WO1999050786A1 - Medium bearing encoding means for its authentication and rereading device for same - Google Patents

Abstract

The invention concerns a medium such as a banknote, an administrative document or credit card bearing encoding means for its authentication, characterised in that the encoding means contain thermally sensitive liquid crystals.

Description

“Support carrying coding means allowing its authentication as well as device for re-reading such a support. "

The present invention relates to a support carrying coding means allowing its authentication.

We already know different means of coding documents that can be counterfeited (banknotes, administrative documents, credit cards, - ...) intended to prevent their reproduction and fraudulent use, and therefore to ensure the security of their transmitter and holder.

The object of the present invention is to provide a support provided with such a coding means, supplemented by dactyl coding means for the visually impaired.

According to the invention, this support is characterized in that the coding means contain thermosensitive liquid crystals.

These liquid crystals can be identified at a given temperature at which they give, by thermal contact, a light spectrum allowing the authentication of the support.

It should be noted that, in accordance with a variant of the invention, the coding can be identified by virtue of its apparent color following a simple touch at human temperature (36/37 °), which allows very rapid authentication.

The support according to the invention can be of the aforementioned type, but also of another type (paintings, valuables, automobiles, ...).

According to another characteristic of the invention, the heat-sensitive liquid crystals are inserted into a coding plate integrated into the support.

Such a plate can be embedded or fixed in an irremovable manner on the support.

In accordance with the invention, the heat-sensitive liquid crystal coding means can be associated with other coding means such as coded multi-point engravings produced on the coding plate, in particular using a punch or even laser.

Such coded multi-point engravings are, for example described in the publication FR-2 667 825. The invention also relates to a device for reading a support of the aforementioned type.

Such a device is characterized in that it includes thermal and chromatic reading devices adjusted to a precise predetermined temperature as a function of the medium to be authenticated and equipped with a thermal reading contact element which, at this predetermined temperature, allows 'identify the light spectrum given by liquid crystals. According to the invention, the thermal re-reading contact element ensures, at a predetermined temperature, the re-reading of a precise slice of liquid crystals and verifies the correspondence of their color with the initially predetermined color. According to another characteristic of the invention, the device comprises members for the optical reading of coded multipoint etchings.

The replay device according to the invention is, as a general rule, equipped with belt drive members capable, from an entry station, of transferring the medium to be authenticated to the right of the thermal replay devices and chromatic and, where appropriate, at the level of the optical proofing bodies and then to an exit station. These belt drive members may advantageously include studs or electromagnetic bars capable of gripping the support to be authenticated and of guiding it to the right of the various stations.

The drive members can also be constituted by a drive belt doubling the main belt so that the supports to be authenticated are taken between the two belts and thus transported between the different detection and replay stations.

It should be noted that to guarantee the authenticity of the media to be reread, it is essential that the device be inviolable: any attempt to open it leads to an immediate deregulation of the rereading system, which has the consequence of disabling it; therefore, any attempt reproduction of this device is impossible and its adjustment remains secret.

According to other advantageous characteristics of the invention: - the device comprises a double belt, a main belt, passing over two cylinders constituting the path for circulation of the products to be authenticated and an external belt, passing over rollers, around the inner belt so as to form a circulation path around the belt and hold the products to be detected in the interval between the two belts.

the roller located in the thermal and chromatic detection station comprises a heating means radiating towards the external surface of the roller to heat the supports to be authenticated passing through the area,

- The roller has an outer surface forming a double envelope supplied with heat transfer fluid from the heating source placed in the center of the roller.

The characteristics of the support as well as of the replay device, which are the subject of the invention, will be described in more detail with reference to the appended figures in which:

- Figure 1 is a diagram representing this device, - Figure 2 shows an alternative embodiment of the invention.

In accordance with FIG. 1, the device comprises an endless drive belt 1 guided in translation by drive wheels 2, 3 movable in rotation according to arrows a and b so as to transfer the support to be authenticated from a station input I to an optical replay station II then to a thermal and chromatic replay station III.

The drive belt 1 cooperates with an auxiliary endless drive belt 4 guided in translation by auxiliary drive wheels 5, 6 and 7 movable in rotation according to the arrows c and d. The auxiliary drive belt 4 transfers the media to authenticate from the thermal and chromatic reading station III to an exit station IV.

According to the figure, the support to be authenticated penetrating along the arrow A into the device at the entry station I is gripped by pads or electromagnetic bars 8 _1; 8 ₂ , 8 ₃ , 8 ₄ and 85 fixed on the belts 1, 4 in order to be guided to the right of the different posts II, III and IV.

The studs or bars 8-L, 8 ₂ , 83, 8 ₄ , 8 ₅ are activated by contact on the wheels 2, 3, 5, 6, 7 as well as on contact plates 9, 10 and 11 associated with the belts without end represented by hatched on the figure and function like electromagnets.

After re-reading, the document is released according to arrow B at the exit station IV. At the optical replay station II, the support to be authenticated is caught between the contact plate 9 and a transparent plate 12 so as to allow optimal optical replay of the coded multi-point engravings. At the thermal and chromatic re-reading station III, the support is detected by a thermal re-reading contact element represented schematically by the double arrows C and C ₂ which, at predetermined temperature, ensures the re-reading of a precise slice of liquid crystals and checks the correspondence of the light spectrum given by them with an initially determined spectrum.

