Security element for a value document, value document, and method for producing a security element
Patent Information
- Application Number
- EP2023709591
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-03-07
- Filing Date
- 2023-03-07
- Publication Date
- 2025-01-15
AI Technical Summary
Existing security elements for documents of value lack enhanced security against forgery and are easily noticeable when viewed from above, as they do not provide sufficient angle-dependent visibility of multiple views.
A security element with a substrate body having a see-through element featuring alternately arranged micro-image elements and micro-imaging elements, which provide different views when viewed from specific angles, with the micro-image elements nested to create a dynamic pseudo-watermark effect, increasing security and camouflage in reflection while being visible in transmission.
The solution enhances security against forgery by providing multiple angle-dependent views that are camouflaged in reflection but visible in transmission, improving authenticity checks and reducing the visibility of the security feature in reflective light while maintaining visibility in transmitted light, thus increasing the complexity and effectiveness of the security element.
Smart Images
Figure 1.1
Abstract
Description
[0001] Safety element for clean
[0002] Value document, value document and process for producing one
[0003] Safety elements
[0004] The invention relates to a security element for a value document, wherein the security element comprises a substrate body having a front and a back, and a see-through element which presents a see-through image to a viewer in see-through.
[0005] Such a security element is already known from EP 3268235 B1. A security document is disclosed which comprises a paper strip embedded in its substrate body, which has a see-through element that presents a see-through image to the viewer.
[0006] The object of the invention is to provide a security element for a value document whose see-through element is more concise, increases the security against forgery and is hardly perceptible when viewed from above.
[0007] The invention is defined in claims 1, 14 and 15. The subclaims relate to preferred embodiments.
[0008] A security element for a value document is provided, comprising a substrate body having a front and a back side and a see-through element that presents a see-through image to a viewer. The see-through element comprises micro-imaging elements and first micro-image elements and second micro-image elements arranged alternately in a micro-image layer, wherein the micro-image layer is applied to the front or back side of the substrate body or is embedded therein, and the micro-imaging elements image the micro-image elements.The first microimage elements, together with the microimage elements spatially assigned to them, provide a first view of the transparency image that can be seen from a first viewing angle range, and the second microimage elements, together with the microimage elements spatially assigned to them, provide a second view of the transparency image that can be seen from a second viewing angle range, wherein the microimage elements are arranged such that the views are nested with respect to the microimage layer, and the first view differs in its translucency from the second view.
[0009] The micro-imaging elements ensure that the first and second micro-image elements, and thus the views generated by them, are visible from a respective, specified first and second viewing angle range. Outside of the viewing angle range, they cannot be perceived with the naked eye. In the first viewing angle range, the first view of the transparent image is visible due to the interaction of the micro-imaging elements and the first micro-image elements; in the second viewing angle range, the second view of the transparent image is visible due to the interaction of the micro-imaging elements with the second micro-image elements. Each view of the transparent image is assigned a specific viewing angle range in which the respective view is recognizable. The viewing angle ranges of the multiple views can overlap or be the same, i.e.From certain viewing angles, multiple views can also be perceived simultaneously. However, they are preferably separate, in particular completely separate. The first and second microimage elements are nested, i.e., they are formed, for example, in the form of a plurality of vertically or horizontally extending channels in the microimage layer, with a channel with second microimage elements following a channel with first microimage elements, etc.
[0010] The first microimage elements and the second microimage elements represent different types. The number of microimage element types, and thus the views that can be perceived from different viewing angles, is not limited to two. Three, four, five, etc. types of microimage elements are possible. The transparent image usually has as many views as there are types of microimage elements.
[0011] A distinction is made here between a see-through element and a see-through image. A see-through image is the visible image that the viewer perceives in transmitted light. The see-through element, on the other hand, refers to the structure that creates the respective see-through image. It is composed of the micro-image elements and the micro-image layer, which contains the alternately arranged micro-image elements. Due to the interaction of the micro-image layer with the micro-image elements, the see-through element presents the viewer with a viewing-angle-dependent see-through image, namely the various views. It differs from a conventional see-through image in that its views depend on the viewing angle.
[0012] The substrate body is preferably made of paper or a polymer. If the substrate body is paper, it is made of plant fibers such as cotton, linen, abacca, etc. and / or synthetic fibers. Polymer substrates such as BOPP or PET are also used as substrate bodies. Composite film substrates are also possible.
