EP1451791B1 - Label with improved anti-forgery security - Google Patents

Description

The invention relates to a label with increased Fälschungssichefieit of a paint layer, in particular of thermosetting paint for laser marking.

For identification of parts of vehicles, machinery, electrical and electronic devices are increasingly used technical labels, such as nameplates, as control labels for process flows as well as warranty and inspection labels.

In many cases, these applications inherently involve the requirement for a more or less pronounced level of counterfeiting. This counterfeiting security applies ostensibly for the period of attachment and the entire useful life on the part to be marked. Removal or manipulation should only be possible with destruction or visible, irreversible change.
In order to increase the counterfeiting security of the labels even more, the demand has been increasingly placed on the labels themselves to contribute to safety through a special design.
In particularly sensitive fields of application, a security level must also apply to the production of the labels. Too easy procurement and labeling of such labels as well as the production of plagiarism would allow unauthorized persons the unauthorized distribution of articles.

However, this additional counterfeiting security must not preclude subsequent identification of the bonded label for originality by a fast, clear, simple and non-destructive method.

• Es soll schnell beschriftbar sein.
• Es soll ein hohes räumliches Auflösungsvermögen erreicht werden.
• Es soll in der Anwendung möglichst einfach sein.
• Die Zersetzungsprodukte sollen nicht korrosiv wirken.

Powerful controllable lasers for baking markings such as fonts, codes and the like are widely used today. Amongst others, the following requirements apply to the material to be labeled:

• It should be writable quickly.
• It should be achieved a high spatial resolution.
• It should be as simple as possible in the application.
• The decomposition products should not be corrosive.

In addition, further requirements are made for special cases.
The characters should be so rich in contrast that they can be read error-free even in unfavorable conditions over long distances.
High temperature resistance should be given, for example to over 200 ° C.
Good resistance to weathering, water and solvents is desired.

Known materials used for this, such as printed paper, anodised aluminum, painted sheet metal or PVC films, do not meet all of these requirements.

In DE G 81 30 861 a multilayer label of a thin and a thick self-supporting, opaque pigmented lacquer layer is disclosed. Both layers consist of an electron beam-hardened solvent-free applied paint, wherein the layer thicknesses are different. The labeling of the label takes place in that with the aid of a laser, the upper thinner lacquer layer is burned away, so that the lower thicker lacquer layer is visible, the lower layer preferably has a contrasting color to the former.
This lettering is a type of engraving, which eliminates the manipulation possibilities as with traditional printing with inks and inks. The label is due to the raw materials used and the manufacturing process set so brittle that removal of the same from the adhesive substrates is possible only with destruction.

Such laser labels are used especially for a rational and variable labeling for the production of sign sets. These sets of signs contain the complete number of labels that are required, for example, in a motor vehicle for components subject to mandatory labeling (VIN plate, signs for tire pressure, trunk load, characteristics for engines and units, etc.).

EP 0 645 747 A shows a laser-inscribable multilayer label material which comprises a first layer, a second layer differing optically from the first layer, wherein the first layer is laser-irradiated in accordance with a desired font or print image to visualize the surface the second layer is removable. Between the layers, a transparent plastic film forming a carrier layer is furthermore arranged

DE 44 21 865 A1 shows a Einschichtlaseretikett of a carrier layer made of plastic, which contains an additive which shows a color change under laser irradiation
The carrier layer is coated on one side with a self-adhesive, which is optionally covered with a release paper or a release film.

In all the above-mentioned labels after applying to an object a high security against counterfeiting, because the labels can be labeled only with technically sophisticated, thus expensive and thus not accessible to all lasers, so that the equipment to copy the aforementioned labels or change can, at least in the past, for the most part, be more expensive than the product of interest. Furthermore, the high brittleness of the material in manipulation and Entfemungsversuchen causes destruction of the label.

With the technical progress, however, such lasers have become increasingly cheaper, so that the purchase of this particular for larger products such For example, motor vehicles, which are provided, inter alia, in the engine room for labeling with such a label, in an increasing number of cases worthwhile.
Then the production of unauthorized plagiarism by the easy and freely accessible procurement of laser etiquette pre-material and inter-current widespread use of laser marking equipment is greatly simplified.

