Manufacturing process for memory cards comprising graphic elements, and cards obtained by this process.

p0001The present invention relates to cards, including electronic memory cards whose card body consists of graphic elements such as alphanumeric information or drawings for example for decorative or advertising purposes.

p0002When the graphic element has a certain complexity or by the shape of the path or the nature of color shades to get the graphics printing step, by screen printing, offset printing or other methods, can lead to failure especially if it is very demanding on the quality of graphics and colors. If unsuccessful, it must resolve to discard the cards the graphics quality is deemed insufficient. This means that the costs in material, components and machining steps for manufacturing the card before the graphics of the manufacturing step are lost. These costs are particularly high if the realization of graphics occurs when electronic module has already been implanted in the body of the card. This occurs particularly but not exclusively, when the card is manufactured by molding the body of the card directly on the electronic module according to the technique described in the French patent application nr 87/00446.

p0003According to this technique an electronic module is placed in a mold whose imprint defines the outer shape to be given to the card coprs. After demoulding a memory card is obtained having a card body with its final shape and wherein the electronic module is already implanted. If, during the subsequent step of producing graphics, the result is unacceptable, we understand that this is the full cost of production of the card is lost.

p0004It was also proposed to make the card body by injection molding of a plastic material. This technique is described in the patent application 267 826. To reduce the cost of production is preferably used as an injection material acrylourethane butadière styrene (ABS). This material has the disadvantage of evil is to construe the realization of graphics on the card body surfaces by standard printing techniques: screen printing or offset.

p0005To overcome these disadvantages an object of the invention is to provide a card making method, in particular smart card, wherein the graphics of the manufacturing step of the card bodies can in itself cause the rejection of the card or which accomplishes the graphics independently of the nature of the material used to make the body of the card.

p0006To achieve this object, the method for producing a card comprising a card body having two main faces and at least one graphical element is characterized in that it comprises the following steps:<ul><li>a) furnishing a mold whose imprint defines the outer shape of the card body,</li><li>b) in the mold has at least one support element comprising a graphic element, in place maintaining said support member so that it remains substantially parallel to the mold faces defining the footprint of the main faces of the card body, Injecting into said mold a plastic material such that the plastic material occupies all of the espage limited by said imprint not occupied by said mold support member and the piece thus produced is unmolded.</li></ul>

p0007In a first mode of implementation the graphic element of the support element includes printing elements and, during injection of the plastic material in the mold said printing elements adhere to the face of the volume of plastic material injected into contact with said support member, and upon demolding separating the support member from the molded part, whereby said printing elements remain on said face of said body.

p0008Preferably during step b there is further placed in said mold an electronic module having an access face and said electronics module is maintained so that its access face is pressed against one of the main faces of the cavity, and during step c the plastic material fills the entirety of the space limited by said imprint not occupied by said support element and said electronic module mold.

p0009According to a variant of the first embodiment of the graphic element of said support member comprises a first and a second printing element disposed on either side of a separating layer and the opaque injection plastics material is transparent. So visually, it is as if an impression was made on each of the two main faces of the card body.

p0010According to a second embodiment said support member is made of a non-transparent material provided on at least one of its faces a graphic element and in that said injection plastics material is transparent.

p0011Other features and advantages of the invention appear more clearly on reading the following description of several embodiments of the invention given as non-limiting examples. The description refers to the accompanying drawings in which:<ul><li>Figure 1 is a vertical sectional view of a support element provided with graphic elements according to a first embodiment of the invention;</li><li>Figure 2a is a vertical sectional view of a mold for producing a smart card body using a support element according to Figure 1;</li><li>Figure 2b is a similar view to that of Figure 2a showing the inside of the mold after injection of the plastic material.</li><li>Figure 3 shows in vertical section a mold usable variant in a variant of the first embodiment of the invention;</li><li>Figure 4 shows an alternative support member usable with the mold of Figure 3;</li><li>Figure 5 shows in partial vertical section a card body obtained by the implementation of the method according to Figs 3 and 4.</li><li>Figure 6 shows in vertical section a mold for the implementation of a second variant of the first embodiment of the invention.</li><li>Figures 7a and 7b show respectively a vertical section and top view of a mold for the implementation of a second embodiment of the invention.</li><li>Figure 8 shows in vertical section a mold for the implementation of a variant of the second embodiment of the invention.</li><li>Figure 9 shows in vertical section a support member provided with electronic modules;</li><li>10 shows, in vertical section, a mold for use the support element of Figure 9 according to a third embodiment of the invention;</li><li>11 shows, in top view, an electronic memory card obtained according to the third embodiment of the invention;</li><li>Figure 12 shows, in vertical section, several support elements for producing a card according to a variant of the third embodiment of the invention; and</li><li>13 shows, in vertical section, a mold for use in the variant of the third embodiment of the invention.</li></ul>

