Security label with tamper evidence

Description

[0001] The invention relates to a security label with tamper evidence, which is constructed on a paper carrier, according to the preamble of claim 1.

[0002] Security labels with tamper evidence are known from the prior art, for example from EP 1 386 754 A, EP 2 406 074 A, EP 2 603 911 A, EP 1 972 674 A and EP 2 603 910 A, EP 2 234 091, DE 20 2012 010037 U1, EP 2 130 884 A1, AT 509 904 A2, WO 2012 / 019722 A1, WO 2012 / 019721 A1, EP 1 972 674 A1, EP 2 851 1194 A1 and WO 2005 / 075215 A2.

[0003] In general, these security labels are constructed on a carrier substrate made of a flexible plastic film and therefore have a very reliable triggering behavior.

[0004] According to the state of the art, these security labels can also be constructed on a carrier substrate consisting of paper or a composite of paper with a plastic film, but practice shows that the triggering of the tamper evidence does not work reliably with such labels.

[0005] However, there is a demand for security labels with tamper evidence that are made of paper and therefore exhibit the typical paper behavior, for example the typical tearing under mechanical stress.

[0006] If a composite of paper with a plastic film is used as the carrier substrate, these typical paper properties are completely lost.

[0007] In addition, the composite can usually be separated more or less easily, so that such a security label is only partially secure against tampering.

[0008] The object of the invention was therefore to provide a security label with tamper evidence, which is constructed on a paper substrate, has the typical paper behavior and also allows a reliable triggering of the tamper evidence.

[0009] The invention therefore relates to a security label with tamper evidence, according to claim 1.

[0010] The invention is based on the finding that the release lacquer layer applied to the surface of the paper according to the known prior art or a functional layer, such as a colored lacquer layer or a metallic layer, penetrates into the paper and thus hinders the clear triggering of the tamper evidence.

[0011] The paper substrate consists of pulp-free or pulp-containing paper, with a basis weight of 20–500 g / m2, preferably 40–200 g / m2. Optionally, the paper may also contain a proportion of plastic fibers.

[0012] According to the invention, the surface of the paper substrate is now sealed by means of a priming lacquer layer, whereby this priming lacquer layer does not penetrate into the paper, but only seals the surface and thus prevents the penetration of the release lacquer layer or a functional layer into the paper.

[0013] The release coating and / or the functional layer thus remains on the surface of the priming coating layer, thus ensuring that the tamper evidence can be triggered without any problems.

[0014] The priming lacquer layer can be applied as a printed layer by means of a printing process such as gravure printing, flexographic printing, screen printing and the like, by roller application processes such as smooth roller processes or by brushing or spraying onto the paper surface.

[0015] Preferably, such a lacquer layer is provided on a substrate made of a flexible plastic film, for example a polyester film, and then transferred or sealed to the paper substrate, optionally using an adhesive layer, for example a laminating adhesive layer or a hot-melt adhesive layer, under the influence of pressure and / or temperature. The plastic film is then peeled off.

[0016] The paper substrate treated in this way is then provided with a structure on the surface carrying the primer layer of paint that allows detection of tampering.

[0017] For this purpose, a partial release coating is applied in a first step. Particularly suitable release coatings are known, poorly adhering coating compositions, for example, those based on cycloolefin copolymers, nitrocellulose, acrylates, polyvinyl chloride, ethylene acrylate copolymers, or styrene acrylates in a suitable solvent. Chlorinated polyolefins are preferably added to adjust the adhesion. The proportion of chlorinated polyolefins in the composition can be 1-50 wt.%, preferably 1-25 wt.%, particularly preferably 1 to 15 wt.%, relative to the base polymer.

[0018] Furthermore, very thinly applied polyamide, polyethylene, fluoropolymer wax layers or silicone coatings can also be used as a release layer.

[0019] The release coating may be applied in the form of a pattern, in the form of symbols, letters, numbers, images, patterns, logos, lines, guilloches, texts, lettering or the like.

