Card with conductive ink

Abstract

The present invention provides a card 10 comprising at least two plastic layers and delimited by a first external face 12 and a second external face 14, the card 10 comprising a pattern 16 formed by a conductive ink deposited on an internal face of a plastic layer and sandwiched between two plastic layers, the conductive ink being intended to cooperate with a capacitive screen 18 for the generation of a signal 24 on the basis of the pattern 16, the first face 12 of the card 10 further comprises an adhesive coating 28 making it easier to hold the document on the capacitive screen 18 by opposing the force exerted during the movement of an input means 22 on the second face 14 of the card 10 so as to reduce the risk of the card 10 slipping on the capacitive screen 18. [Fig. 1]

Description

Title of the invention: Card with conductive ink

[0001] The invention relates to cards and more particularly to cards capable of generating a signal in cooperation with a capacitive touch screen, such as a mobile phone screen.

[0002] Cards comprising several conductive elements, formed by a conductive ink, all of the elements forming a pattern are known from the prior art. These conductive elements are embedded between two layers and are invisible to the user. The pattern formed by these conductive elements can be read by a capacitive touch screen, such as those traditionally used by devices such as mobile phones or touch tablets. When the pattern is read, the device detects and displays, on the screen, a signal specific to the pattern read.

[0003] The pattern is read when the card is positioned on the capacitive touch screen, during the relative movement by an input means, such as a finger or a stylus, on a part of the card located opposite the pattern. A set of sensors of the capacitive touch screen detects the movement of the input means and the electrical value associated with the conductive elements of the pattern. The difference in the electrical value read between the passage of the input means directly over the screen and the passage of the input means over the card placed on the screen makes it possible to extract a signal therefrom by the mobile phone which can be displayed on the screen.

[0004] However, it has been found that when moving the input means on the card, there is a significant risk that the card will be moved by the movement of the input means. Indeed, capacitive touch screens have a very smooth surface. When a plastic card is positioned on this type of screen, the card slips easily because there is little friction between the face of the card and the capacitive touch screen. In addition, a stylus or a finger has higher adhesion properties than those of the screen. As a result, the friction or adhesion in the contact area between the card and the screen is much lower than that resulting from the movement of a finger or a stylus on the upper face of the card, under normal conditions of use, that is to say with the application of pressure similar to that used by a finger on a smartphone screen.This results in a significant risk of the card moving when swiping with a finger or stylus.

[0005] Moving the card when reading the pattern causes a position shift of the elements making up the pattern. Consequently, the signal extracted from this reading procedure is therefore not correct. The signal is then processed to generate a code. The non-conformity of the signal results in the generation of a false code, which may prevent certain operations, such as access to data stored in the card's microprocessor or carrying out a transaction with this card.

[0006] It is therefore important to maintain the position of the map during the average movement of entry on the map.

[0007] To this end, the present invention proposes a card comprising at least two plastic layers and delimited by a first external face and a second external face, the card comprising a pattern formed by a conductive ink deposited on an internal face of a plastic layer and sandwiched between two plastic layers, the conductive ink being intended to cooperate with a capacitive screen for generating a signal on the basis of the pattern. The card is characterized in that the first face of the card further comprises an adhesive coating making it easier to hold the document on the capacitive screen by opposing the force exerted when moving an input means on the second face of the card so as to reduce the risk of the card slipping on the capacitive screen.

[0008] Thanks to these provisions, the adhesive coating greatly reduces, or even prevents, the sliding of the card on the capacitive screen, under the application of a displacement force equivalent to that of a finger or a stylus on a touch screen. It is then easier to hold the card in the desired position and to extract a reliable signal from it.