[0013] Located on the front or back of the substrate body, or embedded within it, is the see-through element, which comprises the micro-imaging elements and the micro-image layer. The micro-image layer contains several types of micro-image elements, each of which, in conjunction with the micro-imaging elements, provides the views for the see-through image. The multiple views differ in their tonality or opacity.
[0014] The see-through element has micro-imaging elements that match the micro-image layer. These elements are arranged above the micro-image layer, i.e., in front of the micro-image layer in a viewing direction. The micro-imaging elements ensure that when the viewing angle changes in transmission, the first and / or second type of micro-image elements, and thus the first and / or second view, are visible. The see-through element thus provides the see-through image depending on the viewing angle.
[0015] When viewed in reflection, views preferably have the same color impression, which in embodiments corresponds to the color impression of the background, for example that of the substrate body. The first and second views take the form of text, an image, a pattern, etc. However, the first view differs from the second view in its opacity or translucency, so that the two views can be distinguished in transmission in addition to the viewing angle dependency. The first and second microimage elements essentially have the same color impression when viewed in reflection. This camouflages the see-through image when viewed in reflected light, whereas when viewing the security element in transmission, the two views are perceived as different motifs for the see-through element, depending on the viewing angle.The micro-image elements arranged in front of the micro-image layer make the micro-image elements of the micro-image layer dynamic, i.e., dependent on the viewing angle. This increases counterfeit security.
[0016] In a preferred embodiment, the security element comprises a first camouflage layer and a second camouflage layer, with the microimage layer located between the first camouflage layer and the second camouflage layer. Preferably, the first camouflage layer and / or the second camouflage layer is an ink-receiving layer.
[0017] By arranging the microimage layer in a layer sequence between the first and second camouflage layers, the effect of double-sided camouflage of the transparent image is improved, thus reducing the visibility of the transparent image when viewing the security element in reflected light, i.e., in incident light. The design of the first or second camouflage layer as an ink-receiving layer, particularly as an opaque white layer, also improves the camouflage effect.
[0018] Particularly preferably, the first camouflage layer and / or the second camouflage layer are applied in a grid. This further improves the camouflage effect; ie, the recognizability of the transparent image when viewed in reflection is reduced. The micro-imaging elements of the transparent image can be designed differently. In a preferred embodiment, the micro-imaging elements are lenticular lenses (= rod lenses). They can be oriented differently in different sub-regions of the security element, ie, extend along different, sub-region-specific directions.
[0019] In a further preferred embodiment, the micro-imaging elements are spherical lenses. They can be arranged in different grid geometries in subregions of the security element. Hexagonal, square, or parallelogram-shaped grids are possible, but a random arrangement is also possible. Lenses with a regular or irregular outline or 3D profile are also possible. In further embodiments, the micro-imaging elements can be Fresnel lenses.
[0020] In a further preferred embodiment, the micro-imaging elements can be prisms that create a flip effect. Like the lenticular lenses, these can also be oriented differently in different subregions of the security element.
[0021] In a further embodiment, the micro-imaging elements can also be a hole pattern or grid, or a locally and / or demetallized layer within a grid. The hole size or the area ratio of metallized to demetallized areas can vary depending on the position in order to convey locally different brightness and sharpness / blurrency impressions. The substrate body is preferably made of polymer. Anti-counterfeiting effects can then be created in various variants using the see-through element. Such a see-through element, encompassed by a security element with a polymer substrate body, is also referred to herein as a dynamic pseudo-watermark.
[0022] In a first variant of the dynamic pseudo watermark, at least two (but not necessarily all) types of microimage elements produce the same color impression when viewed in reflection, thus creating a uniform motif. However, when viewed in transmission, the different tonality of the different views is recognizable. In the first variant, the ink-receiving layer is printed in the same color as the views and in a grid pattern, so that brighter areas, i.e., areas without a grid overprint, are more easily recognized in transmission than areas where the grid is printed (grid print areas).
