Security element for value documents and other documents

Abstract

The invention relates to a security element (100) having a motif layer (10) and an effect layer, in particular for documents (200) such as value documents, identity document, security papers or card-type data carriers. The effect layer (20) is arranged above the motif layer (10) and has an optical effect when viewed under light in the visible range. The effect layer (20) is transparent for infrared light and the motif layer (10) is reflective or absorbing for infrared light, and therefore the motif layer (10) is visible through the effect layer (20) when viewed under infrared light. The motif layer (10) is designed to depict at least one first motif (30). The invention also relates to a document (200) comprising such a security element (100) and to a method for producing a such a document (100).

Description

[0001] SECURITY ELEMENT FOR VALUABLE DOCUMENTS AND OTHER

[0002] DOCUMENTS

[0003] Field of the invention

[0004] The present invention relates to a security element for documents, in particular for value documents, identity documents, security papers or card-shaped data carriers, which combines an optical effect under visible light with a motif visible under infrared light.

[0005] Background of the invention

[0006] Valuable documents such as banknotes, but also identity documents (e.g., identity cards, passports, etc.), as well as other security papers or card-shaped data storage devices, are often equipped with a variety of security features to reliably detect counterfeits. For example, banknotes incorporate security elements with a color-changing effect, with optical effects based on the polarization of light, with optical effects based on birefringence, with holograms, or with other optical effects (generally referred to as "optical effects"). Furthermore, there are also security elements that utilize light in the infrared range (IR light), for example, by making certain contents of such security elements visible or detectable only under such IR light.Color-changing effects and effects based on the polarization or birefringence of light can be realized, for example, using liquid crystal elements. Security features or security elements that utilize IR light, for example, are applied to the respective carrier medium (e.g., a security document) with inks that are either IR-absorbing or IR-reflecting. Description.

[0007] It is an object of the present invention to provide a security element, for example for value documents, identity documents, security documents or card-shaped data carriers, which offers further increased security against forgery.

[0008] This object is achieved by the subject matter of the independent claims. Exemplary embodiments emerge from the dependent claims and the following description.

[0009] According to a first aspect, a security element is provided with a motif layer and an effect layer. The effect layer is arranged above the motif layer and exhibits an optical effect when viewed under light in the visible range. The effect layer is transparent to infrared light (IR light), and the motif layer is reflective or absorbent to infrared light, so that the motif layer becomes visible through the effect layer when viewed under infrared light. The motif layer is designed to depict at least one first motif.

[0010] Such a security element can be used in particular as a counterfeit protection for documents such as valuable documents, identity documents, security papers, or card-shaped data carriers (but in principle also for any other conceivable document), and combines the advantages of security elements based purely on optical effects for visible light with the advantages of security elements based on IR light. In particular, a single security element exhibits both optical effects in the visible spectrum (which are visible to a human user) and effects in the IR spectrum (which are not visible to a human user without additional aids). This increases counterfeit security. Generally, the security element is a multi-layer construction, for example in the form of a strip or a patch.A stripe can be either an applied foil strip or a security thread embedded in the document. For example, on a banknote (or any other carrier medium to be protected with the security element), a stripe can run in one direction across the entire banknote. A patch can be positioned anywhere within the surface of the banknote. In general, it should be noted that the security element is described herein primarily with reference to valuable documents such as banknotes. However, the corresponding explanations are self-explanatory and also apply to all other documents or objects that are or can be provided with the security element.

