AT509904A2 - SAFETY LABEL WITH MANIPULATION DETECTION - Google Patents

Description

10/06 2010 THU 18: 08 FAX 43 7235 63933 14 0004/023 10/06 2010 THU 18: 08 FAX 43 7235 63933 14 0004/023

Security label with proof of tampering

The invention relates to a security tag with proof of manipulation, which contains an optically active security feature and an RFID antenna as well as an optically detectable tamper evident.

An optically active feature is understood here to mean diffraction structures, diffraction gratings, surface reliefs, holograms, kinegrams and the like. 10

From WO 2008/067830 a tamper-proof RFID antenna structure comprising a carrier substrate, an RFID antenna, optionally a chip, and a Kiebebeschichtung, known, wherein on the carrier substrate in the region of the RFID antenna partially a release layer is applied and the entire structure full-surface or partially (with the exception of the contact points for the chip) is provided with a lacquer which has sufficient adhesion to the antenna material and the carrier substrate and a good anchorage to the adhesive layer applied to this lacquer layer.

In a tampering attempt, the antenna is destroyed and thus loses its functionality.

From WO 2010/028777 a manipulation-secure RFID antenna with security feature is known, comprising a carrier substrate, a thin UV-curable lacquer layer in which a hologram is embossed, a partial metallization as a mirror layer, optionally a smoothing lacquer layer, possibly a partial Copper layer that forms the antenna, if necessary, a strap or microchip, a Kiebebeschichtung, possibly a release liner and possibly other layers. The RFID antenna can be attached to a substrate by means of the sliding coating and, in addition to the RFID antenna, has a security feature in the form of a hologram. If, in the event of a manipulation, the carrier substrate is removed again, the antenna remains on the object to be secured and a detachment of the remaining structure from the object is due to 10/06 2010 DO 18:07 LSE / EM NR 7591] ®004 .0 / 06 2010 DO 18:08 FAX 43 7235 63933 14 0005/023

small overall thickness is no longer possible. However, a clearly recognizable optical manipulation proof is not provided.

The object of the invention was therefore to provide a structure for a security label with 5 proof of tampering, comprising an optically active security feature and an RFID functionality, wherein the antenna is not destroyed when triggering the tamper evidence and the RFID part of the label after manipulation yet is functional. The invention therefore relates to a security label with tamper evidence comprising an at least partially transparent flexible carrier substrate based on a flexible plastic film, characterized in that the following layers are applied to a surface of the carrier substrate: a) an embossed lacquer layer b) a semitransparent or reflective metal layer or a transparent layer having a high refractive index c) a partial release lacquer layer in the form of letters, characters, symbols, lines, guilloches, numbers or lettering, d) a full-surface lacquer layer e) an RFID antenna f) an RFID chip g) a self-adhesive coating, wherein in the not coated with the release lacquer layer c) areas 25) layer b) worse on the layer a) adheres than all other layers and the adhesion of the layer b) to the layer a) is less than the adhesive force of the self-adhesive coating on the object and in the with the doors nlackschicht c) coated areas, the layer c) worse on the layer b) or d) is liable than all other layers with each other and the adhesion of the layer c) to the layer b) or d) is less than the bond strength of the self-adhesive coating on the object. 10/06 2010 THU 18:07 [SE / EM NO. 7591] 0OO5 .0 / 06 2010 THU 10:08 FAX 43 7235 63933 14 @ 006/023

3

For example, carrier foils are preferably flexible plastic foils, for example, PI, PP, MOPP, PE, PPS, PEEK, PEK, PEI, PSU, PAEK, LCP, PEN, PBT, PET, PA, PC, COC, POM, ABS, PVC , Fluoropolymers such as Teflon and the like in question. The carrier films preferably have a thickness of 5 to 700 μm, preferably 5 to 200 μm, particularly preferably 5 to 100 μm, and are preferably at least partially transparent for wavelengths in the visible range of the light. The carrier film can appear completely transparent in the visible region and thus reproduce the optically active feature underneath it, as seen by the observer. However, the support film may be colored, for example, translucent, so that overlay the color of the film with the properties of the optically active feature. Thus, in a simple manner, e.g. a red hologram can be made. If appropriate, an adhesion promoter layer can be applied to the carrier substrate, which improves the adhesion of the subsequently applied lacquer layer a) to the carrier substrate. Alternatively, a corresponding chemically or physically pretreated carrier substrate can be used.

