Security element with relief structure

Abstract

The invention relates to a safety element (1) with at least one viewing-angle-dependent impression, comprising a planar support substrate (2) and at least one relief structure (3), wherein the relief structure (3) represents at least one viewing-angle-dependent or viewing-angle-independent motif in reflected light and the relief structure (3) has structure-forming three-dimensional elements (4), characterized in that the relief structure (3) forms a free-form optic and is divided into segments (5) of defined optical properties, in particular ray-optical properties, in particular selected from the group consisting of specular reflection, diffuse reflection, refraction, focusing, divergence, and diffraction, wherein the at least one viewing-angle-dependent impression causes the motif to appear in a first color at at least one first viewing angle and in a second color at a second viewing angle, different from the first viewing angle.different from the first color, making the color appear.

Description

[0001] The invention relates to a security element, in particular for securities, security paper or security objects, such as banknotes, identity cards, credit cards, with at least one viewing angle-dependent impression, comprising a flat 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.

[0002] Security elements of the above-mentioned type are used to protect against counterfeiting of securities, such as banknotes, tickets, etc., security papers and security documents, such as identity cards.

[0003] The object of the present invention is to create a security element with increased protection against counterfeiting.

[0004] At this point, it should be noted that, in the context of the invention, the term "security element" can refer to various types of security elements familiar to those skilled in the art. For example, security elements can be designed as security threads, security strips, security patches, and the like. Of course, other types of security elements known to those skilled in the art are also conceivable.

[0005] This object is achieved by a security element of the type mentioned at the outset in that the relief structure forms a free-form optic and is divided into segments of defined optical properties, in particular ray-optical properties, in particular selected from the group of directed reflection, diffuse reflection, refraction, focusing, divergence, diffraction, wherein the at least one viewing angle-dependent impression makes the motif appear in a first color at least at a first viewing angle and in a second viewing angle different from the first viewing angle in a second color different from the first color.

[0006] The inventive solution increases counterfeit security by creating a free-form relief structure with a color-shift effect. The inventive solution creates a visual appearance that is unique, characteristic, and easily recognizable to the viewer, yet extremely difficult for a counterfeiter to imitate. Because the relief structure is free-form and divided into segments with defined optical properties, it is highly complex, making it considerably more difficult to replicate. Free-form optical surfaces allow light striking the relief structures to be directed in virtually any direction, and they can be optimally tailored to the specific motif being depicted. Combining them with a color-shift effect makes the appearance distinctive and therefore difficult to imitate.

[0007] To produce relief structures, master structures are often transferred into a polymer using an embossing process. As is well known, this often involves repeated replication of the master. Until now, errors in freeform optics could not be completely avoided during these replication steps. However, especially with freeform optics, a nearly perfect copy is required to achieve the desired effects. The inventive subdivision of the relief structures into segments with defined optical properties has made error-free, or at least nearly error-free, replication of master structures with freeform optics possible. The segments contain the desired information of the corresponding freeform optic. This segmentation reduces the complexity of the structures without losing the optical properties.This facilitates the molding of the structures into polymer layers, for example into UV varnishes or thermally deformable polymers, for example into the carrier substrate.

[0008] Furthermore, segmentation leads to optical conditions that are defined in certain areas, which in turn results in a higher light output and thus enables higher-contrast images.

[0009] By using freeform optics, 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, diffraction can be realized in a very small space.

[0010] The motif may represent a portrait, a landscape, an abstract geometric sign, a logo or an alphanumeric character and / or an icon and / or a code and / or a sequence of characters.

[0011] In the context of the invention, the term "segment" refers to the sum of the elements contained therein and can comprise a single element or multiple elements. A structure-forming element is the smallest optically effective unit, e.g., a single micromirror.

[0012] It may be advantageous for the viewing-angle-dependent impression of the motif to be created by at least one reflective coating and / or one that produces an optical effect, in particular an optically variable effect. This further increases the security against counterfeiting.

[0013] The relief structure may also be at least partially coated, further increasing counterfeit security.

[0014] According to a further development, the coating may be designed as a color-shifting layer or include a color-shifting layer. This further increases counterfeit security.

[0015] Furthermore, it is conceivable that the coating is formed by an optical thin-film element in the form of an interference element. This further increases the security against counterfeiting.

[0016] In a further embodiment, it can 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.

[0017] It is also conceivable that the coating has at least one layer on a side facing away from a visible side that enhances the color shift effect.