[0009] Other advantageous and non-limiting characteristics of the invention, taken individually or in all technically possible combinations, are the following:

[0010] the adhesive coating has adhesion properties to the capacitive touch screen superior to those of skin on plastic;

[0011] the coating is made of a gel-like material;

[0012] the coating is made of a solid material having a rough surface;

[0013] the coating covers the entire first face of the card;

[0014] the coating covers one or more areas of the first face of the card;

[0015] the zones are chosen in a direction substantially perpendicular to the direction of movement of the gripping means;

[0016] the coating is deposited in cavities dug in the thickness of the card;

[0017] the coating is deposited flush with the surface of the card;

[0018] The invention also relates to a method for manufacturing a card comprising the following steps: assembly of plastic layers by applying heat and under pressure so as to form a card body, deposition of the adhesive coating on the first face of the card.

[0019] Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the appended drawings which illustrate a non-limiting example of embodiment. In the figures:

[0020] - [Fig.l] represents a card according to the invention positioned on a telephone screen portable;

[0021] - [Fig.2a] and [Fig.2b] respectively illustrate the signals detected when the card is properly maintained when reading the pattern and when the card is moved while reading the pattern;

[0022] - [Fig.3] represents a first embodiment of the holding means;

[0023] - [Fig.4] represents a second embodiment of the holding means.

[0024] In the representation of the drawings, the scales and proportions are not respected in order to increase the clarity of the figures. In addition, in the figures listed above, similar features may have the same reference. The terms first and second may be interchanged without changing the function of the associated elements.

[0025] In [Fig.l], the card 10 according to the invention may be an identity card, a driving license, a bank card, a credit card, an identity card, an official document in the form of a booklet, such as a passport. These cards are linked to the holder of the document and may be used to verify the identity of their holder or to carry out an action, such as a transaction, in the name of the card holder.

[0026] Generally, these cards comprise a flat body delimited by a first external face 12 and a second external face 14 each having a surface area specified by established standards, such as the ID-1 format specified in the ISO7810 standard having the dimensions 85.60mm*53.98mm.

[0027] The card 10 comprises a body formed from several layers of PC, or PVC or PET or any combination of these materials. The layers are assembled by a lamination process known to those skilled in the art.

[0028] Traditionally, the card 10 comprises a microcircuit storing data specific to the holder of the card 10, considered to be confidential information. This confidential information may be information on the identity of the holder, or biometric information of the holder. The microcircuit may also store programs dedicated to specific operations, such as a transaction.

[0029] The card 10 according to the invention comprises a pattern 16 made of electrically conductive material, for example a pattern 16 printed with a conductive ink deposited on an internal face of a plastic layer. The pattern 16 is sandwiched between two plastic layers. The conductive ink is intended to cooperate with a capacitive screen 18 for reading the pattern 16. In [Fig.l], although the pattern 16 made of material electrically conductive is visible, this pattern 16 may be embedded between opaque or partially opaque layers, which makes it difficult for a third party to reproduce it. It will be noted that by pattern 16, we mean a particular shape and size of one or more electrically conductive elements, such as segments 20 as illustrated in [Fig.l].

[0030] This pattern 16 is composed of a plurality of segments 20 which are all spaced apart from each other, and therefore electrically insulated from each other. In the example illustrated, the elements are segments 20 which are all parallel, and they each have an offset from an axis perpendicular to the segments 20. It is understood that by modifying these offsets, it is possible to create a unique pattern 16 specific to the microcircuit card 10. Other patterns made of electrically conductive material can be used.

[0031] According to a preferred embodiment, the card 10 comprises a pattern 16 made of electrically conductive material configured so that when a first face 12 of the card 10 is placed against a surface of a capacitive sensitive touch screen 18, and a user comes into contact, with an input means 22, such as a finger or a stylus, with the second face 14 of the card 10 opposite the first face 12 according to a given contact movement, a signal 24 specific to the shape of the pattern 16 made of electrically conductive material and to the given contact movement is detected by the capacitive sensitive surface.

[0032] The element visible here is arranged between two electrically insulating regions, typically PVC layers. For example, if a conductive ink is used, it will be deposited at the interface between the two PVC layers.