[0023] In a second variant of the dynamic pseudo watermark, a transparency constructed from multiple views of the transparency is printed and fully underprinted or overprinted with the ink-receiving layer, with an opaque white ink being particularly preferred as the ink-receiving layer. The full-surface application of the ink-receiving layer essentially produces the same effect as applying the ink-receiving layer as a raster in the first variant, namely camouflage of the transparency. By overprinting or underprinting with the ink-receiving layer, the visibility of the transparency is reduced when viewed in reflection (the transparency is camouflaged), whereas the transparency becomes visible when viewed in transmission. In a third variant of the dynamic pseudo watermark, the microimage elements are printed using reflective ink; metallic pigment ink is particularly preferred here.The microimage layer printed with reflective ink (consisting of alternating types of microimage elements) is then over- and undersuppressed on both sides with an ink-receiving layer (specifically, an opaque white ink), so that the multiple views are not visible when viewed in reflection, but are visible with high contrast when viewed in transmission. Essentially the same effect is created as in the second variant, but the views are perceived with greater contrast due to the microimage elements printed with reflective ink.
[0024] As an alternative to printing a reflective ink, a film can also be applied as the microimage layer, which already contains the microimage elements. For example, the transfer element can contain the two microimage elements in the form of metallized and demetallized areas. In this embodiment, the microimage layer is applied to the substrate body by film transfer.
[0025] In a fourth variant of the dynamic pseudo watermark, the microimage elements of the microimage layer can be printed in multiple or true colors, with an opaque white color being applied over and under the image on both sides for camouflage purposes. This means that the colorful motif, composed of the multiple views of the transparent image, cannot be seen when viewed in reflection, but only when viewed in transmission. The substrate body can also be made of paper. For the purposes of this application, this is referred to as a true watermark.
[0026] In genuine watermarks, the see-through element is overprinted with a screen. The external color impression of the screen is identical to the surrounding color of the substrate body, so that the overprint with the screen is barely noticeable when viewed in reflection, but when viewed in transmission, the screen print areas are significantly more opaque than the non-overprinted translucent areas. A genuine watermark is produced as a high-resolution, nested, multi-channel see-through element using high-resolution watermark technology (e.g., 3D-printed screen or screen inserts), with one micro-image element having the dimension of the width of two channel-shaped micro-image elements.The genuine watermark can alternatively be created using high-resolution laser etching, where high-resolution microimage elements are interleaved using multiple channels (creating a dynamic, interleaved, multi-channel see-through element). The microimage elements make the high-resolution microimage elements dependent on the viewing angle, creating a dynamic effect in the multiple views that together form the see-through image. The microimage elements can also be created as in the third variant of the pseudo-watermark—i.e., by printing or applying them as a transfer element—although overprinting is recommended here to camouflage the microimages.
[0027] If the see-through element is a genuine watermark (the substrate is made of paper), different effects can be created. In one variant, the first view can depict a laterally structured motif, while the second view can depict no further structured motif (for example, a second view could be a surface in a uniform color). This creates the effect that the first view (i.e., the motif) appears as a see-through image and disappears when tilted, switching from the first to the second viewing angle.
[0028] In another variant of the genuine watermark, the first view can feature a first motif and the second view a second motif, so that when viewed in transmission, tilting the security element and the associated change from the first to the second viewing angle creates a flip image between the two motifs. The first view can also depict a positive motif and the second view a negative motif, so that when viewed in transmission, a positive-to-negative flip occurs when tilting.
[0029] The see-through element (i.e., the dynamic pseudo watermark and the genuine watermark) is significantly more attractive than a conventional, static see-through element without micro-image elements. The see-through element, the most well-known security element on a banknote, is thus significantly enhanced. Authenticity verification is improved. Furthermore, the dynamic design of the see-through element with micro-image elements significantly increases the barrier to counterfeiting. A conventional see-through element, e.g., as a static background motif, can be used additionally to complement the dynamic see-through element and enhance the transition from the first to the second view of the see-through image when the viewing angle changes.
[0030] It is also preferably possible to arrange the micro-imaging elements and the micro-image layer offset in the see-through element, creating dynamic effects such as a running effect, pumping, or morphing. In addition to tilt effects, moiré-enhancing effects and modulo mapping effects in combination with a tilt effect are also possible. This increases the complexity of the optical effect and thus the security against counterfeiting.
[0031] Preferably, the micro-imaging elements of the see-through element can provide additional views. By supplementing the security element with other features such as blind features, latent images, micro-mirror effects, and magnetically alignable optically variable effect pigments adjacent to the see-through element, various optically variable effects can occur in the security element when tilted in different directions. The dynamic effects of the see-through element and / or additional security elements can occur when tilted about the same and / or different tilt axes. Different tilt axes can advantageously be at right angles to each other. Advantageously, the tilt axes often correspond to the longitudinal or transverse axis of the substrate body.