[0018] It is also possible that sub-areas of at least some of the segments of the relief structure differ from one another at least by the average coating thickness. The average coating thickness is defined as the averaged coating thickness across a segment. This further increases counterfeit security.

[0019] Effect coatings such as color-shifting thin-film elements show their optical effect depending on the layer thickness used. In freeform optics, the

[0020] Layer thicknesses constantly vary due to the vapor deposition processes used, which results in adverse optical effects and / or color errors. Segmentation allows the structures within the segments to be designed in such a way that changes in layer thickness do not lead to such adverse effects.

[0021] Furthermore, the embossed structures can have sections that are inclined differently to a surface of the carrier film, wherein at least one image-forming coating with regions of different opacity is applied to the structures and a layer thickness of the at least one coating depends on an inclination of the sections of the embossed structures.

[0022] A variant has proven particularly advantageous with regard to the production of the security element in which the layer thickness of the coating increases with a decrease in the amount of the inclination of the sections and vice versa.

[0023] According to a preferred embodiment of the invention, it can be provided that a color and / or brightness impression at a location of the coating in daylight depends on the layer thickness of the coating at this location.

[0024] A preferred 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.

[0025] A conceivable 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.

[0026] Furthermore, the optical effect layer or coating formed as a thin-film element can further comprise 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.

[0027] A conceivable structure of a thin-film element can have the following layer sequence: relief structure – reflective layer – spacer layer – absorber layer or relief structure – absorber layer – spacer layer – reflective layer. A further embodiment provides for the reflective layer to be applied to the relief structures, in particular printed and / or vapor-deposited.

[0028] In addition, it may be advantageous if the coating producing an optical effect is printed and / or vapor-deposited onto the relief structures.

[0029] A further embodiment is characterized in that the coating producing an optical effect has at least one liquid crystal layer, in particular a cholesteric liquid crystal layer.

[0030] A further preferred embodiment provides that the security element, in addition to the coating producing an optical effect, contains an optically non-linear layer or an optically non-linear ply and / or a layer containing fluorescent pigments and / or fluorescent substances. Optically non-linear layers or plies, or materials forming this layer, are also referred to as IR upconverters or UV downconverters. These can be materials that 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 upon irradiation with infrared (IR) (λ > 780 nm) and / or ultraviolet (UV) light (λ < 380 nm).Furthermore, it is possible that the optical effect layer contains photoluminescent pigments and / or photoluminescent substances which exhibit an emission in the IR range when excited by electromagnetic radiation.

[0031] Furthermore, a highly absorbent 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 particular, in the form of a thin-film element.

[0032] An alternative embodiment is characterized in that several elements and / or segments are arranged relative to one another in such a way that the arrangement of the structures forms several individual symbols, which symbols are included in the view of the image. This provides a further advantage, since this configuration incorporates an additional security feature.

[0033] It may also be advantageous for the security element to be provided with further color-shifting layers, in particular layers with color-shifting pigments or liquid crystals and / or with machine-readable features, wherein the machine-readable features are in particular magnetic codes, electrically conductive layers, substances that absorb and / or re-emit electromagnetic waves.

[0034] A further possible and possibly alternative embodiment has the features that the security element has further or additional layers, which additional layers comprise in particular protective varnishes, heat-sealing varnishes, adhesives, primers and / or films.

[0035] A preferred embodiment provides that the security element comprises a carrier substrate or a carrier layer made of a plastic, wherein in particular the plastic is formed from a translucent and / or thermoplastic plastic, and that the carrier layer preferably comprises at least one of the materials from the group 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), ethylenetetrafluoroethylene (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 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.

[0036] It may further be advantageous for the at least one absorber layer to comprise at least one metallic material, in particular selected from the group of nickel, titanium, vanadium, chromium, cobalt, palladium, iron, tungsten, molybdenum, niobium, aluminum, silver, copper and / or alloys of these materials, or to be made from at least one of these materials.

[0037] According to a further development, it is possible for the at least one reflection layer to comprise 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-index dielectric material with a refractive index of greater than 1.65, in particular selected from the group consisting of 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 ), iron oxides such as 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 ), high-index organic monomers and / or high-index organic polymers or is made from at least one of these materials.

[0038] Furthermore, a spacer layer can comprise at least one low-refractive dielectric material having a refractive index of less than or equal to 1.65, in particular selected from the group consisting 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 fluorides (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), low-refractive organic monomers and / or low-refractive organic polymers or at least one high-refractive dielectric material having a refractive index of greater than 1.65, in particular selected from the group consisting of 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 ), iron oxides such as 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 ), high-index organic monomers and / or high-index organic polymers or comprise at least one of these materials be manufactured.,

[0039] Furthermore, it can be provided that the coating is or comprises a metal layer and / or 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 nickel, titanium, vanadium, chromium, cobalt and palladium or alloys of these materials, in particular cobalt-nickel alloys.

