Radio frequency identification device medium and method for making same

Translation of description of equivalent WO 2007125214 A2

p0001Support radio frequency identification device and its manufacturing method

p0002Technical Field The present invention relates to devices for identifying radio frequency to be integrated into objects such as security documents and relates in particular to support device identification radiofrequency and its manufacturing process.

PRIOR ART

p0004The radio frequency identification devices (RFID) contactless are increasingly used for identification of persons moving about in controlled access zones or transiting from one zone to another. A contactless RFID device is a device comprising an antenna and a chip connected to the antenna terminals. The chip is usually not powered and receives its energy by electromagnetic coupling between the reader antenna and the antenna of the RFID device, information is exchanged between the RFID device and the reader and particularly information stored in the chip relating to the identification of the owner of the object on which is the RFID device and its authorization to enter into a controlled access area.

p0005Thus, passports can incorporate RFIDs to identify the passport holder. The chip memory contains information such as the identity of the passport holder, his country of origin, nationality, visas of different countries visited, dates of entry, restrictions of movements, biometric elements, etc. . The RFID device is generally incorporated in the bottom of the passport cover dish. An antenna is then carried out by screen printing ink loaded with silver particles on the lower flat reinforced the passport cover. The chip is then connected by sticking to the antenna terminals. Then the flyleaf of the quire of passport pages is laminated to the back of the reinforced top cover. This embodiment has the disadvantage of not withstand the test of the water and in particular the passage of passport washing machine. Indeed, if the paper is screen printed antenna is not water resistant, the latter absorbs water and swells, causing fractures to the antenna and therefore a rupture electrical connection between the antenna and the chip.

p0006This problem can be overcome by using an RFID device composed of a "inlay" plastic. In this case, the inlay comprises the antenna and the chip, the whole being embedded in a plastic coating. The inlay is then transferred by bonding between the cover page and the passport cover. One of the drawbacks of this type of RFID device based on the difference material between the inlay and the passport. The latter being made of plastic, the bonding between the two is not optimum. The use of an RFID carrier with at least one of its external faces by paper overcomes this drawback.

p0007But the problem of the use of paper based on its characteristic to delaminate in its thickness in case of attempt of pulling. Delamination can also be done on the edges of the support from a certain period of use, which presents some disadvantages when the support is intended to be used in a secure document whose life should be spread over several years.

p0008In addition, a secure document such as a passport implies that the passport pages and therefore the cover carrying the RFID device will be subject to impact blows buffer or affixing of visa exposing the chip to a risk not significant destruction. Disclosure of Invention

p0009Therefore the object of the invention is to remedy these drawbacks by providing a radio frequency identification device support which has good affinity with the bonding of paper and which does not delaminate in thickness and that more protects the RFID destruction risks due to impacts or shocks.

p0010Another object of the invention is to provide an identity booklet such as a passport integrating such a radiofrequency identification device.

p0011The object of the invention is a radio frequency identification device holder comprising a screen-printed antenna on a support and a chip connected to the antenna connecting terminals. According to a main feature of the invention a thermoplastic layer and a top layer of synthetic paper are laminated on the antenna support so as to obtain a water-resistant RFID device and humid environment so that the antenna and the chip are trapped in the thermoplastic and the three layers are inseparable.

p0012Another object of the invention relates to an identity booklet comprising a device holder of radio frequency identification (RFID) according to the first subject of the invention.

p0013Finally, another object of the invention relates to a method of manufacturing a device for radio frequency identification medium (RFID), the device comprising an antenna and a chip connected to the antenna, the method comprising the steps of:

p0014- Screen printing an antenna having connection pads on a support,

p0015- Placing adhesive dielectric material between the antenna connection pads, - Positioning the chip on the way that the chip pads support are opposite the connection pads of the antenna,

p0016- Connecting the chip to the antenna connection pads by exerting pressure on the chip, depositing on the support a thermoplastic layer and an upper layer of a material which does not flow such as a synthetic paper, the layer upper being provided with a cavity at the location of the chip, - laminating together the support, the thermoplastic layer and the upper layer so as to obtain a water-resistant RFID device and the wet and so that the antenna chip are trapped in the thermoplastic and the three layers are inseparable.