[0011] The motif layer is based on counterfeit protection using IR light. In particular, the motif layer can be provided as the lowest active layer of the security element and is covered by all other provided layers. One or more bonding layers and / or adhesion layers that may be provided (which are generally applied beneath the motif layer, but can also be arranged between the individual layers and may not be explicitly mentioned herein for the sake of clarity), as described below, are not considered an active layer, since such layers essentially serve to bond the security element to a carrier material or to connect the individual layers to one another, even if these layers naturally also exhibit a certain degree of reflection and absorption capacity.It is also conceivable for a further optional continuous layer to be arranged beneath the motif layer, which is completely reflective for IR light. This can be particularly advantageous if the motif layer is designed as a layer that absorbs IR light, as this increases the reflectivity of the areas surrounding the first motif for IR light and thus, under IR radiation through the motif layer together with such an optional IR light-reflecting layer, a negative image of the first motif represented by the motif layer can be generated. In general, if the motif layer is made of a material that reflects IR light, it will generate a positive image or a negative image of the first motif under IR light (depending on whether the surrounding area or the area of ​​the motif itself is printed).IR light, as used herein, preferably refers in particular to short-wave IR-A radiation in a wavelength range of 780 to 1400 nanometers (nm). However, other IR light wavelength ranges may also be covered.

[0012] For the motif layer to function properly, all layers above it should be transparent / permeable to IR light in both directions, so that absorption and / or reflection by the motif layer (and any optional underlying layer reflecting IR light) is not, or at least not significantly, impaired by these layers. However, at least one of the layers above the motif layer is at least substantially opaque to light in the visible wavelength range (if more than one layer is provided; otherwise, of course, the only layer is opaque to visible light), so that the motif layer or the motif represented by the motif layer is not visible under daylight (i.e., light in the visible wavelength range).However, it is also possible that the layer above the motif layer is at least partially transparent to visible light or at least has corresponding recesses in places so that transparent areas can be created in the security element.

[0013] The effect layer lies above the motif layer and is overall (i.e., if the effect layer itself has a multi-layer structure, as described below, this applies to at least one of these layers) transparent to IR light and at least substantially opaque to daylight. Viewed under daylight, the effect layer produces an optical effect, such as a color shift effect, a polarization effect, a birefringence effect, or any other possible effect that can be produced by selecting suitable materials for the effect layer. Preferably, the effect layer produces a color shift effect, as described below with reference to one embodiment.

[0014] The first motif represented by the motif layer can be text, a pattern, a character, or any other conceivable structure. Since the layers above the motif layer are transparent to IR light, the first motif can then be detected, for example, by illuminating it with incident IR light and capturing the reflection with a corresponding infrared camera.

[0015] The motif layer and the effect layer can, for example, be made up of corresponding colors that are printed on top of each other. Each of the layers is printed with the desired pattern. Depending on the design, the layers can either be printed over the entire surface or just in sections to create the desired motif. Full-surface printing is generally used, particularly for security threads. If the motif layer is, for example, IR-reflective and is intended to display text, either the text itself is printed with an IR-reflective color, i.e. the motif layer is applied with the corresponding structure, or the areas surrounding the text are printed with the IR-reflective color.If the effect layer is to create a full-surface effect, the effect layer is printed / applied over the entire surface of the motif layer (or when printing underneath the motif layer, since the security element is produced / printed in the reverse order from top to bottom, e.g. on a carrier film). In the simplest version, the effect layer forms a continuous layer that lies over the motif layer and covers it completely, and the motif layer forms a discontinuous layer in which, when viewed from above, only the structure of the first motif (or its negative) is covered with the corresponding material of the motif layer. However, the effect layer can also not be printed over the entire surface and, for example, depict a desired motif that is intended to have an optical effect, such as a color shift effect.The effect layer can also be pre-applied to a semi-finished product and then laminated in register with a motif layer printed on a different carrier film, so that the effect layer and the motif layer overlap as desired. The carrier film of the effect layer is then removed.

[0016] According to one embodiment, the effect layer comprises a contrast layer and a liquid crystal layer. The contrast layer is arranged between the liquid crystal layer and the motif layer. The contrast layer forms a background contrast for the liquid crystal layer.

