EP1716007A1 - Tamper-proof, color-shift security feature - Google Patents

Abstract

A tamper-proof security element includes at least one polymer spacer layer and two metal cluster layers. One or more of the layers, in addition to their function, fulfills a security feature in their color-shift set-up.

Description

Counterfeit-proof security feature with color shift effect

The invention relates to tamper-proof security features that have a color shift effect caused by metallic clusters that are separated from a mirror layer by a defined transparent layer.

From WO 02/18155 a method for counterfeit-proof marking of objects is known, the object having a marking consisting of an electromagnetic wave reflecting first layer being applied to a layer permeable to electromagnetic waves with a defined thickness, followed by a layer on this layer metallic clusters formed third layer follows, is provided.

The object of the invention is to provide a security feature with a color shift effect, the security feature should have additional security levels.

The invention therefore relates to a tamper-proof security feature, each consisting of at least one layer reflecting electromagnetic waves, a polymeric spacer layer and a layer formed by metallic clusters, characterized in that one or more of the layers perform additional security functions in addition to their function in the color-shift effect setup.

Flexible plastic films, for example made of PI, PP, MOPP, PE, PPS, PEEK, PEK, PEI, PSU, PAEK, LCP, PEN, PBT, PET, PA, PC, COC, POM, ABS, PVC, are preferably suitable as the carrier substrate , The carrier films preferably have a thickness of 5 to 700 μm, preferably 8 to 200 μm, particularly preferably 12 to 50 μm. The foils can be clear or matt (especially matt printed). The scatter on matt foils causes a significant change, particularly in the intensity in the color spectrum, so that a different color code is created than with clear foils. Furthermore, metal foils, for example Al, Cu, Sn, Ni, Fe or stainless steel foils with a thickness of 5-200 μm, preferably 10 to 80 μm, particularly preferably 20-50 μm, can also serve as the carrier substrate. The films can also be surface-treated, coated or laminated, for example with plastics, or painted.

200 g / m ² is used - Further, as the carrier substrates also cellulose-free or cellulose-containing paper, ther oaktivierbares paper or composites with paper, for example, composites with plastics with a basis weight of 20 - 500 g / m ^2, preferably 40th

The carrier substrate can also be provided with a release-capable transfer lacquer layer.

An electromagnetic wave reflecting layer is applied to the carrier substrate. This layer can preferably be made of metals such as aluminum, gold, chromium, silver, copper, tin, platinum, nickel or tantalum, semiconductors such as silicon and their alloys such as nickel / chromium, copper / aluminum and the like or one Printing ink with metal pigments exist.

The electromagnetic wave-reflecting layer is covered over the entire surface or partially by known processes, such as spraying, vapor deposition, sputtering, or, for example, as a printing ink by known printing processes (gravure, flexographic, screen, digital printing), by painting, roller application processes, slot nozzle (slot) Eye), dip (roll dip coating) or curtain coating (curtain coating) and the like applied.

A method using a soluble paint application for producing the partial metallization is particularly suitable for partial application. In a first step, a paint application that is soluble in a solvent is applied to the carrier substrate, in a second step this layer optionally by means of an inline plasma, corona or

Treated flame process and in a third step a layer of the metal to be structured or the metal alloy is applied, whereupon in a fourth step the paint application is removed by means of a solvent, optionally combined with a mechanical action.

The soluble paint is applied partially, the application of the metal or

Metal alloy is made over the entire surface or partially.

However, the partial layer reflecting electromagnetic waves can also be produced by a customary known etching process.

The thickness of the layer reflecting electromagnetic waves is preferably approximately 10-50 nm, although higher or lower layer thicknesses are also possible.

If metal foils are used as the carrier substrate, the carrier substrate itself can already form the layer reflecting electromagnetic waves.

The reflection of this layer for electromagnetic waves is preferably 10-100%, in particular depending on the thickness of the layer or the metal foil used.

The subsequent polymeric spacer layer or the polymeric spacer layers can also be applied over the entire surface or preferably partially.

The polymeric layers consist, for example, of conventional or radiation-curing, in particular UV-curing, dyeing or coating systems based on nitrocellulose, epoxy, polyester, rosin, acrylate, alkyd, melamine, PVA, PVC, isocyanate. , Urethane or PS copolymer systems.