However, the lacquer layer a) can also be applied directly to the carrier substrate if the lacquer has sufficient adhesion to the carrier substrate without further measures.

In any case, the adhesion of the lacquer layer a) to the carrier substrate must be adjusted so that neither when removing the security label from a release liner nor when triggering the tampering, does the lacquer layer a) detach from the carrier substrate.

The lacquer layer a) has a surface structure on the surface facing away from the carrier substrate, for example a surface relief, a hologram, a diffraction structure or a diffraction grating. This structure 30 can be produced by means of known hot embossing or UV embossing processes by molding structures present on an embossing tool. When using a hot embossing process, the lacquer layer is a) 10/06 2010 DO 18:07 [SE / EM NO 7591] @ 006/06 2010 DO 18:09 FAX 43 7235 63933 14 12) 007/023 / 06 2010 DO 18: 09 FAX 43 7235 63933 14 12) 007/023

thermoplastic lacquer layer, when using a UV embossing process is the lacquer layer a) radiation-curing. Such embossing methods are well known to those skilled in the art, or disclosed in EP-A 1 310 381, the contents of which are incorporated in the present application in full volume.

The layer thickness of the lacquer layer a) can vary depending on the requirements of the end product and thickness of the substrate and is generally between 0.5 and 50 .mu.m, preferably between 2 and 10 .mu.m, particularly preferably between 2 and 5 μίτι.

Subsequently, a semitransparent or reflective metallic layer or a transparent layer with a high refractive index b) is applied to the lacquer layer a) in order to obtain an at least partial reflection of incident light at the embossed interface between lacquer layer a) and layer b) to make the optically active feature visible to the viewer.

As metallic layers, for example, layers of a metal, 20 or an alloy in question. As the metal layer, layers of Al, Cu, Fe, Ag, Au, Cr, Ni, Zn, Sn, Pt, Ti, Pd and the like are suitable. Suitable alloys are, for example, Cu-Al alloys, Cu-Zn alloys and the like.

The metallic layer may preferably be applied by a PVD or CVD process 25 (sputtering, vapor deposition, vapor deposition).

The thickness of the metallic layer is 1 to 200 nm, preferably 20 to 60 nm. A fully reflective layer is obtained if its optical density is greater than about 1.7, usually optical densities of 2.0 to 30 2.5 are set , A semitransparent metal layer is obtained if the optical density is less than 1.4 OD, the degree of transparency can be adjusted by the residual absorption of the layer and with 10/06 2010 DO 18:07 [SE / EM NO 7591J © 007, 0/06 2010 DO 18:09 FAX 43 7235 63933 14 0008/023, 0/06 2010 DO 18:09 FAX 43 7235 63933 14 0008/023

increasing layer thickness {= increasing optical density) decreases. If the optical density of the metallic layer is less than 0.5, the underlying layers are still clearly visible in color and structure. Alternatively, inks containing platelet-shaped metal pigments and having the property of attaching the metal pigments to the embossed surface may be used. Platelet-shaped in this case means that the thickness is significantly less than the lateral extent of the pigments. 10

Alternatively, the layer b) can be designed as an HRI layer. This HRI layer may preferably consist of a lacquer layer with a high refractive index, or of a layer of metal compounds. Suitable metal compounds are, for example, oxides or sulfides of metals, in particular TiO 2, Cr oxides, ZnS, Cu oxides, indium tin oxide, antimony tin oxide, antimony zinc oxide, fluorine tin oxide, ZnO, Al 2 O 3 or silicon oxides.

High refractive index lacquer layers are preferably applied by known printing methods, layers of metal compounds are preferably applied by a PVD or CVD process (sputtering, vapor deposition, vapor deposition).

Subsequently, a release coating c) partially, for example in the form of letters, characters, symbols, lines, guilloches, numbers or 25 inscriptions applied.