p0012Before explaining in detail all of the invention will be described with reference to Figure 1, a usable print media element.

p0013The support member, bearing the reference 10 comprises a carrier 12, or backing sheet, plastic material. The support 12 is preferably made of polyester and has a thickness of about 25 micrometers.

p0014On this support 12 which acts as a mechanical support are made later for printing elements to achieve the desired graphics. For each printing element there is a release layer 14; a decorative layer 16 consisting of pigments; possibly a layer of varnish 18; and an adhesive layer 20 whose thickness is of the order of 1 to 2 micrometers.

p0015On one sheet support 12 can carry a large number of identical patterns. Such a product is available from the German company Leonard Kurz GmbH.

p0016In the following step is carried out the card body by injection molding of a plastic material which is preferably of ABS. 2a and 2b show the mold used. It comprises a fixed part 50 and a movable portion 52. These two portions define a cavity 53 that gives the outer shape of the card body. The fixed portion 50 defines by its inner wall 54 a of the main faces of the card body. In the wall 54 there is arranged a ring 55 which protrudes into the cavity 53. The core 55 is used to set in the card body a cavity in which is subsequently set the electronic module. The movable portion 52 defines by its inner wall 56 of the second main face of the card body and by its inner wall 58 most of the portion of the card body. The fixed 50 and movable portions 52 each have a bearing surface 60 and 62, these two bearing surfaces normally being in mutual contact when the mold is closed. Finally the movable part 52 has an injection nozzle 61 opening into the face 56 and disposed facing the core 55.

p0017The mold being open, the band formed by the support 12 is placed between the fixed part 50 and movable part 52 of the mold. The band is placed relative to the footprint 53 so that the graphics 16 carried by the support 12, be perfectly positioned with respect to the side wall 58 of the print, that is to say with respect to the slice of the card body which will be realized. More graphic elements 16 are turned towards the face 56 of the cavity 53. The mold is then closed. The support 12 is clamped between the bearings 58 and 60 of the two mold parts in the region of the support 12 which surrounds a pattern. Then proceeds to the injection of plastic material into the cavity 53 by the injection nozzle 61. The ABS is preferably injected at a temperature between 220 ° C and 280 ° C .. The plastics material fills the footprint 53 by plating the support 12 against the inner wall of the mold 54 and the core 55 as shown in Figure 2b. . The plastic material completely fills the cavity 53 and is in contact with the graphic 16. Under the effect of pressure and temperature, decorative elements 16 are fixed on the corresponding face of the volume of plastic material 62 tending to separating from the support 12. This is achieved by activation of the adhesive layer 20 and release layer 14.

p0018After opening the mold the card body is demoulded having the desired graphics 16 on its main face and the card body so obtained is separated from the support 12.

p0019It goes without saying that the card body to have a thickness of 0.8 mm, the thickness of the mold cavity (distance between faces 54 and 56) should be slightly greater than this value to account for the thickness of the backsheet 12.

