SYRJANEN, Taru (Intellectual Property Dpt6 Rue de la Verrerie, Meudon, F-92190, FR)
| CLAIMS: 1. A security document (1 ), comprising: at least a first layer (10), a second layer (11) and a third layer (14) attached to each other, at least one of said layers comprising a hole (15) through it, and an electronic module (4) arranged in said hole (15), characterized in that a first separation layer (12) slightly bigger than the hole (15) is arranged between two of said layers (10, 11, 14) at the location of said hole (15) with the electronic module (4) to prevent attachment of said two layers at least above or below the electronic module (4). 2. A security document according to claim 1, characterized in that said first separation layer (12) is located above said electronic module (4), and a second separation layer (13) slightly bigger than the hole (15) is arranged between two layers (10, 11, 14) at the location of said hole (15) with said electronic module to prevent attachment of said layers below said electronic module (4). 3. A security document according to claim 1 or 2, characterized in that at least said first or second separation layer (12, 13) is a layer of a printable ink. 4. A security document according to one of claims 1 or 3, characterized in that said first, second and third layer (10, 11, 14) are made of polycarbonate. 5. A method of manufacturing a security document (1), comprising at least: providing a first layer (10), a second layer (11) and a third layer (14), one of said layers (10, 11, 14) having a hole (15) through it, arranging an electronic module (4) in said hole (15), attaching said first layer (11), said second layer (12) and said third layer (14) to each other, characterized in that prior to attaching said layers (10, 11, 14) to each other said method comprises: providing a first separation layer (12), slightly bigger than the hole (15), between two of said layers (10, 11, 14) at the location of said hole (15) with the electronic module (4) to prevent said two layers from attaching to each other at least above or below the electronic module (4). 6. A method according to claim 5, characterized in that said first separation layer (12) is arranged above the electronic module (4) to prevent attachment of layers above said electronic module (4), and a second separation layer (13), slightly bigger than the hole (15), is arranged between the two layers (11, 12, 14) at the location of said hole (15) with the electronic module (4) to prevent attachment of layers below said electronic module (4). 7. The method according to claim 5 or 6, characterized in that at least one of said first and second separation layers (12, 13) is provided by printing. 8. The method according to one of claims 5 to 7, characterized in that said first, second and third layer (10, 11, 14) are made of polycarbonate. 9. The method according to one of claims 5 to 8, characterized in that at least one of said first and second separation layers (12, 13) is provided as a layer of printable ink. 10. The method according to one of claims 5 to 9, characterized in that said first, second and third layers (10, 11, 14) are attached to each other by laminating. |
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
[0001] This invention relates to a security document such as an identity card or drivers license, for instance.
DESCRIPTION OF PRIOR ART
[0002] Previously there are known security documents comprising an electronic module. The electronic module is embedded into the material of the security document, in many cases in such a way that it can not be visually detected from a surface of the security document.
[0003] A problem with the above described prior art solution is that the material of the security document may crack in an area close to the electronic module. Such cracking is caused by internal stress in the material of the security document.
[0004] One reason for internal stress is that the material of the security document and the material of the electronic module have different thermal expansion coefficients, in other words, the amount of expansion and shrinkage is different when temperature changes occur. SUMMARY OF THE INVENTION
[0005] An object of the present invention is to solve the above mentioned drawback and to provide a security document which has improved properties in order to avoid cracking. This object is achieved with a security document according to independent claim 1 and a method of manufacturing according to independent claim 5.
[0006] The possibility of utilizing at least a first separation layer slightly bigger than the hole with the electronic module to prevent layers on opposite sides of the separation layer from attaching to each other at least above or below the electronic module, results in a security document with improved properties. In this way a zone is created at least above or below the electronic module where the layers of the security document are not rigidly attached to each other. In this way internal stress and cracking can be avoided.
[0007] Preferred embodiments of the invention are disclosed in the dependent claims. BRIEF DESCRIPTION OF DRAWINGS
[0008] In the following the present invention will be described in closer detail by way of example and with reference to the attached drawings, in which
[0009] Figure 1 illustrates a first embodiment of a security document, and
[0010] Figures 2a to 2c illustrate a first embodiment for manufacturing a security document.
DESCRIPTION OF AT LEAST ONE EMBODIMENT
[0011] Figure 1 illustrates a first embodiment of a security document 1 . The document of Figure 1 may be a identity card, a drivers license or an information page for a passport, for instance.
