Security element with relief structure

Abstract

The invention relates to a security element (1) comprising a support substrate (2) and a relief structure (3) that is provided thereon and displays, in incident light, at least one motif which is based on the viewing angle or which is not based on the viewing angle, wherein the relief structure (3) has structure-forming three-dimensional elements (4), which are formed by means of a free-form surface, and is divided into a plurality of segments (5) with defined optical properties, by virtue of which the motif appears in a first color (7) at a first viewing angle (6) and in a second color (9) at a second viewing angle (8); in at least one region (10) of the segments (5), the structure-forming elements (4) are designed to vary from the other structure-forming elements (4) in terms of the structural properties thereof in such a way that the motif appears in at least one third color (12) in a viewing range (11) outside the first viewing angle (6) and the second viewing angle (8) as a result of the influence of the coating (14) by means of the changed structural properties of the structure-forming elements in said region (10).

Description

[0001] SAFETY ELEMENT WITH RELIEF STRUCTURE

[0002] The invention relates to a security element, in particular for securities, security paper or security items such as banknotes, identity cards, credit cards, with at least one viewing angle-dependent impression, comprising a planar carrier substrate and at least one relief structure, wherein the relief structure represents at least one viewing angle-dependent or viewing angle-independent motif in reflected light and the relief structure has structure-forming three-dimensional elements.

[0003] Security elements of the type mentioned above are used to protect against counterfeiting of securities, such as banknotes, tickets, etc., security papers and security documents, such as identity cards.

[0004] In E P1506096 B1, an optically variable element with sub-surfaces having achromatic surface structures and different scattering, diffraction, and reflection characteristics is described, which are combined with a thin-film structure, resulting in a defined, almost discrete color change for the viewer when rotating.

[0005] The object of the present invention is to create a security element with increased protection against counterfeiting.

[0006] It should be noted here that, in the context of the invention, the term "safety element" can refer to various types of safety elements familiar to those skilled in the art. For example, safety elements can be designed as safety threads, safety strips, safety patches, and the like. Of course, other types of safety elements known to those skilled in the art are also conceivable.

[0007] This task is solved by a safety element according to the requirements.

[0008] This task is solved by a safety element of the type mentioned above, in which the relief structure has structure-forming three-dimensional elements formed by means of a freeform surface (or freeform optics) that exhibits at least partial irregularities with respect to its optical properties, wherein the relief structure is provided with at least one coating that produces an optically variable effect, and the relief structure is divided into several segments with defined optical properties, by means of which the motif appears in a first color at a first viewing angle and in a second color at a second viewing angle, and is characterized by the fact that in at least one area of ​​individual segments the structure-forming elements are designed to vary with respect to their structural properties compared to the other structure-forming elements, such that by influencing the,A coating that produces an optically variable effect by means of varying structural properties of the structure-forming elements in the area where the motif appears in at least a third color in a further viewing area outside the first and second viewing angles.

[0009] The solution according to the invention increases counterfeit protection by forming the relief structure using a freeform surface that features a color-shifting effect (at least between the first and second viewing angles), which, in addition to the two colors of the color-shifting effect, also exhibits a further color. With the solution according to the invention, an optical appearance can be achieved that is unique, characteristic, and easily recognizable to an observer, but extremely difficult for a counterfeiter to imitate.

[0010] The defined optical properties of the segments include, in particular, ray-optical properties, especially selected from the group; specular reflection, diffuse reflection, refraction, focusing, divergence, and, if applicable, wave-optical properties, such as diffraction.

[0011] Since the relief structure is formed by means of a freeform surface or freeform optics and is divided into segments of defined optical properties, it is highly complex, which makes it considerably more difficult to imitate.

[0012] Optical freeform surfaces allow light striking the relief structures to be directed in any direction and can be optimally aligned with the respective motif being depicted. A combination with a color-shifting effect, which includes at least one additional third color, makes the appearance distinctive and therefore difficult to imitate.

[0013] In particular, the freeform surface allows for the incorporation of further security criteria based on optical irregularities in the structures, which are especially difficult to imitate. Regarding these "irregularities," it should be noted that they are designed as a component of the freeform surface, which, with respect to the structure-forming elements, can form individual, irregularly oriented areas, but are nevertheless included or categorized within segments of defined optical properties.

[0014] For the sake of completeness, it should be mentioned at the outset that the first, second, and at least third colors are distinct from one another. Preferably, these colors are clearly distinguishable to the naked eye and thus not merely minor variations of the same color impression. A possible color combination would be, for example, green and magenta as the first and second colors, and blue as at least the third color.

[0015] Based on the structural properties of the existing segments, the overall impression of a viewed area or motif appears in different colors depending on the viewing angle. By means of the additionally modified segments or their structure-forming elements according to the invention, the coating, which produces an optically variable effect, is further influenced in such a way that outside the first and second viewing angles, the respective visible color (first color or second color) is transformed in a color transition into at least one further color, so that the third color appears.

[0016] In this regard, the structural properties of the structural elements of selected segments are specifically modified in certain areas in order to deliberately manipulate the interference properties associated with the coating, which produces an optically variable effect.

[0017] The structural properties can include at least one of the following;

[0018] - Grating constant (for optical gratings)

[0019] - Depth of structures

[0020] - Angle of inclination (or slope)

[0021] - Orientation (or alignment)

[0022] - Size of the structure-forming elements (e.g., a projected area in top view).

[0023] The structural properties can therefore preferably be geometric properties or variables of the structure-forming elements, by means of which the altered optical properties can be achieved. In particular, an optically (effective) thickness (of the freeform surface) can be changed or adjusted by the (varying) structural properties, which, depending on the viewing angle, causes the motif to appear in a different color impression by influencing the coating.

[0024] For example, the angle of inclination and / or the orientation of individual structures can be changed so that, at a viewing angle within the viewing area, they influence the aforementioned optical properties, and, for example, a change in the optical beam path in a segment with the altered structural properties can take place – only within the viewing area – and outside the viewing area, the segments relative to each other (depending on the viewing angle) cause the motif to appear in the first and second colors.