As a release varnish c) are preferably known, poorly adhering coating compositions, for example based on Cylclooiefincopolymeren, nitrocellulose, acrylates, polyvinyl chloride, 30 ethylene acrylate copolymers or styrene acrylates in a suitable solvent in question. For precise adjustment of the adhesion, preferably chlorinated polyolefins are added. The proportion of chlorinated 10% 2010 DO 18:07 [SE / EM NR 7591] @ 008 LO / 06 20 10 DO 18:09 FAX < 13 7235 63933 14 0009/023 I # · · · t · * # * · · «» »♦ *« · · · · · * * * «« «« f 6

Polyolefins in the composition can be 0 to 130% by weight relative to the base polymer.

Alternatively, any coating systems whose adhesion is reduced by an additive, for example Byk 394®, can be used. Furthermore, very thinly applied polyamide, polyethylene, fluoropolymer wax layers or silicone coatings can also be used. Optionally, the release lacquer layer may be provided with security pigments such as fluorescent pigments and the like. 10 The adhesion of the release lacquer layer c) is adjusted so that upon release of the tamper evidence the release lacquer coating c) either from the layer b) or the layer d) dissolves, the remaining film structure is retained in its structure. In any case, the adhesion of the release lacquer layer c) is less than the adhesion of the semitransparent or reflective metallic layer b) to the embossing lacquer layer a).

The separating lacquer layer c) is partially applied by a printing process, for example by gravure, flexo, offset, screen or digital printing. The layer structure with the release lacquer layer c) is now coated with another lacquer layer d), which can have an arbitrary lacquer composition. The lacquer layer d) can contain dissolved dyes or color pigments, pearlescent or effect pigments and contain invisible features in the visible spectral range, such as UV- or IR-fluorescent, phosphorescent, thermochromic, photochromic additives or pigments.

The thickness of the lacquer layer d) is adjusted so that the surface irregularities which result, on the one hand, from the embossing in the embossing lacquer layer a) and, on the other hand, from the partially applied lacquer layer c), are compensated again for the further layers Surface is available. The thickness is 1-50 pm, preferably 3-10 pm. 10/06 2010 DO 18:07 [SE / EM NR 7591] @ 009 - Ο / 0 S 2010 DO 18:09 FAX 43 7235 63933 14 0010/023 - Ο / 0 S 2010 THU 18:09 FAX 43 7235 63933 14 0010/023 • · · · · ·

«T« ♦ ··· «······« «

The lacquer layer d) is applied by a coating method such as spraying, casting, painting, anilox roller coating, curtain coating, slot die coating, dipping or the like, or with one of the printing methods used to apply the layer c).

The above structure consisting of the carrier substrate and the layers a) to d) represents the optical or optically active part of the security label. This is now combined with an RFID part, which in turn consists of an RFID antenna e) and an RFID Chip f).

The RFID antenna e) can be made by methods known to those skilled in the art, e.g. by coiling a thin wire, by printing a conductive ink, by laminating a 15 etched, cut or stamped metal foil or, in a preferred embodiment, by partially applying a metallic coating.

In the preferred embodiment, the RFID antenna e) consists of a partial metallic coating. Suitable metallic coatings are 20 highly conductive metals, preferably Cu, but also Au, Ag, or Sn. The metallic coating is vapor-deposited by means of a PVD or CVD process in one or more individual layers and then patterned by an etching process or a washing process. Such methods are described for example in EP-A 1 332 238. 25

The antenna is now connected to an RFID chip or module f), either directly by means of a conductive adhesive or solder connection or via an inductive or capacitive coupling. In the latter case, usually not only the chip is applied to the antenna, but a module which consists of the chip itself and a small antenna, which is then glued and uses the larger antenna on the label as an amplifier. The exact embodiment 10/06 2010 DO 18:07 [SE / EM NO 7501J 0010 .0 / 06 2010 DO 18:09 FAX 43 7235 63933 14 0011/023 .0 / 06 2010 DO 18:09 FAX 43 7235 63933 14 0011 / 023 * * m · »8" depends on the application and desired characteristics, such as reading range and operating frequency.

Finally, a self-adhesive coating g) is applied to the entire structure over its entire surface, with the aid of which the label can be anchored on an object to be secured. In any case, the adhesive strength of the carcass coating g) must be high enough to allow the proof of tampering to be triggered without detaching the entire label from the object. Depending on the application, the thickness of the SK coating is 10 1 - 100 pm.