[0040] The security against counterfeiting can be further increased if the coating is a partial coating and the coating depicts a portrait, a landscape, an abstract geometric symbol, a logo or an alphanumeric symbol and / or an icon and / or a code and / or a sequence of symbols.

[0041] The relief structures can be embossed directly into the carrier substrate or carrier layer. For example, by heating the carrier layer and embossing the structures using an embossing tool, such as an embossing roller. Another alternative possibility would be to provide a separate additional layer, particularly an embossing lacquer layer, to accommodate the structures. The additional layer can be applied directly to the carrier layer. In both variants, the structures can be introduced using a molding device or a molding element in an embossing process.

[0042] 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.

[0043] A further development may provide that a local layer thickness of the coating depends on the shape and / or size and / or orientation of the elements.

[0044] According to a further development, each segment may form a pixel, with each segment preferably comprising at least one structure-forming element or several structure-forming elements. This further increases the security against counterfeiting.

[0045] A pixel is the smallest unit visible to the naked eye. A group of elements is visible to the naked eye in a pixel.

[0046] In addition, the structure-forming elements may also comprise reflective and / or refractive and / or diffractive and / or micromirrors and / or structures forming at least one hologram and / or microlenses.

[0047] It is also conceivable that the structure-forming elements are achromatic elements.

[0048] In addition, the relief structure may be asymmetrical with respect to rotation about an axis perpendicular to a plane of the carrier substrate and translation parallel to the plane of the carrier substrate. This further increases counterfeit security.

[0049] In addition, a sequence of segments along a direction parallel to the carrier substrate may exhibit a constant or varying spatial frequency. This further increases counterfeit security.

[0050] In addition, it may be that at least one segment or each segment of at least part of the segments forms a free-form optic.

[0051] A further embodiment may provide that at least some of the segments are rotationally symmetrical and / or translationally symmetrical to one another.

[0052] In a further embodiment, the segments can have identical or different outline shapes. This further increases counterfeit security. Within the segments, the elements can exhibit irregularities in shape, size, etc. The segments themselves can be arranged regularly or irregularly, depending on how this is advantageous for the visual effect.

[0053] It is also conceivable that adjacent segments are separated from each other by a segment boundary free of structural elements or by a segment boundary containing elements of a different structure and size than those within the adjacent segments. This further increases counterfeit security.

[0054] In a further development, it may also be provided 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 the security against counterfeiting.

[0055] It is also advantageous if the segments are arranged regularly and / or irregularly, at least in part of the relief structure. This further increases counterfeit security.

[0056] For a better understanding of the invention, it is explained in more detail using the following figures.

[0057] They show in a highly simplified, schematic representation: Fig. 1a security element in plan view, Fig. 2a detailed view of the Fig. 1 , Fig. 3 a possible layer structure of a security element, Fig. 4 another security element in plan view, Fig. 5 another possible layer structure of a security element.

[0058] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied analogously to the new position in the event of a change in position.

[0059] At this point, it should be noted that the phrase "a layer is applied to something" should be understood to mean that the layer can be applied directly, or that one or more intermediate layers can be located between the applied layer and the material to which it is applied. It should also be noted that one or more intermediate layers can be arranged between the layers described in this document. It is therefore not absolutely necessary for the described layers to contact one another. Furthermore, it should be noted that the term "layer" in this document should be understood to mean that a layer can also be composed of several sublayers.

[0060] As far as possible, the figures are described below in summary to avoid unnecessary repetition.

[0061] In the Fig. 1 and 4a security element 1 with a planar carrier substrate 2 and at least one relief structure 3 is shown in plan 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. The Fig. 2 is a detailed view of the 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 forms a free-form optic and is divided into segments 5 of defined optical properties, in particular ray-optical properties, in particular selected from the group of directed reflection, diffuse reflection, refraction, focusing, divergence, diffraction, wherein the at least one viewing angle-dependent impression makes the motif appear in a first color at least at a first viewing angle and in a second viewing angle different from the first viewing angle in a second color different from the first color.

[0062] It may be that each segment 5 forms a pixel, where each segment 5 is, for example, as shown in the Fig. 2 shown roughly schematically, preferably comprises at least one structure-forming element 4 or, not shown figuratively, comprises several structure-forming elements 4.