This polymeric layer essentially serves as a transparent spacer layer, but depending on the composition it can be absorbent and / or fluorescent or phosphorescent in a certain spectral range. If necessary, this property can also be added by adding suitable chromophore. A suitable spectral range can be selected by selecting different chromophores. As a result, in addition to the tilting effect, the polymer layer can also be made machine-readable. For example, in the blue spectral range (in the range of approximately 400 nm), a yellow AZO dye, for example anilides, rodural, eosin, can be used. The dye also changes the spectrum of the marking in a characteristic manner.

When using a fluorophore with excitation outside the visible range (e.g. in the UV) and radiation in the visible range, a marking with a color change when illuminated can even be generated if a suitable concentration is selected. Optimally, the layer structure at the targeted observation angle has a spectrum with high absorption in the wavelength range of the emission of the fluorophore. Such a marking could also be combined well with the UV test lamps already used at checkouts.

Another way to create a reversible color change is to use a switchable chromophore such as Bacteriorhodopsin To Use. When illuminated with a suitable wavelength (bacteriorhodopsin between 450 mm and 650 mm) and sufficiently high intensity, such chromophores change their absorption behavior. Bacteriorhodopsin undergoes a structural transformation, which changes back to its original state after the lighting is switched off and switches the color of the chromophore between purple and yellow. The integration of such chromophores in the layer structure, e.g. the spacer layer, changes the absorption spectrum, the switching behavior also occurring.

This polymeric layer can, depending on the quality of the adhesion on the carrier web or a layer which may be underneath Dewetting effects show what leads to a characteristic, macroscopic lateral structuring.

This structuring can be induced or specifically changed, for example, by modifying the surface energy of the layers, for example by plasma treatment (in particular plasma functionalization), corona treatment, electron or ion beam treatment or by laser modification.

Furthermore, it is possible to apply an adhesion promoter layer with different surface energies in some areas.

The polymeric spacer layer preferably has regions of different thickness. Through a defined variation in the thickness (gradient, defined steps, defined structures) of the polymeric spacer layer, a combination of different color shift effects is created in a finished security feature (multi-color shift effect).

The thickness of the layer can be varied specifically in a wide range, for example in a range from 10 nm to 3 μm.

With a spacer layer thickness of more than approx. 3 μm, the layer structure no longer produces a color that is recognizable to the human eye, but, depending on the mirror material, a slightly darker metallic impression compared to the pure mirror. This is due to the fact that the spectrum becomes more complex with increasing layer thickness (multipeak) and can no longer be resolved. For readers, however, the spectrum is still well measurable and even highly characteristic, the maximum spacer layer thickness to be measured depends on the resolution of the respective device. This is one way of creating an inconspicuous but machine-readable marking. Furthermore, when applying the polymeric spacer layer, a specific, defined layer thickness profile can be set, either in one application step or by applying several layers, which in turn can be full or partial depending on the desired layer thickness profile.

The course of the layer thickness can also be designed in the form of a step structure, with different thicknesses of another polymer layer being partially applied to a base layer.

It is also possible to apply several layers of different polymers, for example polymers with different refractive indices.

In a particular embodiment, at least one layer of the polymeric spacer layer can consist of a piezoelectric polymer, electrical properties here being able to be detected either by direct contact or by an electrical field. Depending on the thickness or the course of the thickness or on the change in layer thickness of the spacer layer, a characteristic interaction with electrical or electromagnetic fields can therefore be demonstrated by simple optical detection (e.g. with the naked eye, optical photometer and / or spectrometer).

In a particular embodiment, at least one layer of the polymeric spacer layer can have optically active structures, for example diffraction gratings, diffraction structures, holograms and the like, which can be embossed into the polymeric spacer layer, preferably before complete curing. A corresponding method is known for example from EP -A 1352732 A or from EP -A 1310381.