[0017] A liquid crystal layer can, for example, comprise a cholesteric liquid crystal material, a nematic liquid crystal material, and / or a smectic liquid crystal material, which can be present, for example, as a solution or in the form of pigments embedded in a binder matrix. The pigment-in-binder variant forms a coatable "color" and is preferred because such pigments are easier to print and do not place such high demands on the smoothness of the substrate. Printing techniques for the liquid crystal layer (but also for the motif layer and the contrast layer) include, in particular, gravure printing, screen printing, offset printing, flexographic printing, knife coating, or curtain coating. The liquid crystal layer is transparent to IR light. The liquid crystal layer is generally transparent to visible light.

[0018] For example, to create a color shift effect (e.g. red to green or blue to green) or another optical effect, the liquid crystal layer requires a dark, preferably black, background. This background is formed by the contrast layer beneath the liquid crystal layer. The contrast layer is transparent to IR light, so the effect layer as a whole has no effect on the IR light. If the contrast layer is present across the entire surface beneath the liquid crystal layer, the entire surface of the liquid crystal layer can create an optical effect, such as a color shift effect. Alternatively or additionally, the motif layer itself can also serve as a background for the liquid crystal layer, since the material of the motif layer is also visible under daylight.However, if the motif layer alone is used as a background, the image visible with the optical effect would match the IR image.

[0019] Nematic liquid crystalline materials produce a polarization effect. For example, the majority of the liquid crystal layer can be made of a cholesteric liquid crystalline material (which produces a polarization-independent effect (e.g., color-shift effect)), with the exception of areas where an additional pattern, which is only visible with a polarization filter, is intended to appear. Such areas can then comprise a nematic liquid crystalline material. As a result, the pattern formed by the nematic liquid crystalline material in the optical effect is only visible with a polarization filter, providing an additional security feature.

[0020] According to a further embodiment, the contrast layer comprises a printing ink that is transparent to infrared light.

[0021] Such a printing ink can, in principle, be any dark printing ink. However, black is preferred to create maximum contrast.

[0022] According to a further embodiment, the security element further comprises a structured special lacquer layer arranged between the contrast layer and the liquid crystal layer. The special lacquer layer is transparent to infrared light. In areas where a material of the special lacquer layer lies over a material of the contrast layer and / or the motif layer, the special lacquer layer shines through the liquid crystal layer when viewed under visible light.

[0023] The special lacquer layer comprises, in particular, a color material that is partially transparent (translucent) with a whitish color under visible light and that is transparent to IR light. If the special lacquer layer is provided over areas in which either the printing ink of the motif layer 10 and / or the contrast layer 20 is present, the special lacquer layer then appears silver / grey. Since the special lacquer layer also separates the liquid crystal layer from the motif layer and the contrast layer in these areas, and the liquid crystal layer requires a dark background under visible light to develop its effect and is otherwise essentially transparent, the silver color of the special lacquer layer shines through in these areas, thus creating a further, third motif in daylight.In areas where neither the print ink of the motif layer nor the contrast layer is present, the security element also appears transparent, both in reflected and transmitted light. This allows for the implementation of an additional security feature.

[0024] According to a further embodiment, the contrast layer comprises at least one recess which is arranged in a region outside the first motif formed by the motif layer, so that a carrier material arranged under the security element becomes visible through the at least one recess, whereby a second motif is formed by the at least one recess which is visible under visible light.

[0025] Since the liquid crystal layer is essentially transparent to visible light and only produces an optical effect (e.g., color shift effect) with a suitable background, no optical effect occurs in areas where neither the contrast layer nor the motif layer material is present beneath the liquid crystal layer. Thus, with appropriate structuring of recesses in the contrast layer, a second motif can be created that exhibits no optical effect.

[0026] According to a further embodiment, the at least one first motif of the motif layer comprises a machine-readable motif for machine authenticity verification.