[0063] It is possible that the structure-forming elements are 4 achromatic elements.

[0064] It is conceivable that the relief structure 3 is designed asymmetrically with respect to a rotation about an axis running normal to a plane of the carrier substrate 2 and a translation parallel to the plane of the carrier substrate 2.

[0065] It is possible that the segments 5 have the same outline shapes. This is exemplified in the Fig. 1 shown using a checkerboard grid. Of course, any other outline shape is also conceivable. Fig. 4 It is shown that the security element 1 can also have segments 5 with different outline shapes. For example, one segment 5 can have a rectangular outline and another segment 5 can have a triangular outline. This, in turn, is representative of a multitude of conceivable outline shapes. While in the Fig. 1 It is shown that the segments 5 can be directly adjacent to each other and can be separated by segment boundaries 7, is shown in the Fig. 4 It has been shown that segments 5 can also be spaced apart from each other. Of course, combinations of these variants are also conceivable.

[0066] A sequence of segments 5 can have a constant or varying spatial frequency along a direction parallel to the carrier substrate 2. In the Fig. 1 For example, when viewing the image from left to right, the segments 5 have a constant spatial frequency, while the segments 5 in the Fig. 4 have a varying spatial frequency. The distance between the lines or segment boundaries 7 corresponds to the spatial frequency.

[0067] As already described, it may also be the case that adjacent segments 5 are separated from one another by a segment boundary 7 that is free of structure-forming elements 4 or by a segment boundary 7 that has elements 4 of a different structure and size than those elements 4 lying within the adjacent segments 5.

[0068] It may be that the elements 4 of a segment 5 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. Fig. 1 similar segments 5 are shown, while the Fig. 4 exemplary segments 5 of different shapes and sizes.

[0069] It is also conceivable that the segments 5 are arranged regularly and / or irregularly at least in a partial area of ​​the relief structure 3.

[0070] It may also be the case that the relief structure 3 is at least partially provided with at least one coating 6 that produces a reflective effect and / or an optical effect, in particular an optically variable effect. This is shown, for example, in the sectional view of a security element 1 according to Fig. 3 is shown schematically.

[0071] Here the Fig. 3 and the Fig. 5 a security element 1 with a planar carrier 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. It is provided that the relief structure 3 forms a freeform optic and is divided into segments 5 of defined optical properties, in particular ray-optical properties, in particular selected from the group of directed reflection, diffuse reflection, refraction, focusing, divergence, and diffraction.

[0072] In the Fig. 3 an embodiment of a security element 1 is shown in which the relief structure 3 has a substantially planar surface. Fig. 5 An embodiment of a security element 1 is shown in which the relief structure 3 has a substantially non-planar surface. Although not explicitly shown, it can also be the case in the embodiment according to Fig. 5 It may well be conceivable and advantageous if the relief structure 3 is at least partially provided with at least one coating 6 which produces a reflective effect and / or an optical effect, in particular an optically variable effect.

[0073] It may be that the viewing angle-dependent impression of the motif is produced by at least one coating 6 that reflects and / or produces an optical effect, in particular an optically variable effect.

[0074] It is conceivable that the relief structure 3 is at least partially provided with the coating 6.

[0075] The coating 6 can be formed as a color-shifting layer or comprise a color-shifting layer.

[0076] It may be that the coating 6 causing the optical effect is formed by an optical thin-film element in the form of an interference element. Fig. 3 This coating 6 is applied partially. However, a full-surface coating 6 of the relief structures 3 is also conceivable. The optical effect layer or coating 6 may be formed as a thin-film element and include at least one absorber layer 9 and at least one spacer layer 10.

[0077] Furthermore, the optical effect layer or coating 6 formed as a thin-film element can further comprise at least one reflective layer, wherein the at least one spacer layer 10 is arranged between the at least one absorber layer 9 and the at least one reflective layer. This is not shown in the figure.

[0078] It is also conceivable that the reflection layer is applied to the relief structures 3, in particular printed and / or vapor-deposited.

[0079] A possible embodiment can be designed in that the optical effect layer or the coating 6 contains color-shifting pigments, in particular interference pigments, or liquid crystal pigments.

[0080] Furthermore, it may be advantageous that a color shift effect occurs in the coating 6 producing an optical effect when the light source moves and / or the angle of observation changes.

[0081] The coating 6 producing an optical effect may comprise metallic pigments and / or magnetic pigments and / or color pigments and / or dyes.