[0025] Likewise or additionally, the depth (as well as the other mentioned properties) of the elements, which vary in their structural properties, can be chosen in such a way that the coating, which produces an optically variable effect, only influences the optical properties in the viewing area.

[0026] In principle, an interference condition for the viewing area can be provided or determined, e.g. by simulation, based on which the structural properties to be adapted (depending on the existing optical properties of the other, unchanged segments) of the structure-forming elements of the selected segments to be changed are derived or calculated - and are accordingly incorporated into the relief structure in certain areas.

[0027] Thus, in the manufacturing process of the freeform surface—which forms the relief structure—the selected area of ​​the segments is adjusted by selectively adjusting these different variables relative to each other. The coating, which creates an optically variable effect and generates the color impression under the first and / or second viewing angle, can, under the influence of the adjusted area (of segments) within the viewing field, cause the other color to appear.

[0028] This color transition can preferably also be continuous, so that each of the individual colors is present proportionally in the viewing area, depending on the current viewing angle, and increases or decreases when the angle changes (in the direction of the first or second viewing angle).

[0029] A thin-film structure can be arranged on the relief structure as a particularly preferred optical effect layer, which will be discussed later.

[0030] For the production of relief structures, master structures are often transferred into a polymer using an embossing process – as is generally known, this often involves multiple replications of the master. By dividing the relief structures into segments with defined optical properties, it is possible to achieve a flawless, or at least nearly flawless, replication of master structures with freeform surfaces. The segments contain the desired information of the corresponding freeform surface. This segmentation reduces the complexity of the structures without compromising their optical properties. This facilitates the molding of the structures into polymer layers, such as UV coatings or thermoformable polymers, for example, into the substrate.

[0031] The segmentation itself leads to area-specific defined optical conditions, which in turn results in higher light yield and thus enables more contrast-rich representations.

[0032] By using the freeform optics via the freeform surface, far more complex optical patterns can be generated compared to simpler optical elements such as micromirrors, lenses, prisms, etc., since a wide variety of ray-optical processes such as directed reflection, diffuse reflection, refraction, focusing, divergence, as well as wave-optical processes such as diffraction, can be realized in the smallest space.

[0033] The motif can be a portrait, a landscape, an abstract geometric symbol, a logo, an alphanumeric symbol, an icon, a code, and / or a sequence of characters.

[0034] In the context of the invention, the term "segment" refers to the sum of the elements it contains and can comprise a single element or multiple elements. A structure-forming element is the smallest optically effective unit. Regarding the arrangement of the elements with their varying structural properties, it can be provided that the viewing area lies between the first and second viewing angles. By means of such a configuration, the motif in the additional third color can be made recognizable when viewing the security element between the first and second viewing angles, thereby further increasing counterfeit protection.

[0035] Alternatively, it can also be provided that the second viewing angle lies between the first viewing angle and the viewing area. It can also be provided that the motif in the additional color only becomes visible in a subsequent viewing area when tilted, by appearing after the first and second viewing angles when viewed from a particular direction.

[0036] Preferably, the first viewing angle may be in a range of 85° to 95°, in particular 90°, with respect to a surface plane of the safety element.

[0037] Furthermore, the second viewing angle or viewing area can be in a range of 30° to 1° with respect to the surface plane of the safety element.

[0038] Considering the first and second viewing angles (or viewing range), the viewing range (or the second viewing angle) can, for example, lie between 30° and 85°.

[0039] It may be particularly advantageous to provide that the third color and at least the first color appear between a central section of the viewing area and the first viewing angle (preferably section by section or partially). In this regard, it may be provided that the elements, which vary in their structural properties, in the affected sub-area of ​​the viewing area, for example at a fourth viewing angle, only partially influence the coating that produces an optically variable effect, so that the first and third colors are visible.

[0040] In general, a "middle section" is understood to mean a middle area with respect to a viewing angle range when considering the safety element.

[0041] Additionally or alternatively, the third color and at least the second color can also appear (partially or in sections) between the central section of the viewing area and the second viewing angle. In this regard, analogous to the previous variant, it can be provided that the elements with varying structural properties in the affected sub-area of ​​the viewing area, for example, at a fifth viewing angle, only partially influence the coating that produces an optically variable effect, so that the second and third colors are visible.

[0042] The structure-forming elements of the area can be designed with such properties that they partially influence the coating for generating the additional color in the viewing area, so that the first color (between the middle section and the first viewing angle) or the second color (between the middle section and the second viewing angle) is still recognizable in sections.

[0043] According to the further explanation, in which the second viewing angle lies between the first viewing angle and the viewing area, it can also be provided that the first and second colors appear between the (at least middle section of the) viewing area(s) and the first and second viewing angles.

[0044] An additional interplay of at least two colors in the viewing area can create a particularly unique, characteristic and recognizable impression of a security element.

[0045] Furthermore, the structural elements of the area can be designed such that, within the viewing area, they influence the coating, which produces an optically variable effect, differently depending on the viewing angle, so that the proportion of the respective colors decreases or increases. For example, it can be provided that as the viewing angle moves from the viewing area towards the second viewing angle, the proportion of the second color increases (and the proportion of the third color decreases).

[0046] Furthermore, according to one possible embodiment, it can also be provided that in the central section of the viewing area, the first, second, and at least third colors are recognizable at a certain viewing angle. A further possible embodiment provides that along a direction in a surface plane of the safety element, the segments with elements varying in their structural properties are arranged in a repeating pattern such that the third color and at least one of the colors comprising the first and second colors appear alternately and repeatedly along that direction (when viewed in the viewing area). The repeating arrangement can be regular or irregular.

[0047] Furthermore, according to one embodiment, it can be provided that a color shift effect between the first and second color is maintained in such a way that an acute color change (with the exception of the third color) between the first and second color can take place.

[0048] According to an alternative embodiment, it is also conceivable that at least one of the colors, comprising the first color and the second color, does not appear in the entire viewing area, so that by influencing the coating which produces an optically variable effect through the segments, only the at least third color is visible in at least one part or section of the viewing area.