p0020Figure 3 shows a mold for a second implementation mode of the invention. The mold comprises, like that of Figures 2, a fixed part 50 and a movable part 52. These two parts define an internal cavity 53 which has substantially the shape that is to be given to the card body. The fixed part 50 defines the main face 54 and the side face 58 of the cavity 53. A core 55 'projects into the major face 54 to define the shape of the cavity to be made in the card body. An injection nozzle 61 'is disposed in the core 55'. The movable portion 52 defines the second main face 56 of the cavity 53. The portions 50 and 52 have two contact surfaces 60 'and 62' which are in contact when the mold is closed. The scope 62 is substantially in the plane of the main face 56.

p0021For the implementation of the invention according to Figure 3 is used a support member 10 'shown in Figure 4. It is identical to the support member 10 of Figure 1 except for the decorative layer. The decorative layer 16 'is constituted by two sub decorative layer 15' and 17 'between which is interposed an opaque layer 19' of separation. And the decorative layer 16 'includes two different graphics that are arranged on both sides of an opaque layer separation.

p0022The implementation of the second embodiment of the invention method is as follows: The support element 10 is placed in the mold of Figure 3 between the fixed 50 and movable parts 52. Then the mold is closed and the periphery of backsheet 12 initiating the decorative element 16 '. the decorative element 16 'faces the main face 54 of the cavity 53. By the nozzle 61', injecting a transparent or translucent plastic material. This is for example a polycarbonate or a transparent ABS. When filling the cavity 53 of the mold, the decorative layer 16 'is detached from the backsheet 12 and adheres to the main face of the volume occupied by the plastic material. During mold release and extraction of the resulting card body backsheet 12 remains in the mold.

p00235 shows the card body thus obtained. The card body 80, with its cavity 82 which opens into its main face 84, is completely transparent. The rear main face 86 is formed by the decorative layer 16 '. If we look at the card body 80 by its front face 84 can be seen through the transparent material, the graphics formed by the decorative sublayer 15 '. On the contrary, if the card body by looking at the posterior surface 86 is directly sees the graphics defined by the decorative sublayer 17 '. Given the reduced thickness of the card body, 0.8 mm, the optical effect due to the transparent material layer is negligible.

p00246 shows a mold variant operable to produce an electronic memory card having graphical elements on its two main faces. The mold is formed in three parts. A first part 90, mobile, comprises the portion 92 of the mold cavity that defines the first main face of the card body, including the core 93 for defining the cavity in the card body.

p0025A second part 94, movable part 96 includes the imprint of the mold which defines the second main face of the card body. A third portion 98, fixed, which is sandwiched between the portions 90 and 94 of the mold when the latter is closed, comprises the portion 100 of the cavity that defines the edge or the edge of the card body. The portion 98 of the mold has, for example, two injection nozzles 102 and 104.

p0026The manufacture of a card using the mold of FIG 6 is performed as follows: the mold is opened, that is to say, the portions 90 and 94 are spaced from the fixed part 98. A first film 12a printing element support is placed between the portions 90 and 98 of the mold as has already been described in connection with Figure 3. the support element 12<u>at</u> 12c has an opening for the core of the passage 93.

p0027A second film carrier 12b of print elements is placed in the same manner between the parts 98 and 94 of the mold. Then the mold is closed with the aid of not shown locking means in Figure 6. Thus, the carrier film 12a and 12b are secured to the mold because they are pinched between the three parts 90, 94 and 98 of the mold. This is followed by the injection of plastic material into the mold through the nozzles 102 and 104, and demoulding the resulting map, the film support 12a and 12b remaining in the mold, only the graphic elements formed by the decorative layers remaining attached on the main faces of the card body.

p0028In the various variants of the first embodiment described above the graphic on the card body is obtained by transferring, during molding, a decorative layer from the support sheet of the print media element on the plastic material forming the card body.

p0029It is also possible according to a second embodiment of the invention to provide graphics using a printing medium element which forms a "tag". In other words it is the assembly formed by the support sheet and the decorative layer which adheres the plastic material during injection of the material into the mold.

p0030Figures 7a and 7b illustrate the second embodiment of the graphics on the map.