[0082] It may be that the coating 6 producing an optical effect has at least one layer enhancing the color shift effect on a side facing away from a visible side.

[0083] In addition, it may be advantageous if the coating 6 producing an optical effect is printed and / or vapor-deposited onto the relief structures 3.

[0084] It may also be that the coating 6 producing an optical effect has at least one liquid crystal layer, in particular a cholesteric liquid crystal layer.

[0085] It is also conceivable that the security element 1, in addition to the coating 6 producing an optical effect, contains an optically non-linear layer or an optically non-linear layer and / or a layer containing fluorescent pigments and / or fluorescent substances.

[0086] Furthermore, a highly absorbent dielectric material, such as germanium, can be used as an additional layer. This additional layer can be applied, for example, to the color-shifting optical effect layer or to the coating 6, which can be designed, in particular, in the form of a thin-film element.

[0087] An alternative embodiment is characterized in that several are arranged relative to one another in such a way that by means of the arrangement of the relief structures 3 several individual symbols are formed, which symbols are included in the view of the image.

[0088] Furthermore, the security element 1 may be provided with further color-shifting layers, in particular layers with color-shifting pigments or liquid crystals and / or with machine-readable features, wherein the machine-readable features are in particular magnetic codes, electrically conductive layers, substances absorbing and / or re-emitting electromagnetic waves.

[0089] It is also conceivable that the security element 1 has further or additional layers, which additional layers comprise in particular protective layers 8 such as protective lacquers, heat-sealing lacquers, adhesives, primers and / or foils. Fig. 3 and Fig. 5 An optional protective layer 8 is indicated by dashed lines.

[0090] It may be that the security element 1 comprises a carrier substrate 2 or a carrier layer made of a plastic, wherein in particular the plastic is formed from a translucent and / or thermoplastic plastic, and that the carrier layer preferably comprises at least one of the materials from the group polyimide PI, polypropylene PP, monoaxially oriented polypropylene MOPP, biaxially oriented polypropylene BOPP, polyethylene PE, polyphenylene sulfide PPS, polyether ether ketone, PEEK polyether ketone PEK, polyethylene imide PEI, polysulfone PSU, polyarylether ketone 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, 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 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.

[0091] It may also be advantageous for the at least one absorber layer 9 to comprise at least one metallic material, in particular selected from the group of nickel, titanium, vanadium, chromium, cobalt, palladium, iron, tungsten, molybdenum, niobium, aluminum, silver, copper and / or alloys of these materials, or to be made from at least one of these materials.

[0092] According to a further development, it is possible for the at least one reflection layer to comprise 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-index dielectric material with a refractive index of greater than 1.65, in particular selected from the group consisting of 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 , iron oxides such as 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 , high-refractive organic monomers and / or high-refractive organic polymers or is made from at least one of these materials.

[0093] Furthermore, a spacer layer 10 can comprise at least one low-refractive dielectric material having a refractive index of less than or equal to 1.65, in particular selected from the group consisting 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 fluorides, for example 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, low-refractive organic monomers and / or low-refractive organic polymers or at least one high-refractive dielectric material having a refractive index of greater than 1.65, in particular selected from the group consisting of 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 ,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 Pr6O11, 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-index organic monomers and / or high-index organic polymers or be made from at least one of these materials.

[0094] Furthermore, it can be provided that the coating 6 is or comprises a metal layer and / or 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 nickel, titanium, vanadium, chromium, cobalt and palladium or alloys of these materials, in particular cobalt-nickel alloys.

[0095] It may be that the coating 6 is a partial coating and the coating represents a portrait, a landscape, an abstract geometric sign, logo or an alphanumeric character and / or an icon and / or a code and / or a sequence of characters.

[0096] The relief structures 3 can be as in the Fig. 3 and Fig. 5 shown, are embossed directly into the carrier substrate 2 or into the carrier layer. For example, by heating the carrier substrate 2 and embossing the relief structures 3 using an embossing tool, such as an embossing roller. Another alternative possibility, not shown in the figure, would be to provide a separate additional layer, in particular an embossing lacquer layer, to accommodate the relief structures 3. The additional layer can be applied directly to the carrier substrate 2. In both variants, the relief structures 3 can be introduced using a molding device or a molding element in an embossing process.

[0097] It is conceivable here that partial areas of at least some of the segments 5 of the relief structure 3 differ from one another at least by an average layer thickness of the coating 6.