The polymeric spacer layer is preferably applied by means of a printing process, for example by gravure printing. The fine structure in the spacer layer transferred by the printing cylinder or the printing plate then forms an additional forgery-proof feature. Depending on the printing tool used, the composition of the varnish of the polymeric spacer layer and the manufacturing parameters, this fine structure forms a forensic and / or visible security feature that allows an unambiguous assignment to the manufacturing process (fingerprint). Furthermore, for example, several different layer thicknesses of the polymeric spacer layer can be produced with a single cylinder. Different codes result from the different thicknesses. Another range of thicknesses of the polymeric spacer layer is then produced with another cylinder, it being possible for some codes to overlap. In the overlap area, the same code can be produced with two different cylinders, which results in a further forensic and / or visible security feature and allows unambiguous assignment to the manufacturing process (fingerprint). The additional fingerprint is used either as a forensic feature (3rd level feature) or as an additional code substructure.

Polymeric spacer layers which show cholesteric behavior are also preferably used. In addition to liquid crystal polymers, in which this behavior can be generated, this also show polymers with two intrinsic chiral phases, e.g. Nitrocellulose. By targeted excitation of the rare second phase of chirality, for example by mechanical or electromagnetic energy input (thermal, radiation) or by means of a catalyst, an additional characteristic security feature is generated by wavelength-selective polarization. The cholesteric behavior can lead to a characteristic change in the color spectrum, which can be detected by a reading device.

A full-surface or partial layer, formed from metallic clusters, is then applied to the polymer layer. The metallic clusters can consist, for example, of aluminum, gold, palladium, platinum, chromium, silver, copper, nickel, tantalum, tin and the like or their alloys, such as Au / Pd, Cu / Ni or Cr / Ni. Preferably can cluster materials are also applied, for example semiconducting elements of III. to VI. Main or second subgroup whose plasmon excitation can be triggered externally (for example via X-ray or ion radiation or electromagnetic interactions). As a result, a change in the color spectrum (eg change in intensity) or a blinking of the color shift effect becomes visible when viewed with a suitable reading device. The cluster layer can also have additional properties, for example electrically conductive, magnetic or fluorescent properties. For example, a cluster layer of Ni, Cr / Ni, Fe or core-shell structures with these materials or mixtures of these materials with the above-mentioned cluster materials has such additional features. Fluorescent clusters can also be produced using core-shell structures, for example, using Quantum Dots ^® from Quantum Dot Corp.

The cluster layer is applied over the entire area or partially, either exactly or partially congruently or offset to the full-area or partial layer reflecting electromagnetic waves.

The adhesion of the metallic cluster layer to the polymeric spacer layer can preferably be set in a defined manner by guiding the application process of the cluster layer, so that if the adhesive strength differs, a proof of manipulation is created by destruction of the color effect.

The varnish of the spacer layer can also be adjusted so that it shows good adhesion to the metal (cluster, mirror) but not to the base film. If this lacquer is printed over a partial Cu layer, when the element is detached, the mirror layer is separated in accordance with the structuring of the cluster layer. This creates a previously invisible evidence of manipulation. This cluster layer can be applied by sputtering (for example ion beam or magnetron) or evaporation (electron beam), or from a solution, for example by adsorption.

When the cluster layer is produced in vacuum processes, the growth of the clusters and thus their shape and the optical properties can advantageously be influenced by adjusting the surface energy or the roughness of the layer underneath. This changes the spectra in a characteristic way. This can be done, for example, by thermal treatment in the coating process or by preheating the substrate.

These parameters can also be changed in a targeted manner, for example by treating the surface with oxidizing liquids, for example with Na hypochlorite or in a PVD or CVD process.

The cluster layer can preferably be applied by means of sputtering. The properties of the layer, in particular the density and the structure, are adjusted above all by the power density, the amount of gas used and its composition, the temperature of the substrate and the web speed.

For application by means of printing technology, small amounts of an inert polymer, for example PVA, polymethyl methacrylate, nitrocellulose, polyester or urethane systems, are mixed into the solution after the clusters may have to be concentrated. The mixture can then subsequently be applied to the polymer layer by means of a printing process, for example screen, flexographic or preferably gravure printing, by means of a coating process, for example painting, spraying, roller application techniques and the like.

The mass thickness of the cluster layer is preferably 2-20 nm, particularly preferably 3-10 nm. In one embodiment, a so-called double cluster structure can be applied to the carrier substrate, a cluster layer being present on both sides of the spacer layer. A preferably black layer is applied under the first cluster layer. This black background can be applied either by means of a vacuum technology process, for example as unstoichiometric aluminum oxide or as printing ink by means of a suitable printing process, the printing ink being able to have additional functional features, for example magnetic, electrically conductive features and the like. A correspondingly colored film can also serve as a black or dark background.