For simplified handling of the security label this is applied to a so-called release liner, which is usually made of a siliconized paper or a siliconized film, and isolated by punching 15 or cutting. However, this step is application specific and does not need to be done.

On the side of the security label which is opposite the above layer structure, it is optionally also possible to apply a printing primer, which gives good printability and good adhesion of a possibly applied printing layer.

The label may additionally be provided with a graphic or security print 25 on the side of the carrier substrate facing the viewer in order to convey further information to the user.

If the label is affixed to an object to be secured, the visually active security feature is first of all for the viewer! and possibly a print on 30 visible. In a manipulation attempt, the carrier film can be peeled off and in the areas not coated with the release lacquer layer c) the metallic or HRI layer b) separates from the embossing lacquer layer a) and 10/06 2010 DO 18:07 iSE / EM NTR 7501] 0011. 0/06 2010 DO 18:09 FAX 43 7235 63933 14 0012/023

thus remains with further layers (d) - f)) on the object to be secured. However, in the areas coated with the release lacquer layer, the release lacquer layer c) separates either from the layer b) or the layer d), since the release lacquer layer c) locally modifies the adhesions. The regions of the metallic or HRI layer b), which are coated with release lacquer in the original structure, thus remain on the embossing lacquer layer a) and are removed with the carrier substrate. If the separating lacquer layer c) is printed in the form of characters, the metallic or HRI layer remains in the form of negative signs on the object and in the form of positive marks on the carrier substrate. Regardless of the exact geometric shape of the release lacquer layer c), the above-mentioned positive-negative effect is always produced during separation.

The self-adhesive coating f),] 5 the lacquer layer d) and parts of the layer b) remain on the object to be secured. The self-adhesive coating f) is covered over the entire surface of the paint layer d), so that the residue for the user is no longer sticky. This is termed the "dry peel effect". designated. On the one hand, this does not impair the handling of the object, on the other hand it makes it impossible to anchor the withdrawn carrier substrate 20 back onto the object and to render the manipulation attempt unrecognizable.

The tamper evidence of this security label can also be used deliberately to visually "devaluate" the label. For example, if the security tag is glued to a consumer good that is being sold in a department store, the seller may visually "devalue" the tag, and it may be seen, for example, that the merchandise has been paid. For this purpose, e.g. the release varnish layer c) in the form of the text "PAID " printed. However, the RFID part is still functional and can be read by machine when it is taken back for 30 service purposes or, in the event of a complaint. The optically active security feature, which also applies after removal of the 10/06 2010 DO 18:07 ISE / EM NR 7581] © 012 .0 / 06 2010 DO ΙβιΙΟ FAX 43 7235 63933 14 0013/023 * 1 * · 4 • I · · * * I * * * * • 4 * * * 4 * 9 «*» t »9 4 *

Carrier substrate is still recognizable, as evidence of authenticity for the user is also maintained.

The invention will be explained in more detail with reference to Figures 1 to 6. 5

Figures denote the reference numerals; the security tag according to the invention the optically active security feature the print in the form of a readable text the RFID antenna the RFID chip the visible sign after subtracting the carrier substrate in the form of a negative text which remains on the object to be secured the visible sign after removal of the carrier substrate in the form of a positive text which is peeled off with the carrier substrate the carrier substrate with functional layers a printing primer the primer layer the embossed lacquer layer the reflective metallic or HRI layer the partial release lacquer layer in the form of characters the colored or transparent lacquer layer the adhesive coating that through the security label protected substrate In the 1 2 3 10 4 5 6 7 15 8 9 10 11 20 12 13 14 15 16 25th

Fig. 1 shows a security label 1 according to the invention in the initial state, that is, after it has been applied to an object to be secured. In this state, on the one hand, the optically active feature 2 and on the other hand, a pressure applied to the surface of the label 3 visible.