[0098] In addition, it may be that partial areas of at least some of the segments 5 of the relief structure 3 have the same average layer thickness of the coating 6.

[0099] Furthermore, a local layer thickness of the coating 6 may depend on the shape and / or size and / or orientation of the elements 4.

[0100] It may also be the case that at least one segment 5 or each segment 5 of at least a part of the segments 5 forms a free-form optic.

[0101] Furthermore, it is conceivable that at least some of the segments 5 are rotationally symmetrical and / or translationally symmetrical to one another.

[0102] All information on value ranges in this description is to be understood as including any and all sub-ranges thereof, e.g. the information 1 to 10 is to be understood as including all sub-ranges starting from the lower limit of 1 and the upper limit of 10, ie all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0103] For the sake of clarity, it should finally be pointed out that, in order to better understand the structure, some elements have been shown out of scale and / or enlarged and / or reduced in size.

[0104] By way of introduction, it should be mentioned that the layer structure, as well as the arrangement of further layers, depends on the type of application of the security element to a security object, since the side of the security element to be viewed after application is crucial. Thus, the visible side can be viewed from above, as shown in the figures, but it is also possible to view the security element from below, e.g., through a support. Bezugszeichenaufstellung

[0105] 1Security element 2Carrier substrate 3Relief structure 4Element 5Segment 6Coating 7Segment boundary 8Protective layer 9Absorber layer 10Spacer layer

Claims

1. Security element (1) with at least one viewing angle-dependent impression, comprising a flat carrier substrate (2) and at least one relief structure (3), wherein the relief structure (3) represents at least one viewing angle-dependent or viewing angle-independent motif in reflected light and the relief structure (3) has structure-forming three-dimensional elements (4), characterized in that the relief structure (3) forms a free-form optic and is divided into segments (5) of defined optical properties, in particular ray-optical properties, in particular selected from the group of directed reflection, diffuse reflection, refraction, focusing, divergence, diffraction, wherein the at least one viewing angle-dependent impression makes the motif appear in a first color at least at a first viewing angle and in a second viewing angle different from the first viewing angle in a second color different from the first color.

2. Security element (1) according to claim 1, characterized in that the viewing angle-dependent impression of the motif is produced by at least one coating (6) which produces a reflective and / or optical effect, in particular an optically variable effect.

3. Security element (1) according to claim 2, characterized in that the relief structure (3) is at least partially provided with the coating (6).

4. Security element (1) according to claim 2 or 3, characterized in that the coating (6) is designed as a color-shifting layer or comprises a color-shifting layer.

5. Security element (1) according to one of claims 2 to 4, characterized in that the coating (6) is formed by an optical thin-film element in the form of an interference element.

6. Security element (1) according to one of claims 2 to 5, characterized in thatthe coating (6) contains color-shifting pigments, in particular interference pigments, or liquid crystal pigments, or that the coating (6) contains metallic pigments and / or magnetic pigments and / or color pigments and / or dyes.

7. Security element (1) according to one of claims 2 to 6, characterized in that the coating (6) has at least one layer enhancing the color shift effect on a side facing away from a visible side.

8. Security element (1) according to one of claims 2 to 7, characterized in that Partial regions of at least some of the segments (5) of the relief structure (3) differ from one another at least by an average layer thickness of the coating (6).

9. Security element (1) according to one of claims 2 to 8, characterized in that Partial regions of at least some of the segments (5) of the relief structure (3) have the same average layer thickness of the coating (6).

10. Security element (1) according to one of claims 2 to 9, characterized in that a local layer thickness of the coating (6) depends on the shape and / or size and / or orientation of the elements (4).

11. Security element (1) according to one of claims 1 to 10, characterized in that each segment (5) forms a pixel, wherein each segment (5) preferably comprises at least one structure-forming element (4) or several structure-forming elements (4).

12. Security element (1) according to one of claims 1 to 12, characterized in that the relief structure (3) is formed asymmetrically with respect to a rotation about an axis running normal to a plane of the carrier substrate (2) and a translation parallel to the plane of the carrier substrate (2).

13. Security element (1) according to one of claims 1 to 5, characterized in that a sequence of segments (5) along a direction parallel to the carrier substrate (2) has a constant or varying spatial frequency.

14. Security element (1) according to one of claims 1 to 13, characterized in that at least one segment (5) or each segment (5) of at least a part of the segments (5) forms a free-form optic.

15. Security element (1) according to one of claims 1 to 14, characterized in that at least some of the segments (5) are rotationally symmetrical and / or translationally symmetrical to one another.

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