By placing a black film on a double cluster setup, simple visual verification can be performed on site (simple test equipment). For example, a double cluster feature can be introduced as a viewing window in a bank note or credit card or the like. The optical detection of the presence of the double cluster feature is carried out by placing a black film, for example made of polycarbonate.

The clusters on both sides of the spacer layer can be applied to different thicknesses, each structured or full-area and / or consist of different materials in a structure.

If, for example, a polymeric spacer layer with a defined course of the layer thickness or a step structure is used, the metallic clusters are preferably deposited and directed at the steps or at certain points in the course of the layer thickness. This process can be intensified or reduced by suitable process management. For example, different optical effects are produced on microstructured surfaces than on smooth foils. This results in new (sub) codes. It is also possible to apply several layer sequences to a carrier substrate, whereby different color shift effects can be observed depending on the design of the reflective layer (full or partial) and depending on the structuring of the spacer layers or the design of the cluster layer (full or partial, register-accurate or overlapping with the reflective layer). For example, an optionally structured spacer layer, then a partial cluster layer, then in turn an optionally structured spacer layer, in turn a preferably partial cluster layer, which for example is partially overlapping with the first cluster layer, can be applied to a full-surface reflection layer. Such sequences of spacer layer and cluster layer can expediently be repeated 2 to 3 times. Analogously, such structures can be applied to a partially applied reflection layer, with different color shift effects being observed here, depending on the design of the partial reflection layer.

The layer structure thus produced can then be structured using electromagnetic radiation (e.g. light). Lettering, letters, symbols, characters, images, logos, codes, serial numbers and the like can be used e.g. can be introduced by means of laser radiation or engraving.

By appropriate choice of the radiation power, either the layer structure is partially destroyed or the thickness of the polymeric spacer layer is changed. The polymeric spacer usually swells in these areas, causing a change in color (peak shift to longer wavelengths). The partial destruction, on the other hand, means that the illuminated area either reflects metal (separation of the electromagnetic wave reflecting layer from the spacer layer) or that the material behind the mirror becomes visible. In this way, targeted structuring with colored, reflecting or colorless areas can be achieved. The lighting output can also be selected so that only the color effect is changed, whereby partial areas with defined different colors are created (multi-color tilt effect). The energy that is actually absorbed by the layer structure is essential for the change.

In a special embodiment, it is also possible to apply a cluster layer directly to a carrier substrate which is at least partially transparent in the visible spectral range; a spacer layer and a further cluster layer are then applied to this cluster layer, as described, a black layer then optionally being applied to this cluster layer , as already described, can be applied. A so-called inverse layer structure is thus obtained. (Fig. 4)

An inverse setup with a single cluster layer (application of the cluster layer to the carrier substrate, subsequent application of the polymeric spacer layer and the electromagnetic wave reflecting layer) can also be produced in an analogous manner, the properties of the individual layers corresponding to the preceding description.

The carrier substrate can also already have one or more functional and / or decorative layers.

The functional layers can, for example, have certain electrical, magnetic, special chemical, physical and also optical properties.

For setting electrical properties, for example conductivity, graphite, carbon black, conductive organic or inorganic polymers can be used. Metal pigments (for example copper, aluminum, silver, gold, iron, chromium lead and the like), metal alloys such as copper-zinc or Copper-aluminum or its sulfides or oxides, or amorphous or crystalline ceramic pigments such as ITO and the like can be added. Furthermore, doped or undoped semiconductors such as silicon, germanium or ion conductors such as amorphous or crystalline metal oxides or metal sulfides can also be used as additives. Furthermore, polar or partially polar compounds such as surfactants or non-polar compounds such as silicone additives or hygroscopic or non-hygroscopic salts can be used or added to adjust the electrical properties of the layer.

Paramagnetic, diamagnetic and also ferromagnetic substances such as iron, nickel and cobalt or their compounds or salts (for example oxides or sulfides) can be used to adjust the magnetic properties.