p0017Brief Description of Figures

p0018The purposes, objects and characteristics of the invention appear more clearly on reading the following description made with reference to the drawings wherein:

p00191 shows the face of antenna substrate on which is carried the RFID device,

p0020Figure 2 shows in section the antenna carrier on which is carried the RFID device, Figure 3 shows a section of the various layers of the RFID device support,

p0021Figure 4 shows a section of the RFID device support according to the invention,

p0022Figure 5 shows the implementation of the RFID device support on the cover of an identity booklet,

p0023Figure 6 shows a section of the cover of the booklet and the introduction of the RFID device,

p0024Figure 7 shows a section of the RFID device holder according to an embodiment 1 of the invention, 8 shows a section through the cover of the booklet and the establishment RFID device of the support according to the execution variant,

p0025Figure 9 shows the implementation specifications inside pages of the booklet.

p0026Description of the invention

p0027Referring to Figure 1, a first layer 20 serves to support the antenna and having dimensions of those corresponding to a closed passport is to say approximately 88 x 125 mm. The material of the layer 20 is a material which therefore does not flow which does not deform irreversibly when the temperature increases. The material of the layer 20 is preferably a material whose cohesion is very little change during a lamination operation which consists in exerting a hot pressing. The antenna 12 is an essential part of the RFID device consists of one or more turns of conductive ink screen printed polymer loaded with conductive elements such as silver, copper or carbon. Each of the ends of the antenna is connected to one of the two pads 17 and 19 of the connection also screen printed antenna. The turns are interconnected by an electrical bridge 21, more commonly called crossover. An insulating strip 23 of dielectric ink is screen-printed between the cross-over and some of the turns of the antenna 12 to allow the crossing of turns without electrical contact. According to a preferred embodiment of the invention, the antenna is screen printed on the material in several steps. The first step consists in screen printing the antenna coils 12 and the two pads 17 and connections 19 of the antenna. The second step consists in screen printing an insulating strip 23 to allow the crossing of turns of the antenna 12. The third step consists in screen printing the electric bridge 21 for connecting the antenna coil 12 located closest to the outside the group of turns. The next step is to connect the chip to come on the antenna connection pads 12. An adhesive dielectric material is deposited on the antenna support 20 between the two contacts 17 and 19 of the antenna 12. this adhesive material is applied before the chip is placed on the support, unlike the process "Flip chip" in which one adhesive is deposited once the connected chip. This step is much easier to achieve and the yields are much better. The adhesive used is preferably an epoxy resin which crosslinks at 15O⁰C. It is also possible to use a cyanoacrylate adhesive which cures at room temperature.

p0028Once the adhesive material deposited, the chip 10 is positioned on the way of antenna mount that contacts 17 and 19 of the chip are opposite the antenna connection pads as shown in section Figure 2. pressure is then exerted on the chip 10 so that the non-deformable connection pads of the chip s' sink into the bond pads 17 and 19 of the antenna 12. Under the pressure exerted, the the antenna's contacts are then deformed. The antenna support 20 is compressed under the pressure exerted on the chip and may also deform. It is then found that the area of ​​contact between the contacts of the chip and the antenna connection pads 12 is maximum, even when the pressure has ceased to be exercised. The chip connection pads are preferably conical in shape. Under the effect of the pressure exerted, the adhesive dielectric material spreads and covers the entire surface of the chip between the bond pads and penetrates deep into the antenna support. It thus enables the mechanical assembly between the chip 10 and the antenna support 20, and by the same, the electrical contact between the chip and the antenna. The adhesive dielectric material used is preferably fluid and high penetration. The media then undergoes a passage through an oven to cure the adhesive.

p0029Once the chip 10 fixed to the support, the next step consists in laminating together the RFID device and the various layers which form the support of the RFID device. The described embodiment is adapted so that the RFID device support obtained can be integrated into an identity booklet such as a passport.

