FR2937456A1 - DEVICE, IN PARTICULAR LABEL, OF SAFETY FOR AUTHENTICATING A PRODUCT. - Google Patents

Abstract

This security device, in the form of a label for product authentication, comprises a single or multiple transparent support (1), coated with a transparent layer of pressure-sensitive adhesive (2), a printing zone (3) applied directly to said adhesive layer (2), the layer (2) being applied to the product (5) to be authenticated. The security device is characterized in that, after adhesion to the product to be authenticated, any attempt to detach by manual, mechanical, thermal or chemical means causes the irreversible destruction of the printing zone (3) by cohesive rupture of the adhesive layer (2) whose cohesive strength is less than the adhesive force.

Description

Device, in particular security tag, for authenticating a product

The present invention relates to a security device for the authentication of products, and in particular a device constituted by a security tag intended to be affixed to products or articles whose origin or membership is to be authenticated, such as, for example, license plates of motor vehicles. The tag may also be used as a tamper or tamper evidence for a container whose content integrity is desired.

Most of the marketed items or intermediate parts of the industry are identified with self-adhesive labels, glued directly to the item or stuck on the packaging. Simultaneously with the information provided on the nature and characteristics of said article, this label usually indicates the origin and the name of the manufacturer.

However, in certain industrial sectors, such as the automotive industry, it is now essential to guarantee the origin of spare parts or identification articles to prevent falsification or counterfeiting.

In addition to the well-known securing methods (for example embrittlement of one or more layers so that, in an attempt to detach, the different layers separate or tear apart), one of the proposed solutions consists of self-adhesive labels. adhesive strips having a plurality of layers printed on at least two sides with different adhesives inks, so that, in an attempt to detach, one of the printed areas is transferred to the back of the upper layer. Such a type of label is described in US4180929.

Similarly, the patent EP0375602 describes a printed product having the configuration of a label, showing a falsification after application to a support, the falsification indication being made by two bonded surfaces, one being a support layer of printed ink which, at any attempt of separation, causes a transfer from one surface to another.

For security labels providing proof of the fraudulent opening of a product, patent EP0773889 describes the principle of a closure comprising an adhesive layer applied to a surface, a support on which portions of the adhesive layer stick when said device is applied, and indicating means disposed on the support so as to be between the adhesive layer and the support. For the protection of a document against forgery, the patent FR2675742 describes a thin transparent protective film comprising a transparent adhesive layer. Between the protective film and the adhesive layer is interposed continuous or discontinuous printing by means of an ink containing a hydrocarbon-soluble dye. This impression makes it possible to detect any attempt to separate the film by means of a solvent.

Another way of ensuring the security function of a tag is to include microcapsules in the silicone layer of the protective support in contact with the adhesive layer, as described in patent application WO9746378. Before bonding to the product to be authenticated, the protective support is pressed against the adhesive layer, thus releasing easily identifiable marker agents on the adhesive layer.

Another type of security tag for authenticating a product is disclosed in US6361079 in the form of an adhesive backing printed on both sides, the upper face having a print area visible to natural light to inform the product. consumer, while the lower adhesive side is printed using a visible ink only with a specific wavelength radiation.

For the production of a secure identification label for a motor vehicle, the patent FR2862416 describes a complex sheet consisting of a transparent adhesive label comprising a vitrophane information display area printed under the support and a second zone. specific printable and repositionable prints. The device provides viewing means for attempting to remove the adhesive label with a control adhesive leaving visible traces or by a weakening support. However, all of these inventions, having impressions directly attached to the label support, provide little protection against forgery despite the complexity of their implementation. Indeed, fraudsters today have advanced mechanical or chemical means 10 to take off and manipulate even very thin films. They can thus take off from the original product to authenticate the label without degrading the characteristics or security devices, then postpone the label on another counterfeit product or falsified, suggesting that this product is original, since it bears a label of security itself authentic.

The object of the present invention is to propose a device for authenticating products which does not have the drawbacks of the prior art, and offers an effective security device against fraud attempts while remaining simple to carry out.