The optical properties of the layer can be determined by visible dyes or pigments, luminescent dyes or pigments that fluoresce or phosphoresce in the visible, in the UV range or in the IR range, effect pigments such as liquid crystals, pearlescent, bronzes and / or heat-sensitive Affect colors or pigments. These can be used in all possible combinations. In addition, phosphorescent pigments can also be used alone or in combination with other dyes and / or pigments.

Different properties can also be combined by adding different additives mentioned above. It is possible to use colored and / or conductive magnetic pigments. All of the conductive additives mentioned can be used.

All known soluble and non-soluble dyes or pigments can be used especially for coloring magnetic pigments. For example, a brown magnetic paint can be made metallic, for example silvery, by adding metals. Insulator layers can also be applied, for example. Examples of insulators are organic substances and their derivatives and compounds, for example dyeing and lacquer systems, for example epoxy, polyester, rosin, acrylate, alkyd, melamine, PVA, PVC, isocyanate, urethane systems, which are radiation-curing can be suitable, for example by heat or UV radiation.

Furthermore, forensic features can be introduced into one of the layers, which allow testing in the laboratory or with suitable test equipment on site (possibly with the feature being destroyed), e.g. DNA in NC lacquer, antigens in acrylate lacquer systems. For example, DNA can be adsorbed or bound to the clusters. Isotopes can also be added to the clusters or in the mirror material or be present in the spacer layer (e.g. Elemental Tag from KeyMaster Technologies Inc.). For example, a deuterated polymer (e.g. PS-d) can be used as a spacer layer or a low-level radioactive mirror material as a mirror.

These layers can be applied by known methods, for example by vapor deposition, sputtering, printing (for example gravure, flexographic, screen, digital printing and the like), spraying, electroplating, roller application methods and the like. The thickness of the functional layer is 0.001 to 50 μm, preferably 0.1 to 20 μm.

If necessary, the coated film produced in this way can also be protected by a protective lacquer layer or further refined, for example, by lamination or the like.

If necessary, the product can be applied to the corresponding carrier material using a sealable adhesive, for example a hot or cold seal adhesive, or a self-adhesive coating be, or embedded in the paper for example in the paper production for security papers by conventional methods.

1-6 show examples of security features according to the invention.

Therein 1 means the optically transparent carrier substrate, 2 the first layer reflecting electromagnetic waves, 3 the polymeric spacer layer, 4 the layer made of metallic clusters, 5 an adhesive or laminating layer, 6 a protective layer 7, a transfer lacquer layer, 8 one black layer, 10 the beam path of the incident and reflected light.

7 shows a structure personalized by electromagnetic radiation.

Show it:

Fig. 1 is a schematic cross-sectional view of a first permanently visible marking on a film with a double cluster setup.

Fig. 2 is a schematic cross-sectional view of a first permanently visible marking on a film with double cluster setup and beam path of the optical detection means, for example spectrometer, color measuring device, or the like.

Fig. 3 shows a direct double cluster setup with a black background

Fig. 4 shows an indirect double cluster setup with a black background

Fig. 5 shows a setup with partial reflection layer

6 shows a setup with a structured spacer layer of different thickness The coated carrier materials produced according to the invention can be used as security features in banknotes, data carriers, value documents, labels, labels, seals, in packaging, textiles and the like.

Examples:

Example 1 :

A Cr cluster layer with a thickness of 3 nm is applied to a polyester film with a thickness of 23 μm in a sputtering process. On this cluster layer, a urethane varnish as a polymeric spacer layer with a thickness of 0.5 μm is printed using gravure printing using a specially optimized printing cylinder. This is followed again by the deposition of a 3 nm thick Cr cluster layer. Finally, a black-colored film is laminated onto this cluster layer. A color shift effect from violet to gold is observed.

Example 2:

When producing a thin-layer structure as in Example 1, parts of the layers are structured in such a way that the tipping color with an underlying moiré pattern only becomes visible when the structured double cluster setup and the structured black background film are overlaid precisely. For this purpose, the polymer layer is structured like a chessboard in a double cluster setup, the edge length of the chessboard fields being less than 0.1 mm. The blackening of the background foil is structured with analog checkerboard fields. If the structured foils are precisely overlaid, both the expression of the moiré pattern and the tipping color can be observed. In this way, maximum security can be guaranteed by simple on-site testing.