[0032] The preferred micro-imaging element is an applied film with a pattern of holes or stripes, in which transparent or translucent and opaque areas periodically alternate. Structured metallic coatings are particularly suitable in this context, e.g., a metal layer with round or striped openings or regularly arranged metallic thin-film elements such as platelets or stripes against a transparent background. The same optical effect can also be created by partially printing metallic pigments. The micro-imaging elements can be camouflaged by additional overprinting with opaque white. This prevents the elements from having a metallic sheen and making them easily distinguishable from the substrate, even in reflection. Overprinting with opaque white serves to camouflage these elements.
[0033] By using a partially metallized film that is subsequently camouflaged by overprinting in the area of the see-through element, film-based optically variable security features can be easily implemented in the vicinity, e.g., holograms, micromirrors with and without CS coating, etc.
[0034] If the see-through element consists of a print, foil-based security features can also be applied adjacent to it, but other printed features, such as magnetically alignable effect pigments, are preferred. The other optically variable features can be designed to reveal their optical variability when tilted around the same or a different axis.
[0035] It is possible for the microimage layer and / or the camouflage layers to contain machine-readable substances. For example, the microimage layer and / or the first or second camouflage layer can contain hidden machine-readable feature substances, fluorescent, phosphorescent, magnetic, or IR-absorbing or IR-transparent substances. Transmission sensors with directed oblique light illumination can then additionally detect the see-through image of the see-through element, which is composed of the multiple views, through image mapping under diffuse illumination. In this way, the see-through element can also be detected by machine. Furthermore, a value document is provided to which the security element according to the invention is applied as a patch or strip. The application of the see-through element as a partial region of an optically variable film element is also possible.
[0036] Further provided is a method for producing a security element for a value document, in which a substrate body having a front side and a back side, and a see-through element which presents a see-through image to a viewer when viewed through, are provided. The see-through element is provided with micro-imaging elements and first micro-image elements and second micro-image elements arranged alternately in a micro-image layer, wherein the micro-image layer is applied to the front side or the back side of the substrate body or is embedded therein and the micro-image elements are imaged by the micro-imaging elements. A first view of the see-through image, recognizable from a first viewing angle, is imaged by the first micro-image elements together with the micro-imaging elements.A second view of the transparency image, recognizable from a second viewing angle, is imaged by the second microimage elements together with the microimage elements, and the microimage elements are arranged such that the views are nested with respect to the microimage layer, and the first view differs in its translucency from the second view.
[0037] The described embodiments and variants apply equally to the security element and the method.
[0038] The invention is explained below using exemplary embodiments under
[0039] Reference to the accompanying drawings, which also disclose features essential to the invention, will be explained in more detail. These embodiments are for illustrative purposes only and are not to be interpreted as restrictive. For example, a description of an embodiment with a plurality of elements or components should not be interpreted as meaning that all of these elements or components are necessary for implementation. Rather, other embodiments may also contain alternative elements and components, fewer elements or components, or additional elements or components. Elements or components of different embodiments may be combined with one another unless otherwise stated. Modifications and variations described for one of the embodiments may also be applicable to other embodiments.To avoid repetition, identical or corresponding elements in different figures are designated by the same reference numerals and are not explained more than once. The figures show:
[0040] Fig. 1 to Fig. 3 embodiments of a security element with a substrate body made of polymer in sectional view,
[0041] Fig. 4 to Fig. 8 embodiments of a security element with a substrate body made of paper in sectional view,
[0042] Fig. 9 Micro imaging elements as lenticular lenses in isometric view,
[0043] Fig. 10 Micro imaging elements as prisms in isometric
[0044] Illustration, Fig. 11 Micro imaging elements in the form of lenticular lenses or prisms in plan view,
[0045] Fig. 12 Micro imaging elements as spherical lenses in isometric view,
[0046] Fig. 13 and Fig. 14 arrangements of micro imaging elements as spherical lenses in plan view,
[0047] Fig. 15 and Fig. 16 security elements with partial areas with different orientation of the micro-image elements,
[0048] Fig. 17 a first view divided vertically into channels,
[0049] Fig. 18 a second view divided vertically into channels,
[0050] Fig. 19 a vertically interleaved two-channel image,
[0051] Fig. 20 a first view divided horizontally into channels,
[0052] Fig. 21 a second view divided horizontally into channels, and
[0053] Fig. 22 a horizontally interleaved two-channel image.