The invention achieves its goal by means of a security device for the authentication of a product intended to be applied on a surface of the product, of the type comprising a transparent support having a first face and a second face, coated on its surface. second face of a transparent layer of adhesive having a first face and a second face, said first face of the adhesive being in contact with said second face of the support, and said second face of the adhesive being intended to adhere to the product surface, one of said faces of the adhesive layer comprising a first zone on which is directly applied an impression and a second zone free from said printing, said printing being intended to authenticate the product, characterized in that said printing is provided on said second face of the adhesive layer, the adhesive power of the device on said product being greater than the cohesive power of the adhesive layer. adhesive, whereby an attempt to remove the security device from the product leads to a cohesive failure of the adhesive layer, the distribution of the printing area within the print-free area being such that a cohesive failure of the adhesive layer leaves at least a portion of said adhesive bonded to said product.

The adhesive strength of the device on the product depends not only on the adhesive and the product, but also the support of the device. The person skilled in the art knows, by means of simple tests, to experimentally determine if a device satisfies the conditions imposed above: it suffices to observe the behavior of a sample of the device during an adhesive power test, according to one of the many standard methods of measurement, for example when measuring the peel strength at 90 ° according to the standard AFERA 5001 (Association of European Manufacturers of Self Adhesive Tapes), to find out there is cohesive rupture before reaching the force causing the detachment.

In other words, according to the invention, a security impression is made directly on the face of the adhesive layer which is in contact with the product to be authenticated, the adhesive being thus chosen according to the other elements of the device. with a cohesive power lower than its adhesive power so as to ensure that in the event of an attempt to remove (by tearing or peeling or other operation) of said device, the printing area remains totally or at least partially attached to the product and can be completely removed with the safety device for reuse elsewhere.

Thus, according to the invention, the printing zone is destroyed (of the security device itself) partially or totally during any attempt to detach, shear or separate the device from the support of the product to be authenticated, by any means manual, mechanical, thermal or chemical.

Of course, the print area and the print-free area can each be made up of several disjoint regions or surfaces. The printing regions may in particular be constituted by islands within a zone that is free of printing. Advantageously, the 90 ° peel force of the device which reflects the adhesive power is greater than 3 N / cm (standard AFERA 5001). According to the invention, and unlike some known devices, the important thing is not to make a safety device that does not come off, but a device that, if it is taken off, is destroyed at least partially so that it can not be reused to authenticate another product. Naturally, for certain applications, it is preferable to have a higher peel strength, for example at 5 N / cm or even 10 N / cm.

Advantageously, the adhesive is chosen from elastomer or acrylic pressure-sensitive adhesives, in the solvent phase, aqueous phase or hot-meit type, and the person skilled in the art knows how to choose among them those which have an adhesion power corresponding to desired applications and a cohesive power lower than said adhesive power. The device of the invention comprises, before use on the product to be identified, a non-stick protector disposed on the adhesive layer which presents the printing zone.

Other characteristics and advantages of the invention will emerge on reading the following description of an embodiment, with reference to the appended drawings, in which:

- Figure 1 is a schematic sectional view of a device according to the invention presented before use on its non-stick protector.

- Figure 2 is a schematic sectional view of a device according to the invention applied to the bonding substrate of the product to be authenticated.

- Figures 3 and 4 are schematic sectional views of the principle of application of the invention during an attempt to detach the device with a sharp object. - Figure 5 is a variant of Figure 4 illustrating the result of an attempt to detach the device by a non-rectilinear cut with a sharp object. - Figures 6 and 7 are schematic sectional views of the principle of application of the invention during an attempt to detach the device with a jet of liquid or gas at high pressure.

- Figures 8 and 9 are schematic sectional views of the principle 10 of application of the invention during an attempt to detach the device with a solvent.