Example 3:

In the production of a thin-layer structure as in Example 1, instead of applying the second cluster layer by vacuum technology, Clusters, which were produced by chemical synthesis in solution and are present as a dispersion in solution. For this purpose, such cluster-containing solutions are printed in very thin layers or adsorbed from the solution. If clusters are used that have additional properties, additional security can be generated. Silver nanopowder from Argonide can be used as powdered cluster materials for printing.

Magnetic pigments from Sustech can be used as magnetic cluster materials. Most suitable are ferrofluids or pigments in powder form of the type: FMA (super paramagnetic ferrite) with a hydrophilic coating. FMA mean primary particle size: 10 nm diameter. SSPH (Sequential Solution Phase Hydrolysis) particles from Nanodynamics or Nanopowders can be used as corshell clusters. For example, Au on SnO 2 or Au on SiO 2 particles with an inner diameter of 20 nm and an outer diameter of 40 nm can be used. The particles from Quantum Dot Corporation can be used as fluorescent particles: as core material CdS and as shell material ZnS. Core diameter: 5nm; Shell diameter: 2.5 nm.

Example 4:

In one embodiment, a printing cylinder with different cell volumes is produced in different areas over its width. This cylinder is used to print the spacer layer on a film covered with a uniform cluster layer. Through the described design of the cylinder, sharply delimited areas with defined different thicknesses of the spacing layer are obtained over the web width. A uniform aluminum mirror layer is then evaporated. The tapes with different color codes are then separated in a roll cutting process. For example, security elements with several different codes are produced in one production run. Example 5:

A security strip is cut out of a sheet of film produced as described in Example 4 in such a way that a sharp code transition comes to lie exactly in the middle of the strip. The strip produced in this way then contains, as an additional security level, two machine-readable codes which are detected individually or together with the reading device.

Example 6:

All of the layer structures described can be structured in a targeted manner using suitable lasers. In this example, an inverse layer structure was partially destroyed at the lasered areas using a 1064 nm Powerline laser from Rofin Sinar. The power was set so that the laser detaches the polymeric spacer layer from the aluminum mirror layer, so that the lasered areas no longer appear colored, but show the metallic gloss of the mirror layer. The lasering was carried out selectively. The image shown is thus composed of a dot matrix made of metallic reflecting areas in the colored area. In this way, individualized, forgery-proof markings can be made very quickly (<1sec) e.g. for ID cards.

Example 7:

For intrinsic labeling of the layers described in the previous examples, marker substances can be used which are only accessible for forensic detection. For this purpose, for example, a label of 1 per mille solid DNA can be added to the volume of the lacquer in a nitrocellulose lacquer. Under normal conditions (25 ° C, 80% humidity), the DNA adsorbs firmly onto the nitrocellulose and is so firmly anchored in the paint matrix. By dissolving the lacquer layer or by extracting with boiling water, the DNA can be extracted in the laboratory and detected using molecular biological methods. If suitable DNA sequences are used, these can also be detected on site, for example by means of a suitable hybridization assay.

