Safety Element

Abstract

The present invention relates to a security element (1), in particular for securities, security documents or security objects such as banknotes, ID cards or credit cards, which security element (1) has at least one area (2) with an optically active diffractive structure (3), the overall impression generated by the optically active diffractive structure (3) appearing to the naked eye as being neutral.

Description

[Technical Field]

[0001] The present invention relates to a security element, in particular for securities, security documents or security objects such as banknotes, ID cards or credit cards, which has at least one area with an optically active diffractive structure. [Background technology]

[0002] Security elements of the above kind are usually used to increase the counterfeit protection of securities or security documents, such as banknotes, ID cards, credit cards, cash cards, tickets and the like.

[0003] Typically, achromatic-looking security features are represented by reflective structures based on the reflection of light due to their dimensional or structural characteristics. Such structures are often represented as micromirrors or structures with reflective facets. The resulting optical effect is often a movement effect (moving microscopic motifs) or a three-dimensional motif. Diffractive structures, on the other hand, result in the refraction of light and are therefore perceived largely as an iridescent optical effect based on their optical appearance. This includes classic holographic motifs. Furthermore, so-called diffractive moth-eye structures can be used to create security features that appear black over a wide viewing angle range and have a corresponding refracted color at flat viewing angles. These different diffractive relief structures therefore share a colorful appearance. Static motifs are often represented in this way, and in this case, it is also possible to generate a movement effect. Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to provide a security element with improved counterfeit protection. [Means for solving the problem]

[0005] The above-mentioned problem is solved by a safety element of the type mentioned at the outset, in that according to the invention the overall impression generated by the optically acting diffractive structure appears neutral to the naked eye.

[0006] The solution according to the invention allows the structure to have a neutral impression, as obtained with a reflective structure, while the diffractive properties underlying the structure can be ascertained by suitable optical measurement methods (e.g. angle-dependent optical measurements with a high-resolution microscope), thus significantly enhancing the protection against counterfeiting.

[0007] Preferably, the safety element has an image constructed from areas, in particular pixels.

[0008] It has been found to be particularly advantageous if the optically active structures are arranged irregularly, since in this case the frequency, orientation, size and / or contour of the areas in which the structures are arranged and / or the shape of the structures, e.g. the curvature of the structures, can be varied.

[0009] Furthermore, the overall impression of achromatic color can also be produced by additive color mixing of the colors generated by the structure.

[0010] According to an advantageous embodiment of the invention, the individual regions, in particular pixels, can each be formed from a plurality of optically active structures, in which case the optically active structures are oriented within the individual regions, in particular within the pixels, such that each region, in particular each pixel, appears neutral.

[0011] In a preferred variant of the invention, the structure can furthermore be covered, either completely or partially, by at least one optical effect layer.

[0012] It has proven particularly advantageous if the structure is an embossed structure, in particular a structure embossed in an embossing lacquer layer.

[0013] Particularly preferably, the optically active structures appear achromatic in plan view due to additive color mixing of the light refracted in the structures.

[0014] According to a preferred variant of the invention, the maximum extension of the areas, in particular of the pixels, respectively, can be less than the resolution limit of the human eye, in particular less than 300 μm.

[0015] According to an advantageous embodiment of the invention, the optical effect layer is formed as a thin-layer element and comprises at least one absorbing layer and at least one spacing layer.

[0016] It has been found particularly advantageous if the at least one absorber layer comprises or is made of at least one metallic material, in particular selected from the group consisting of nickel, titanium, vanadium, chromium, cobalt, palladium, iron, tungsten, molybdenum, niobium, aluminum, silver, copper and / or alloys of these materials.