[0049] Furthermore, by combining the optical properties of the segments with the coating, which creates an optically variable effect, the motif can appear in only the third color across the entire viewing area. Such a design can, for example, create a three-color shift effect, resulting in a particularly distinctive impression.

[0050] The coating that produces an optically variable effect can also be a reflective coating.

[0051] An "optically variable effect" refers to a property of the coating that presents at least two different perceptible impressions to the eye from different viewing angles, particularly, for example, color shift effects. These optically variable effects can be adjusted and modified in specific areas in combination with the relief structure.

[0052] The relief structure can be at least partially coated, allowing the coating to be omitted in certain areas. This further increases counterfeit protection. Alternatively, the relief structure can also be fully coated.

[0053] It is particularly advantageous to provide that the coating, which produces an optically variable effect, creates a viewing-angle-dependent impression of the motif. This further increases counterfeit protection. The viewing-angle-dependent color impression changes or is adapted to the viewing-angle-dependent motif. This further increases the contrast and thus the recognizability and counterfeit protection.

[0054] According to further training, the coating may be designed as a color-shifting layer or comprise a color-shifting layer. This further increases counterfeit protection.

[0055] Preferably, the coating may be formed by an optical thin-film element in the form of an interference element. This further increases the counterfeit protection.

[0056] In a further embodiment, it may be provided that the coating contains color-shifting pigments, in particular interference pigments, or liquid crystal pigments, or that the coating contains metallic pigments and / or magnetic pigments and / or color pigments and / or dyes.

[0057] It is also conceivable that the coating has at least one layer on a side facing away from a visible side that reinforces the color shift effect.

[0058] Furthermore, it is possible that sub-areas of at least some of the segments of the relief structure differ from one another, at least in their average coating thickness. Here, average coating thickness refers to the average thickness across a segment. This further increases counterfeit protection. Preferably, the average coating thickness in the areas with the varying elements differs from that in the other segments.

[0059] Effect coatings, such as color-shifting thin-film elements, exhibit their optical effect depending on the average layer thickness used. In the case of freeform surfaces, the average layer thickness can vary depending on the vapor deposition process and the geometry of the structures. Segmentation allows the structures within the segments to be designed in such a way that the change in layer thickness can be taken into account, resulting in an average layer thickness that is favorable for achieving the desired effect.

[0060] A particularly advantageous embodiment provides that the optical effect layer or coating is designed as a thin-film element and has at least one absorber layer and at least one spacer layer.

[0061] A possible structure of a thin-film element can have the following layer sequence: relief structure - spacer layer - absorber layer or relief structure - absorber layer - spacer layer.

[0062] Furthermore, the optical effect layer or coating, which is designed as a thin-film element, can also include at least one reflection layer, wherein the at least one spacer layer is arranged between the at least one absorber layer and the at least one reflection layer.

[0063] A possible structure of a thin-film element can have the following layer sequence: relief structure - reflection layer - spacer layer - absorber layer or relief structure - absorber layer - spacer layer - reflection layer. Another design involves applying the reflection layer to the relief structures, in particular by printing and / or vapor deposition.

[0064] Furthermore, it can be advantageous if the coating that creates an optical effect is printed and / or vapor-deposited onto the relief structures.

[0065] Another embodiment is characterized in that the coating producing an optical effect has at least one liquid crystal layer, in particular a cholesterol liquid crystal layer.

[0066] Another preferred embodiment provides that, in addition to the coating producing an optical effect, the security element includes an optically non-linear layer or layer and / or a layer containing fluorescent pigments and / or fluorescent substances. Optically non-linear layers or layers, or the materials forming these layers, are also referred to as IR upconverters or UV downconverters. These materials can exhibit a visible color under the influence of electromagnetic radiation outside the visible wavelength range of light. Such materials can be excited to emit visible light under these conditions, for example, when irradiated with infrared (IR) (X > 780 nm) and / or ultraviolet (UV) light (< 380 nm).Furthermore, it is possible that the optical effect layer and / or additional layers contain photoluminescent pigments and / or photoluminescent substances which exhibit emission in the IR range when excited with electromagnetic radiation.

[0067] Furthermore, a strongly absorbing dielectric material, such as germanium, can be used as an additional layer. This additional layer can, for example, be applied to the color-shifting optical effect layer, which can be designed in the form of a thin-film element.

[0068] One possible embodiment is characterized by the fact that several structure-forming elements and / or segments are arranged in such a way that the arrangement of the structures forms several individual symbols, which symbols are contained in the image. This offers a further advantage, as this design incorporates an additional security feature.

[0069] It may also be advantageous for the security element to be equipped with further color-changing layers, in particular layers with color-changing pigments or liquid crystals and / or with machine-readable features, wherein the machine-readable features are in particular magnetic codings, electrically conductive layers, electromagnetic wave-absorbing and / or re-emitting substances.

[0070] Another possible and, if applicable, alternative embodiment has the features that the security element has further or additional layers, which additional layers include in particular protective coatings, heat-seal coatings, adhesives, primers and / or films.

[0071] A preferred embodiment provides that the safety element comprises a support substrate or a support layer made of a plastic, wherein the plastic is in particular made of a translucent and / or thermoplastic plastic, and that the support layer preferably comprises at least one of the materials from the group consisting 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), polyaryletherketone (PAEK), polyethylene naphthalate (PEN), liquid crystalline polymers (LCP), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide (PA), polycarbonate (PC), cycloolefin copolymers (COC), polyoxymethylene (POM), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), and ethylene tetrafluoroethylene (ETFE). Polytetrafluoroethylene (PTFE), polyvinyl fluoride (PVF),Polyvinylidene fluoride (PVDF), ethylene tetrafluoroethylene hexafluoropropylene fluoropolymer (EFEP), cellulose- or lignin-based plastics, polyhydroxyal canoates (PHA), thermoplastic starch (TPS), polylactic acid (PLA), polycaprolactone (PCL), polybutylene succinate (PBS), and polybutylene adipate rephthalate (PBAT) and / or at least one recycled and / or biodegradable and / or marine-degradable plastic and / or mixtures and / or copolymers of these materials, or is made from at least one of these materials.