Fig. 2 shows a view of the security label 1 of the invention from the back, before the label is adhered. In this version 9form is 10/06 2010 DO 16:07 [SE / EM NR 7501] @ 013 30 .0 / 06 20 1 0 DO L8: 10 FAX 43 7235 63933 14 0014/023 ΊΊ also the optically active characteristic 2 is visible as well in addition, the RFID antenna 4 and the RFID chip 5. These two components together form a resonant circuit, which has the consequence that upon excitation by an external magnetic field data from and to the chip can be transmitted. The chip 5 can be coupled to the antenna in several ways: There may be a direct conductive contact between the antenna and the chip, e.g. through a conductive adhesive or a solder joint. The two components can also be coupled contactless capacitive or inductive. Fig. 3 shows the state of the security label 1 glued to an object to be secured in an attempt to detach it. The RFID antenna 4 and the RFID chip 5 remain on the substrate and are still fully functional. By peeling off the carrier substrate 8, a further, clearly visible sign in the form of the text "VOID" appears, which is recognizable as negative text 6 in the layer structure remaining on the object and as positive text 7 on the carrier substrate. The applied pressure on the surface of the label 3 is withdrawn with the carrier substrate.

Fig. 4 shows the state of the security label 1 when the carrier substrate 8 20 is completely peeled off. Only a part of the optically active security feature 2 and the negative text 6 can be recognized. However, the RFID function of the label is completely intact. The part that remains on the object to be secured is no longer sticky because the adhesive layer is completely covered by further layers. 25

Fig. 5 shows the security label 1 in cross section. On the one side of the carrier substrate 8, an (optional) pressure primer 9 is applied. This has the function that the pressure 3 adheres better to the carrier substrate and the print quality is better than on the carrier substrate itself, the carrier substrate 30 itself, however, can already be such that a sufficient printability is given, whereby the printing primer 9 can be omitted. On the opposite surface of the carrier substrate 8 is another 10/06 2010 DO 18:07 [SE / EM NR 7581] @ 014/06 2010 DO 18:10 FAX 43 7235 53933 14 0015/023 / 06 2010 DO 18:10 FAX 43 7235 53933 14 0015/023

The adhesion promoter layer ensures that the embossing lacquer layer adheres well to the carrier substrate and can be omitted if the adhesion of the embossing lacquer layer 11 to the carrier substrate 8 is sufficient without further measures, or if the Carrier substrate 8 is already pretreated physically or chemically. The embossing lacquer layer 11 is provided with an embossing on its side facing away from the carrier substrate 8. On this embossed surface, a semitransparent or reflective metallic layer or a transparent layer with a high refractive index 10 12 is applied. In Fig. 5 this is shown over the entire surface, but this is not absolutely necessary. Subsequently, a partial release lacquer layer 13 is printed in the form of characters. These signs appear in the case of a

Manipulation attempt on the detached or remaining on the object substrate as a positive or negative (see 6, 9 in Fig. 1-4). Thereafter, the entire label 15 is coated over its entire surface with a lacquer layer 14. Further, an RFID antenna 4 and an RFID chip 5 are applied to the above structure. Finally, the entire label is still provided with a sliding coating 15 which is suitable for fixing the label on an object 16, 20

Fig. 6 shows now in cross-section the state of the security label 1 in an attempt to manipulate analogous to FIG. 3. In the coated with release coating 13 areas of the release coating 13 dissolves from the underlying lacquer layer 14. In the other areas, however, solves the 25th Metalichichi 12 of the embossing lacquer layer 11. As a result, a part of the metallic black 12 remains on the object to be secured 16 and the remaining part is peeled off with the carrier substrate 8. The part of the label assembly that remains on the object 16 is so thick at all points that the adhesive coating is completely covered. Thus, the surface of the residue on the object is no longer sticky (dry peel effect).