Labels in the automotive industry play a very important role, because the marking of vehicles, vehicle parts and other original components, especially in the automotive industry, is a given requirement of the market due to the necessity of the proof of origin and the traceability.

For a long time it was state of the art to use for this purpose the embossed metal plates already mentioned, which were fastened by means of rivets to the corresponding component. This technology has in addition to major process cost disadvantages, deficiencies in flexibility and logistical effort and the current focus in the disadvantage that these riveted metal signs can be easily replaced and replaced by lmitate.

As a result of these principle disadvantages, laser label technology has become widely used, especially in the automotive industry.

With regard to _" forgery-proofness", the laser foil, as known from DE G 81 30 861 and obtainable, for example, as tesa 6930® from the company Beiersdorf, as already stated, offers the best prerequisites for documenting possible manipulation attempts, and thus because of its very brittle product structure to thwart.
The laser-printed label can only be removed at a very high cost and under certain conditions in a non-destructive way from its original bonding substrate.
This effort is so high that the said label all common Ablösbarkeitsprüfungen the main testing institutions such as "Examination of factory plates from plates, sheets and foils and their attachment by gluing" of the Federal Motor Transport Authority and "Marking and Labeling System Materials MH 18055" by Underwriters Laboratories Inc. without any problems.

This certified security against counterfeiting, which is always to be seen in relation to the effort required for manipulation, must face increasing demands with regard to "guaranteeing originality". This means that it should be documented with the aid of a glued laser label that the marked component is an original. Since, as already mentioned, the laser film as well as laser marking systems are freely available on the market, there is a possibility for organized crime on a large scale. Stolen vehicles can be equipped with the help of the mentioned hardware and the freely available laser foil with new labels that are scarcely or not at all distinguishable from the actual original labels.

This is the point where the solution according to the invention starts and clearly limits, if not prevents, the possibilities of counterfeiting and plagiarism
This is done by customizing the label to be used in the car and delivering it exclusively to the customer.

• es muß leicht und schnell identifizierbar sein und
• es darf nicht nachstellbar sein.

This individualization must fulfill two important criteria, namely

• it must be easily and quickly identifiable and
• it must not be adjustable.

By means of these two criteria one can ensure that only the authorized entity, in this case the automobile operator, is able to define and mark components as originals.

Initial attempts to individualize the carrier material of the label are disclosed in DE 199 04 823 A1. Here, a method for producing a film is described in which initially a support carrier film is embossed by means of an embossing tool, wherein the embossing tool has holographic structures. Subsequently, a film is produced on the embossed support carrier film, so that at least one hologram appears on the film.

The object of the invention is to provide a label which meets the above requirement of improved security against counterfeiting and furthermore has in particular high contrast, high resolution, high temperature resistance and easy application.

This object is achieved by a label as it can be obtained according to claim 1. The subject of the dependent claims are particularly advantageous embodiments of the label.

Accordingly, the invention relates to a label with increased anti-counterfeiting security from at least one lacquer layer, obtainable in that the lacquer layer is preferably applied solvent-free on a printed support carrier film and then cured.

It has proven to be advantageous if the lacquer layer is self-supporting and opaque pigmented and if the lacquer layer is electron beam hardened.

Furthermore, it has proved to be advantageous if the support carrier film is a plastic film, in particular of polyester.

The printing of the support carrier film takes place in particular by the flexographic printing process, because the UV flexographic printing process has a very high degree of freedom with regard to the design of geometries and can provide good print quality, especially for web-like materials from paper to film at the lowest possible price. With this technology, it is possible to transfer lines of fields, images, logos, fonts, etc. of different size and type from the cliche to the printing substrate.