[0054] Structures that are structurally or functionally equivalent are provided with the same reference numerals in the figures.
[0055] Figs. 1 to 3 show a sectional view of an embodiment of a security element 1 with a polymer substrate 2, which has a front side 3 and a back side 4. Furthermore, an exemplary viewing direction B is defined, from which a see-through element is viewed in transmission.
[0056] In Fig. 1, a microimage layer 5 is applied to the back side 4 of the polymer substrate 2. The microimage layer 5 comprises first microimage elements 6 and second microimage elements 8, which are nested within the microimage layer 5. A first camouflage layer 10 is arranged in a layer sequence further away from the back side 4 of the polymer substrate 2. Furthermore, a second camouflage layer 12 is arranged adjacent to the front side 3 of the polymer substrate 2 in the layer sequence, which is followed in the layer sequence opposite to the viewing direction B by a layer of microimage elements 14. A see-through element 15 is formed from the microimage elements 14 and the microimage layer 5, in which the first microimage elements 6 and the second microimage elements 8 are arranged alternately. It presents the viewer with a viewing angle-dependent see-through image.
[0057] Figs. 2 and 3 show a second embodiment of the security element 1, which has the same components as the security element 1 according to Fig. 1; they differ only in the layer sequence. In Fig. 2, the micro-image elements 14 are arranged on the front side 3 of the polymer substrate 2. The first camouflage layer 10 is applied to the back side 4 of the polymer substrate 2, followed by the micro-image layer 5 and the second camouflage layer 12.
[0058] In Fig. 3, the layer sequence in the security element 1 in viewing direction B is: first camouflage layer 10 - polymer substrate 2 - microimage layer 5 - second camouflage layer 12; the microimage elements 14 are embedded in the polymer substrate 2 in the embodiment of Fig. 3.
[0059] In the embodiments according to Figs. 1 to 3, the substrate body consists of a polymer (polymer substrate 2). Possible substrates include, for example, polymer substrates made of BOPP or PET, but also film composite substrates such as film / paper / film or paper / film / paper.
[0060] A preferred, but not explicitly illustrated, embodiment variant consists in metallizing and demetallizing the two film layers surrounding the paper core in film composite substrates in certain areas. In this way, one of the two films contains the microimage elements 6, 8 in the form of metallized and demetallized areas, while the other film provides the microimage elements 6, 8 also in the form of metallized and demeltalized areas. The partial metal layers are preferably located on the inside, i.e., facing the paper core, as they are better protected there from harmful environmental influences. However, they can also be located on the outside, especially since they are preferably protected from external influences by camouflage printing. Together, the two partial metal layers create the see-through element 15 in transmitted light.This structure functions equally when viewed from direction B or when viewed from the opposite side of the security element 1. Preferably, the partially metallized areas of the two foils are provided with an edge area in which a surface density of the metal decreases continuously from the inside to the outside, so that when viewed, no possibly disturbing sharp edge can be seen around the see-through element 15.
[0061] Instead of the partially metallized films, corresponding partially metallized film sections, for example in the form of patches or strips, can also be applied or incorporated onto various conceivable substrates such as polymer, paper or composite materials.
[0062] The microimage layer 5 has two channels, i.e. it consists of the channeled first microimage elements 6 and the channeled second microimage elements 8. The two types of microimage elements 6, 8 are nested in the microimage layer 5. The microimage elements 14 are located in front of the microimage layer 5 in the layer sequence in viewing direction B. Together with the microimage layer 5, they form the see-through element 15. The microimage elements 14 are designed such that a first view 7 and a second view 9 appear depending on the viewing angle; i.e. the see-through element 15 has a dynamic effect. A see-through image can be seen in transmission, which has different views 7, 9 when the viewing angle changes in transmission, thus achieving a dynamic effect. Each view 7, 9 is assigned a specific viewing angle range in which the view 7, 9 can be seen.The viewing angle ranges of the multiple views 7, 9 may overlap or be identical. However, they are preferably different, especially without overlap. This increases the barrier to counterfeiting and improves unaided authentication.