p0031The support element is formed by a portion (110) of a sheet of plastic material which has the general shape of the main faces of the card body, that is to say a rectangular shape. the support member further comprises four extensions each starting from a peak of the actual support member. Only the extensions 112 and 114 are visible in Figure 7a. The support member 110 is for example cut from a sheet of polycarbonate whose thickness is of the order of 0.1 mm. Of the two remaining faces 110a and 110b of the support member or on one of these means is carried by all the desired graphics, represented by 122 and 124 in Figure 7a. Naturally on the same polycarbonate sheet simultaneously realizes the impressions corresponding to a large number of support elements and the supporting elements 10 are then individualized by cutting in order to obtain the shape shown in FIGS.

p0032Figures 7a and 7b show a form usable mold for producing an electronic smart card body from the support member 110. The mold 140 comprises two parts 142 and 144 which define a recess or cavity 146 having the external shape of the body of the card to be produced. The portion 42 of the mold further comprises recesses 148-154 corresponding to the extensions of the support member 110. The main face 142<u>at</u> of the cavity 146 includes a core 156 which projects into the cavity 146 to define a recess in the card body for fixing the electronic module. The mold 140 also comprises two injection conduits 158 and 160 belonging respectively to the parts 142 and 144 of the mold and opening into a "wedge" of the internal cavity 146 of the mold.

p0033The manufacture of the card is performed as follows. the support member 110 is placed in the portion 142 of the mold 140. More specifically, the extensions of the support member are disposed in the cavities 148 to 154. Then the portion 144 of the mold is fixed to the portion 142.

p0034the support member 110 is thus positioned and secured to the mold by extensions such as 112 and 114. The member 110 separates the cavity 146 into two half-cavities. This is followed by the injection channels 158 and 160, to the injection of the plastic material used for making the card body in the cavity 146 on either side of the element 110. The injection plastic material is a transparent material capable of adhering to the material forming the support member 110 is preferably chosen also a polycarbonate. During injection the plastic material fills the portion of the cavity 146 not occupied by the support member 110, thereby defining the card body. then demoulding the piece thus produced by separating the portion 144 of the part 142 of the mold. then cut the "corners" of the card body to give them rounded and suitable to remove the extensions 112 and 114 as well as the "carrot" of injection. After the cutting operation a card body is obtained a transparent material which is embedded in the support member. The fact that the plastic material of the body is transparent graphics, drawings or alphanumeric indications are visible as in a map by a known method. Furthermore, the design is protected by the transparent plastic.

p0035Instead of polycarbonate, one may use other transparent moldable plastic materials such as polysulphones or transparent moldable transparent polyesters. We could also use a crystal or styrene-acrylonitrile-nitryl polystyrene.

p0036According to a first variant of this second embodiment of the invention the support element 110 has greater dimensions than those of the main faces of the card body, and the extensions are removed. The support element is introduced into the mold. When closing the latter the periphery of the support member is clamped between the parts 142 and 144 of the mold. After demoulding, it is necessary to cut the periphery of the support member which extends beyond the card body.

p00378 shows another embodiment of a mold 210 for a second variant of the second implementation of the method according to the invention. According to this variant the front graphic elements 212 and 214 provided with their rear graphics 212 'and 214' are similar to the support member 110 of Figure 7 but they have larger dimensions than those of the main faces of the card body. The mold 210 consists of three parts: a front portion 216 which defines the main face 216<u>at</u> the card body; a rear portion 218 which defines the main face 218 back<u>at</u> the card body; and an intermediate portion 220 that defines the side wall 220<u>at</u> the card body and the thickness of the card. Parts 216 and 218 of the mold of preference you have depression systems such as 224 to better keep up the support elements. In addition, the portion 216 comprises a core 222 to define the cavity to be made in the card body.

p0038To make the card the procedure is as follows. The mold being open, is placed the support member 212 against the face 216<u>at</u> the mold. The support member 212 includes an opening 213 to the core 222. Then the passage is placed the spacer 220, the periphery of the support member 212 is pinched between the mold parts 212 and 220. Then is placed the support member 214 and makes active systems to depression 224. Finally is put in place the portion 218 of the mold, the periphery of the support member 214 being clamped between the spacer and the portion 118 of the mold. One then proceeds to the injection of plastic material into the mold through the injection channel 226.