Claims

claims: 1) Counterfeit-proof security feature, each consisting of at least one layer reflecting electromagnetic waves, a polymeric spacer layer and a layer formed by metallic clusters, characterized in that one or more of the layers perform additional security functions in addition to their function in the color-shift effect setup. 2) Counterfeit-proof security feature according to claim 1, characterized in that the electromagnetic wave reflecting layer and / or the cluster layer are partial layers. 3) Counterfeit-proof security feature according to one of claims 1 or 2, characterized in that the polymeric spacer layer has a defined layer thickness profile or a step structure. 4) Counterfeit-proof security feature according to one of claims 1 to 3, characterized in that the polymeric spacer layer consists of several layers, each of which can have different layer thicknesses or different layer thickness profiles. 5) Counterfeit-proof security feature according to one of claims 1 to 4, characterized in that the polymeric spacer layer consists of several partial and / or full-area layers with different refractive indices. 6) Counterfeit-proof security feature according to one of claims 1 to 5, characterized in that the polymeric spacer layer is applied in the form of characters, patterns, lines, geometric shapes and the like. 7) Counterfeit-proof security feature according to one of claims 1 to 6, characterized in that at least one layer of the polymeric spacer layer or the cover layer consists of a polymer with piezoelectric properties. 8) Counterfeit-proof security feature according to one of claims 1 to 7, characterized in that at least one layer of the polymeric spacer layer has one or more optically active structures. 9) Counterfeit-proof security feature according to one of claims 1 to 8, characterized in that the carrier substrate has a transfer lacquer layer. 10) Counterfeit-proof security feature according to one of claims 1 to 9, characterized in that the layer of metallic clusters consists of different metals. 11) Counterfeit-proof security feature according to one of claims 1 to 10, characterized in that at least one of the metallic cluster layers has additional functional features. 12) Counterfeit-proof security feature according to claim 11, characterized in that at least one of the metallic cluster layers is additionally electrically conductive and / or magnetic and / or fluorescent. 13) Counterfeit-proof security feature according to one of claims 1 to 11, characterized in that the layer structure is individualized by the action of electromagnetic waves. 14) Counterfeit-proof security feature according to claim 13, characterized in that the structure is individualized by laser treatment. 15) Counterfeit-proof security feature according to one of claims 13 or 14, characterized in that a subsequent structuring takes place by the action of electromagnetic waves. 16) Counterfeit-proof security feature according to claim 15, characterized in that images, logos, lettering, codes, characters and the like are generated by the structuring. 17) Counterfeit-proof security feature according to claim 16, characterized in that differently colored or colorless areas are achieved by the structuring. 18) Counterfeit-proof security feature according to one of claims 1 to 17, characterized in that the fine structure of the printing tool can be identified as a clearly assignable feature in the spacer layer. 19) Counterfeit-proof security feature according to one of claims 1 to 18, characterized in that the security feature is applied to a substrate or is embedded in a substrate, the substrate possibly having a recess which is spanned by the security feature. 20) Counterfeit-proof security feature according to one of claims 1 to 19, characterized in that different color-shifting effects are created by arranging a plurality of sequences of spacer layers and cluster layers which may be structured differently over a full-area or partial reflection layer. 21) Foil material suitable for producing a tamper-proof identification feature according to one of claims 1 to 20. 22) Foil material according to claim 21, characterized in that it is provided on one or both sides over the entire surface or partially with a protective lacquer layer. 23) Film material according to claim 22, characterized in that the protective lacquer layer is pigmented. 24) Foil material according to one of claims 21 to 23, characterized in that it is provided on one or both sides, over the entire surface or partially with a sealable adhesive, for example a hot or cold seal adhesive, or a self-adhesive coating. 25) Foil material according to claim 24, characterized in that the adhesive coating is pigmented. 26) Method for producing a security feature according to any one of claims 1-20, characterized in that a partial or full-surface reflecting electromagnetic waves layer on a carrier substrate and then one or more partial and / or full-surface polymer layers of a defined thickness by means of a pressure cylinder, the one has an unmistakable fine structure, on which a layer formed from metallic clusters, which are formed by means of a vacuum technology process or from solvent-based systems, is applied to the spacer layer. 27) Method according to claim 26, characterized in that a layer formed from metallic clusters on a carrier substrate be formed by means of a vacuum technology process or from solvent-based systems, then one or more partial and / or full-area polymer layers of defined, optionally varying thickness by means of a printing cylinder which contains an unmistakable fine structure, followed by a partial or full-area layer reflecting electromagnetic waves and then another Cluster layer can be applied. 28) Method according to one of claims 26 or 27, characterized in that a black background layer is additionally applied. 29) Method according to one of claims 26 to 28, characterized in that the polymeric spacer layer and / or the background layer is structured. 30) Method according to one of claims 26 to 29, characterized in that the structuring of the polymeric spacer layer or the background layer is carried out by laser treatment. 31) Use of the security features according to any one of claims 1-20 or the film materials according to one of claims 21 to 25, possibly after assembly in banknotes, data carriers, value documents, packaging, labels, labels, seals and the like. 32) Method for checking a security feature according to one of claims 1 - 20, characterized in that the different identification features are detected and identified with suitable evaluation devices. 33) Method for checking a security feature according to one of claims 1 - 20, characterized in that the identification features are visually detected and identified. 34) Method for testing security features according to one of claims 1 to 20, characterized in that the forensic features such as DNA, isotopes or fine structure are identified in the laboratory or on site with suitable test equipment.