[0020] Depending on requirements, the adhesion of the partial release coating layer can be adjusted in such a way that the adhesion of the release coating layer to the priming coating layer is greater than the adhesion to the layer subsequently applied to this release coating layer.

[0021] Alternatively, the adhesion of the release coating layer can be adjusted such that the adhesion of the release coating layer to the layer subsequently applied to the release coating layer is higher than the adhesion to the priming coating layer.

[0022] By adjusting these adhesion conditions, it is ensured that in the event of manipulation, separation occurs at one of the boundary layers of the release coating.

[0023] A functional layer is then applied to this partial release coating. A functional layer is defined as a layer that can have security features, for example, optical security features such as a defined color, or optically variable properties or reflective properties.

[0024] This layer can be, for example, a printed layer or a metallic layer. A printed layer has an optical security feature and is preferably colored, white, or black. The optical properties of this layer can be customized using visible dyes or pigments, luminescent dyes or pigments that fluoresce or phosphoresce in the visible, UV, or IR ranges, effect pigments such as liquid crystals, pearlescent pigments, metallic pigments, bronzes, and / or multilayer color-change pigments, and heat-sensitive dyes or pigments.

[0025] Particularly preferably, such a printing layer is designed in a color that contrasts with the color of the paper substrate.

[0026] A metallic layer can be applied, for example, by depositing metals or metal compounds or alloys using PVD or CVD processes.

[0027] Examples of suitable metals are Al, Sn, Cu, Zn, Pt, Au, Ag, Cr, Ti, Mo, Fe or their alloys, such as Cu-Al, Cu-Sn, Cu-Zn, iron alloys, steel, stainless steel or the like, and examples of suitable metal compounds are stoichiometric or non-stoichiometric oxides or sulfides.

[0028] The metallic layer can be made at least partially reflective.

[0029] A reflective metallic layer may optionally be combined with an optically active structure, for example with a diffraction structure, a surface relief, a diffraction grating, a hologram or a kinegram and the like.

[0030] The paper substrate may be provided with further security features on the surface opposite the primer layer, for example with full-surface or partial printing, optically active or optically variable security features, conductive or magnetic coatings and the like.

[0031] Furthermore, the paper substrate itself can have security features, such as fluorescent fibers, dots, planchettes, etc. The security label is then attached to the material to be secured using an adhesive layer, such as a self-adhesive coating.

[0032] Object is fixed, whereby the self-adhesive coating is situated on the functional layer.

[0033] If tampering is attempted, for example, by peeling, scraping, or the like, the functional layer will separate from the primer coating in the area where the release coating is applied. Depending on the adhesion conditions, the release coating may remain on the primer coating or on the functional layer.

[0034] In any case, on the peeled-off paper substrate with the primer layer, the patterns, symbols, letters, numbers, images, lines, guilloches, texts, lettering, logos and the like resulting from the formation of the release layer are recognizable in the form of a negative of the printed release varnish; on the part of the label that remains on the object to be secured, these patterns, symbols, letters, numbers, images, lines, guilloches, texts, lettering, logos and the like appear in the form of a positive of the printed release varnish.

[0035] The security label according to the invention can be used in any shape (round, square, oval) to secure objects, products, packaging, as a seal and the like.

[0036] In the Figures 1 to 5 Embodiments of the security label according to the invention are shown: In this,

[0037] 1 the paper substrate 2 the priming lacquer layer 3 the partial release lacquer layer 4 the functional layer (with security features) 5 a plastic film 6 a laminating adhesive layer 7 a self-adhesive layer 8 the object to be secured 9 a further security feature 10 area of ​​the release lacquer layer 11 area of ​​the functional layer 12 the paper surface 13 the smooth surface 14 the surface of the paper substrate opposite the priming lacquer layer 15 the security label according to the invention 16 the part of the label that is removed with the paper substrate 17 the part of the label that remains on the object to be secured 8 18 the part of the functional layer that remains on the object and has patterns, symbols, letters, numbers, images, lines, guilloches, texts, lettering, logos and the like in the form of a positive of the printed release lacquer 19 the part of the functional layer,which remains on the peeled-off part of the label and has patterns, symbols, letters, numbers, images, lines, guilloches, texts, lettering, logos and the like in the form of a negative of the printed release liner.