[0033] Preferably but not limitingly, in the remainder of the description, the electrically conductive material is conductive ink. The term conductive ink or electrically conductive material is used hereinafter, one being able to be replaced by the other in a non-limiting manner. Preferably but not limitingly, in the remainder of the description, the layers of the card are formed from PVC. In other embodiments, the layers may be Polycarbonate, PETF or other polymers.

[0034] Although not visible here, the pattern 16 of electrically conductive material may be surrounded by a matrix of electrically conductive particles (metallic or organic), which have not been connected together by application of a laser beam to form part of the pattern 16 of electrically conductive material and its elements.

[0035] By choosing opaque or at least partially opaque layers, it can be made difficult for a third party to copy the pattern 16 made of electrically conductive material.

[0036] Also, and as explained in the prior document US 2020 / 0117972, the encapsulation of the pattern 16 in electrically conductive material makes it possible to implement a reading of the pattern 16 to carry out the detection of the signal 24 by the capacitive sensitive surface.

[0037] As can be seen in [Fig. 1], the first face 12 may be placed and in contact with a capacitive sensitive surface, and the second face 14 will be the face of the card 10 on which a user will make a contact movement.

[0038] The present invention is particularly concerned with reading the pattern 16 when moving the input means 22, the finger or the stylus, in a direction of movement 30 on the card 10. This direction of movement 30 is illustrated by the arrow in [Fig. 1]. In order to guide the user to move the input means 22 on a part of the first face 12 opposite the pattern 16, a printed border 32 is produced and visible from the second face 14 of the card 10. This border 32 is illustrated in dotted lines in [Fig. 1]. The arrow indicating the direction of movement 30 can also, optionally, be printed and visible from the second face 14 of the card.

[0039] To correctly read the pattern 16 when the input means 22 is moved, it is necessary to hold the card 10 firmly on the capacitive touch screen 18 so that the card 10 remains in the same position relative to the screen 18 for the entire duration of the movement of the input means 22.

[0040] Indeed, a movement of the card 10 on the screen 18, during the duration of the entry of the pattern 16 causes a shift of certain parts of the pattern 16 read and consequently the detection of a signal 24 different from that which should have been theoretically detected. The signal 24 is then incorrect and this can prevent the validation of an action linked to the card 10.

[0041] Figures 2a and 2b each illustrate, schematically, a device each displaying a signal 24 recovered on the interface of the capacitive touch screen 18. A specific application integrated into the capture device processes this recovered signal 24 to generate a code. This code is not displayed on the screen 18 in the actual acquisition procedure, only the signal 24 will be displayed to determine whether the latter is correct or incorrect.

[0042] In the captures of figures 2a and 2b, the trace 26 located at the bottom of the screen 18 represents all the positions of the holding finger, which was used to hold the document, during the scanning of the card 10 by the input element.

[0043] In [Fig.2a], the trace 26 is very small, which means that the holding finger has hardly moved in position. This indicates that the card 10 has not slipped or has slipped very little during the movement of the gripping element, and the signal 24 detected by the screen 18 capacitive touch forms a continuous curve and therefore allows the calculation of the code used later.

[0044] In [Fig.2b], the trace 26 is larger than that of [Fig.2a], and exceeds the limits indicated by a circle. This means that the holding finger has moved from its position. In addition, the signal 24 detected and displayed by the screen 18 is discontinuous. This signal 24 is the result of a scan of the card 10 while the latter has slid on the capacitive touch screen 18 during the scan. In this case, the signal 24 includes interruptions which will be taken into account during its processing to extract the code. The code, associated with this interrupted signal 24, is then incorrect. The actions linked to the verification of this code are, consequently, not authorized.

[0045] It therefore appeared necessary to add one or more gripping or non-slip zones to limit, or even prevent, any sliding of the card 10 on the screen 18 when scanning it.

[0046] Capacitive touch screens 18 usually have a very smooth surface without any roughness. The card 10 has two smooth polymer faces. These conditions therefore promote the sliding of the card 10 on the capacitive touch screen 18, especially when an external element moves on one face of the card 10. It is then necessary for the user to hold the card 10 on the screen 18 with one hand and use the other hand to move the input means 22 along the card 10.