p0030According to the preferred embodiment of the invention, the various layers of the RFID device holder as shown in Figure 3 are constituted of the antenna support 20, a thermoplastic layer 22 and an upper layer 24 the device is made by laminating the various layers once the chip is fixed on the antenna support 20. a first thermoplastic layer 22 is disposed on the antenna support 20. the thickness of the thermoplastic layer is between 40 and 80 microns and is preferably of the order of 50 microns. The top layer 24 comprises a cavity 26 located so as to be superimposed on the chip and having an area greater than that of the chip so that the pressure exerted during the lamination step is less than the chip since the pressure is exerted uniformly over the entire surface of the sheet but is not exerted at the location of the cavity located above the location of the chip; The cavity 26 is preferably circular with a diameter of about 6 mm. The lamination step consists in welding by hot press molding the layers 20, 22, 24 to obtain a RFID device support 2 as shown in FIG 4. The temperature and the pressure reached is in the order of respectively 160⁰C and 200 bar. As specified above, the antenna support 20 is preferably a material which therefore does not flow which does not deform irreversibly when the temperature increases to 160 ° C. In addition, this material does not delaminate voluntarily or involuntarily with time. The support 20 is preferably a synthetic paper consisting of a single non-oriented layer of a polymer such as polyethylene or polypropylene charged with mineral fillers between 40 and 80%. Its composition gives it a low density of about 0.57 g / cm³ thanks to its microporous network and its thickness is of the order of 180 .mu.m. The thickness could be lower without departing from the scope of the invention. Although the thermoplastic layer 22, in direct contact with the chip, is not pierced by a cavity at the location of the chip, the pressure during lamination is not transmitted to the chip at the point of 'to damage. The temperature and pressure values ​​practiced during the lamination step, the thermoplastic component layer 22 softens and becomes fluid while being imprisoned between the two respective layers of the antenna support 20 and the upper layer 24. During the lamination, the antenna support device gives the compound of the antenna 10 and the chip 12 rigidity and cohesion which prevents electrical breakdown since the material of the antenna support forming the resist layer without deforming and especially without creep at the temperatures and pressure of the lamination step. The thermoplastic layer 22 stiffened imprisoned the reliefs of the antenna support 20 so that the antenna 10 and the chip 12 are embedded in the thermoplastic 22. Indeed, a section of the various layers 20, 22, 24 makes it possible to highlight the fact that the antenna 10 and the chip 12 is molded in the thermoplastic 22, the thermoplastic having covered the chip at the location of the cavity 26. Thus, in a humid environment, it is the thermoplastic layer which gives the RFID device support rigidity and cohesiveness that prevents any electrical breakdown. The thermoplastic can be welded together the two layers 20 and 24 and acts as a glue between these two layers.

p0031The upper layer 24 of a thickness of 180 .mu.m is preferably in the same material as the antenna support 20 thus in the synthetic paper as defined above. The support of the RFID device 2 thus produced by lamination of the layers 20, 22, and 24 shown in section in Figure 3 has a thickness of about 350 .mu.m. The flexibility and versatility of the RFID device 2 obtained carrier are a function of the thickness of the thermoplastic layer 22 used. Plus the thickness of the thermoplastic layer is reduced and the RFID device is flexible and supple. According to FIG 5, the support of the RFID device 2 is adhered to one of the two dishes of the cover 11 of the identification booklet, preferably on the bottom cover 14 but could also be pasted on the top plate 16. The face the RFID device support opposite to the antenna support and chip, so the layer 24 is bonded to the flat cover of the identity booklet in order to protect the chip as possible impacts that might occur in inside the booklet. In general, RFID device support 2 is glued with an adhesive which, once dried is insoluble in 1 water.

p0032To keep the same thickness over the entire cover of the booklet, it is advantageous to affix the other of the front cover of the book, one that does not carry the RFID device support, one or more layers forming a support 3 as shown in Figure 6 and having a total thickness equivalent to the thickness of the RFID device support 2. the support 3 is preferably of identical size to the device holder 2. for example and in accordance with the 6, it is possible to manufacture a support 3 without RFID device consists of a single layer of synthetic paper or 50,^" of laminating together a layer of synthetic paper, a thermoplastic layer and a layer of synthetic paper, the single layer or all layers being of the same total thickness as the assembly of layers 20, 22 and 24. The support 3 thus manufactured is then bonded on the second of the front cover 11 of the booklet, while leaving a free strip of the cover at the location of the hinge of the booklet.