[0017] At least one spacing layer may be made of, among others, aluminum oxide (Al2O3), metal fluorides, such as magnesium fluoride (MgF2), aluminum fluoride (AlF3), cerium fluoride (CeF3), sodium-aluminum fluoride (e.g., Na3AlF6 or Na5Al3F 14 ), silicon oxide (SiO x), silicon dioxide (SiO2), neodymium fluoride (NdF3), lanthanum fluoride (LaF3), samarium fluoride (SmF3), barium fluoride (BaF2), calcium fluoride (CaF2), lithium fluoride (LiF), low-refractive index organic monomers and / or low-refractive index organic polymers, or at least one low-refractive index dielectric material having a refractive index less than or equal to 1.65, selected from the group of zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO2), carbon (C), Indium oxide (In2O3), indium-zinc oxide (ITO), tantalum pentoxide (Ta2O5), cerium oxide (CeO2), yttrium oxide (Y2O3), europium oxide (Eu2O3), iron oxides such as iron(II, III) oxide (Fe3O4) and iron(III) oxide (Fe2O3), hafnium nitride (HfN), hafnium carbide (HfC), hafnium oxide (HfO2), lanthanum oxide (La2O3), magnesium oxide (MgO), neodymium oxide (Nd2O3), praseodymium oxide (Pr6O 11 It has been found particularly preferred that the dielectric layer comprises at least one high refractive index greater than 1.65 selected from the group consisting of: samarium oxide (Sm2O3), antimony trioxide (Sb2O3), silicon carbide (SiC), silicon nitride (Si3N4), silicon monoxide (SiO), selenium trioxide (Se2O3), tin oxide (SnO2), tungsten trioxide (WO3), high refractive index organic monomers and / or high refractive index organic polymers, or is made from at least one of these materials.

[0018] In a preferred embodiment, the optical effect layer formed as a thin-film element further comprises at least one reflecting layer and / or a second absorbing layer, and at least one spacing layer is arranged between the at least one first absorbing layer and the at least one reflecting layer and / or the at least one second absorbing layer.

[0019] Preferably, at least one metal selected in particular from the group of silver, copper, aluminum, gold, platinum, niobium, tin, or from the group of nickel, titanium, vanadium, chromium, cobalt and palladium, or an alloy of these materials, in particular a cobalt-nickel alloy, or, in particular, zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO2), carbon (C), indium oxide (In2O3), indium-tin oxide (ITO), pentacene (Pb ... Tantalum oxide (Ta2O5), cerium oxide (CeO2), yttrium oxide (Y2O3), europium oxide (Eu2O3), iron oxides such as iron(II, III) oxide (Fe3O4) and iron(III) oxide (Fe2O3), hafnium nitride (HfN), hafnium carbide (HfC), hafnium oxide (HfO2), lanthanum oxide (La2O3), magnesium oxide (MgO), neodymium oxide (Nd2O3), praseodymium oxide (Pr6O 11 at least one high refractive index dielectric material having a refractive index greater than 1.65 selected from the group of: silicon dioxide (SiC), samarium oxide (Sm2O3), antimony trioxide (Sb2O3), silicon carbide (SiC), silicon nitride (Si3N4), silicon monoxide (SiO), selenium trioxide (Se2O3), tin oxide (SnO2), tungsten trioxide (WO3), high refractive index organic monomers and / or high refractive index organic polymers, or made from at least one of these materials.

[0020] Furthermore, it may have a support layer made of plastic, in particular made of a light-transmitting and / or thermoplastic plastic, and preferably made of polyimide (PI), polypropylene (PP), monoaxially oriented polypropylene (MOPP), biaxially oriented polypropylene (BOPP), polyethylene (PE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polyetherketone (PEK), polyethyleneimide (PEI), polysulfone (PSU), polyacryletherketone (PAEK), polyethylene naphthalate (PEN), liquid crystal polymer (LCP), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide (PA), polycarbonate (PC), cycloolefin copolymer (COC), polyoxymethylene (POM), acrylonitrile butadiene styrene. The material may comprise or be made from at least one material from the group consisting of: (ABS), polyvinyl chloride (PVC), ethylene tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene-hexafluoropropylene-fluoro terpolymer (EFEP), cellulose or lignin-based plastics, polyhydroxyalkanoates (PHA), thermoplastic starch (TPS), polylactic acid (PLA), polycaprolactone (PCL), polybutylene succinate (PBS), and polybutylene adipate terephthalate (PBAT), and / or at least one recycled and / or biologically and / or marine degradable plastic and / or mixtures and / or copolymers of these materials.

[0021] More preferably, the safety element can be provided with a color-changing layer, in particular a color-changing pigment or liquid crystal, and / or a layer with machine-readable features, in which case the machine-readable features are in particular magnetic codes, conductive layers, substances that absorb and / or re-emit electromagnetic waves. In particular, the safety element can have additional layers, in particular protective lacquers, heat-sealing lacquers, adhesives, primers and / or films.