• Druckvorstufe (reprotechnisch Ausarbeitung des Druckklischees)
• Druckplatte
• Druckformataufbau
• Bedruckstoff
• Rasterwalze
• Druckfarbe
• Farbgebung
• Druckspannung

Here are the most important influencing factors for this process:

• Pre-press (reprotechnical preparation of the printing plate)
• printing plate
• Print format structure
• substrate
• anilox roller
• printing ink
• coloring
• compressive stress

In the above-described use of the tamper-resistant, laser-writable label, logos and fonts of varying complexity are desired to be preferred by automobile manufacturers; Here, the UV flexographic printing is well applicable.

For this purpose, a cliché provided with the logos and fonts is wetted with printing ink and transferred to a plastic film. The ink can then be cured by physical activation (thermal, radiation chemistry) on the film. For this purpose, the color should undergo a high adhesion to the film substrate; this is indispensable for further processing. A pressure anchorage must be checked before further processing. For this one uses the cross-hatch test (DIN EN ISO 2409). The pressure should reach at least one rating of Gt 02 in the crosshatch test.

To achieve a high bond adhesion / pressure anchorage, a corresponding selection or formulation of the printing ink as a function of the film material and / or the use of a pretreatment method for the printing film is necessary. Preferably, here the corona treatment can be selected, which can be used inline printing. When using a PET film, the surface tension should be set to> 50 mN / m. This can be measured with standard test inks.

Depending on the UV emitter, the UV curing should have a percentage power setting between 50% and 100% in order to ensure sufficient flexibility of the printing for the further processing processes.

In order to achieve a visible and sensible impression on the laser label later, the print should have a height of 0.1 μm to 15 μm. Preferably, a height of 1 to 5 microns to choose. Also, the pressure impression and expression can be varied by the course of the pressure points.

To realize the invention, the other conventional printing methods can be used, which are known as high-pressure process. These include book and screen printing.

The backing film can be printed with a variety of designs, such as company logos or advertising. The printing of the support carrier film produces a negative impression on the visible surface of the first lacquer layer of the label according to the invention.

It is particularly preferred if the impression of the printed support carrier foil in the first lacquer layer is present as a depression of 0.1 to 15 μm, preferably of 1 to 5 μm.

1. a) Trägerschicht aus Kunststoff, die
2. b) ein Additiv enthält, das unter Laser-Bestrahlung einen Farbumschlag zeigt, und die
3. c) einseitig mit einer Selbstklebemasse beschichtet ist, welche
4. d) gegebenenfalls mit einem Trennpapier oder einer Trennfolie abgedeckt ist.

In an advantageous embodiment of the invention, the label consists of a

1. a) carrier layer made of plastic, the
2. b) contains an additive which shows a color change under laser irradiation, and the
3. c) is coated on one side with a self-adhesive, which
4. d) is optionally covered with a release paper or a release film.

The carrier layer consists of a lacquer, in particular of a cured lacquer, preferably a radiation-cured lacquer, in particular of an electron beam-cured polyurethane acrylate lacquer. In an alternative embodiment, the carrier layer is made of a polybutylene terephthalate
The carrier layer preferably has a thickness of 10 to 200 .mu.m, in particular from 50 to 100 .mu.m.
Suitable carrier layers continue to consist of plastics such as polyesters, poly (meth) acrylates, polycarbonate and polyolefins and radiation-curable systems such as unsaturated polyesters, epoxy, polyester and urethane acrylates, as well as for UV printing inks Application, in particular those of a base polymer according to DE G 81 30 861, namely aliphatic urethane acrylate oligomers.

The additive may be a pigment, especially copper hydroxide phosphate or iriodine, and may be used in addition to the titanium dioxide additive.
The additive can be used.

Suitable additives are, in particular, color pigments and metal salts, in particular copper hydroxide phosphate or else iriodin, a pearlescent pigment, such as is commercially available from Merck. These additives are added to the base polymer (as described, for example, in DE G 81 30 861), in particular of the order of a few parts per thousand up to a maximum of 10 percent, preferably in amounts of 0.1 to 10 percent by weight, in particular 0.5 up to 5% by weight, based on the total weight of the carrier layer, admixed. After production of sheet material by known methods such as extrusion, casting, coating, etc. with optionally subsequent radiation-chemical crosslinking, such films are coated with self-adhesive compositions which are to be adapted to later application purposes.