The device according to the invention and shown in FIG. 1 comprises a transparent support 1 with two faces 1a and 1b, the lower face 1b of which is coated with a transparent layer 2 of pressure-sensitive adhesive having two faces 2a, 2b, the latter being intended to be bonded by contact with the surface of a product to be authenticated. The thickness of the adhesive layer 2 is preferably between 10 m and 200 m. Authentication printing 3 is applied directly to the face 2b of the adhesive layer 2, in a printed area of said surface. The thickness of the printing 3 is for example from 1 m to 50 m. The distribution between the printed area and the unprinted complementary area is chosen to allow on the one hand the necessary adhesion to the surface of the product, in the period of use of the device, and on the other hand that the printed area is carried away At least partially during an attempt to tear the device as will be seen later; it is indeed the presence of the entire print 3 visible through the layers 1 and 2 that guarantees according to the invention the authenticity of the product, while the observation of a reduced print only to a part from what it must be translated an attempt at fraud. In practice, it is sufficient that the dimensions of each individual surface of the printed area be fairly small and / or narrow relative to the adjacent unprinted area to ensure that it will not be possible to completely remove the printed areas in case tearing of the label, insofar as at least a portion of the printed areas will remain attached to a sticky area that remains attached to the product after cohesive failure of the adhesive layer.

A non-stick protector 4 (for example a paper or a silicone film of the standard type) is applied to the adhesive layer 2 after printing of said adhesive layer 2 by ink or varnish 3, while waiting for It can be removed for the use of the device on the surface of the product to be authenticated represented here by its single bonding substrate (see FIG. 2).

Support 1 is a transparent film based on cellulose or polymers, for example: tracing paper, polyethylene, polypropylene, coextruded polyolefin, polyester, PVC, polyurethane, polystyrene, polycarbonate, polyamide, etc. Its thickness is for example 10 m to 5 mm.

The support 1 may consist of one or more transparent layers, partially or totally adhesive on each other, possibly separated by partial or total prints or varnishes. This layer or layers may previously comprise authentication elements, such as: iridescent or fluorescent elements printed or included in the support, thermal or chemical reagent, incorporation of holographic image by hot or cold foil stamping, printing with using a security ink, such as for example a color-changing ink under the effect of heat or at the viewing angle, optically variable impressions (OVI) with or without filters, etc. Advantageously, the support 1 may also contain a prior embrittlement, for example in the form of blanks or pre-cuts in its thickness in order to weaken it under the effect of mechanical traction.

The adhesive layer 2 coated on the support 1 is transparent.

The stack of the support 1 and the adhesive layer 2 is sufficiently transparent so as to allow the visualization, with the aid of optical means (magnifying glass or microscope, etc.), of the presence of the printing 3 through this stack of the support 1 and the adhesive layer 2.

The adhesive layer 2 coated on the support 1 is composed of a pressure-sensitive adhesive of standard type, of acrylic or elastomer base, according to a conventional solvent or water-based technology, or according to a type of technology. hot melt. Preferably, the composition of the adhesive has a low or medium cohesion to facilitate its disintegration in thickness under the effect of a mechanical or chemical stress. The composition of the adhesive is such that it allows the attachment of the device of the invention to the product to be authenticated for a long time, for the entire life of said product 5. According to an essential characteristic of the invention, the adhesion strength of the adhesive layer 2 and the printing 3 on the bonding substrate of the product to be authenticated (and possibly the adhesive force of the adhesive layer 2 on the support 1) is greater than the force required to generate a cohesive failure of the adhesive layer 2. Thus, during a mechanical or chemical stress of the device according to the invention applied to the bonding substrate of the product to be authenticated, there is a break cohesive layer of the adhesive layer 2: a portion of the adhesive layer 2 and the printing 3 remains attached to the support 1, the other to the bonding substrate 5 of the product to be authenticated, as shown in Figure 5. L skilled in the art knows how to choose a adhesive suitable for this purpose, as will be seen later by examples.

The printing 3, applied directly in mirror (vitrophanie) on the adhesive layer 2, can be achieved by all the conventional printing technologies called by contact with the adhesive layer 2, for example: flexography, typography, etc., or by unconventional printing technologies said to be non-contact with the adhesive layer 2, for example: digital printing, laser, inkjet, etc.

The ink or varnish used to carry out the printing 3 may be a so-called standard ink or varnish or a security ink or varnish comprising, for example, iridescent, luminescent, photo-luminescent, phosphorescent or fluorescent elements, tracers or chemical or thermal reagents, elements detectable by filter or radiation, optically variable elements (OVI) with or without filters, etc. It may also be inks or varnishes with color modification under the action of radiation (eg a laser beam).