p0039In the above description in connection with Figures 7 and 8, it was considered that the support elements with their graphics were cut before their introduction into the mold. However, it goes without saying that, in cases where the support member is held in place in the mold by gripping its periphery between two parts of the mold, the support elements can be left in strip. The web is moved one step before each molding operation of a card at each molding operation a support member (or two support elements in the case of Figure 8) is depicted in conjunction with the footprint of mold, the latter of course being open.

p0040By the various implementations of the method described above one obtains a card body having a graphic on one or both main faces and provided with a cavity for receiving the electronic module. The electronic module is then fixed in the cavity by various techniques including those described in European patent applications 197 847 and 254 640.

p0041According to a third embodiment of the invention it is possible to obtain the map with the electronic module and its graphics made on one or both faces of the card body. This third embodiment of cards is to play in the support sheet of the support element a dual role on the one hand it supports the decorative layers to achieve the graphics: the other, it serves as a temporary support and means positioning of the electronic module into the injection mold. And the electronic module is embedded, except for its access face, in the plastic material forming the card body.

p0042This technique can be applied to all the embodiments described above. We will therefore describe two examples of implementation of the third embodiment of the invention.

p0043Referring now to Figures 9 to 11 will be described a first embodiment of electronic memory cards according to the invention.

p0044One starts with a support member 10 which includes a plurality of identical patterns, each pattern corresponding to the entire graphics to be formed on one of the body of the card faces. Figure 10 A units are shown and B. Each pattern is separated from the neighboring patterns with a blank whose usefulness is explained below.

p004511 shows a 330 card body produced according to the invention. In the visible main face of the card body the electronic module 332 is shown which only the external electrical contact tabs 334 are visible. Also shown in the areas 336 of the card body which comprise a graphic. The area 336 leaves free the portion of the face of the card body 330 occupied by the external tabs 334 of electrical contact.

p0046Returning to Figure 9, we see that for each pattern, the area where the graphics are made 336 leaves exposed part 338 of the plastic support 12 which must be the electronic module 332 when the card is complete .

p0047The electronics module 332 comprises a lead frame or a printed-circuit element on which are formed the external tabs 334, a semi conductor chip 340 attached to the circuit board or the lead frame, the son conductors 342 which connect the terminals of the chip 340 to the contact pads 334 and a potting material 344 that surrounds the chip 340 and the son 342. a module 332 is adhered to the support 12 at each location 338, such that each pattern comprises a module.

p0048As shown in FIG 9, the external face of the external contact pads is directly bonded to the support 12.

p0049This produces a strip formed by the support 12 which has on one of its faces a plurality of patterns (A, B ..) each unit comprising an electronic module 332.

p0050In the following step is carried out the card body by injection molding of a plastic material which is preferably of ABS. Figure 10 shows the mold used. It comprises a fixed part 350 and a movable portion 352. These two portions define a cavity 353 that gives the outer shape of the card body. The fixed portion 350 defined by the inner wall 354 a of the main faces of the card body. The movable portion 352 defined by the inner wall 356 the second main face of the card body and the inner wall 358 portion of the card body. The fixed parts 350 and 352 each comprise a movable range 360 ​​and 362, these two bearing surfaces normally being in mutual contact when the mold is closed.

p0051The mold being open, the band formed by the support 12 is placed between the fixed part 350 and movable part 352 of the mold. The tape is positioned relative to the footprint 353 such that the graphics 16 carried by the support 12 and, consequently, the electronic module 332 are perfectly positioned relative to the side wall 358 of the cavity, that is to say with respect to the portion of the card body which will be realized. Then the mold is closed. The support 12 is clamped between the bearing surfaces 358 and 360 of the two mold parts in the area D of the support 12 which surrounds a pattern. Then proceeds to the injection of plastic material into the cavity 353 through the injection nozzle 364, the ABS is preferably injected at a temperature between 220 ° C and 280 ° C .. Preferably the nozzle 364 is disposed at the center of the wall 56 of the movable part 352. the plastic material fills the cavity 353 by plating the support 12 against the inner wall 354 of the mold. The plastic material surrounding the electronic module 332, except for its face bonded to the support 12 and is in contact with the graphic 336. Under the effect of pressure and temperature, the decorative elements 336 are fixed on the corresponding face of the volume of plastic material tends to separate from the support 12. This is achieved by activation of the adhesive layer 20 and e the release layer 14.