A cover with siliconized release paper then gives the typical structure for starting material from which labels can be made.

Using standard lasers, especially the popular Nd-YAG solid-state laser with a wavelength of 1.06 μm, a change in color or color changes occurs at the point of impact of the laser on the surface of the material, resulting in sharp, high-contrast labels and markings.

In a further advantageous embodiment, a second, in particular self-supporting, opaque pigmented lacquer layer is preferably applied solvent-free on the first lacquer layer, which is then in particular electron beam hardened.

It has proven to be particularly advantageous if the second lacquer layer contains an additive of at least 5% by weight, preferably 7% by weight, which is fluorescent or phosphorescent or which is suitable for magnetic or electrical labeling.

In a further advantageous embodiment, a color with a fluorescent or phosphorescent additive is printed on the first lacquer layer or on the side of the second lacquer layer opposite the first lacquer layer.

In the case of two-layer and multi-layered labels, a suitable additive can be incorporated in the second lacquer layer which is decisive for the writing. The first lacquer layer itself, for example for the glossy type plates, thus remains unchanged, only with the laser engraving, the second lacquer layer is partially exposed at the points of the label. If color pigments, colored particles, colored fibers and the like are present in the white second lacquer layer, these become visible at the engraved areas.

The coloring particles may be fine color pigments or else preferably visible particles of the order of 0.1 to 5 mm. When using finely ground color pigments, a slight color change of the lettering is produced, with the visible particles a characteristic color mosaic. When using daylight fluorescent colors, the "fingerprint" can be recognized without any aids, which is often undesirable. Preference is therefore given to using color pigments or particles which do not absorb in the region of visible light and are therefore invisible under normal circumstances - it is only when the label is illuminated with a lamp of suitable wavelength that the color pigments are excited and light up in a characteristic way.
In addition to color pigments excited by IR radiation, mainly UV-active systems are used. Also suitable in principle are phosphors which are produced by electron beams, X-rays and the like. are stimulated and thermochromic pigments reversibly change color when changing temperature - but in these cases, the implementation of identification on the bonded label in practice cumbersome and expensive than the visualization by means of light of suitable wavelength.

When selecting the color pigments, care must be taken that they are sufficiently stable for the production process of the labels (film production, adhesive coating) and do not change irreversibly in the process conditions (optionally thermal drying, electron beam or UV curing, etc.). It is advantageous for continuous use of the labels that these usually sensitive phosphors are embedded in a polymer matrix and additionally protected by the cover layer. Further measures against mechanical abrasion as well as protection against direct oxygen and water contact are not necessary.

Different color pigments and substances can be used for the application according to the invention. Most widely used are photoluminescent (phosphorescent) or fluorescent pigments which are excited only or predominantly by UV radiation and emit in the visible region of the spectrum (for an overview see, for example, Ullmann's Enzyklopadie der technischen Chemie, 4th Edition, 1979, Verlag Chemie) , However, IR-active luminescent pigments are also known. Examples of systems with UV fluorescence are xanthenes, coumarins, naphthalimides, etc., which are sometimes referred to in the literature under the generic term _" organic phosphors" or "optical brighteners". The addition of a few percent of the relevant phosphors is sufficient, and in particular the integration into a solid polymer matrix is favorable in terms of luminosity and stability. For example, formulations with RADGLO® pigments from Radiant Color NV / Holland or Lumilux® CD pigments from Riedel-de-Haen can be used. Also inorganic phosphors are suitable; As long photoluminescent substances, especially with the emission of light in the yellow range, metal sulfides and oxides, usually in combination with suitable activators, have proven favorable. These are available, for example, under the trade name Lumilux® N or as luminescent pigments improved in terms of stability, luminosity and persistence under the trade name LumiNova® from Nemoto / Japan.