[0047] This position is restrictive for the user and the present invention seeks to facilitate the operation of reading the signal 24 carried out by the user.

[0048] To this end, the invention relates to a card 10 as described above in which the first face 12 of the card 10 further comprises an adhesive coating 28 allowing the document to be held on the capacitive screen 18 when a force is applied by passing a finger over the second face 14 of the card 10 so as to reduce the risk of the card 10 sliding on the capacitive screen 18.

[0049] The adhesive coating 28 has the function of increasing the adhesion between the face of the card 10 and the capacitive touch screen 18 on which the card 10 is positioned. The term "adhesion" means all the forces which are exerted between the card 10 and the capacitive touch screen 18, in close contact, and which prevent them from sliding against each other. Thus the forces exerted by the adhesive coating 28 are greater than the forces exerted on the card 10 when the gripping means 22 passes over the pattern 16. The adhesive coating 28 has the effect of opposing the forces exerted by the gripping means 22 which can cause the card 10 to slide. The coating 28 thus has an anti-slip function.

[0050] According to a variant, the adhesive coating 28 has adhesion properties to the capacitive touch screen 18 which are superior to the adhesion properties of the skin on the plastic.

[0051] The adhesion between the card 10 and the capacitive touch screen 18 is chosen so that the force (or thrust) exerted by the finger does not cause any movement and that there are sufficient forces to keep the card 10 stationary on the capacitive touch screen 18. More particularly, the adhesive coating 28 is chosen so that the adhesion properties to the screen 18 are greater than the adhesion properties of the skin on the plastic forming the surface of the card 10.

[0052] According to one embodiment, the coating 28 is made of a material in the form of a gel, exhibiting no flow when it is in a stable state. For example, the gel may be polyurethane, silicone, or PVC.

[0053] According to another embodiment, the coating 28 is made of a solid material having a rough surface having asperities creating small elementary contact forces increasing the adhesion on the capacitive touch screen 18. For example, this is obtained by changing the properties of the smooth surface of the material by creating micro holes or cavities by cutting, sanding or even flaming.

[0054] The adhesive coating 28 is irreversibly deposited on the first face 12 of the card 10 intended to come into contact with the capacitive touch screen 18. The addition of this material is done after the manufacturing step of the card 10, that is to say after the lamination phase in the factory. Preferably, the material constituting the adhesive coating 28 is transparent to allow a printing layer produced on one of the internal layers of the card 10 to be viewed.

[0055] The coating 28 is deposited on the first face 12 of the card 10 in liquid form, then is crosslinked by applying heat or radiation to form a solid layer or a layer in gel form. The adherent coating 28, after crosslinking, has adhesion properties as described further in the description.

[0056] According to a first manufacturing method, the coating 28 is deposited over the entire first face 12 of the card 10, that is to say that the adhesive coating 28 extends to the edges delimiting the card 10. In this case, the adhesive coating 28 then constitutes an additional layer covering the plastic substrate.

[0057] According to a second manufacturing method, the coating 28 is deposited on the first face 12 of the card 10 only on determined zones 34. [Fig. 4] illustrates an example of this manufacturing method in which two eccentric zones 34 of the face are covered with the adherent coating 28. Preferably these zones 34 are substantially aligned along an axis perpendicular to the direction of movement 30 of the gripping means 22 to oppose the forces created by the movement of the gripping means 22.

[0058] According to a variant of the second manufacturing method, the coating 28 is deposited in one or more cavities 36 opening into the first face 12 of the card 10. The cavity 36 is hollowed out in the thickness of the card 10, by a milling machine, according to a method known to those skilled in the art, in a predetermined area of ​​the card 10. The material forming the coating 28 is deposited in the cavity 36 to cover the area. Advantageously, the coating 28 is deposited in the form of a liquid or gel which, upon cooling or drying, becomes a solid or a gel in a stable state without flow. The deposition in the cavity 36 will ensure that the coating 28 is flush with or emerges very slightly (5 to 20 μm) from the face of the card 10. The coating 28 therefore constitutes a relief on the document but as thin as possible so as not to move the pattern 16 too far from the surface of the capacitive screen 18. Preferably, the cavities 36 are substantially aligned along an axis perpendicular to the direction of movement 30 of the gripping means 22 to oppose the forces created by the movement of the gripping means 22.