[0038] In Figure 1 An embodiment according to the prior art is shown. A partial release coating 3 and subsequently a functional layer 4 are applied to the paper substrate 1.

[0039] Due to the roughness of the paper surface 12 and the porosity of the paper substrate, the release coating layer 3 and possibly also partially the functional layer 4 sinks completely or partially into the paper substrate 1 in the areas 10 and in the areas 11 not coated with the release coating layer 3, the functional layer 4 sinks completely or partially into the paper substrate 1.

[0040] This prevents reliable triggering of the tamper evidence, as no smooth separation of the layers from each other or from the paper substrate is possible.

[0041] In Figure 2 An embodiment of the invention is shown in which the paper substrate 1 is provided with a primer layer 2 applied by a printing process. This creates a smooth surface 13.

[0042] A partial release layer 3 and then a functional layer 4 are applied to this primer layer 2.

[0043] On the surface 14 of the paper substrate 1 opposite the priming lacquer layer 2, a further security feature 9 is applied in the form of a partial layer, for example a print.

[0044] The label is attached to the object 8 to be secured by means of a self-adhesive coating 7.

[0045] In case of an attempt at manipulation ( Fig. 2a ) the functional layer 4 partially separates from the priming lacquer layer 2 in the areas 10, whereby the release lacquer layer 3 can remain on the priming lacquer layer 2 or on the functional layer 4 depending on the adhesion conditions.

[0046] In the areas 11, the adhesion of the individual layers 2 and 4 to each other is so high that either the adhesive coating 7 is peeled off the object to be secured or, as in Fig. 2a shown, the functional layer 4 is peeled off the adhesive layer 7.

[0047] The inventive embodiment of the priming lacquer layer 2, which does not sink into the paper substrate 1 but seals it, ensures a clean separation of the layers.

[0048] The patterns, symbols, letters, numbers, images, lines, guilloches, texts, lettering, logos and the like caused by the formation of the release lacquer layer 3 in the areas 10 are recognizable on the peeled-off paper substrate 1 with the priming lacquer layer 2 in the form of a negative of the printed release lacquer 3, on the part of the label that remains on the object to be secured, these patterns, symbols, letters, numbers, images, lines, guilloches, texts, lettering, logos and the like appear in the form of a positive of the printed release lacquer in the areas 11, as in Figure 2a is shown. Here, the release coating layer 3 remains on the priming coating layer 2, since in this example the adhesion of the release coating layer 3 to the priming coating layer 2 is greater than to the functional layer 4.

[0049] Alternatively, depending on the adhesion conditions set, the release coating layer 3 can also remain on the functional layer 4, in which case the adhesion of the release coating layer 3 to the priming coating layer 2 is lower than the adhesion of the release coating layer 3 to the functional layer 4.

[0050] The appropriate adhesion conditions are adjusted by adding suitable additives, for example chlorinated polyolefins, in the appropriate amount to the base polymer.

[0051] In the Figures 3a and 3b an embodiment is shown in which the paper substrate 1 is provided with a primer lacquer layer 2 which was applied by means of a transfer process.

[0052] Figure 3a shows the structure of the base material, Figure 3b the structure of the finished security label.

[0053] For the base material, Figure 3aa priming lacquer layer 2 formed on a plastic film 5 is transferred onto the paper substrate 1, which is anchored to the surface 12 of the paper substrate 1 by means of a laminating adhesive layer 6.

[0054] Then the plastic film 5 is removed and, as in Figure 3b shown, the partial release coating layer 3 and then the functional layer 4 are applied.

[0055] This setup shows the same triggering behavior in case of a manipulation attempt as the one in the Figures 2 illustrated and described embodiments.