[0072] Furthermore, it may be advantageous if the at least one absorber layer comprises 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, or is made of at least one of these materials.

[0073] According to a further development, it is possible that the at least one reflective layer consists of at least one metallic material, in particular selected from the group consisting of silver, copper, aluminum, gold, platinum, niobium, tin, or nickel, titanium, vanadium, chromium, cobalt and palladium or alloys of these materials, in particular cobalt-nickel alloys, or at least one high-refractive-index dielectric material with a refractive index greater than 1.65, in particular selected from the group consisting of zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO2), carbon (C), indium oxide (In2O3), indium tin 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 is made from at least one of these materials.

[0074] Furthermore, a spacer layer can consist of at least a low-refractive-index dielectric material with a refractive index of less than or equal to 1.65, in particular selected from the group consisting of aluminum oxide (Al2O3), metal fluorides, for example magnesium fluoride (MgF2), aluminum fluoride (AIF3), cerium fluoride (CeFs), sodium aluminum fluorides (e.g. Na3AlF6, or Na5Al3F). 14 ), silicon dioxide (SiO₂) 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 a high-refractive-index dielectric material with a refractive index greater than 1.65, in particular selected from the group consisting of zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO2), carbon (C), indium oxide (In2O3), indium tin 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 be made from at least one of these materials.

[0075] Furthermore, it may be provided that the coating is or comprises a metal layer and / or a metal effect layer, in particular a metal effect paint and / or a metal effect varnish and / or a metal effect ink and / or a metallic material, in particular selected from the group consisting of silver, copper, aluminium, gold, platinum, niobium, tin, or from nickel, titanium, vanadium, chromium, cobalt and palladium or alloys of these materials, in particular cobalt-nickel alloys.

[0076] The counterfeit protection can be further increased by using a partial coating that depicts a portrait, landscape, abstract geometric symbol, logo, alphanumeric character, icon, code, or sequence of characters. The relief structures can be embossed directly into the substrate or carrier layer. This can be done, for example, by heating the carrier layer and embossing the structures using an embossing tool, such as an embossing roller. Alternatively, a separate layer, particularly an embossing lacquer layer, can be applied directly to the carrier layer to accommodate the structures. In both cases, the structures can be applied using an embossing device or molding element.

[0077] Furthermore, it is conceivable that sub-areas of at least some of the segments of the relief structure have the same average layer thickness of the coating.

[0078] According to further training, each segment can form a pixel, with each segment preferably comprising at least one structure-forming element or several structure-forming elements. This further increases counterfeit protection.

[0079] A pixel is the smallest unit perceptible to the naked eye. A group of elements is represented within a pixel, visible to the naked eye.

[0080] Additionally, the structure-forming elements may also include reflective and / or refractive and / or diffractive and / or micromirrors and / or at least hologram-forming and / or microlens-forming structures.

[0081] It is also conceivable that the structure-forming elements are achromatic elements.

[0082] Furthermore, the relief structure may be asymmetrical with respect to rotation around an axis normal to a plane of the substrate and translation parallel to the plane of the substrate. This further increases the counterfeit protection.

[0083] Furthermore, a sequence of segments along a direction parallel to the substrate may exhibit a constant or varying spatial frequency. This further increases counterfeit protection.

[0084] Furthermore, it is possible that at least one segment, or each segment of at least some of the segments, forms a freeform optical system in itself. Another embodiment may provide that at least some of the segments are rotationally symmetric and / or translationally symmetric to each other.

[0085] In a further embodiment, the segments can have identical or different outline shapes. This further increases counterfeit protection. Within the segments, the elements can exhibit irregularities in shape, size, etc. The segments themselves can be arranged regularly or irregularly, depending on what is advantageous for the visual effect.

[0086] It is also conceivable that adjacent segments are separated from each other by a segment boundary free of structure-forming elements or by a segment boundary exhibiting elements of a different structure and size than those lying within the adjacent segments. This further increases counterfeit protection.

[0087] Furthermore, a training program may stipulate that the elements of a segment are at least partially of the same and / or different shape and / or size and / or at least partially of the same and / or different orientation. This further increases counterfeit protection.

[0088] It is also advantageous if the segments are arranged regularly and / or irregularly, at least in a portion of the relief structure. This further increases the counterfeit protection.

[0089] The structures themselves can also be used to create motion effects, 3D effects, and similar effects.

[0090] To better understand the invention, it is explained in more detail with reference to the following figures.

[0091] They each show, in a highly simplified, schematic representation:

[0092] Fig. 1 shows a safety element in top view;

[0093] Fig. 2 is a detail view of Fig. 1;

[0094] Fig. 3 shows a possible layer structure of a safety element;

[0095] Fig. 4 shows another safety element in top view; Fig. 5 shows another possible layer structure of a safety element;

[0096] Fig. 6 shows a safety element in schematic representation;

[0097] Fig. 7 a) to e) shows a safety element from different viewing angles;

[0098] Fig. 8 shows another embodiment of a safety element.

[0099] It should be noted at the outset that in the differently described embodiments, identical parts are provided with the same reference numerals or component designations, and the disclosures contained in the entire description can be applied analogously to identical parts with the same reference numerals or component designations. Furthermore, the positional indications chosen in the description, such as top, bottom, side, etc., refer to the figure directly described and illustrated, and these positional indications must be applied analogously to the new position if the position changes.

[0100] It should be mentioned at the outset that the layer structure, as well as the arrangement of further layers, depends on how the safety element is attached to a safety object, since the side of the safety element to be viewed after attachment is decisive. Thus, the visible side can be viewed from above, as shown in the figures, but it is also possible to view the safety element from below, e.g., through a support.