Printing 3 applied directly to the adhesive layer 2 can also reproduce unique and non-reproducible alphanumeric data (for example random impressions, coded numbering, guilloche, micro-prints, hidden words or coded words, etc.) by means of the printing technologies and inks mentioned above.

~ o Printing 3 remains visible or at least detectable throughout the life of the product on its bonding substrate 5.

The nature and the physicochemical characteristics of the support 1, the adhesive layer 2 and the printing 3 are chosen by those skilled in the art as a function of the stresses and external stresses (for example ultra violet radiation resistance). (UV), temperature, humidity, gaseous atmosphere, etc.) to which the invention will be subjected throughout its lifetime. In particular, the presence and visualization of the entire print 3 through the stack of the support 1 and the adhesive layer 2 will not be altered by these external stresses and stresses.

FIGS. 3, 4 and 5 show the principle of operation of said label during an attempt to detach with the aid of a sharp cutting object 6, of the cutter or razor blade type, the cutting being able to be carried out in a manner 25 uniform and substantially straight (Figure 4) or not (Figure 5). This attempt to detach can be facilitated by the cross-use of a thermal means for example a hair dryer or a manual means (for example a fingernail). The adhesive layer 2 is cut partially in slice in its thickness. Part of the adhesive mass remains on the support of the product 3o 5 to authenticate, another part of the adhesive mass remaining on the support 1 of the label. In one case, shown in FIG. 4, the whole of the label is separated clearly at the level of the adhesive mass 2, and all the impressions 3 remain on the authentic product 5. In another case, as represented in FIG. 5, the cut is irregular and some of the prints are removed at the same time as the support 1 of the label, but a remaining part remains bound to adhesive parts glued to the authentic product 5, so that the prints 3 which have could be removed with the support 1 of the label are incomplete or altered.

Thus, during an attempt to detach, even if the support 1 of the label remains intact despite its weakening elements constituted by the internal cuts, the impression 3 made directly on the adhesive layer 2 can not be recovered in its entirety with the support 1 of the label, which will prohibit the reuse of said label with the initial printing 3. In ~ o effect, in case of reuse, the absence (Figure 4) or the alteration (Figure 5) of the print 3 made on the adhesive layer 2 can be easily highlighted with the naked eye or using an optical instrument (magnifying glass or microscope for example).

FIGS. 6 and 7 show the principle of operation of said label during an attempt to detach with a jet of liquid or high-pressure gas (for example high-pressure cleaner 7). The adhesive layer 2 and the printing 3 that it comprises will gradually cut or disintegrate. There will therefore be an irreversible alteration of this impression 3 which can not be recovered in full with the support 1 of the label, which will prohibit its reuse. Indeed, as in the previous case, in case of reuse, the absence or the alteration of this impression 3 made on the adhesive layer 2 can be easily highlighted with the naked eye or the help of an optical instrument. Figures 8 and 9 show the principle of operation of said label in an attempt to delaminate with solvents (eg acetone, alcohol, heptane, etc.). Under the action of these solvents, the adhesive layer 2 and the printing 3 that it comprises will gradually dissolve, dilute or degrade. There will therefore be an irreversible alteration of this impression 3 as in the previous cases.

We will now describe more specific examples of manufacture of a device according to the invention. In the case where the product bonding substrate 5 is a retro-reflective film of the 3M supplier, reference 4720, or the NCI supplier, reference 4412, or a polymethyl methacrylate (PMIVIA) plate, the support 1 may be a transparent film of polyester nature; we can use the reference Lumirror 60.01 in thickness 36 m or 50 m from the company Toray. For the production of the adhesive layer 2, it is advantageous to use either 40 to 55 g / m 2 of alkyl acrylate copolymers in the solvent phase of the following references: Polytex SP 2000 from AV-Chemie, Durotack 3803954 from National Starch Company, Gelva 2495 of the company ~ o Cytex. The adhesion measurements will be carried out after an accelerated aging cycle (the device bonded to the bonding substrates of the product 5 mentioned above undergoes the following climatic cycle: 16 hours at 40 ° C. and 95% relative humidity, then 3 hours at 20 ° C and then 6 hours at 85 ° C); the adhesion force at 90 ° (measured according to the AFERA 5001 method) of the support 1, 15 of the adhesive layer 2 made with one of these adhesives to the indicated weights and printing 3 on the bonding substrates of the product 5 is greater than or equal to 3 N / cm with cohesive rupture of these adhesive masses during the measurement.