[0027] Such a machine-readable motif can, for example, be a specific geometric pattern, a barcode, a QR code, or another machine-readable pattern or code. The machine-readable motif can also have magnetic properties, for example, so that the motif can be detected via magnetic sensors and / or IR sensors. If the machine-readable motif is recognized by an appropriate device (for example, by a money counting machine with IR light and IR camera, or IR sensors in general), the authenticity can be automatically verified and the value of the banknote can be determined.

[0028] According to a further embodiment, the optical effect of the effect layer comprises at least one of a color shift effect, birefringence, and polarization. Preferably, the optical effect is a color shift effect, wherein, when viewed in visible light, the security element appears in a different color depending on the viewing angle.

[0029] According to a further embodiment, the motif layer comprises a color that reflects or absorbs infrared light.

[0030] According to a second aspect, a document is provided which comprises a carrier material and at least one security element according to one of the embodiments described above, which is applied to the carrier material and serves to verify the authenticity and thus to protect the document against forgery.

[0031] According to one embodiment, the document is one of a value document, an identity document, a product security element, a security paper, or a card-shaped data carrier. Furthermore, in addition to the security element, a hologram effect / matte structures or other optical effects can be provided in other areas of the document.

[0032] Valuable documents within the meaning of this disclosure include, in particular, banknotes, shares, bonds, certificates, vouchers, checks, high-value admission tickets, etc. Identity documents are documents at risk of forgery, such as passports and other identification documents. Product security elements include, for example, labels, seals, packaging, and the like. Security paper is the precursor to a valuable document that is not yet fit for circulation and can contain, in addition to the security element, further authenticity features, such as luminescent substances incorporated into the volume. Security paper is typically available in a virtually continuous form and is further processed at a later date. Card-shaped data carriers include, for example, chip cards or other card-shaped documents.

[0033] According to a fourth aspect, a use of a security element according to one of the embodiments described herein as a counterfeit protection on a value document, an identity document, a security paper, or a card-shaped data carrier is provided.

[0034] Short description of the characters

[0035] Fig. 1 shows a security element with an effect layer and an underlying motif layer in a view under visible light (left) and under infrared light (right), whereby the motif layer forms a first motif as text.

[0036] Fig. 2 shows the security element from Fig. 1, wherein the motif layer has a machine-readable motif in addition to the first motif.

[0037] Fig. 3 shows a layer structure of the security elements from Figs. 1 and 2 after application to a document.

[0038] Fig. 4 shows the layer structure of Fig. 3 before application to the document.

[0039] Fig. 5 shows a security element with an effect layer and a motif layer, similar to Fig. 1, with a second motif visible under visible light being additionally present.

[0040] Fig. 6 shows the layer structure of the security element from Fig. 5 before application to a document.

[0041] Fig. 7 shows a document in the form of a banknote with two security elements.

[0042] Fig. 8 shows a security element similar to Figs. 5 and 6, with the addition of a third, silver-colored motif in the daylight view, which is formed by an additional special lacquer layer.

[0043] Fig. 9 shows schematically the layer structure of the security element of Fig. 8. Fig. 10 shows another security element with a polarized motif which is only visible under a polarization filter.

[0044] Detailed description of exemplary embodiments

[0045] The representations in the figures are schematic and not to scale. Where the same reference symbols are used in different figures in the following description, they refer to identical or similar elements. Identical or similar elements may also be designated by different reference symbols.

[0046] Fig. 1 shows a security element 100 in a first embodiment. The security element 100 is illustrated in a daylight view 1 and in an infrared light view 2 (IR light view 2). The daylight view 1 refers to viewing under visible light, i.e., under light in the wavelength range visible to humans. The IR light view 2 refers to viewing under infrared light (IR light), i.e., irradiation with IR light and detection of the reflected IR light, for example, with an infrared camera. The security element 100 has an effect layer 20 with a liquid crystal layer 23 on top and a contrast layer 21 (see Figs. 3 and 4). The effect layer 20 covers a motif layer 10, which has a first motif 30, here in the form of text. The first motif 30 is only visible when viewed under IR light.For this purpose, the effect layer 20 is at least partially transparent (ie translucent) to infrared light, preferably completely transparent to IR light, but opaque to daylight.

