Abstract:
The invention relates to a customized multi-layer support which takes the general form of a card, such as an identification card. The support includes a card body, the upper face of which is provided with externally-visible personal information; and a film which is at least partially transparent and which is fixed to the upper face of the card body. The support has boundary lines which define the areas of the aforementioned film with reduced or increased mechanical strength. The invention also relates to a method of producing one such customized support.

Description:
This disclosure is based upon French Application No. 02/10281, filed Aug. 13, 2002, and International Application No. PCT/FR2003/002532, filed Aug. 13, 2003, the contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to a personalized multilayer support in the general shape of a card. 
     The present invention relates in particular to cards of the laminated type, that is to say to cards which comprise several layers of plastic which are superposed on one another and bonded to one another by hot lamination. 
     In general, a personalized multilayer support in the general shape of a card, such as an identification card, comprises:
         a card body which is provided on an upper face with personal information which is visible from outside,   an at least partially transparent film which is fixed to the upper face of the card body.       

     In most laminated cards which comprise information printed on one face, for example bank cards and identity cards, the adhesion between the card body and the transparent film is obtained by using an adhesive coating. 
     A protective layer is often bonded to the upper face of the transparent film, by means of an adhesive coating, with a view to protecting the color photograph or the personal information written on the plastic card. 
     Using special means, it is possible to separate (“delaminate”) two layers of the card, which makes it possible for criminals to modify the personal information and then to bond the two layers to one another once again. 
     At present, in the field of identity cards, it is acknowledged that this possibility of separating two layers of the card represents a significant weakness of plastic cards in terms of guaranteeing the authenticity of the information contained thereon. 
     SUMMARY OF THE INVENTION 
     The invention aims in particular to overcome these drawbacks. 
     To this end, the invention proposes a personalized multilayer support in the general shape of a card, such as an identification card, comprising:
         a card body which is provided on an upper face with personal information which is visible from outside,   an at least partially transparent film which is fixed to the upper face of the card body,   marker lines which delimit zones of the film having reduced or increased mechanical strength, forming tear scores so that the film is torn if an attempt is made to peel off the film,   characterized in that the marker lines depict at least one identification motif which is visible from outside.       

     According to other features of the invention:
         the marker lines comprise weld beads formed at the interface between the film and the card body;   the marker lines comprise grooves formed in at least one of the faces of the film;   the grooves pass through the entire thickness of the film;   the upper face of the transparent film is covered with a transparent protective layer;   the upper face of the transparent film comprises personal information;   the transparent film is fixed to the upper face of the card body by bonding by means of an adhesive coating.       

     The invention also proposes a method of manufacturing a personalized multilayer support in the general shape of a card, such as an identification card, of the type comprising:
         an “assembly” step, during which an at least partially transparent film is fixed to the upper face of a card body,   a “personalization” step, during which personal information is placed on the upper face of the card body so that the personal information is visible from outside through the transparent film,   characterized in that, after the assembly step, a “security” step is carried out, during which marker lines are produced by means of a laser beam so as to delimit zones of the film having reduced or increased mechanical strength, forming tear scores with a view to causing the film to be torn if an attempt is made to peel off the film.       