[0012] The security document may be provided with a photograph 2 of the holder and written data 3 with information about the holder, for instance. In addition, the security document may contain a plurality of security elements in order to make forgery of the security document as difficult as possible.
[0013] The security document 1 is additionally provided with an electronic module 4, which may be embedded into the plastic material of the security document 1 , for instance. Typically the material of the security document is colored, in which case the electronic module is not visible from any side of the security document (though in some cases it might be possible to locate the module as a darker area compared to the surroundings when the security document is held up against a strong light source).
[0014] The security module may consist of one or more microcircuits for instance, and also an antenna coil may be embedded into the material of the security document in order to facilitate contactless communication between the electronic module 4 and an external apparatus.
[0015] Figures 2a to 2c illustrate a first embodiment for manufacturing a security document. The security document of Figure 1 may be manufactured according to this method. In the illustrated example it is by way of example assumed that separation layers are arranged both above and below the electronic module, though this is not necessary in all embodiments.
[0016] In Figure 2a a first layer 10 and a second layer 1 1 are provided. An area of the first layer 10 is covered by printing ink by printing in order to form a first separation layer 12. Similarly, an area of the second layer 1 1 is covered by printing ink by printing in order to form a second separation layer 13.
[0017] In Figure 2b a third layer 14 is provided. The third layer 14 has a hole 15 through it. An electronic module 4 is arranged into this hole.
[0018] The material of the first layer, second layer and third layer may be any suitable material for producing a security document. Typically plastic materials are utilized. One alternative is to produce all of these three layers of Polycarbonate, for instance. Possible additional layers may also be of Polycarbonate, or of alternative materials suitable for use in connection with Polycarbonate.
[0019] In Figure 2c the third layer 14 with the electronic module 4 is arranged between the first layer 10 and the second layer 1 1 . From Figure 2c it can be seen that the first separation layer 12 is slightly bigger that the hole such that the first separation layer 12 prevents the first layer 10 and the third layer 14 from attaching to each other (in a subsequent step) at the location of the hole 15 with the electronic module 4 and at the edges of the hole. Similarly, from Figure 2c it can be seen that the second separation layer 13 is slightly bigger that the hole 15 such that the second separation layer 13 prevents the second layer 1 1 and the third layer 14 from attaching to each other (in a subsequent step) at the location of the hole 15 and at the edges of the hole.
[0020] Once brought into the position as illustrated in Figure 2c, the layers 10, 1 1 and 14, and possibly additional layers which are not necessary but may be included as illustrated by way of example, are attached to each other. The attachment may be carried out by lamination, for instance, whereby the layers are pressed towards each other in a raised temperature. The first separation layer 12 and the second separation layer 13 prevent attachment above and under the electronic module 4, which results in a more reliable and durable security document. The separation layers may be used between other layers than those illustrated in Figure 2c by way of example. [0021] In the previous explanation it has, by way of example, been assumed that the first and second separation layers 12 and 13 are provided on the first and second layers 10 and 1 1 . However, one possibility is also to provide the first and second separation layers on opposite sides of the third layer 14 to cover the hole 15 and the electronic module 4.
[0022] Above it has also, by way of example, been assumed that the first and second separation layers are provided specifically by printing with printing ink. However, other alternatives exist both regarding the way to provide the separation layers and the material of the separation layers. Offset printing with an UV (Ultra Violet) curable printing ink, in other words a similar printing ink that is commonly used for coloring or printing various areas of prior art security cards has, however, turned out to be one advantageous alternative to provide the first and second separation layers. In this way separation layers with a thickness about 2 - 5 μιτι can easily and reliably be produced in exactly the correct position. In a security document where the thickness of the third layer 14 is about 350 - 400 μιτι such separation layers are thin enough not to change the shape of upper or lower surface of the security document at the location of the electronic module. Therefore it is not necessary to make any gaps or cavities (matching the size of the separation layers) for the separation layers in any one of the first, second or third layers. This results in a simple production process.
[0023] Naturally similar advantages are obtained also with other printable materials, as long as the material of the separation layers is capable of preventing rigid attachment of the first, second and third layers at the location of the hole and the edges of the hole. Therefore it is possible to use also other compounds than printing ink only, such as printing ink where some additional compounds have been added.
[0024] It is to be understood that the above description and the accompanying figures are only intended to illustrate the present invention. It will be obvious to a person skilled in the art that the invention can be varied and modified without departing from the scope of the invention.