[0063] What is common to all embodiments of Figs. 1 to 3 is that the microimage layer 5 is located between the first camouflage layer 10 and the second camouflage layer 12 in the layer sequence of the security element 1. This enables the camouflage of the transparent image on both sides in reflection by the respective camouflage layer 10, 12, which preferably does not stand out from the surroundings. When viewed in transmission, different first and second views 7, 9 can then be perceived, depending on the viewing angle. The camouflage layers 10, 12 can be printed as a halftone overprint, with a halftone being printed in the same color as the views 7, 9, so that the lighter areas, i.e. the areas without halftone overprint, are easier to recognize in transmission than the halftone print areas. Overprinting with an opaque white ink as an ink-receiving layer is also possible in order to camouflage the transparent image on both sides.If the microimage layer 5 is printed, for example, using reflective ink, e.g., metallic pigment ink, and subsequently overlaid and suppressed with an opaque white ink as a camouflage layer 10, 12, the views 7, 9, and thus the transparent image, will not be recognizable when viewing the security element in reflection, but will be perceived as having a high contrast when viewed in transmission. The opaque white ink can be applied as a raster pattern or as a continuous layer. Overlaying these two variants is also possible.
[0064] The micro-imaging elements 14 can be arranged offset from the micro-image layer 5, as shown in Fig. 3. This allows, for example, sweeping effects, pumping, or morphing to be created. It is also possible for the micro-imaging elements 14 to display additional views.
[0065] Figs. 4 to 8 show the security element 1 in further embodiments, for which a paper substrate 16 is provided as the substrate body. The microimage layer 5 with the first microimage element 6 and the second microimage element 8 is embedded in this paper substrate 16. The see-through element 15 is in turn formed by the microimage elements 14 and the microimage layer 5. It would also be possible for the microimage layer 5 to be located on a front or back side of the paper substrate 16 and the microimage elements 14 to be located on the opposite side.
[0066] In Fig. 4, a layer of micro-imaging elements 14 is arranged in front of the micro-image layer 5 in the viewing direction B.
[0067] In Fig. 5, a film element 18, which comprises the micro-image elements 14, is arranged in front of the micro-image layer 5.
[0068] The embodiment according to Fig. 6 corresponds to the embodiment of Fig. 4, but now additional conventional watermarks 22 are arranged in areas of the paper substrate 16, which are generated by a thickness modulation of the paper substrate 16. Thus, conventional watermarks 22 and the see-through element 15 are arranged on the security element 1 according to Fig. 6.
[0069] The security element 1 in the embodiment of Fig. 7 corresponds to that of the embodiment of Fig. 5, with a blind feature 24 with a covering structure 26 arranged thereon additionally being arranged in areas of the paper substrate 16. Alternatively, for example, a semitransparent thin-film element with a color-changing effect between top view and view can also be used.
[0070] The embodiment of the security element 1 according to Fig. 8 essentially corresponds to the embodiment of Fig. 4, with a first latent image 30 and a second latent image 32 additionally arranged in regions of the paper substrate 16. These are applied by blind embossing or opaque white printing and enable a change of motif by shading. In the embodiments of Figs. 4 to 8, the micro-imaging elements 14 are also arranged in front of the micro-image layer 5 in the viewing direction B, so that a dynamic effect is created by the see-through element 15 formed thereby. Camouflage layers 10, 12 can also optionally be provided if the paper substrate 16 is provided as the substrate body.Camouflage layers with an approximately white color are preferred, which at least partially embed the micro-imaging elements 14 in the form of microlenses, wherein the spaces between the lenses, which anyway contribute little to the imaging, are filled with the white color, while at least the upper sections of the lenses are exposed in order to allow the light required for the imaging to pass through.
[0071] It is possible for the first view 7 to show a subject and the second view 9 not to show a subject, so that, for example, the subject of the first view 7 appears in plan view and disappears when tilted, since the second view 9 appears without a subject when the viewing angle range changes from that of the first view 7 to that of the second view 9. Furthermore, it is possible for the first view 7 to be present as a subject and the second view 9 as a different subject, which results in a flip image being created between these two subjects when tilted. The same is possible if the first view 7 shows a positive image and the second view 9 a negative image, creating a positive / negative flip.