[0022] For a better understanding of the present invention, the invention will now be described in detail with reference to the following figures.

[0023] The figure is a highly simplified diagrammatic representation. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 shows the layer structure of a safety element according to the invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] According to Fig. 1, a security element 1 according to the invention, such as that used for the prevention of counterfeiting of securities, security documents or security objects, such as banknotes, ID cards, credit cards, tickets, etc., has an area 2 in which structures 3 are arranged. This area 2 may extend over a portion of the security element 1 or over the entire security element 1. The optically active structures 3 of the area 2 form areas of the image, in particular pixels. In the following description, for ease of reading, only the notion of pixel will be used representatively instead of the notions of area or pixel. Several structures 3 can form one pixel.

[0026] The image formed from the pixels may represent or have a motif, for example a portrait, a landscape, an abstract geometric symbol, a logo or a sequence of alphanumeric symbols and / or icons and / or codes and / or symbols.

[0027] The maximum extension of a pixel is preferably between 0.5 μm and 100 μm.

[0028] The structure 3 is a light-refracting or diffractive structure. By means of a diffractive structure, for example, a hologram, a moving image or a static image can be realized. The overall impression generated by the optically active structure 3 appears to the naked eye as achromatic.

[0029] The underlying diffractive properties of structure 3 are visible only within a very narrow angle, which depends on the grating spacing but does not negatively affect the overall impression of achromatic color, or can be determined by suitable optical measurement methods (e.g., angle-dependent optical measurements with a high-resolution microscope).

[0030] The structure 3 can, for example, generate a hologram and can have a depth T of, for example, greater than 500 nm, in particular between 500 nm and 4 μm. In this context, the depth T of the structure 3 is the vertical distance between the level of the lowest point of the structure 3 and the level of the highest point. In this case, the width B of the structure 3 corresponds to the minimum width of the depth of the structure 3. Preferably, the structure 3 has an aspect ratio of 0.05 to 8. For structures with a right-angle inclination angle, for example, a columnar structure, the aspect ratio is the ratio of the depth T to the width B of the structure 3. For structures with an inclination angle different from 90°, for example, a sawtooth structure, the aspect ratio represents the ratio of the depth T to the peak-to-peak distance of the structure.

[0031] To display achromatic appearing motifs with diffractive optically acting structures 3, there are several options.

[0032] The individual structures 3 can be configured, for example, so that the refracted colors generated in that case overlap by additive color mixing at an observer (at a distance from the safety element itself) and have the appearance of white, resulting in an overall approximately achromatic behavior.

[0033] Each individual pixel can have a different colored appearance under a wide viewing area. By combining pixels with different arrangements of optically interacting diffractive structures, the colors of each individual pixel can be distinguished. Overall, the additive color mixing results in a neutral appearance.

[0034] Alternatively or additionally, various diffractive structures 3 can be present within one pixel, so that an additive color mixture already occurs within the pixel, and both the pixel and the entire motif appear achromatic.

[0035] In addition to or instead of additive color mixing, the impression of achromatic color of the diffractive structures can also be achieved, for example, by randomly arranging the structures. In this case, it is not necessary to intentionally arrange the diffractive structures within the arranged pixels. The area 2 can be filled by a free-form arrangement of the diffractive structures 3. In this way, the irregularity suppresses the diffraction effect. In this connection, it is particularly effective if the structures are substantially randomly distributed, in which case it is possible to vary, in particular, the frequency, arrangement, size and / or contour of the areas in which the structures are arranged, and / or the shape of the structures, for example, the curvature of the structures.

[0036] To calculate the geometry of the structure, software can be used, which for example determines the geometry of the optically acting structure 3 using the boundary conditions listed above.

[0037] The neutral appearance of the optically active structure 3 substantially increases the security against counterfeiting, even in the absence of additional optical effect layers, since, as already mentioned above, the diffractive properties of the structure are only visible under very specific viewing angles or can only be recognized / measured with appropriate optical aids.