     According to other features of the method according to the invention:
         the marker lines are produced by forming grooves on at least one face of the transparent film;   the marker lines are produced by forming weld beads at the interface between the transparent film and the card body;   the marker lines are produced by forming grooves on at least one face of the transparent film and marks and/or welds at the interface between the transparent film and the adjacent card body, in line with the grooves.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the invention will emerge from reading the following detailed description which will be better understood with reference to the appended drawings, in which: 
         FIG. 1  is a view in section which schematically shows a personalized multilayer card produced in accordance with the teaching of the invention; 
         FIG. 2  is a view from above which schematically shows the personal information and identification information borne by the card of  FIG. 1 ; 
         FIGS. 3A ,  3 B,  3 C and  3 D are views similar to that of  FIG. 1  which show a method in accordance with the teaching of the invention for manufacturing the card of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1 and 2  show a personalized multilayer support  10  which is produced in accordance with the teaching of the invention. 
     The personalized multilayer support  10  is in this case an identification card, for example a national identity card. 
     The card  10  comprises a card body  12  which is made of an opaque plastic material and which bears, on its upper face  14 , personal information  16  of the card  10 . 
     The personal information  16  comprises for example a photograph  18  of a person and alphanumeric characters  20  relating to the identity of the person, as shown in  FIG. 2 . 
     A transparent film  22  is bonded to the upper face  14  of the card body  12 . 
     The film  22  may be partially transparent, that is to say it may be transparent only above the personal information  16 , which must be visible from outside. 
     According to the embodiment shown here, the film  22  bears, on its upper face  24 , personal information  26  which is redundant with respect to the personal information  16  borne by the card body  12 . 
     In  FIG. 2 , the personal information  16  borne by the card body  12  is shown in fine lines and the personal information  26  borne by the film  22  is shown in bold lines. 
     Advantageously, a transparent film  28  which forms a protective layer is bonded to the upper face  24  of the film  22  and covers the latter. 
     In accordance with the teaching of the invention, the card  10  comprises marker lines  30 ,  32  which delimit zones of the film  22  having reduced or increased mechanical strength. 
     The marker lines in this case comprise weld beads  30  and grooves  32 , which have been shown schematically in  FIG. 1 . 
     In order to simplify the drawing, a single weld bead  30  and a single groove  32  have been shown in  FIG. 1 . 
     The weld beads  30  are formed at the interface between the film  22  and the card body  12  so that they create zones in which the mechanical strength of the film  22  with respect to being peeled off is higher than in zones of the film  22  which are simply bonded to the card body  12 . 
     Thus, if an attempt is made to peel off the film  22  from the card body  12 , the portions of the film  22  which do not comprise a weld bead  30  will be peeled off more easily than the portions of the film  22  which comprise weld beads  30 , which latter portions will remain secured to the card body  12  and will cause the film  22  to tear at the join between the two type of portions, thereby causing the film  22  to rip. 
     The grooves  32  in this case pass through the entire thickness of the film  22 , thereby forming cuts in the film  22  so that the join between the portions of the film  22  which are adjacent to these grooves  32  is weakened and therefore has very little mechanical strength. 
     Thus, if an attempt is made to peel off the film  22  from the card body  12 , the portions adjacent to the grooves  32  will separate, thereby causing the film  22  to rip. 
     Ripping of the film  22  prevents it from being reused, and the portions of film  22  which remain fixed to the card body  12  by the weld beads  30  will impair the surface finish of the card body  12 . 
     Consequently, any attempt to falsify the card  10  will be noticeable in the form of visible defects in the layers  12 ,  22 ,  28  of the card  10 . 
     It will be noted that the zones of reduced or increased mechanical strength in the film  22  form tear scores so that, if an attempt is made to peel off the film  22 , the latter will tend to rip at the point of separation between the zones of high mechanical strength and the zones of lower mechanical strength. 
     According to one variant embodiment (not shown) of the invention, the grooves  32  may be formed on one of the faces of the film  22  without passing through the entire thickness of the film  22 . Such a type of groove  32  then forms tear scores which are designed to tear if an attempt is made to peel off the film  22 . 
     Advantageously, as shown in  FIG. 2 , the weld beads  30  and the grooves  32  may be produced in the form of lines which are fine enough to make it possible to depict motifs  34 ,  36  which are visible from outside through the film  22  and the film  28 . 
     According to the embodiment shown here, the weld beads  30  and the grooves  32  depict a main identification motif  34  which may represent for example a logo or a stamp, with a view to facilitating visual identification of the card  10 . 
     The weld beads  30  and the grooves  32  in this case depict a secondary motif  36  which represents wavy lines passing over the entire surface of the card  10 . This secondary motif  36  facilitates the detection of visible defects on the card  10 . 