These dyes / pigments listed by way of example are incorporated and coated in the formulation of the second lacquer layer in amounts of 0.1 to 50% by weight, preferably 1 to 25% by weight, very particularly preferably 7% by weight , After the final adhesive coating of the second lacquer layer and optionally Covering with release paper or release foil, the label pre-material is available for customer-specific use.
After stamping / laser cutting the desired label geometries and the final inscription by laser beam with lettering, barcodes, logos, etc., the label is in its final form. When incorporating, for example, long-luminescent pigments into the lacquer layer, the label, after appropriate stimulation of the luminescent pigments, has a characteristic afterglow in the region of the laser inscription and at the edges, which permits easy and rapid identification as original label. Apart from the special light source and, if necessary, a screen against disturbing ambient light, no further complex equipment is necessary - after the test the label remains unchanged.

Labels of this type, which contain phosphors, especially those emitting only after UV or IR excitation in the visible wavelength range, in the second resist layer are also suitable for precisely fitting production (printing, stamping, application, etc.). Instead of separately applied printing or timing markings, the light emission of the paint layer can be used for processing: especially after labeling and cutting the labels by means of laser beam from unpunched roll material excitation and emission can be used in a downstream control unit at a defined location of the label Equipment can be used as a tax stamp for further processing steps or for the production of the next label.

An alternative to the use of phosphors is the incorporation of substances into the second lacquer layer, which can be detected magnetically or electrically. Magnetic field changes, such as alarm labels for garments, for example, are possible in principle, but not predestined for the fields of application (identification of machine and car parts predominantly made of metal).
On the other hand, as a hidden security level it is advisable to add substances to the second lacquer layer which lead to an electrical conductivity of the layer. With suitable measuring devices which are portable, easy to use and reasonably priced too and suitable electrodes, the conductivity of the lacquer layer can be determined directly on the bonded label. The electrodes are stopped at two different points A and B of the lacquer layer and a voltage is applied. In the presence of a continuous electrical conductivity between A and B, a current flow can be measured, which may have a characteristic value depending on the type and amount of the additive used. Since even when using the label directly on metals, the paint layer is separated from the conductive metal by the electrically insulating adhesive layer, no erroneous measurements are to be feared.

A counterfeiting by subsequent manipulation is particularly excluded by the fact that the conductivity measurement can be done not only from edge to edge of the labels, but between any exposed by Belaserung points: so that here a conductivity can be detected, the entire resist layer must be consistently three-dimensional conductive which can only be guaranteed in the context of the original manufacturing process. Such a laser-writable label can be produced by adding electrically conductive substances to the formulation of the second lacquer layer; This can be done in addition to the previous pigments or at least partially in replacement of the existing pigments in order to maintain the good processing properties of the paint pastes. In principle, electrically conductive metallic, organic, polymeric and inorganic substances are suitable as conductive additives, the use of metals being preferred. Especially for white or light lacquer layers, the own color of the conductive additive has to be considered for the selection. Conductive carbon black is also suitable, but only for black or dark paint layers.

In order to ensure a good conductivity, a minimum limit concentration of additive should be ensured, so that sufficient particles are present in the lacquer layer to touch and have contact with each other. If this limit concentration is undershot, a conductive path from A to B is no longer ensured in the three-dimensional structure of the base layer. Preference is therefore given to using metallic particles, preference being given to fibers having a high length to cross-sectional ratio, since in this case a three-dimensional one is used with lower concentrations Conductivity can be ensured as with spherical particles; In addition, the color change of the lacquer layer with the fibers is smaller. The metals used are preferably cost-benefit considerations copper, iron, aluminum and steel and their alloys, but also expensive, highly conductive metals such as silver, gold are suitable. The fiber dimensions are 0.1 to 50 mm in length and cross sections of 1 to 100 .mu.m, wherein preferably metal fibers with a diameter of 2 to 20 microns at a cross-sectional to length ratio of about 1: 100 to 1: 1000 are used. Such fibers are incorporated homogeneously with 0.5 to 25 wt .-%, preferably 2 to 10 wt .-% in the known recipe and coated according to DE G 81 30 861 and cured.
After adhesive coating and covering with release paper label material is available, which can be labeled by laser beam. By removing the upper lacquer layer, the lettering of the second lacquer layer is exposed in the area of the laser inscription - when a voltage is applied via suitable electrode contacts at two different points A and B of these inscriptions, a conductivity is measured that is characteristic of the lacquer layer and, among other things, by quantity and type of conductive additive is determined. Thus, it is possible to produce customized label pre-material via defined recipes.