[0038] It is also possible to make only a portion of a motif (static or dynamic) to be displayed achromatic, while other portions have a colored appearance (based on a diffractive structure), for example, so that the colored portions can be displayed within the otherwise achromatic motif (or vice versa) as intended.

[0039] On the structure 3 an optical effect layer 4 can be provided, either completely or partially.

[0040] For example, the effect layer 4 may be provided with recessed regions 5. The optical effect layer 4 may be arranged directly on the structure 3. However, an additional adhesive layer may also be arranged between the structure 3 and the optical effect layer 4. The material of the adhesive layer may be selected from the group consisting of, for example, nickel, titanium, manganese, vanadium, chromium, cobalt, palladium, iron, tungsten, molybdenum, niobium, aluminum, silver, copper and / or alloys of these materials, in particular at least one nickel-chromium alloy comprising or formed from at least one of these materials. Particularly preferably, the material of the adhesive layer is chromium or a nickel-chromium alloy, such as, for example, Inconel.

[0041] The optical effect layer 4 is preferably formed as a thin layer element and has at least one absorbing layer 6 and at least one spacing layer 7.

[0042] The absorber layer 6 may comprise or be made of at least one metallic material selected from the group of nickel, titanium, vanadium, chromium, cobalt, palladium, iron, tungsten, molybdenum, niobium, aluminum, silver, copper, and / or alloys of these materials.

[0043] The at least one spacing layer 7 can be made of, for example, a dielectric material. Furthermore, the at least one spacing layer 7 can be made of, in particular, aluminum oxide (Al2O3), metal fluorides, such as magnesium fluoride (MgF2), aluminum fluoride (AlF3), cerium fluoride (CeF3), sodium aluminum fluoride (e.g., Na3AlF6 or Na5Al3F 14 ), silicon oxide (SiO x At least one low refractive index dielectric material having a refractive index less than or equal to 1.65 selected from the group consisting of silicon dioxide (SiO2), neodymium fluoride (NdF3), lanthanum fluoride (LaF3), samarium fluoride (SmF3), barium fluoride (BaF2), calcium fluoride (CaF2), lithium fluoride (LiF), low refractive index organic monomers and / or low refractive index organic polymers, or zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO2), carbon (C), iodo (InO2), Indium (In2O3), indium-zinc oxide (ITO), tantalum pentoxide (Ta2O5), cerium oxide (CeO2), yttrium oxide (Y2O3), europium oxide (Eu2O3), iron oxides such as iron(II, III) oxide (Fe3O4) and iron(III) oxide (Fe2O3), hafnium nitride (HfN), hafnium carbide (HfC), hafnium oxide (HfO2), lanthanum oxide (La2O3), magnesium oxide (MgO), neodymium oxide (Nd2O3), praseodymium oxide (Pr6O 11 ), samarium oxide (Sm2O3), antimony trioxide (Sb2O3), silicon carbide (SiC), silicon nitride (Si3N4), silicon monoxide (SiO), selenium trioxide (Se2O3), tin oxide (SnO2), tungsten trioxide (WO3), high refractive index organic monomers and / or high refractive index organic polymers, or can be made from at least one of these materials.

[0044] The optical effect layer 4 formed as a thin layer element can be applied directly onto the structure 3 or onto the above-mentioned adhesive layer, which can be arranged on the structure 3, for example.

[0045] The thicknesses of the layers forming the thin layer elements are shown greatly exaggerated and not to scale.

[0046] The color-changing optical effect layer 4 may further comprise a reflective layer 8. In that case, at least one spacing layer 7 is arranged between the absorbing layer 6 and the reflective layer 8. The reflective layer 8 is provided on the structure 3 and may in particular be painted and / or vapor-deposited thereon. It is also possible to reverse this order within the optical effect layer, so that the absorbing layer is on the adhesive layer or on the structure 3, followed by the spacing layer and the reflective layer. Thus, the arrangement according to this order is: structure 3 - absorbing layer 6 - spacing layer 7 - reflective layer 8.