     Advantageously, the marker lines  30 ,  32  may be arranged in sensitive zones of the card  10 , that is to say the zones which are most likely to be peeled off, for example around the photograph  18  or close to the edges of the card  10 . 
     Of course, the marker lines  30 ,  32  may be discontinuous and they may be formed by a series of dots. 
     According to one variant embodiment (not shown), the marker lines  30 ,  32  may consist solely of weld beads  30  or solely of grooves  32 . 
     With reference to  FIGS. 3A to 3D , a description will now be given of a method of manufacturing the card  10  in accordance with the teaching of the invention. 
     During a first “assembly” step, which is shown in  FIGS. 3A and 3B , the two first layers  12 ,  22  forming the card  10  are fixed together, in this case by bonding. 
     To this end, according to the embodiment shown in  FIG. 3A , a first layer  38  of an adhesive coating is applied to the lower face  15  of the transparent film  22 . 
     The card body  12  and the film  22  are then superposed in the direction of their thickness, and then these two layers  12 ,  22  are hot-laminated. This ends the assembly step. 
     Of course, the fixing of the film  22  to the card body  12  may be carried out by other means, for example by cold fixing means, by crosslinking, etc. 
     During a second “personalization” step, which is shown in  FIG. 3B , the personal information  16 ,  26  is provided on the card  10 . 
     According to the embodiment shown here, the personal information  26  is printed on the upper face  24  of the transparent film  22 , for example by thermal transfer, or by any other suitable printing means. 
     The personal information  16  is provided on the upper face  14  of the card body  12  by means of a laser beam  42 . 
     During a third “security” step, the marker lines, in this case weld beads  30  and grooves  32 , are formed by means of a laser beam  42  which passes through the transparent film  22 . 
     The weld beads  30  and the grooves  32  are obtained by selecting a given power of the laser beam  42  and optionally by selecting a given focal point of the laser beam  42  in the thickness of the film  22 . 
     The choice of frequency of the laser pulses, the speed of travel of the laser beam  42  and the choice of material forming the transparent film  22  also have an influence on the technical effect obtained by the laser beam  42 . 
     Since the card body  12  is opaque, the laser beam  42  can pass through the transparent layer  22  but is stopped at the interface between the card body  12  and the film  22 . 
     It will be noted that the carrying out of the security step by means of a laser beam  42  makes it possible to form grooves  32  of varying shape, for example of the same shape as the personal data  16  or  26 . 
     Advantageously, the laser beam  42  used to form the marker lines  30 ,  32  is of the same type as that used to personalize the card  10 . 
     During a fourth “protection” step, which is shown in  FIG. 3D , the transparent protective film  28  is fixed to the upper face  24  of the transparent film  22 , for example by bonding. 
     According to one variant embodiment (not shown) of the method according to the invention, the security step may be carried out after the protection step. In this case, the grooves  32  formed by means of the laser  42  pass through the transparent film  28  and the film  22 . 
     This variant embodiment has the advantage of allowing all the layers  12 ,  22 ,  28  of the card  10  to be made secure at the same time, including the making secure of a paper layer if there is one. 
     It will be noted that the security step may be carried out before or after the personalization step. It may also be carried out between providing the personal information  26  and providing the personal information  16 . 
     Of course, the grooves  32  which form tear scores in the film  22  may also be produced using mechanical means. However, in the application of the invention to laminated multilayer cards  10  it is preferable, in particular for reasons of cost and manufacturing simplicity, to use the local application of heat after the assembly step. 
     The method according to the invention makes it possible to make the card  10  secure in an economical manner, with high positioning accuracy of the marker lines  30 ,  32 . 
     According to one variant embodiment (not shown) of the method according to the invention, the local application of heat which makes it possible to form the weld beads  30  may be carried out by hot-marking using heat masks. 
     The design of the mask is determined by the position of the sensitive zones of the card  10 , for example of the photograph. 
     The mask is applied to the card  10  by a machine such as a hot press for applying holograms and producing signature plates. 
     The mask heats the plastic layers  12 ,  22 ,  28  until the plastic melts so as to weld the various layers  12 ,  22 ,  28  to one another. 
     The heating of the plastic may be obtained by preheating the mask, for example using an electrical system, or directly by high frequencies or microwaves. 
     The invention also aims to provide a personalized support in which the marker lines are produced in such a way that they correspond to cutting of the film located on the surface of the card with marking and/or burning of the adjacent lower surface along and in line with these lines. The marking and/or burning may also be accompanied by a welding of the edges of the groove resulting from the cutting to the adjacent surface. These operations are carried out by a single pass or possibly two passes of a laser beam. The invention is notable in particular in that, in line with and along the grooves resulting from the cutting lines, marks and/or welds are found on the lower surface in contact with the film.