[0101] It should be noted that the phrase "a layer is applied to something" is to be understood as meaning that the layer can be applied directly, or that one or more intermediate layers may be present between the applied layer and the surface to which the layer is applied. It should also be noted that one or more intermediate layers may be arranged between the layers described in this document. Therefore, it is not essential that the described layers are in contact with each other. Furthermore, it should be noted that the term "layer" in this document is to be understood as meaning that a layer can also be composed of several sublayers.

[0102] Where possible, the figures are described below in a single overview to avoid unnecessary repetition. Figures 1 and 4 show a safety element 1 with a planar support substrate 2 and at least one relief structure 3 in a top view, wherein the relief structure 3 represents at least one motif in reflected light and the relief structure 3 has structure-forming three-dimensional elements 4.

[0103] Fig. 2 is a detailed view of Fig. 1 and shows, by way of example, an element 4 formed in one of the segments 5. It is provided that the relief structure 3 is formed by means of a freeform surface and is divided into segments 5 with defined optical properties, in particular ray-optical properties, specifically selected from the group consisting of specular reflection, diffuse reflection, refraction, focusing, divergence, and wave-optical properties, e.g. diffraction.

[0104] According to the invention, the motif appears in a first color depending on the viewing angle, and in a second color different from the first viewing angle, and in a second color different from the first color, wherein the motif appears in at least a third color, which is different from the first and second colors, in a viewing area outside the first and second viewing angles.

[0105] It is possible that each segment 5 forms a pixel, wherein each segment 5, for example, as shown schematically in Fig. 2, preferably comprises at least one structure-forming element 4 or, as indicated by dashed lines, may comprise several structure-forming elements 4.

[0106] It may preferably be provided that the structure-forming elements are 4 achromatic elements.

[0107] It is conceivable that the relief structure 3 is asymmetrical with respect to a rotation about an axis normal to a plane of the support substrate 2 and a translation parallel to the plane of the support substrate 2.

[0108] The segments 5 may have identical outline shapes. This is illustrated by a checkerboard-like grid in Fig. 1. Of course, any other outline shape is also conceivable. Fig. 4 shows that the safety element 1 may also have segments 5 with different outline shapes. For example, one segment 5 may have a rectangular outline shape and another segment 5 a triangular outline shape. This again represents a multitude of conceivable outline shapes. While Fig. 1 shows that the segments 5 can be directly adjacent to each other and separated by segment boundaries 15, Fig. 4 shows that the segments 5 can also be spaced apart. Naturally, combinations of these variations are also conceivable.

[0109] A sequence of segments 5 can exhibit a constant or varying spatial frequency along a direction parallel to the support substrate 2. In Fig. 1, for example, the segments 5 exhibit a constant spatial frequency when viewed from left to right, while the segments 5 in Fig. 4 exhibit a varying spatial frequency. The distance between the lines or segment boundaries 13 corresponds to the spatial frequency.

[0110] As already described, it is also possible that adjacent segments 5 are separated from each other by a segment boundary 15 free of structure-forming elements 4 or by a segment boundary 15 having elements 4 of a different structure and size than those elements 4 lying within the adjacent segments 5.

[0111] The elements 4 of a segment 5 may be at least partially of the same and / or different shape and / or size and / or at least partially of the same and / or different orientation. Figure 1 shows similar segments 5, while Figure 4 illustrates segments 5 of different shapes and sizes.

[0112] It is also conceivable that segments 5 are arranged regularly and / or irregularly, at least in a sub-area of ​​the relief structure 3.

[0113] It is also possible that the relief structure 3 is at least partially provided with at least one reflective and / or optical effect coating 14, in particular an optically variable effect. This is shown, for example, in the cross-sectional view of a safety element 1 according to Fig. 3. The structural parameters of at least individual areas of selected segments, which are also specifically modified, are further indicated schematically in Fig. 3 for easier understanding.

[0114] Figures 3 and 5 show a safety element 1 with a planar support substrate 2 and at least one relief structure 3, wherein the relief structure 3 represents at least one motif in reflected light and the relief structure 3 has structure-forming three-dimensional elements 4. The relief structure 3 forms a free-form optical element and is divided into segments 5 with defined optical properties, in particular ray-optical properties, specifically selected from the group consisting of specular reflection, diffuse reflection, refraction, focusing, divergence, and diffraction.

[0115] Figure 3 shows an embodiment of a safety element 1 in which the relief structure 3 has a substantially planar surface. Figure 5 shows an embodiment of a safety element 1 in which the relief structure 3 has a substantially non-planar surface. Although not explicitly shown, it may well be conceivable and advantageous in the embodiment according to Figure 5 if the relief structure 3 is at least partially provided with at least one reflective and / or optically effective coating 14, in particular an optically variable effect.

[0116] Preferably, it may further be provided that a viewing angle-dependent impression of the motif is created by at least one reflective and / or optical effect coating 14, in particular one that produces an optically variable effect. It may also be provided that the relief structure 3 is at least partially covered with the coating 14.

[0117] The coating 14 can be designed as a color-shifting layer or comprise a color-shifting layer.

[0118] The coating 14 that produces the optical effect may be formed by an optical thin-film element in the form of an interference element. In Fig. 3, this coating 14 is partially implemented. However, a full-surface coating 14 of the relief structures 3 is also conceivable. It may be particularly preferred that the optical effect layer or the coating 14 is designed as a thin-film element and has at least one absorber layer 16 and at least one spacer layer 17.

[0119] Furthermore, the optical effect layer or coating 14, which is designed as a thin-film element, can further comprise at least one reflection layer 18, wherein the at least one spacer layer 17 is arranged between the at least one absorber layer 16 and the at least one reflection layer 18.

[0120] It is also conceivable that the reflective layer is applied to the relief structures 3, in particular printed and / or vapor-deposited.

[0121] One possible embodiment can be designed in such a way that the optical effect layer or coating contains 14 color-tilting pigments, in particular interference pigments, or liquid crystal pigments.

[0122] Furthermore, it can be advantageous that a color shift effect occurs in the coating 14 that produces an optical effect when the light source is moved and / or the viewing angle is changed.

[0123] The coating 14 that produces an optical effect can contain metallic pigments and / or magnetic pigments and / or color pigments and / or dyes.

