next step of the method is shown in fig. 5 and 6, according to two different modes. In a first embodiment, and referring to fig. 5, a layer of thermal adhesive film 40 is placed directly on the antenna side of the antenna support and the underside of the module. The second layer 70 is placed directly on the thermal adhesive film layer 40. This layer corresponds to the cover of the identity document and has a thickness of about 350 μm. The facing layer 70 has a paper or textured substrate covered by a layer of polyester. It may contain specific particles on its free surface 72 that make it resistant to damage. However, it is also possible to subject the free surface of the cover of the document to a plate with special bumps during or after lamination to produce specific particles on the cover.

In a second embodiment of the present invention, and with reference to fig. 6, a thermal adhesive film 50 is placed directly on the antenna side on the antenna support and on the lower part of the module. Layer 50 has a cavity 52 with dimensions close to the dimensions of the entire surface of the module. In this way, the edges of the cavity 52 match the outside edges of the module containing the contact areas. Thus, when the layer 50 is placed on the antenna support layer 10, the module 19 is located in the cavity 52. The second layer 60 is located on the first layer 5. Layer 60 is also a thermal adhesive film that preferably has the same properties as layer 50 and does not have any cavities. Layer 70 is located on the thermal adhesive film layer 60. The adhesive properties of the thermal adhesive film layers 40, 50 and 60 are activated by the application of heat. These layers each have a thickness of about 50 μm.

The first embodiment, corresponding to a single layer of hot adhesive 40, is more suitable for the case where the support layer 10 is brought into a parking position in the position of the module according to figures 3 and 4. In this case, in fact, the contact zones of the modules are partially or completely buried in the thickness of the support layer 10 and, as a result, only one layer of thermal adhesive is sufficient to eliminate the projections due to the modules. The second embodiment with two thermal adhesive layers 50 and 60 is more suitable for the case where the support layer is not brought into a parking position. However, this preference is not limiting.

The layers, which are indicated with 10, 40 and 70 in the case of the first embodiment and with 10, 50, 60 and 70 in the case of the second embodiment, are assembled to one another by lamination. The lamination step comprises subjecting all the layers to a temperature increase of up to 150 ℃ and up to 0.5 to several bars (about 10N/m)²) Then the temperature and pressure are reduced, throughout the cycle according to a set of defined durations.Upon lamination, the thermal adhesive film of the first example layer 40 and the thermal adhesive films of the second example layers 50 and 60 fluidize and capture a majority of the antenna and module. The pressure exerted during lamination is perpendicular to the layers and thus to the contact surfaces of the contact areas 33 and 34 of the module and the connection points 13 and 14 of the antenna.

Figure 7 shows a cross section of the module and 3 different material layers after the lamination step. During the lamination step, the thickness of the layers making up the RFID device support is reduced. In this way, the total thickness of the layers before lamination amounts to 680 μm, which corresponds in detail to the following distribution:

-a cover 70: 350 μm;

two thermal adhesive films of 40 μm;

-a support layer 10: 250 μm.

After lamination, the sandwich structure obtained, which is referred to in the following description as electronic cover, has a thickness between 640 μm and 650 μm.

Pressure is applied to the entire module during lamination. The contact areas of the module press on the connection points of the antenna, resulting in a deformation of the connection points and the support layer 10. This deformation is in the form of a cavity (impression), the inner surface of which exactly matches the outer surface of the connecting zone. In this way there is a close contact on the largest contact surface between the connection areas 33 and 34 of the module and the conductive ink of the connection points 13 and 14. The material constituting the support layer 10 and the conductive ink of the connection points 18 are deformable and inelastic, so that both materials do not tend to return to their original shape even when the pressure is released.

Also, upon lamination, the thermal adhesive film of layers 40 or 50 and 60 softens and closely matches the contour of the interior face of the module. The thermal adhesive film of layers 40 or 50 and 60 acts as an adhesive between the facing layer 70 and the antenna support layer 10 so that once hardened it adheres completely to both layers and the module. The two layers 10 and 70 on either side of the thermoplastic layer are stressed by the pressure in the lamination and the applied stress is maintained on the contact areas of the module so that once the thermal adhesive film of the layers 40 or 50 and 60 is hardened, the electrical contact between the module and the antenna is permanent and reliable.