[0072] By supplementing the security element 1 with additional features, as shown in Figs. 6 to 8, the security against counterfeiting can be further increased. Lenticular lenses 34 (= rod lenses), spherical lenses 38, lenses with a regular or irregular outline or 3D profile, or prisms 36 can be used for the micro-imaging elements 14. The lenticular lenses 34 can have 40 to 52 different directions in different partial areas. The spherical lenses 38 could be arranged in different grid geometries, e.g., hexagonal, square, parallelogram-shaped; a chaotic arrangement is also possible. Not explicitly shown, but also possible micro-imaging elements 14 are regularly arranged metallic elements (e.g., metallic thin-film elements such as platelets or stripes, or partially applied metallic pigments).
[0073] In Fig. 9, the micro-imaging elements 14 are shown as lenticular lenses 34 in an isometric view. Fig. 10 shows the micro-imaging elements 14 as prisms 36 in an isometric view 48, and Fig. 11 shows the micro-imaging elements 14 according to Figs. 9 and 10 in a top view. A vertical alignment of the lenticular lenses 34 and prisms 36 is evident.
[0074] With lenses, the nested views 7, 9 can be visible separately for a longer period of time and then switch abruptly, whereas with prisms, a more gradual transition from one view 7, 9 to the other can be achieved. The lenticular lenses 34, like the prisms 36, can have 40 to 52 different directions in different sub-areas.
[0075] Fig. 12 shows the micro-imaging elements 14 as spherical lenses 38 in an isometric view. Figs. 13 and 14 show the spherical lenses 38 in plan view, arranged in different grid geometries. Possible grid geometries include hexagonal, square, parallelogram-shaped, or even chaotic arrangements. In special variants not explicitly shown, Fresnel lenses can also be used as micro-imaging elements 14.
[0076] 15 and 16 show possible different arrangements of lenticular lenses 47 or prisms 36 in the security element 1 in a plan view. In Fig. 15, the security element 1 is divided into a first partial region 40, a second partial region 42, a third partial region 44, and a fourth partial region 45. The plan view shows that the orientations of the micro-imaging elements 14 differ in the partial regions 40 to 46. Lenticular lenses 34 or prisms 36 are considered here as micro-imaging elements 14. These have a longitudinal orientation and are aligned horizontally in regions 40 and 46 and vertically in regions 42 and 44.
[0077] The security element 1 according to Fig. 16 is also divided into a first sub-area 48, a second sub-area 50, and a third sub-area 52. In the first sub-area 48 and the second sub-area 50, the micro-imaging elements 14 (i.e., the lenticular lenses 34 or the prisms 36) are aligned horizontally, and in the third sub-area 52, the micro-imaging elements 14 are aligned vertically. The different alignment of the micro-imaging elements in sub-areas 40 to 52 increases the complexity of the viewing angle-dependent (dynamic) effect and thus the security against counterfeiting.
[0078] Vertically or horizontally channeled means in the following that the first or second micro-image element 7, 9 is each divided into several channels which are aligned vertically or horizontally and nested within each other.
[0079] Fig. 17 shows the first view 7, which is depicted as a vertically channeled first view 54. Fig. 18 shows the second view 9, which is depicted as a vertically channeled second view 56. Fig. 19 shows the interaction of the two vertically channeled views 54, 56 to form a vertically interleaved two-channel image 58. Fig. 20 shows the first view 7 as a horizontally channeled first view 60. Fig. 21 shows the second view 9 as a horizontally channeled second view 62, and Fig. 21 shows the horizontally interleaved two-channel image 64 composed of the two horizontally channeled views 60, 62.