[0047] The reflective layer 8 is made of a metallic material, in particular selected from the group of silver, copper, aluminum, gold, platinum, niobium, tin, or from the group of nickel, titanium, vanadium, chromium, cobalt and palladium, or from alloys of these metals, in particular cobalt-nickel alloys, or a metal such as zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO2), carbon (C), indium oxide (In2O3), indium-tin oxide (ITO), pentacene (PTFE), palladium nitrate (PTA ... Tantalum oxide (Ta2O5), cerium oxide (CeO2), yttrium oxide (Y2O3), europium oxide (Eu2O3), iron oxides such as iron(II, III) oxide (Fe3O4) and iron(III) oxide (Fe2O3), hafnium nitride (HfN), hafnium carbide (HfC), hafnium oxide (HfO2), lanthanum oxide (La2O3), magnesium oxide (MgO), neodymium oxide (Nd2O3), praseodymium oxide (Pr6O 11), samarium oxide (SmO), antimony trioxide (SbO), silicon carbide (SiC), silicon nitride (SiN), silicon monoxide (SiO), selenium trioxide (SeO), tin oxide (SnO), tungsten trioxide (WO), high refractive index organic monomers and / or high refractive index organic polymers, or can be made of at least one of these materials. This applies to all reflective layers 8 described in the examples.

[0048] However, instead of the reflective layer 8 mentioned above, other absorbing layers may also be provided.

[0049] The safety element 1 may further comprise a support layer 9. This support layer 9 may be made of a plastic material. Furthermore, the support layer 9 may be made of several layers. This plastic may be made of a light-transmitting and / or thermoplastic plastic material. Examples of materials for the support layer 9 include polyimide (PI), polypropylene (PP), uniaxially oriented polypropylene (MOPP), biaxially oriented polypropylene (BOPP), polyethylene (PE), polyphenylene sulfide (PPS), polyether ether ketone (PEEK), polyether ketone (PEK), polyethyleneimide (PEI), polysulfone (PSU), polyacryl ether ketone (PAEK), polyethylene naphthalate (PEN), liquid crystal polymer (LCP), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide (PA), polycarbonate (PC), cycloolefin copolymer (COC), polyoxymethylene (POM), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), and ethylene tetrafluoroethylene (ETF). The support layer may comprise or be made of at least one material from the group consisting of: ethylene (FE), polytetrafluoroethylene (PTFE), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene-hexafluoropropylene-fluoro terpolymer (EFEP), cellulose- or lignin-based plastics, polyhydroxyalkanoates (PHAs), thermoplastic starch (TPS), polylactic acid (PLA), polycaprolactone (PCL), polybutylene succinate (PBS), and polybutylene adipate terephthalate (PBAT), and / or at least one recycled and / or biologically and / or marine-degradable plastic and / or mixtures and / or copolymers of these materials. In this case, the support layer may have a thickness of 5 μm to 1000 μm, particularly preferably 10 μm to 50 μm.

[0050] The optical effect layer 4 may be disposed or applied onto the structure 3 by, for example, a printing process and / or a vapor deposition process, or a combination thereof.

[0051] In this context, although the optical effect layer 4 is described as a thin layer element, the optical effect layer 4 can also be realized, for example, in combination with an ink or printing ink containing a color-changing pigment, a lacquer containing a color-changing pigment or a liquid crystal layer, in particular a dark overcoat layer provided on the side opposite the visible surface of the liquid crystal layer.

[0052] The structure 3 can be embossed directly into the support layer 9. For example, this can be done by heating the support layer 9 and embossing the structure using an embossing tool such as an embossing roller.

[0053] Another alternative option consists in providing a further layer 10 dedicated to accommodating the structures 3. The further layer 10 can be provided directly on the support layer 9. For example, the further layer 10 can be formed by an embossing lacquer, suitably formed for arranging the structures 3. This can also be done by using a patterning device or patterning element in the embossing process. This further layer, in particular the embossing lacquer layer, together with the structures 3 formed therein can have a thickness of, for example, 0.5 μm to 300 μm, in particular 0.8 μm to 50 μm, preferably 1 μm to 10 μm.

[0054] Furthermore, an intermediate layer may be provided between layer 10 and support layer 9, and the intermediate layer may be formed of, for example, an adhesive, a primer, or an adhesive.

[0055] As a top or outermost layer of the optical effect layer 4, for example, a protective layer (not shown here) can be provided, which protects the layer structure and / or the entire layer structure from mechanical damage, for example, scratches, grooves, etc. This protective layer can be arranged on the side of the support layer 9 opposite the optical effect layer, or even on both sides. Preferably, this protective layer can also be used to form the safety element 1 in a planar form.