In the said further advantageous embodiment, a color with a fluorescent or phosphorescent additive is printed on the first lacquer layer or on the side of the second lacquer layer opposite the first lacquer layer.
In particular, special colors with phosphors, daylight colors or, in particular, color pigments stimulable by IR or UV radiation are used. After printing, the resulting material can be coated with self-adhesive composition by default, dried and covered with release paper.

For the luminescent (phosphorescent) or fluorescent pigments, reference is made to the previous description of the additives.

In principle, phosphors which are suitable by electron beams, X-rays and the like are also suitable here. are excited as well as thermochromic pigments that are present in Reversibly change the temperature change; also the use of electrically conductive colors is possible.

This additional marking is not visible from the front in the area of the laser inscription (except for a transparent or translucent layer), but only around the label on the edge. In order to ensure a clear recognizability at the label edge, strongly luminous color pigments are printed in sufficient layer thickness. Nevertheless, the additional security is concealed and therefore inconspicuous. This security marking is protected against external access, since the pressure is embedded between the label film and the adhesive layer: subsequent manipulations are not to be feared, since a replacement of the known laser labels is possible only with destruction of the paint film.

Customer-specific "fingerprints" of the labels can be realized by printing different colors or patterns. Especially regular lines and line patterns create characteristic patterns of luminous dots on the label edge and are also particularly cost-saving and material-saving. After punching or laser cutting of the label and the application on the adhesive substrates a pattern with respect to colors and geometries can be identified by selecting a suitable illumination source at the edge of the label.

Especially logistical and cost-wise, the advantage of this security marking makes itself felt. Commercially available inks and non-specific labelstock can be used while the latter is otherwise customizable. However, since such standard pre-material is only used by the label manufacturers as an intermediate product for their own production and is not freely available on the market, unauthorized access is ruled out. In addition, small lot sizes and short delivery times are possible.

In the embodiment according to the invention, for example, the two-layer film material described in DE G 81 30 861 is used. Before the coating and Covering with release paper, however, the reverse side is printed over the entire surface, with scattering pressure or, in particular, with defined geometries. Printing inks with a high content of luminescent pigments are preferably applied by screen printing in order to achieve layer thicknesses in the range of 0.5 to 50 μm, preferably 2 to 25 μm.
After the adhesive coating and covering, the label pre-material for the desired formats and sizes is punched or cut out by laser beam. In the case of these labels, there is no indication of a hidden counterfeiting stage in the bonded state, provided that phosphors are selected whose light emission is produced by excitation with light outside the visible range; only after irradiation with suitable light sources does an excitation of the luminescent pigments take place at the edges of the label. Here and only here are therefore visually detect marks that give a predetermined pattern of illuminated spots. Through different line widths and heights, the luminous dots can be made different sizes. Thus, an easily detectable security level can be realized simply, cost-effectively and, if required, customer-specific via geometry and color selection.

The first lacquer layer, formed by a cured, ie crosslinked lacquer, preferably has a thickness of 1 to 20 .mu.m, in particular 5 to 15 .mu.m, the second lacquer layer preferably having a thickness of 20 to 500 .mu.m, in particular 30 to 100 .mu.m.

In principle, four types of lacquer can be used for the object according to the invention, provided their stability is sufficient, for example acid-hardening alkydmelamine resins, addition-crosslinking polyurethanes, free-radically curing styrofoam and the like. However, radiation-curing paints are particularly advantageous, since they cure very quickly without lengthy evaporation of solvents or the action of heat. Such paints have been described for example by A. Vrancken (color and paint 83.3 (1977) 171).

Both paint layers have in a preferred embodiment against each other a maximum color contrast.

For the label according to the invention preferably consists of an opaque upper layer, which can be easily burned by a laser beam, a lower second layer, in particular in a contrasting color to the first, wherein the lower layer is such that it is not easily burned by the laser beam.