Another embodiment method of the present invention, illustrated in fig. 6-9, is to implement the first pre-lamination step with the layers making up the support of the RFID device but without the facing layer 70. The lamination consists in partially activating the layer 40 or the layers 50 and 60 of the thermal adhesive film in order to "glue" them to the antenna support 10 and to maintain the possibility of being able to activate it (or activate them) again in another lamination step. The pre-lamination step consists in subjecting all the layers to a temperature increase, up to a maximum temperature between 50 ℃ and 70 ℃ and holding for 3 minutes, and increasing the pressure. Upon pre-lamination, the thermal adhesive film of layer 40 of the first example of fig. 8 and the thermal adhesive films of layers 50 and 60 of the second example of fig. 9 fluidize and capture most of the antenna and module. The support of the RFID device 51 obtained after this pre-lamination step is an antenna support provided with an electronic module connected to the antenna. The support of the RFID device 51 comprises the layer 10 of antenna support and the layer 53 of thermal adhesive corresponding to the initial layer 40 or the initial layers 50 and 60 of thermal adhesive film. Layer 80 is disposed on thermal adhesive film layer 53. The adhesive property of the thermal adhesive film layer 53 is reactivated by the application of heat. Thus, the layers 10, 53 and 80 are assembled to each other by lamination. The lamination step is similar to that previously described in FIGS. 5-7. Similarly, when the thermal adhesive film of layer 53 is hardened, the electrical contact between the module and the antenna is permanent and reliable.

Figure 12 shows a top view of a support 100 provided as a cover with an RFID device to be used as a complete identity document. It includes a cover layer 90 having a width greater than the width of the identity document and may comprise a length supported by a plurality of RFID devices according to the present invention. We can also see the layer 92 corresponding to the paper or composite paper antenna support layer and the module ensemble 19 visible in the cavity 20 of the layer 92. The cut-out position of the cover of the identity document is indicated by the dashed line in the figure. The identity document is then completely formed by installing a blank sheet.

The manufacturing method according to the invention provides a reliable and robust radio frequency identification device. Also, the particles of the cover are not damaged in the laminating step.

Claims (9)

1. A method for manufacturing a cover for an identity document having a Radio Frequency Identification Device (RFID), the device comprising an antenna and a chip (12) connected to the antenna, the method comprising the steps of:

-realizing an antenna (12) with connection points (13 and 14) on a support layer (10) made of paper or synthetic paper;

-creating a cavity (20) between the connection points (13 and 14) of the antenna;

-placing an adhesive dielectric material (25, 26) on the support layer (10) in the vicinity of the connection point of the antenna, the connection point of the antenna having a pit or dimple shape or being hollowed out in an annular manner, such that the point of the adhesive dielectric material is placed in the recess or hollowed out portion formed by the pit shape;

-positioning an integrated circuit module (19) on the support layer, the integrated circuit module comprising contact areas (33, 34) and a chip connected to the contact areas within a package (37), such that the contact areas of the integrated circuit module are opposite the connection points of the antenna and the package of the integrated circuit module is located in the cavity (20);

-placing at least one thermal adhesive film (40, 50, 60) on the face of said support layer comprising the antenna;

-placing a cover layer (70) on the thermal adhesive film layer(s) (40 or 50 and 60);

-laminating together a support layer (10), the thermal adhesive film layer (40 or 50 and 60) and a cover layer (70).

2. Method according to claim 1, wherein the preliminary step of the antenna realisation step consists in creating a parking position of a portion of said supporting layer (10) at the location of the integrated circuit module with a thickness between 50 and 60 μm, the parking position thus created having a slightly larger shape than the integrated circuit module.

3. Method according to claim 1 or 2, characterized in that the thermal adhesive film layer applied directly to the support layer (10) has cavities (20) at the location of the integrated circuit modules (19), the shape of the cavities (20) being such that it matches the edges of the lower surface of said integrated circuit modules.

4. A method according to claim 3, wherein the adhesive dielectric material (25, 26) placed on the support layer (10) is a cyanoacrylate adhesive.

5. A method according to claim 1 or 2, wherein the connection point of the antenna is U-shaped and an adhesive dielectric material is provided within the U-shape.

6. A method according to claim 1 or 2, wherein the synthetic paper of the support layer (10) is made of a material which does not flow, i.e. deform, when the temperature rises.

7. The method according to claim 1 or 2, wherein said thermal adhesive film layer has a thickness of 50 μm.

8. Method according to claim 1 or 2, wherein the antenna (12) is made by screen printing based on conductive ink.

9. A radio frequency identification device, characterized in that it is obtained by a method according to any one of the preceding claims.