[0056] It should be noted that the layer structure and the arrangement of the other layers depend on the method of attaching the safety element to the safety object, since the side of the safety element to be viewed is determined after attachment. Thus, as shown in the figures, the viewing side can be considered to be from above, but it is also possible to consider the safety element as being viewed from below, for example through a support.

[0057] It should be noted here that the expression "providing a layer on something" means that the layer can be directly provided, or that one or more intermediate layers exist between the provided layer and the layer below it. It should also be noted here that one or more intermediate layers can be disposed between the layers described in this document. Therefore, it is not necessary for the described layers to be in contact with each other. Furthermore, it should be noted that in this specification, the concept of a layer means that one layer can be constructed from multiple sub-layers.

[0058] Furthermore, the entire layer structure of the safety element can be attached to or in the object to be protected, or it can be formed as a transfer element in which at least one security feature formed from the diffractive structure, possibly together with other layers, is transferred onto the object to be protected and then peeled off from the transfer film. [Explanation of symbols]

[0059] 1 Safety Element 2 areas 3. Structure 4 Effect Layer 5 areas 6 Absorbing layer 7 Spacing Layer 8 reflective layer 9 Support layer 10 layers

Claims

1. A security element (1) for securities, security documents or security objects, in particular banknotes, ID cards, credit cards, said security element (1) having at least one area (2) with an optically active diffractive structure (3), A safety element characterized in that the overall impression generated by said optically acting diffractive structure (3) appears achromatic to the naked eye.

2. 2. A safety element according to claim 1, characterized in that the safety element (1) has an image constructed from areas, in particular pixels.

3. 3. A safety element according to claim 1 or 2, characterized in that the optically active structures are arranged irregularly, preferably substantially randomly, and in particular the frequency, the orientation, the size and / or the contour of the area in which they are arranged and / or the shape of the structures, e.g. the curvature of the structures, vary.

4. 4. A safety element according to any one of claims 1 to 3, characterized in that the overall impression of achromatic colour is produced by an additive colour mixture of the colours generated by the structure.

5. 5. A safety element according to claim 2, wherein the individual regions, in particular pixels, are each formed from a plurality of optically active structures, the optically active structures being oriented within the individual regions, in particular pixels, in such a way that each region, in particular each pixel, appears neutral.

6. 6. Safety element according to any one of claims 1 to 5, characterized in that the structure (3) is covered, totally or partly, by at least one optical effect layer (4).

7. 7. Safety element according to any one of claims 1 to 6, characterized in that the structure (3) is an embossed structure, in particular a structure embossed into an embossing lacquer layer.

8. 8. A safety element according to claim 1, wherein the optical effect layer (4) is formed as a thin-layer element and comprises at least one absorbing layer (6) and at least one spacing layer (7).

9. 9. A safety element according to claim 8, characterized in that at least one said absorber layer (6) comprises or is made of at least one metallic material, in particular selected from the group of nickel, titanium, vanadium, chromium, cobalt, palladium, iron, tungsten, molybdenum, niobium, aluminium, silver, copper and / or alloys of these materials.