[0047] In the daylight view 1, the security element 100 in this embodiment displays a full-surface optical effect (in the configuration shown, a color shift effect) as described herein. However, other optical effects are also possible. In the IR light view 2, the motif layer 10 is visible. In the configuration shown, the first motif 30 is a text "PL 25", which is printed in the motif layer 10 with an IR-reflecting ink and is thus visible under IR light. However, any other first motif 30 can also be provided. Fig. 2 shows the security element 100 of Fig. 1 in a slightly modified form. In the daylight view 1, the security element 100 of Fig. 2 is identical to the security element of Fig. 1. However, in addition to the first motif 30, the motif layer 10 has a machine-readable motif 31 in the shape of a square, which is thus also visible under IR light.The machine-readable motif 31 may also have other suitable shapes, such as barcodes, QR codes, geometric shapes, etc., which can be recognized and evaluated by a machine with appropriate sensors.

[0048] 3 and 4 show a schematic layer structure of the security elements 100 of FIGS. 1 and 2. Fig. 3 shows the layer structure before the respective security element 100 has been applied to a document 200 (not shown, cf. Fig. 7). Fig. 4 shows the layer structure after the security element 100 has been applied to the document 200 (i.e., to a carrier material 210 of the document 200). The security element 100 has an effect layer 20 as the uppermost layer, which in turn has the previously described liquid crystal layer 23 and a contrast layer 21. Both the liquid crystal layer 23 and the contrast layer 21 are transparent to IR light. The contrast layer 21 is also not transparent to visible light. The liquid crystal layer 23 is transparent to visible light.The contrast layer 21 serves as a background for the liquid crystal layer 23 since, as described above, the liquid crystal layer 23 only exhibits a color shift effect when a dark background (preferably black) is present. Since a full-surface color shift effect is implemented in Figs. 1 and 2, both the liquid crystal layer 23 and the contrast layer 21 are printed over their entire surface. In addition, the liquid crystal layer 23 is preferably printed at least somewhat wider than the contrast layer 21 so that the contrast layer 21 cannot be recognized in daylight without the liquid crystal layer 23 since the liquid crystal layer 23 does not exhibit a color shift effect in places without a dark background. The motif layer 10, which forms the motif visible under IR light, lies beneath the contrast layer 21.The motif layer 10 preferably comprises a black color ink that is either reflective or absorbent for IR light. If the color ink of the motif layer 10 is reflective, the color in the motif layer 10 is printed according to the first motif 30 (Fig. 1) and / or the machine-readable motif 31 (Fig. 2), and a positive image of these motifs is visible under IR light. The color in the motif layer 10 can be printed according to a negative image and / or a positive image of the first motif 30 and / or the machine-readable motif 31.

[0049] In Fig. 3, the security element 100 is already applied to a document 200. For this purpose, a primer layer 50 was previously applied beneath the motif layer 10 for better bonding to an adhesion layer 60, and the adhesion layer 60 was applied beneath the primer layer 50 (for example, an adhesive layer such as a heat-sealing lacquer layer 60). The security element 100 is then attached to the carrier material 210 of the document 200 with the adhesion layer 60. Furthermore, a carrier film (not shown), for example, a PET carrier film, can also be provided between the motif layer 10 and the primer layer 50 or between the effect layer 20 and the motif layer 10.

[0050] In Fig. 4, the security element 100 has not yet been applied to the document 200. Here, a carrier film 220 (for example, a polyethylene terephthalate carrier film 220, PET carrier film 220) is present above the liquid crystal layer 23. During production, the security element 100 is printed step by step in reverse order from the carrier film 220, starting with layers 23, 21, 10, and then layers 50 and 60 are applied. During production, the security element 100 thus lies with the top side shown in Fig. 4 facing down. Subsequently, the security element 100 is applied to the carrier material 210 by means of the adhesive layer 60, and the carrier film 220 is removed / peeled off.