[0124] It is possible that the coating 14, which produces an optical effect, has at least one layer on a side facing away from a visible side that reinforces the color shift effect.

[0125] Furthermore, it can be advantageous if the coating 14, which produces an optical effect, is printed and / or vapor-deposited onto the relief structures 3.

[0126] It is also possible that the coating 6, which produces an optical effect, has at least one liquid crystal layer, in particular a cholesteric liquid crystal layer.

[0127] It is also conceivable that, in addition to the coating 14 that produces an optical effect, the safety element 1 may contain an optically non-linear layer or an optically non-linear layer and / or a layer containing photoluminescent pigments and / or fluorescent substances. Furthermore, a strongly absorbing dielectric material, such as germanium, can be used as an additional layer. This additional layer can, for example, be applied to the color-shifting optical effect layer or to the coating 14, which may be designed in the form of a thin-film element.

[0128] An alternative embodiment is characterized in that several are arranged in such a way as to form several individual symbols by means of the arrangement of the relief structures 3, which symbols are contained in the view of the image.

[0129] Furthermore, the security element 1 may be equipped with additional color-changing layers, in particular layers with color-changing pigments or liquid crystals and / or with machine-readable features, wherein the machine-readable features are in particular magnetic codings, electrically conductive layers, electromagnetic wave absorbing and / or re-emitting substances.

[0130] It is also conceivable that the security element 1 has further or additional layers, which additional layers include, in particular, protective layers 19 such as protective lacquers, heat-seal lacquers, adhesives, primers and / or films. In Figures 3, 5 and 6, an optional protective layer 19 is indicated by dashed lines.

[0131] The safety element 1 may comprise a support substrate 2 or a support layer made of a plastic, wherein the plastic is in particular made of a translucent and / or thermoplastic plastic, and wherein the support layer preferably comprises at least one of the materials from the group consisting of polyimide PI, polypropylene PP, monoaxially oriented polypropylene MOPP, biaxially oriented polypropylene BOPP, polyethylene PE, polyphenylene sulfide PPS, polyetheretherketone PEEK, polyetherimide PEI, polysulfone PSU, polyaryletherketone PAEK, polyethylene naphthalate PEN, liquid crystalline polymers LCP, polyester, polybutylene terephthalate PBT, polyethylene terephthalate PET, polyamide PA, polycarbonate PC, cycloolefin copolymers COC, polyoxymethylene POM, acrylonitrile butadiene styrene ABS, polyvinyl chloride PVC, ethylene tetrafluoroethylene ETFE, polytetrafluoroethylene PTFE, polyvinyl fluoride PVF, and polyvinylidene fluoride PVDF.Ethylene tetrafluoroethylene hexafluoropropylene fluoropolymer EFEP, cellulose- or lignin-based plastics, polyhydroxyalkanoates PHA, thermoplastic starch TPS, polylactic acid PLA, polycaprolactone PCL, polybutylene succinate PBS, and polybutylene adipate rephthalate PBAT and / or at least one recycled and / or biodegradable and / or marine-degradable plastic and / or mixtures and / or copolymers of these materials, or is made from at least one of these materials.

[0132] Furthermore, it may be advantageous that the at least one absorber layer 16 comprises at least one metallic material, in particular selected from the group consisting of nickel, titanium, vanadium, chromium, cobalt, palladium, iron, tungsten, molybdenum, niobium, aluminium, silver, copper and / or alloys of these materials, or is made of at least one of these materials.

[0133] According to a further development, it is possible that the at least one reflective layer consists of at least one metallic material, in particular selected from the group consisting of silver, copper, aluminum, gold, platinum, niobium, tin, or nickel, titanium, vanadium, chromium, cobalt and palladium or alloys of these materials, in particular cobalt-nickel alloys, or at least one high-refractive-index dielectric material with a refractive index greater than 1.65, in particular selected from the group consisting of zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO2), carbon (C), indium oxide (In2O3), indium tin 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), and 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 is made from at least one of these materials.

[0134] Furthermore, a spacer layer 17 can be at least a low-refractive-index dielectric material with a refractive index less than or equal to 1.65, in particular selected from the group consisting of aluminum oxide Al2O3, metal fluorides, for example magnesium fluoride MgF2, aluminum fluoride AIF3, cerium fluoride CcFs, sodium aluminum fluorides e.g. Na3AlF6, or Na5Al3F 14 , silicon dioxide SiO x, Silicon dioxide SiO2, neodymium fluoride NdFs, lanthanum fluoride LaFs, 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 a high-refractive-index dielectric material with a refractive index greater than 1.65, in particular selected from the group zinc sulfide ZnS, zinc oxide ZnO, titanium dioxide TiO2, carbon C, indium oxide In2O3, indium tin 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 Sm2Ü3, antimony trioxide Sb2O3, silicon carbide SiC, silicon nitride Si3N4, silicon monoxide SiO, selenium trioxide Se2Ü3, tin oxide SnO2, tungsten trioxide WO3, high refractive index organic monomers and / or high refractive index organic polymers or be made from at least one of these materials.

[0135] Furthermore, the coating 14 may be provided to be or comprise a metal layer and / or a metal effect layer, in particular a metal effect paint and / or a metal effect varnish and / or a metal effect ink and / or a metallic material, in particular selected from the group consisting of silver, copper, aluminium, gold, platinum, niobium, tin, or from nickel, titanium, vanadium, chromium, cobalt and palladium or alloys of these materials, in particular cobalt-nickel alloys.

[0136] It is possible that coating 14 is a partial coating and that the coating represents a portrait, a landscape, an abstract geometric symbol, a logo or an alphanumeric character and / or an icon and / or a code and / or a sequence of characters.

[0137] Fig. 6 shows a schematic representation of a safety element 1 according to the invention, in which, between the structure-forming three-dimensional elements 4 of the relief structure 3, which are divided into several segments 5 of defined optical properties, the structure-forming elements 4 in at least one area 10 of one of the segments 5 are designed with respect to their structural properties in such a way as to vary compared to the other elements 4, such that, by means of the interaction of the segments 5 and the coating 14, the motif appears in at least a third color in a viewing area 11 between the first viewing angle 6 and the second viewing angle 8 in the affected area 10.