In a further preferred embodiment, an additional adhesive layer of 5 to 70 .mu.m in thickness and, if necessary, a release paper are arranged on the second lacquer layer.

The third layer of a pressure-sensitive adhesive, hot-melt adhesive or reactive adhesive or the like is intended for bonding to a substrate. The thickness of the adhesive layer is preferably 5 to 70 μm, in particular 10 to 30 μm.

By Sichefieitsfeature there is no impairment of the already existing laser label; the mechanical, physical and chemical resistance are not changed. From the application point of view, the label experiences no losses; Regarding inscribability with a laser, readability of the information.

The first resist layer is applied to the backing sheet and cured by exposure to a high energy electron beam (150 to 500 kV) under effectively oxygen-free conditions. To improve the adhesion between the two layers of paint, a slightly adhesive surface or a small amount of oxygen can be used to set a slightly adhesive surface.
On this first layer, the second is applied and also cured by electron beam. Where appropriate, then the coating with the adhesive and then, if desired, the cover with the protective paper. Thereafter, the polyester film is peeled off, so that the free surface of the first, upper layer comes to light. Depending on the shape of the surface of the polyester film, this is glossy, smooth, matt or embossed.

• Die Etiketten sind nach dem Applizieren schnell zu erkennen, sie sind optisch sichtbar und fühlbar.
• Die Identifikation ist ohne Hilfsmittel möglich, d.h., eine Authentizitätsprüfung kann ohne UV-, IR-Lampen etc. vorgenommen werden.
• Da die Identifikation eindeutig ist, ist die Gefahr einer Fehlbeurteilung gering.

The label according to the invention is distinguished by a multiplicity of advantages which were unforeseeable for the person skilled in the art.

• The labels can be recognized quickly after application, they are visually visible and palpable.
• The identification is possible without aids, ie, an authenticity check can be made without UV, IR lamps, etc.
• Since the identification is unique, the risk of misjudgment is low.

The label is characterized by a very high counterfeit security due to the special manufacturing process. Because of the printing process, the risk of imitation laser-markable label material with negative impression is very low.
It is a fast communication and implementation of counterfeit security possible, so a quick information to all important testing bodies such as workshops, police, customs without special effort.

A customer-specific marking is implemented in the first coatable lacquer layer, which is visible, perceptible and measurable as a depression in the lacquer layer. Marking may include various types of graphics and logos, as well as lettering, subject to more extensive test results. Combinations of both are possible. For example, one could bring the logo of the car manufacturer, coupled with the lettering in the film surface. This symbol is scattered across the entire width of the material to ensure that at least one of these tamper-evident symbols is in each label produced (a variable to be defined). As already mentioned, this is a very fine depression of the surface in conjunction with a roughening. The security symbol is therefore recognizable by its languor with the eye and sensory measurable by its depression.

This "embossing" is prepared in a step upstream of the actual production process by means of a kind of "negative" and then integrated into the very complex and hardly imitatable production of the standard laser films.
Thus, an adjustment of this originality feature is not possible.

Figur 1

den Aufbau des erfindungsgemäßen Etiketts.

Based on two embodiments, the invention will be explained below without limiting it. It shows

FIG. 1

the structure of the label according to the invention.

In the construction of the label according to the invention shown in FIG. 1, the first lacquer layer 10 is located on the second thicker lacquer layer 20 and, according to a preferred embodiment, on a layer of an adhesive 30, in particular a pressure-sensitive adhesive, which is covered with a release paper 40.
In the first lacquer layer 10, the impressions 11 formed by wiping out the first lacquer layer 10 on a printed support carrier foil can be seen. A regular pattern here is the word _" tesa" ®, which is surrounded by a frame.

example 1

The substrate to be printed, in this case a polyester film (Hostaphan RN 75®) from Mitsubishi, is treated before printing by a corona treatment to the desired surface tension. For this purpose, a corona station VETAPHON-Corona-Plus DK-E-Treater ET 2- with an output of 0.2 to 2.0 kW can be used. Advantageous for further processing is the adjustment of the surface tension to> 50 mN / m.