10. At least one of said spacing layers (7) is in particular made of aluminum oxide (Al ２ O ３ ), metal fluorides, for example, magnesium fluoride (MgF ２ ), aluminum fluoride (AlF ３ ), cerium fluoride (CeF ３ ), sodium aluminum fluoride (e.g., Na ３ AlF ６ or Na ５ Al ３ F １４ ), silicon oxide (SiO ｘ ), silicon dioxide (SiO ２ ), neodymium fluoride (NdF ３ ), lanthanum fluoride (LaF ３ ), samarium fluoride (SmF ３ ), barium fluoride (BaF ２ ), calcium fluoride (CaF ２ ), lithium fluoride (LiF), at least one low refractive index dielectric material having a refractive index less than or equal to 1.65, selected from the group of low refractive index organic monomers and / or low refractive index organic polymers, or, in particular, zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO ２ ), carbon (C), indium oxide (In ２ O ３ ), indium zinc oxide (ITO), tantalum pentoxide (Ta ２ O ５ ), cerium oxide (CeO ２ ), yttrium oxide (Y ２ O ３ ), europium oxide (Eu ２ O ３ ), for example, iron (II, III) oxide (Fe ３ O ４ ) and iron(III) oxide (Fe ２ O ３ ), hafnium nitride (HfN), hafnium carbide (HfC), hafnium oxide (HfO ２ ), lanthanum oxide (La ２ O ３ ), magnesium oxide (MgO), neodymium oxide (Nd ２ O ３ ), praseodymium oxide (Pr ６ O １１ ), samarium oxide (Sm ２ O ３ ), antimony trioxide (Sb ２ O ３ ), silicon carbide (SiC), silicon nitride (Si ３ N ４ ), silicon monoxide (SiO), selenium trioxide (Se ２ O ３ ), tin oxide (SnO ２ ), tungsten trioxide (WO ３ 10. A safety element according to claim 8 or claim 9, characterized in that it comprises or is made of at least one high refractive index dielectric material having a refractive index greater than 1.65, selected from the group of: highly refractive organic monomers and / or highly refractive organic polymers.

11. 11. A safety element according to claim 8, wherein the optical effect layer (4) formed as a thin-layer element further comprises at least one reflecting layer (8) and / or a second absorbing layer, and wherein at least one spacing layer (7) is arranged between the at least one first absorbing layer (6) and the at least one reflecting layer (8) and / or the at least one second absorbing layer.

12. The at least one reflective layer (8) is made of at least one metallic material, in particular selected from the group of silver, copper, aluminum, gold, platinum, niobium, tin, or from the group of nickel, titanium, vanadium, chromium, cobalt and palladium, or from alloys of these materials, in particular cobalt-nickel alloys, or from metals such as zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO ２ ), carbon (C), indium oxide (In ２ O ３ ), indium tin oxide (ITO), tantalum pentoxide (Ta ２ O ５ ), cerium oxide (CeO ２ ), yttrium oxide (Y ２ O ３ ), europium oxide (Eu ２ O ３ ), for example, iron (II, III) oxide (Fe ３ O ４ ) and iron(III) oxide (Fe ２ O ３ ), hafnium nitride (HfN), hafnium carbide (HfC), hafnium oxide (HfO ２ ), lanthanum oxide (La ２ O ３ ), magnesium oxide (MgO), neodymium oxide (Nd ２ O ３ ), praseodymium oxide (Pr ６ O １１ ), samarium oxide (Sm ２ O ３ ), antimony trioxide (Sb ２ O ３ ), silicon carbide (SiC), silicon nitride (Si ３ N ４ ), silicon monoxide (SiO), selenium trioxide (Se ２ O ３ ), tin oxide (SnO ２ ), tungsten trioxide (WO ３ 12. A safety element according to claim 11, characterized in that it comprises or is made of at least one highly refractive dielectric material having a refractive index greater than 1.65, selected from the group of: highly refractive organic monomers and / or highly refractive organic polymers.

13. a support layer (9) made of plastic, in particular made of a translucent plastic and / or a thermoplastic plastic, and The support layer is preferably made of polyimide (PI), polypropylene (PP), uniaxially oriented polypropylene (MOPP), biaxially oriented polypropylene (BOPP), polyethylene (PE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polyetherketone (PEK), polyethyleneimide (PEI), polysulfone (PSU), polyacryletherketone (PAEK), polyethylene naphthalate (PEN), liquid crystal polymer (LCP), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide (PA), polycarbonate (PC), cycloolefin copolymer (COC), polyoxymethylene (POM), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), ethylene tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), polyisoprene ...

13. A safety element according to any one of claims 1 to 12, characterized in that it comprises or is made from at least one material from the group consisting of ethylene (PTFE), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene-hexafluoropropylene-fluoro terpolymer (EFEP), cellulose or lignin-based plastics, polyhydroxyalkanoates (PHA), thermoplastic starch (TPS), polylactic acid (PLA), polycaprolactone (PCL), polybutylene succinate (PBS), and polybutylene adipate terephthalate (PBAT), and / or at least one recycled and / or biologically and / or marine degradable plastic and / or mixtures and / or copolymers of these materials.

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