[0138] The area 10 with the specifically modified or varied elements 4 can be entirely formed by a segment 5.

[0139] Those areas 10 of the relief structure 3 are modified or adapted with respect to their structural properties in such a way that they (in the viewing area) influence the coating 14 with respect to their optical properties, so that the additional impression with respect to at least the third color is obtained.

[0140] As mentioned at the beginning, at least the parameters grid constant 21, depth 22, slope angle 23 and orientation 24 (alignment with respect to an axis perpendicular to the surface plane) of the structures can be changed to influence the properties.

[0141] For the sake of clarity, these structural properties are schematically indicated in Fig. 6.

[0142] To influence the further segments by means of the varyingly formed structure-forming elements, these can influence the further structure-forming elements 4 of the segments 5 with regard to the optical properties, in particular selected from the group directed reflection, diffuse reflection, refraction, focusing, divergence, diffraction, under the viewing angles) in the viewing area 11, so that an additional impression with at least the third color can be obtained.

[0143] Furthermore, the varying structure-forming elements 4 of the areas 10 can preferably be designed such that they do not exert any (perceptible to the eye) influence on the coating 14 under the first viewing angle 6 and / or second viewing angle 8.

[0144] Fig. 7 shows a possible embodiment of a safety element 1, in which different impressions of the safety element are shown, depending on the current viewing angle of the viewer.

[0145] Furthermore, it should be mentioned with regard to the depicted viewing angles that these are schematically indicated outside the safety element for the sake of clarity, but preferably, with regard to a view of the safety element along its longitudinal extent, lie essentially in a plane perpendicular to the safety element and are oriented in this plane (with respect to the surface plane) according to the respective viewing angle values ​​to the safety element.

[0146] According to the representation of the motif of the safety element, this can, for example, exhibit a movement effect according to the sequence in Fig. 7 a) to e) (depending on the viewing angle), which is schematically visible in alternating states of appearance, whereby it should be mentioned that this serves only for illustration and the invention is not limited to this.

[0147] Preferably, in the present invention, the motif effect in the form of a movement effect, 3D effect, or the like, is continuously recognizable in all states, including in the viewing area besides the first and second viewing angles.

[0148] The motif of the security element 1 is also recognizable in the first color 7 from the first viewing angle 6, or appears in this color as indicated in Fig. 7 a). Furthermore, the first color 7 can be seen in lighter areas of the first color 7a and darker areas of the first color 7b. In the example shown, the first viewing angle is 90° with respect to the surface plane 13 of the security element 1, or is perpendicular to it.

[0149] When the current viewing angle is changed to an area outside the first viewing angle 6, namely to the viewing area 11, the third color 12 appears. As is also indicated in Fig. 7 ac), it can be provided that at least one of the colors, comprising the first color 7 and second color 9, is visible in the viewing area 11.

[0150] In this respect, a perceptible color transition can occur (along the viewing area), so that in a viewing angle area which is close to or closer to the first viewing angle 6 according to Fig. 7 b) (for example in a fourth viewing angle), the first color 7 still appears in larger proportions, and the further the viewing angle moves away from the first viewing angle 6, the proportion of the first color 7 decreases.

[0151] Regarding the color transition, one embodiment may provide that, with respect to the viewing angle, in approximately the middle of the viewing area 11, only the third color 12 is visible in a central section (not shown). Furthermore, at least one other color may also be visible in this central section.

[0152] As illustrated in the example shown in Fig. 7 c), it is preferably provided that at a given viewing time, in a central section of the viewing area 11 (with respect to the first and second viewing angles), the first color 7, the second color 9, and the third color 12 all appear. Alternatively, it is also possible that only the third color appears in this section (not shown in Fig. 7).

[0153] In this regard, a possible third viewing angle 20 is indicated, which, for example, with a first viewing angle 6 of 85-95° and a second viewing angle 8 of <=30°, can be within 30° and 85°, preferably in a range of approximately 55-65°.

[0154] As the viewing angle in the viewing area 11 approaches the direction of the second viewing angle 8, it can be provided that the third color 12 and the second color 9 appear, according to Fig. 7 d) (for example in a fifth viewing angle).

[0155] Analogous to the change in color proportions with respect to the approach to or distance from the first viewing angle 6, it can also be provided with respect to the second viewing angle 8 that the proportion of the second color 9 increases as the current viewing angle in the viewing area approaches the second viewing angle 8 (or vice versa decreases).

[0156] Upon reaching the second viewing angle 8, only the second color 9 appears, as shown in Fig. 7 e). Furthermore, it can also be provided that the second color 9 is subdivided into lighter areas of the second color 9a and darker areas of the second color 9b.

[0157] As can further be seen from the figures, with regard to the color impression - in the presence of several colors - it can be provided that the structures of those areas which the elements varying with respect to their structural properties are arranged along the extension direction of the safety element or a direction along the surface plane are arranged in such a repeating manner that the third color 12 and at least one of the colors comprising the first color 7 and the second color 9 appear alternately repeating along the direction.

[0158] Such a repetition can be provided in a longitudinal direction and / or in a lateral direction with respect to the surface plane 13 of the safety element 1. Furthermore, this repeating arrangement can be regular or irregular (e.g., with respect to the sequence of the different colors). As can also be seen from the illustration in Fig. 7 a) to e), the overall impression for the eye can be a shift in the visible colors due to the viewing angle-dependent increase or decrease of the individual proportions of the respective colors, so that an observer gets the impression that individual colored areas are enlarging or shrinking.

[0159] Finally, Fig. 8 schematically shows another possible embodiment of a safety element 1, in which the structure-forming elements 4 of the areas 10 of the segments 5 are arranged with varying structural properties such that, by means of the interaction of the optical properties of these segments 5 of the areas 10 with the coating 14, the viewing area 11 is arranged downstream of the second viewing angle 8, so that the second viewing angle 8 lies between the first viewing angle 6 and the viewing area 11, whereby, when the viewing angle is pivoted along a viewing plane, the motif first appears in the first color, then in the second color, and then, by means of the influence of the segments with the areas 10 on the coating, in the third color.