The following examples show film constructions with which a security label according to the invention can be produced. 10/06 2010 DO 18:07 [SE / EM NO 7591] 0015 0/06 20 L 0 DO 18i 10 FAX 43 7235 63933 14 0016/023

Example 1:

Digital printing partially with text "Security Label"

Digital printing primer, 1.5 g / m2 PET film highly transparent, 36 μm, chemically pretreated on both sides 5 UV-curing embossing lacquer, 3 g / m2 with hologram embossing Al metallization, 35 nm

Transparent release varnish layer partially printed {Text "VOID") based on a cycloolefin copolymer with a content of 50% chlorinated polyolefins, 0.5 g / m2 10 Full-surface transparent, crosslinked polyester-based varnish layer, 5 g / m2 Partial Cu metallisation, 1 , 5 pm thick in the form of an RFID antenna RFID chip, with adhesive adhesive bonded to the antenna Self-adhesive coating, 15 g / m2 release liner 15

Example 2: PET film, 36 μm, translucent red colored adhesion promoter layer, 0.5 g / m2 hot stamping lacquer, 4 g / m 2 with hologram embossing 20 Al metallization, 20 nm

Transparent release varnish layer partially printed (check pattern) based on a fluoropolymer, 0.5 g / m2

Voilflächige lacquer layer based on nitrocellulose, 3 g / m2 laminating adhesive, 3 g / m2 25 RFID antenna based on a stamped Al foil (20 pm thick) RFID chip, with conductive adhesive connected to the antenna

Self-adhesive coating, 15 g / m2

Release-liner 10/06 2010 D0 18:07 [SE / EM NR 75B1J ®016

Claims (13)

1. Security label with tamper evidence comprising an at least partially transparent flexible carrier substrate based on a flexible plastic film, characterized in that the following layers are applied to a surface of the carrier substrate: a) an embossed Lacquer layer b) a semitransparent or reflective metal layer or a transparent layer with a high refractive index c) a partial release lacquer layer in the form of letters, characters, symbols, lines, lines, numbers or lettering, d) a full-surface lacquer layer e) an RFID antenna f g) a self-adhesive coating, wherein in the areas not coated with the release lacquer layer c) the layer b) adheres worse to the layer a) than all other layers and the adhesion of the layer b) to the layer a) is lower as the adhesive power of the self-adhesive coating on the obje kt and in the regions coated with the release lacquer layer c) the layer c) adheres worse to the layer b) or d) than all other layers and the adhesion of the layer c) to the layer b) or d) is less than the bond strength of the Self-adhesive coating on the object. 2. Security label according to claim 1, characterized in that between the carrier substrate and the embossed lacquer layer a) a bonding agent layer is provided. 3. Security label according to one of the preceding claims, characterized in that on the embossing lacquer a) opposite surface of the carrier substrate, a pressure primer is provided. 10/06 2010 DO 18:07 [SE / EM NR 7591] 0017 15/06 2010 DO 18:10 FAX 43 7235 63933 14 0018/023 4. Security label according to one of the preceding claims, characterized in that the security label is printed. 5. Security label according to one of claims 1 to 4, characterized 5, characterized in that the RFID antenna e) is formed by partial application of a metallic layer. 6. Security label according to one of claims 1 to 4, characterized in that the RFID antenna e) is formed by a punched, 10 etched or cut Metalllfolie, which is anchored by means of an adhesive layer on the lacquer layer d). 7. Security label according to one of claims 1 to 4, characterized in that the RFID antenna e) is formed by a conductive printing layer 15. 8. Security tag according to one of claims 1 to 7, characterized in that the RFID chip f) is connected by means of a conductive adhesive to the antenna. 20 9. Security tag according to one of claims 1 to 7, characterized in that the RFID chip f) is inductively or capacitively coupled to the antenna e). 10. Security label according to one of the preceding claims, characterized in that the embossing of the lacquer layer a) represents an optically active structure in the form of a diffraction structure, a diffraction grating, surface relief, hologram or Kinegram. 11. Security label according to one of the preceding claims, characterized in that after the triggering of the tamper evidence 10/06 2010 DO 18:07 [SE / EH NR 75911 @ 018 10/06 2010 DO 18:10 FAX 43 7235 63933 14 0019/023 10/06 2010 THU 18:10 FAX 43 7235 63933 14 0019/023 • ♦ • I · • * * '. On the object structures in negative form and on the carrier substrate in positive form or vice versa become visible. 12. Security tag according to one of the preceding claims, characterized 5, that after the triggering of the tamper evidence of the RFID part of the label is still functional. 13. Security label according to one of the preceding claims, characterized in that after the triggering of the tamper evidence 10 of the object remaining on the part of the security label is no longer sticky. 10/06 2010 DO 18:07 [SE / EM NO 7591] 0019