[0056] In Figure 4 a security label 15 according to the invention with a print is shown in plan view.

[0057] Figure 5 shows this security label 15 after attempting to peel it off.

[0058] Part 17, which remains on the object to be secured, shows letters or the word "VOID" in the form of a positive of the printed release varnish.

[0059] Part 16, which is peeled off with paper substrate, shows letters or the word "VOID" in the form of a negative of the printed release liner. Examples: Example 1: priming print layer 1

[0060] NeoRez R 600 23.1 kg BYK 016 0.011 kg Crosslinker CX 100 0.7 kg Water 1,2 l

[0061] The primer printing layer is applied to the paper surface using a smooth roller process. Example 2: priming print layer 2

[0062] Alberdingk APU 10610 VP 51.2 kg Hardener Baydur 3100 1.5 kg Water 9.35 kg

[0063] The priming printing layer is applied to the paper surface using a gravure printing process. Example 3: primer transfer varnish layer 1 (almost the original recipe, please modify.)

[0064] Ebecryl 108 6.9 kg Ebecryl TMPTA 7.8 kg Ebecryl 83 10.0 kg Ebecryl 5129 10.17 kg Irgacure 819 1.88 kg

[0065] The lacquer layer is produced on a flexible plastic film made of PET and then laminated onto the paper substrate using a laminating adhesive under the influence of pressure and temperature. Example 4: primer transfer varnish layer 2

[0066] Michem ®< Flex HS-100 The lacquer layer is produced on a flexible plastic film made of PET and then sealed onto the paper substrate under the influence of pressure and temperature.

Claims

1. A security label with tamper evidence, comprising a carrier substrate, a partial separating lacquer layer and a functional layer, wherein the functional layer is located on the partial separating lacquer layer, characterized in that the carrier substrate is a paper substrate which is provided with a priming lacquer layer which seals the surface of the paper substrate, and in the event that the paper substrate has a Bendtsen roughness according to ISO 8791-2 of < 50 ml / min and a Bendtsen porosity according to ISO 5636-3 of < 70 ml / min, the priming lacquer layer is based on a 2-component polyurethane dispersion or an acrylate / polyurethane hybrid dispersion or on radiation-curable, in particular UV-curable lacquers based on acrylic methacrylates, such as trimethylolpropylene triacrylate, hydroxyethyl methacrylate, acrylic epoxy resins, polyfunctional aliphatic urethane acrylates or amine-modified polyfunctional polyethyl ether copolymers or mixtures thereof, to which one or more photoinitiators are added for crosslinking, and in the event that the paper substrate has a Bendtsen roughness according to ISO 8791-2 of > 50 ml / min and a Bendtsen porosity according to ISO 5636-3 of > 70 ml / min, the priming lacquer layer is based on radiation-curable, in particular UV-curable lacquers based on acrylic methacrylates, such as trimethylolpropylene triacrylate, hydroxyethyl methacrylate, acrylic epoxy resins, polyfunctional aliphatic urethane acrylates or amine-modified polyfunctional polyethyl ether copolymers or mixtures thereof, to which one or more photoinitiators are added for crosslinking, wherein the partial separating lacquer layer is applied to the priming lacquer layer and the security label is provided with a self-adhesive coating on the functional layer.

2. The security label according to claim 1, characterized in that the priming lacquer layer is formed by a printed layer.

3. The security label according to claim 1, characterized in that the priming lacquer layer is a transfer lacquer layer.

4. The security label according to one of claims 1 to 3, characterized in that the functional layer has a security feature.

5. The security label according to claim 4, characterized in that the security feature of the functional layer is an optical security feature.

6. The security label according to one of claims 1 to 5, characterized in that the functional layer is configured as a printed layer, as a metallic layer and / or as an optically active layer.

7. The security label according to one of claims 1 to 6, characterized in that the paper substrate itself has security features or is provided with a security feature on the surface opposite the priming lacquer layer.

8. A use of the security label according to one of claims 1 to 7 for securing objects, products, packaging or as a seal.