[0059] It is entirely possible to combine one or other of the embodiments with the manufacturing methods and variants described further on. The choice of manufacturing method or variants will depend on the shape of the pattern 16 and the properties of the materials chosen for the coating 28 and the card body 10.

[0060] The invention also relates to a method for manufacturing a card 10 according to the invention. The manufacturing method comprises a preliminary step of forming a card body 10 by assembling under pressure and applying heat at least two plastic layers. One of the layers may have printing on one of its faces. Then the card body 10. Figures 3 and 4 illustrate a card body 10 comprising seven plastic layers. Traditionally, the seven layers are distributed as follows: two transparent external layers, called overlay, two printing layers located respectively under the external layers, and three layers forming an inlay composed of a layer for embedding a wire antenna, and two protective layers located above and below the layer receiving the antenna.In the present invention, the print layer visible from the second face 14 comprises a guide path for the input means 22 to guide the user to move the input means 22 on the card 10. This path is represented by the oblong shape and the arrow both drawn in dotted lines. The structure of the card body 10 is given only by way of example, and the invention is in no way limited to this structure. The card 10 may further comprise a chip connected to the ends of the antenna and positioned either in the card body 10, or on a module positioned in one or more cavities 36 made in the card body 10.

[0061] Next, a step of depositing a material forming an adherent coating 28 is carried out, either locally on determined areas of the card 10, or over the entire surface of the card 10. According to the variant illustrated in [Fig.4], a milling step of one or more cavities 36 for receiving the coating 28 is produced prior to deposition.

Claims

Claims

1. Card (10) comprising at least two plastic layers and delimited by a first external face (12) and a second external face (14), the card (10) comprising a pattern (16) formed by a conductive ink deposited on an internal face of a plastic layer and sandwiched between two plastic layers, the conductive ink being intended to cooperate with a capacitive screen (18) for the generation of a signal (24) on the basis of the pattern (16), characterized in that the first face (12) of the card (10) further comprises an adhesive coating (28) making it easier to hold the card on the capacitive screen (18) by opposing the force exerted when moving a gripping means (22) on the second face (14) of the card (10) so as to reduce the risk of the card (10) slipping on the capacitive screen (18).

2. Card (10) according to the preceding claim, in which the adhesive coating (28) has adhesion properties to the capacitive touch screen (18), that is to say properties such that a set of forces exerted between the coating (28) and the capacitive touch screen (18) opposes the sliding of the coating (28) against the screen (18), these adhesion properties being greater than those of the skin on the plastic of the card.

3. Card (10) according to one of the preceding claims, in which the coating (28) is made of a gel-like material.

4. A card (10) according to either of claims 1 or 2, wherein the coating (28) is made of a solid material having a rough surface.

5. Card (10) according to one of the preceding claims, in which the coating (28) covers the entire first face (12) of the card (10).

6. Card (10) according to one of claims 1 to 4, in which the coating (28) covers one or more areas (34) of the first face (12) of the card (10).

7. Card (10) according to the preceding claim in which the zones (34) are chosen in a direction substantially perpendicular to the direction of movement (30) of the input means (22).

8. Card (10) according to one of claims 6 or 7, in which the coating (28) is deposited in cavities (36) hollowed out in the thickness of the card (10).

9. Card (10) according to claim 8, in which the coating is deposited flush with the surface of the card (10).

10. Method of manufacturing a card (10) according to claim 1 comprising the following steps - assembly of plastic layers by applying heat and under pressure so as to form a card body (10) - deposition of the adhesive coating (28) on the first face (12) of the card (10).

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