[0080] List of reference symbols
[0081] 1 security element
[0082] 2 Polymer substrate
[0083] 3 Front
[0084] 4 Back
[0085] 5 Microimage layer
[0086] 6 first microimage element
[0087] 7 first view
[0088] 8 second microimage element
[0089] 9 second view
[0090] 10 first camouflage layer
[0091] 12 second camouflage layer
[0092] 14 micro-imaging elements
[0093] 15 Watermark element
[0094] 16 Paper substrate
[0095] 18 slide elements
[0096] 22 conventional watermark
[0097] 24 blind features
[0098] 26 covering structure
[0099] 30 first latent image
[0100] 32 second latent image
[0101] 34 lenticular lenses
[0102] 36 prisms
[0103] 38 spherical lenses
[0104] 40 first sub-area
[0105] 42 second section
[0106] 44 third sub-area 46 fourth sub-area
[0107] 48 first section
[0108] 50 second sub-area
[0109] 52 third section 54 vertically channeled first view
[0110] 56 vertically channeled second view
[0111] 58 vertically interlaced two-channel image
[0112] 60 horizontally channeled first view
[0113] 62 horizontally channeled second view 64 horizontally interleaved two-channel image
[0114] B Viewing direction
Claims
P a te ntsp ü che 1. Security element for a security document, wherein the security element (1) comprises: a substrate body (2, 16) having a front (3) and a back (4), and a see-through element (15) which presents a see-through image to a viewer, characterized in that the see-through element (15) has micro-image elements (14) and first micro-image elements (6) and second micro-image elements (8) arranged alternately in a micro-image layer (5), wherein the micro-image layer (5) is applied to or embedded in the front (3) or back (4) of the substrate body (2, 16) and the micro-image elements (14) image the micro-image elements (6, 8), wherein the first micro-image elements (6) together with the micro-image elements (14) form a first view (7) of the see-through image recognizable from a first viewing angle range,and the second microimage elements (8) together with the micro-imaging elements (14) provide a second view (9) of the transmitted image, recognizable from a second viewing angle range, wherein the microimage elements (6, 8) are arranged such that the views (7, 9) are nested within each other with respect to the microimage layer (5), and the first view (7) differs in its translucency from the second view (9).
2. Safety element according to claim 1, characterized in that the first view (7) and the second view (9) have the same color impression in top view to the naked eye.
3. Security element according to one of the above claims, characterized in that the security element (1) has a first camouflage layer (10) and a second camouflage layer (12), wherein the micro-image layer (5) is located between the first camouflage layer (10) and the second camouflage layer (12).
4. Security element according to claim 3, characterized in that the first camouflage layer (10) and / or the second camouflage layer (12) is a color acceptance layer.
5. Security element according to one of claims 3 or 4, characterized in that the first camouflage layer (10) and / or the second camouflage layer (12) is applied in a grid.
6. Security element according to one of claims 3 to 5, characterized in that the first camouflage layer (10) and / or the second camouflage layer (12) and / or the micro-image layer contains machine-readable substances.
7. Safety element according to one of the above claims, characterized in that the micro imaging elements (14) comprise lenticular lenses (46).
8. Safety element according to one of the above claims, characterized in that the micro imaging elements (14) comprise spherical lenses (50).
9. Safety element according to claim 8, characterized in that the spherical lenses (50) are arranged in different grid geometries in partial areas (52, 54, 56, 58, 60, 62, 64).
10. Safety element according to one of the above claims, characterized in that the micro imaging elements (14) comprise Fresnel lenses.
11. Safety element according to one of the above claims, characterized in that the micro imaging elements (14) comprise prisms (48) which produce a flip effect.
12. Safety element according to one of claims 7 or 11, characterized in that the micro imaging elements (14) are oriented differently in different sub-areas (52, 54, 56, 58, 60, 62, 64).
13. Safety element according to one of the above claims, characterized in that the micro imaging elements (14) and the micro image layer (5) are arranged offset from each other with respect to the surface of the substrate body.
14. Security document with a security element (1) according to one of claims 1 to 13, characterized in that the security element (1) is applied to the security document as a patch or strip.
15. Method for manufacturing a security element for a security document, comprising a substrate body (2, 16) having a front face (3) and a reverse side (4) and a see-through element (15) which allows a viewer to see through it a see-through image, characterized in that the see-through element (15) is provided with micro-imaging elements (14) and first micro-imaging elements (6) and second micro-imaging elements (8) arranged alternately in a micro-imaging layer (5), wherein the micro-imaging layer (5) is applied to or embedded in the front (3) or back (4) of the substrate body (2, 16) and the micro-imaging elements (6, 8) are imaged by the micro-imaging elements (14), wherein a first view recognizable from a first viewing angle (7) of the transmission image is projected through the first micro-image elements (6) together with the micro-imaging elements (14), a second view (9) of the transmission image recognizable from a second viewing angle through the second micro-image elements (8) is imaged together with the micro-image elements (14), the micro-image elements (6, 8) are arranged such that the views (7, 9) are nested within each other with respect to the micro-image layer (5), and the first view (7) differs in its translucency from the second view (9) distinguishes.