[0160] In the embodiment according to Fig. 8, it can further be provided that, when transitioning from the second viewing angle 8 towards the viewing area 11, the second color is discernible in addition to the third color. Furthermore, this color can gradually decrease as the current viewing angle moves further away from the second viewing angle 8 – within the viewing area 11.

[0161] Furthermore, the second viewing angle 8 can also be chosen to be significantly smaller with regard to its angular range than is shown in Fig. 8.

[0162] Furthermore, regardless of the embodiment shown, it should be noted that the viewing angles 6 and 8, as well as the additional viewing area 11, can in principle lie in different angular ranges than those shown in the figures, or in different proportions to each other. For example, the first viewing angle can be designed over a larger range, e.g., 70°–110°, and the viewing area can be smaller. Alternatively, the first and second viewing angles, as well as the viewing area, can be designed with approximately the same angular magnitude, e.g., approximately 30° each. However, it is preferable that the first viewing angle be chosen such that its color is visible when viewing the safety element at an angle of 90°. 0 the surface is clearly recognizable.

[0163] The relief structures 3 can be embossed directly into the substrate 2 or into the carrier layer, as shown in Figures 3, 5, and 6. This can be done, for example, by heating the substrate 2 and embossing the relief structures 3 using an embossing tool, such as an embossing roller. Another alternative, not shown in the figures, would be to provide a separate additional layer, in particular an embossing lacquer layer, to receive the relief structures 3. This additional layer can be applied directly to the substrate 2. In both variants, the relief structures 3 can be introduced using an embossing process with a molding device or a molding element.

[0164] Regarding the layer thickness of the coating 14, it should be noted that the layer thickness may vary locally depending on the structures, as the manufacturing process and the geometry of the structures with respect to their contours, especially the extreme areas (e.g. peaks, radii, and other changes in the direction of the contour in the surface) can result in slight differences in thickness.

[0165] It is also possible that at least one segment 5 or each segment 5 of at least a part of the segments 5 forms a freeform optic in itself.

[0166] Furthermore, it is conceivable that at least some of the segments 5 are rotationally symmetric and / or translationally symmetric to each other.

[0167] Finally, for the sake of clarity, it should be noted that, for a better understanding of the structure, some elements have been shown not to scale and / or enlarged and / or reduced in size.

[0168] Furthermore, it should be noted that if only the "coating" is mentioned in the context of the application, this refers to a coating that produces an optically variable effect. Reference numeral list

[0169] Safety element

[0170] a carrier substrate

[0171] Relief structure

[0172] elements

[0173] segments

[0174] first point of view

[0175] first color

[0176] second perspective

[0177] second color

[0178] Area

[0179] Area of ​​consideration

[0180] third color

[0181] Surface level

[0182] coating

[0183] Segment boundary

[0184] absorber layer

[0185] Distance layer

[0186] Reflective layer

[0187] protective layer

[0188] third perspective

[0189] Lattice constant

[0190] depth

[0191] incline angle

[0192] orientation

Claims

Patent claims 1. Safety element (1); comprising a carrier substrate (2) and a relief structure (3) arranged thereon, which in reflected light represents at least one viewing-angle-dependent or viewing-angle-independent motif, wherein the relief structure (3) has structure-forming three-dimensional elements (4) formed by means of a free-form surface which has at least partial irregularities with respect to its optical properties, wherein the relief structure (3) is provided with a coating (14) producing an optically variable effect; and the relief structure (3) is divided into several segments (5) of defined optical properties, by means of which the motif appears in a first color (7) at a first viewing angle (6) and in a second color (9) at a second viewing angle (8), characterized in that in at least one area (10) of the segments (5) the structure-forming elements (4) are designed with respect to their structural properties in such a way as to vary in relation to the other structure-forming elements (4) such that by influencing the coating (14) which produces an optically variable effect by means of the varying structural properties of the structure-forming elements in the area (10) the motif appears in at least a third color (12) in a viewing area (11) outside the first viewing angle (6) and the second viewing angle (8).

2. Safety element (1) according to claim 1, characterized in that the viewing area (11) lies between the first viewing angle (6) and the second viewing angle (8).

3. Safety element (1) according to claim 1, characterized in that the second viewing angle (8) lies between the first viewing angle (6) and the viewing area (11).

4. Safety element (1) according to claims 1 to 3, characterized in that the first viewing angle (6) lies in an angle range of 85° to 95° with respect to a surface plane (13) of the safety element (1).

5. Security element (1) according to any one of claims 1 to 4, characterized in that the second viewing angle (8) or the viewing area (11) lies within an angular range of 30° to 1° with respect to a surface plane (13) of the security element (1).

6. Security element (1) according to any one of claims 1 to 5, characterized in that the third color (12) and at least the first color (7) appear between a central section of the viewing area (11) and the first viewing angle (6).

7. Safety element (1) according to one of claims 1 to 6, characterized in that the third color (12) and at least the second color (9) appear between a middle section of the viewing area (11) and the second viewing angle (8).

8. Security element (1) according to claim 6 or 7, characterized in that along a direction in a surface plane (13) of the security element the segments (5) with the elements (4) which vary in their structural properties are arranged in such a repeating manner that the third color (12) and at least one of the colors comprising the first color (7) and the second color (12) appear alternately repeating along the direction.

9. Safety element (1) according to one of claims 1 to 8, characterized in that, based on the respective influence of the coating (14) by means of the optical properties of the segments (5), the motif appears only in the third color in at least one section of the viewing area (11).

10. Safety element (1) according to one of claims 1 to 9, characterized in that the coating (14) is designed as a color-changing layer or comprises a color-changing layer.

11. Safety element (1) according to one of claims 1 to 10, characterized in that the coating (14) is formed by an optical thin-film element in the form of an interference element.

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