Figure 2 shows an alternative embodiment of the device of Figure 1. This variant includes, like the device of Figure 1, an endless drive belt 1 or main belt, guided by movable drive wheels 2, 3A in rotation according to the arrows a, b to drive the medium to be authenticated between the different stations, namely an input station I, an optical replay station II, a thermal and chromatic replay station III.

The drive belt 1, or main belt, is combined with an auxiliary belt 100 which surrounds the main belt 1 over practically all of its path. roof between rollers 2 and 3. This auxiliary belt 100 passes over drive and guide rollers 101, 102, 103, 104, 105, 106 rotating in the people indicated by the arrows. This belt 100 rotates in the same direction and the same speed as the belt 1 in the various places where it is opposite the belt 1.

Thus, from the entry station 1, the supports to be authenticated are taken between the two belts. The auxiliary belt 100 is preferably transparent. In certain cases, it is advantageous that the main belt 1 is also transparent, which makes it possible for example to carry out a recognition of the support on the two sides in the station II as indicated by the symbols AU, BII placed respectively at above and below the two belts 1, 100.

This solution then removes the rollers 5, 6, 7 and the lower belt.

The roller 3A, on which the double strip passes and which is associated with the thermal and chromatic reading station III, in the center of the roller there is a resistance heating element 31 which for example radiates on the periphery 32 of the roller . This roller is also provided with spokes 33 or partitions for a better efficiency of heat exchange. The roller 3A can also have a double wall 32, 33 and a heat transfer liquid can then be passed through the jacket thus formed, this liquid communicating with the heating means 31.

This variant embodiment is advantageous in certain cases since the authenticated product remains flat between the belt 1 and the belt 100.

The protection of the device according to the invention being mainly linked to the secrecy of the detection temperature, it is essential to avoid the possibility of introducing means inside the device making it possible to detect this temperature and by following to counterfeit the security means. For this, the introduction slot is relatively narrow and especially at the level of the recognition station II, any foreign element is detected. This detection immediately stops the installation or neutralizes it. Even a very fine temperature sensor - which would be introduced in this way - could not reach thermal and chromic detection in zone III and know the temperature at which this detection is made.

For the same safety concern, the device is mounted in such a way as to destroy or render inoperative the vital parts of the installation, i.e. thermal and chromic detection always so as not to allow the exact temperature to be known. at which detection takes place, a temperature which corresponds to the strategic element in this installation and more generally in the authentication and counterfeit system, which the present invention should allow.

Thus, in the event of a detection element or parasitic element introduced into the machine, there is almost certain detection of this intrusion into station II. If despite the very high precision and efficiency of this station II, the detection object nevertheless continues on its way and arrives in station III, then the thermal and chromatic reading means make it possible to detect this intrusion. This detection automatically takes countermeasures against this intrusion.

Still in order to avoid disclosing as little as possible the temperature which is necessary for detection in station III, a partition 107 is provided, crossed by the belts 1 and 100 by two slots. The purpose of this thermal insulation partition 107 is to confine the heat source at the level of the roller 3A, to prevent it from diffusing too much.

Still in the same spirit, in the zone at the front of the partition 107, there is provided a fan 108 intended to lower the temperature in this zone.

Finally, it should be noted that the reading and detection zones are advantageously preprogrammed secretly depending on the nature of the media or products to be authenticated. This corresponds to additional security, linked to proofreading in addition to the security existing elsewhere and linked to engraving.

Claims

R E V E N D I C A T I O N S 1 °) Support such as bank note, administrative document or credit card carrying coding means allowing its authentication, characterized in that the coding means contain thermosensitive liquid crystals. 2 °) Support according to claim 1, characterized in that the heat-sensitive liquid crystals are inserted in a coding plate integrated into the support. 3) Support according to claim 2, characterized in that the coding plate comprises coded multi-point engravings. 4 °) device for re-reading a support according to any one of claims 1 to 3, characterized in that it comprises thermal and chromatic re-reading members (III) adjusted to a precise temperature predetermined according to the support to be authenticated and fitted with a thermal replay contact element (C _{1 #} C ₂ ) which, at this predetermined temperature, makes it possible to identify the light spectrum given by the liquid crystals. 5 °) Device according to claim 4, characterized in that it comprises optical replay members (II) of coded multipoint etchings. 6 °) Device according to claims 4 and 5, characterized in that it comprises belt drive members (14) capable, from an input station (I), of transferring the medium to be authenticated to law of thermal and chromatic proofreading organs (III) and, where applicable, law optical reading devices (II) then to an exit station (IV). 7 °) Device according to claim 6, characterized in that the belt drive members (1, 4) comprise pads or electromagnetic bars (8 _{1 #} 8, 8 ₃ , 8 ₄ , 8 ₅ ) capable of gripping the support to authenticate and guide it to the right of the different positions. 8 °) Device according to claim 6, characterized in that it comprises a double belt, a main belt (1), passing over two cylinders (2, 3) constituting the circulation path of the products to be authenticated and of a belt outer (100), passing on rollers (101-106), around the inner belt (1) so as to form a circulation path around the belt (1) and keep the products to be detected in the interval between the two belts. 9 °) Device according to claim 6, characterized in that the roller (3A) located in the thermal and chromatic detection station (III) comprises a heating means radiating towards the external surface of the roller to heat the supports to be authenticated passing through zone (3). 10 °) Device according to claim 9, characterized in that the roller (3A) has an outer surface forming a double envelope supplied with heat transfer fluid from the heating source placed in the center of the roller.