p0033According to an alternative embodiment of the invention, the supports 2 and 3 may be manufactured together so as to be integral to each other by a single synthetic paper upper layer 64 as shown in Figure 7 by a RFID device holder 4. A first thermoplastic layer 22 is disposed on the antenna support 20 whose thickness is between 40 and 80 microns but preferably about 50 .mu.m. A second layer of thermoplastic 62 is also disposed on a second layer 60 of synthetic paper. The layers 20, 22, 60 and 62 having the same size corresponding in length to the size of an identity booklet closed but whose width is slightly less than the width of a closed identity booklet. A top layer 64 is disposed on the layers 22 and 62 so as to leave a space therebetween. The layer 64 comprises a cavity 26 located so as to be superimposed on the chip and having an area greater than that of the chip so that the pressure exerted during the lamination step is less than the chip since the pressure s uniformly exerted on the entire surface of the sheet but is not exerted at the location of the cavity located above the location of the chip; The cavity 26 is preferably circular with a diameter of about 6 mm. The lamination step then consists in welding by hot pressing all the layers 20, 22, 60, 62 and 64. The support 4 by the RFID device a support for the alternative embodiment of the invention is shown in section in Figure 8. the size of the booklet open identity, it has two thick portions 42 and 43, the portion 42 containing the RFID device, the two parts being superposed to dishes 14 and 16 of the cover 11 of the booklet and a thinner portion intended to overlap the hinge identity booklet.

p0034But the RFID device support 2 as described may also be integrated to the booklet by bonding one of its faces, but preferably on the side of the antenna support, on any type of object such as clothing, books, documents paper, packaging, cartons, etc.

p0035The identity booklet 1 shown schematically in Figure 9 is completely formed by the establishment of the inside pages notebook 37. making method is to develop the specifications inside pages using a secure thread to connect them they. In the manufacture of a conventional passport, cover pages are laminated on the cover boards, the flyleaf 36 being laminated to the top plate 16 while the bottom flyleaf 34 is laminated to the lower plate 14. Thus, according the invention, the back of the bottom flyleaf 34 specifications identity booklet of pages is glued and pressed against the RFID device support 2 stuck on the bottom cover 14 of the booklet cover, so the side of the layer of the antenna support 20. Or, as the embodiment described above, the back of the title page below 34 pages of specifications of identity booklet is glued and pressed against the part 42 of the holder 4, the part 42 being 'the one containing the chip and the antenna while the front of the cover sheet 36 is glued and pressed against the portion 43 of the support 4. the glue used is preferably a glue that, once dry becomes insoluble in water. The use of a synthetic paper in making the RFID device support is an indisputable advantage of the invention. On the one hand, the synthetic paper facilitates the lamination operation carried out at temperatures of the order of 160⁰C, since it is stable at these temperatures contrary to thermoplastic materials such as PVC or PETG. The support of the RFID device 2 or 4 made according to the invention of synthetic paper on both sides, facilitating its bonding and optimizes integration into identity booklet as collages are made paper against synthetic paper. Indeed, the synthetic paper has a low density due to its microporous structure, which gives it a good affinity for bonding with the paper in contrast to conventional plastics such as PVC or PET. The identity booklet obtained thus provides the advantage of a greater cohesion between all its parts and in particular between the RFID device support and identity booklet itself. Indeed, the adhesive penetrates deep into the thickness of the synthetic paper as it penetrates the paper and therefore in particular in the paper forming the cover of the booklet, which makes impossible the separation of the layers 20, 22 and 24 therebetween and which makes the three constituent layers of the carrier, inseparable.

p0036The thermoplastic material used for the layers 22 and 52 is preferably polyvinylchloride (PVC), but may also be polyester (PET, PETG), polypropylene (PP), polycarbonate (PC) or of one of acrylonitrile-butadiene styrene (ABS).

p0037Furthermore, tearing volunteer integrated RFID device support booklet is impossible because the synthetic paper does not delaminate in thickness.

p0038During the lamination or later, outside the cover of the booklet can be subjected to a plate with special reliefs to produce a particular grain on the cover and in order to make the tamper-resistant identity booklet. Advantageously, the RFID device of the support and the identity booklet according to the invention may undergo a transition machine washing without the electrical connection between the chip and the antenna being altered thus retaining the ability to be read by electromagnetic coupling with a reader provided for this purpose.

p0039RFID device support and the RFID device can also be made ​​in ISO format of smart cards to be used for card manufacturing contactless smart. The two layers of synthetic paper and the external thermoplastic layer are formed at ISO smart card and the antenna is also adapted so that the size of the turns are slightly less than the ISO format chip cards. In this case, an additional step to the manufacturing process described above consists coming personalize the card by making a print on one of the faces of the card, or both.