[0051] 5 and 6 show an alternative configuration of the security element 100. In Fig. 5, the security element is again shown in a plan view, both in the daylight view 1 and in the IR light view 2. Fig. 6 again shows the layer structure of the security element 100 of Fig. 5. The layer structure is again shown before application to a document 200, i.e. with the carrier film 220 but without the carrier material 210 of the document 200. Features that correspond to Figs. 1 to 4 are not repeated for the sake of brevity. In contrast to Figs. 1 to 4, the contrast layer 21 in Figs. 5 and 6 has cutouts 22 that are arranged outside the area printed on the motif layer 10.Since the liquid crystal layer 23 only produces an optical effect (e.g., a color shift effect) when a dark background is present, no such optical effect is visible in the area of ​​the recesses 22 in the daylight view 1. The recesses 22 are shaped such that a second motif 40 is formed by the areas without an optical effect (in Fig. 5, the letters "PL"), which is visible in daylight. The first motif 30 (in Fig. 1, number "25") of the motif layer 10 is, in turn, only visible in the IR light view 2.

[0052] Fig. 7 shows a document 200 in the form of a banknote 200. The banknote 200 comprises a first security element 100 in the form of a patch-shaped security element 110 and a second security element 100 in the form of a strip-shaped security element 120. The security elements 110, 120 are arranged on a carrier material 210 of the banknote 200, which represents the paper of the banknote 200. The strip-shaped security element 100, 120 extends in a vertical direction over the entire extent. The patch-shaped security element 100, 110 is freely placed on the carrier material 210. The patch-shaped security element 110 is configured in Fig. 7 according to the embodiment of Fig. 5.Although the strip-shaped security element 120 is shown as a security element with three regions (for example in the form of a security thread incorporated in the document or as an applied foil strip) with an effect layer 20 and an underlying motif layer 10 (not shown), it should be recognized that the security element 100 can in principle have any number of such regions and, in particular, can comprise a contiguous such region with any number of motifs 30, 40 over the entire extent. Furthermore, it should be recognized that the security elements 100 can have any shape. A foil or a patch as well as an additional security thread can have either the same color shift effect or a different color shift effect.In general, multiple security elements 100 can be provided on a document 200, which can be configured identically or differently. Additionally, other security elements, for example, with a hologram effect / matte structures or any other optical effect, can also be provided on the document 200. Furthermore, the banknote 200 shown is only an example of a document 200 equipped with the security element 100, and the security element 100 can in principle be used on any other suitable document 200.

[0053] Figures 8 and 9 show an alternative configuration of a security element 100.

[0054] Fig. 8 shows the security element 100 again in a daylight view 1 and in an IR light view 2 (here in two variants).

[0055] Fig. 9 shows a schematic view of the corresponding layer structure prior to application to a document 200. The configuration shown is similar to the configuration in Figs. 5 and 6. However, the security element 100 here additionally comprises a special lacquer layer 70, which is arranged between the liquid crystal layer 23 and the contrast layer 21 of the effect layer 20 and comprises a color material that is also transparent or at least partially transparent (translucent; i.e. partially translucent) to IR light. As with the security elements 100 of Figs. 1 to 6, all layers 23, 70, 21 arranged above the motif layer 10 are thus transparent to IR light. The first motif 30 as well as the machine-readable motif 31 according to the alternatives shown in Fig. 8 can thus be formed in the same way as with reference to Figs.1 to 6, in particular by appropriately applying a colored paint which is either reflective or absorbing for IR light.

[0056] In addition to the transparency / translucency of the additional special lacquer layer 70 under IR light, the special lacquer layer 70 is translucent under visible light and has a white or whitish-silver color tone.