Depending on the nature of the adhesive layer 2 (see the example above) the surface of the printing 3 will be adjusted on the adhesive layer so as not to degrade the adhesive performance of this layer too much. of adhesive 2 respecting the criterion indicated above. In practice, the proportion of the adhesive layer 2 covered by the printing 3 may be, for example, between 0.5% and 20% of the total area. It is preferable to print patterns with fine lines and separated from the guilloche type with a 0.2 mm width of the line, spaced apart by 2 mm, representing approximately 9% of the surface of the adhesive layer 2.

In this example, the printing 3 is carried out on a rotating coil-coil flexographic printing machine equipped in line with a delamination / re-rolling system with ultra-violet radiation drying: the stacking is unrolled support 1, adhesive layer 2, silicone protector 4 at the machine head. The support 1 and the adhesive layer 2 of the silicone protector 4 are delaminated on the delamination station. The support 1 and the adhesive layer 2 run through a circuit during which the printing plate and the ink on the surface of said plate are rolled onto the layer of adhesive 2. The ink is reflected on the layer of adhesive 2 and is dried after passing through an ultra violet radiation oven. It will be possible, for example, to use the Sigoc UFZ80114 Flexocure ink from Xsys or the Solarflex Lux Slux 46 ink from Sun Chemical. The stack of the support 1, the adhesive layer 2 and the printing 3 thus produced is re-complexed on the original silicone protector 4 which followed during this operation a parallel circuit in the printing machine.

The device according to the invention has many applications in industrial, commercial and consumer activities, and as examples, the following applications may be mentioned:

- security label for the traceability and authentication of license plates; - security label for the traceability and authentication of motor vehicles; - security label for the traceability and authentication of equipment or spare parts of motor vehicles; - security label for the traceability and authentication of industrial products; - Opening control label of any product packaging or document closure element (boxes, bottles, sachets, envelopes, etc.) The use of the device according to the invention can be extended to many areas, such as by example: aeronautics, agri-food, cosmetics, electronics, household appliances, building, DIY, health, etc.

Claims (5)

CLAIMS1- Security device for the authentication of a product (5) intended to be applied on a surface of the product (5), of the type comprising a transparent support (1) having a first face (la) and a second face (Ib), coated on its second face (lb) with a transparent layer of adhesive (2) having a first face (2a) and a second face (2b), said first face (2a) of the adhesive being contact with said second face (1b) of the support (1), and said second face (2b) of the adhesive (2) being intended to adhere to the surface of the product (5), one of said faces (2a, 2b) of the adhesive layer (2) comprising a first zone on which an impression (3) and a second zone free from said printing (3) are directly applied, said printing (3) being intended to authenticate the product (5), characterized in that said printing is provided on said second face (2b) of the adhesive layer (2), the adhesive power of the dispo said product (5) being greater than the cohesive strength of the adhesive layer (2), whereby an attempt to remove the safety device from the product (5) leads to a cohesive failure of the adhesive layer (5). adhesive (2), the distribution of the printing area within the print-free area being such that a cohesive failure of the adhesive layer leaves at least a portion of said printing (3) adhered to said product (5). 2. Device according to claim 1, characterized in that the adhesive (2) is chosen from elastomeric or acrylic pressure-sensitive adhesives, in the solvent phase, aqueous or hot-melt type. 3. Device according to any one of claims 1 or 2, characterized in that the adhesive power of the device results in a 90 ° peel force of the device on said product (5) greater than 3 N / cm. 4. Device according to any one of claims 1 to 3, characterized in that the adhesive (2) is deposited in a thickness of between 101.lm to 200 m. 5. Device according to any one of claims 1 to 4, characterized in that the thickness of the printing (3) is 1 pm to 50 m.