p0052If the electronic module 332 has a sufficiently reduced thickness relative to the thickness of the card, it is possible to provide that the injection nozzle opens into the face 364 of the mold 356, opposite the electronic module. One can also provide a plurality of injection nozzles. Also it is possible to dispose of the injection nozzles in the side face 358 of the mold cavity. Of preference you then the nozzles are arranged in some "corners" of the mold cavity.

p0053After opening the mold card body is unmolded inserré in which the electronic module 332 and has the desired graphics 336 on its main face.

p0054It is understood that the support 12 has a dual role, it allows the realization of graphics, and it ensures the precise positioning of the electronic module in relation to the mold cavity and thus relative to the card body. In addition the module's external pads being bonded to the support 12, they are protected against a possible rise of the injection material that might tend to cover them.

p0055The support 12 that bears more or electronic module or graphics remain in the mold after removal of the card.

p0056Referring now to Figures 12 and 13 will be described a second example of the third embodiment of the invention. According to this second embodiment, two bearing elements corresponding to each of the main faces of the card body are established prior to injection of plastic material.

p0057Figure 12 shows the front support member 470 and the rear support member 472. The front support member 470 simultaneously forms the insulating support of the electronic module. The front element 470 comprises a rectangular sheet 474, such as ABS which has the shape of the main faces of the card to be produced. In the appropriate area, the sheet 474 has on its outer face 474<u>at</u> metallizations 476 which form external electrical contact tabs of the card. A semiconductor chip 478 is fixed on the inner face 474b of the support 474 and connections 480 provide the electrical connection between the terminals of the semiconductor chip 478 and external tabs 476. The wafer 478 and the connections 480 are preferably embedded in an insulating material 482.

p0058Prior to securing the chip 478, the printed graphics 483 are formed on the outer face 474<u>at</u> of the sheet 474 in the unoccupied part of the metallization 476.

p0059The rear support member 472 is also constituted by a sheet portion 484 a plastic material which has the dimensions of the rear main face of the card body. On the outer face 484<u>at</u> of the sheet 484 are made 486 prints required.

p006013 shows in vertical section a mold 490 used for producing a card according to the second embodiment of the invention. The mold 490 comprises a first portion 492 that defines a cavity 494 having the external shape of the card body to be produced. 492 of the mold part comprises a plurality of vacuum systems 500 opening into the main face 492a of the cavity 494. It also comprises an injection channel 496 opening into a "wedge" of the cavity 494. The second part 498 of the mold 490 defines the second main face 498<u>at</u> the card body. A plurality of vacuum systems 500 open into the face 498<u>at</u> Part 498 of the mold.

p0061Manufacturing a memory card according to this second embodiment is obtained in the following manner: putting in place against the face 492<u>at</u> Part 492 of the mold the front support member 470 which also includes the electronic module. It makes active vacuum system which keeps close element 470 against the face 492a. In the same manner is placed the rear support member 472 against the face 498<u>at</u> the part 498 of the mold 490 and it makes the active vacuum systems 500 to maintain the support member 472 against the face 498<u>at</u>. It then closes the mold in the fixing portion 498 of the part 492. In the injection channel 496 is made to penetrate a suitable plastic material which fills the cavity 494 and adhered to the inner faces of the support members 470 and 472. Preferably the material injection is the same as that which constitutes the support members 470 and 472.

p0062then opening the mold 490 and is extracted from the resulting part. a memory card is thus produced which has on its two main faces graphics, graphic elements that have been made on the support members prior to the actual achievement of the card.