A cationic curable UV varnish SICPA 360076 from SICPA, Aarberg, which is tinted blue, is used. By adding 5% by weight of cylinder repellent, the ink is optimized for processing

Using a UV flexo printing machine ARSOMA em 410 or em 510, the pretreated polyester film is printed on a flexographic printing station at a speed of 30 m / min. The precisely defined ink transfer to the flexographic printing plate is achieved by means of a corresponding anilox roller in the Negative doctor blade method. It then takes place the color transfer from the cliché to the film substrate in a color height of 3 to 4 microns.
The application of paint on the film substrate is cured by powerful UV radiation tubes. For this purpose, a UV station UV UV station GEW with a radiator output of 110 W / cm and a wavelength of 365 nm is used. The backing film is now ready for further processing

• Eine Schwarzpaste A durch Anreiben mit 12% Ruß FCF (mittlerer Teilchendurchmesser 23 µm) am Dreiwalzenstuhl und
• eine Weißpaste B durch Anreiben mit 45% eines Al und Si stabilisierten Rutilpigments (TiO₂-Gehalt 90%, Dichte 3,9 g/m²).

Then, a commercial polyurethane acrylate of long-chain polyester diol, aliphatic diisocyanate and terminal acrylic groups (molecular weight about 1500, functionality 2) is mixed with 20% hexanediol bisacrylate. A highly viscous liquid of about 10 Pa * s is obtained. From this is made:

• A black paste A by rubbing with 12% soot FCF (average particle diameter 23 microns) on the three-roll and
• a white paste B by rubbing with 45% of an Al and Si stabilized rutile pigment (TiO ₂ content 90%, density 3.9 g / m ² ).

Paste A is coated at a thickness of 10 microns on a 50 micron thick biaxially stretched and embossed polyester film and cured by an electron beam of 350 keV with a dose of 1 Mrad under inert gas.

Then a white paste B with a thickness of 50 microns is applied and cured again with the electron beam under inert gas with a dose of 3 Mrad.

On this product, a pressure sensitive adhesive according to DE 15 69 898 A1 deleted, so that the layer has a thickness of 20 microns after drying. The pressure-sensitive adhesive is covered with commercial release paper.

Thereafter, the polyester film is peeled off, so that the impressed and otherwise mirror-smooth black surface of the product comes to light

This can be labeled quickly with a controllable power laser, for example with a bar code. The contrast is so high that the code over 1 m distance with the evaluation device is to be read error-free.

Heating the material to 200 ° C. for 1 hour results in shrinkage of less than 10% in the longitudinal and transverse directions. Immersion in water and / or weathering in the Weathermometer for 500 h leads to no impairment.

Claims (8)

1. Label with enhanced proof against counterfeiting, comprising at least one varnish layer (10, 20) obtainable by applying the varnish layer to a printed support carrier sheet and subsequently curing it.
2. Label according to claim 1, characterized in that atop the first varnish layer (10) a second varnish layer (20) is applied and is subsequently cured.
3. Label according to claim 1 and 2, characterized in that the first varnish layer (10) has a thickness of from 1 to 20 µm, in particular from 5 to 15 µm, and the second varnish (20) layer has a thickness of from 20 to 500 µm, in particular from 30 to 100 µm.
4. Label according to any of claims 1 to 3, characterized in that the two varnish layers (10, 20) exhibit maximum color contrast to one another.
5. Label according to any of claims 1 to 4, characterized in that on the first (10) or on the second (20) varnish layer there is an additional adhesive layer with a thickness of from 5 to 70 µm, and if necessary a release paper deposed thereon.
6. Label according to any of claims 1 to 5, characterized in that the support carrier sheet is a polymer film, preferably of polyester.
7. Label according to any of claims 1 to 6, characterized in that the printing (11) on the support carrier sheet has a height of from 0.1 µm to 15 µm, preferably a height of from 1 to 5 µm.
8. Label according to any of claims 1 to 7, characterized in that, in the first varnish layer (10), the impression of the printed support carrier sheet is present in the form of a depression of from 0.1 to 15 µm, preferably from 1 to 5 µm.