[0057] The liquid crystal layer 23, in turn, is inherently transparent under visible light and only exhibits a color shift effect when a dark background color or layer (such as the contrast layer 21 or the motif layer 10) lies beneath the liquid crystal layer 23 without another intervening layer (such as the special lacquer layer 70). The special lacquer layer 70, in turn, has overlapping areas with both the motif layer 10 and the contrast layer 21 (all areas outside of the area 80 in which neither the motif layer 10 nor the contrast layer 21 is present). In this overlapping area, the viewer sees an overall silvery color in the visible wavelength range. The printing inks / color inks of the motif layer 10 and / or the contrast layer 21 are located behind the color material of the special lacquer layer 70 in the overlapping areas in the viewing direction.There, the interaction of the special lacquer layer 70 with the contrast layer 20 and / or motif layer 10 results in an overall silver color tone for the observer in the visible wavelength range of electromagnetic radiation or visually.

[0058] The phrase that a printing ink / color ink "in itself" has a certain color tone means, within the meaning of this disclosure, that the respective printing ink has this color tone on its own, i.e., without interaction with another printing ink. Thus, if only one of the respective printing inks / color inks were arranged on the substrate, this printing ink / color ink would have this color tone. In Figs. 8 and 9, two printing inks transparent to IR light are combined, with the first printing ink being opaque and the second printing ink being translucent in the visible wavelength range, and with the printing ink of the special lacquer layer 70 with the white color tone being applied in the viewing direction above the dark or black printing ink of the contrast layer 21 and / or motif layer 10. The combination of the two printing inks results in a total of 10% light transmission in the overlap area for the observer in the daylight view 1 (cf. Fig.8) a silver hue, since in this area, due to the lack of a dark background, the liquid crystal layer 23 is essentially transparent to visible light and exhibits no or at least a significantly reduced color shift effect. This creates a further or third motif 41 in the daylight view 1 that has a silver hue.

[0059] Since, in addition, both the liquid crystal layer 23 and the special lacquer layer 70 require a dark background to achieve their respective effect, by providing regions 80 in which neither the contrast layer 21 nor the motif layer 10 is present (or in which the respective printing inks of these layers are not present), which in the daylight view 1 is essentially transparent both in incident light and in transmitted light (essentially because the special lacquer layer 70 itself is "only" translucent and the carrier material 210 of the document 200, to which the security element 100 is applied, is not completely transparent. However, the region 80 can still be clearly recognized).

[0060] Fig. 10 shows a further embodiment of a security element in daylight view 1, in which a polarized motif 42, here in the form of the number "25," is present. Such a polarized motif 42 can be created, for example, by manufacturing the regions of the liquid crystal layer surrounding the polarized motif 42 from a cholesteric liquid crystalline material and the region of the polarized motif 42 from a nematic liquid crystalline material. As a result, as described above, the polarized motif 42 is only visible under a polarization filter.

[0061] List of reference symbols

[0062] 1 daylight view

[0063] 2 Infrared light view (IR light view)

[0064] 10 motif layer

[0065] 20 effect layer

[0066] 21 Contrast layer

[0067] 22 recess

[0068] 23 Liquid crystal layer

[0069] 30 first motif

[0070] 31 machine-readable motif

[0071] 40 second motif

[0072] 41 third motif

[0073] 42 polarized motif

[0074] 50 Adhesion promoter layer (primer layer)

[0075] 60 adhesion layer, heat seal lacquer layer

[0076] 70 special lacquer layer

[0077] 80 area

[0078] 100 security elements

[0079] 110 Patch-shaped security element

[0080] 120 strip-shaped security element

[0081] 200 document, security document, banknote

[0082] 210 carrier material

[0083] 220 carrier film, polyethylene terephthalate carrier film (PET carrier film)

Claims

Patent claims 1. A security element (100), comprising: a motif layer (10); and an effect layer (20); wherein the effect layer (20) is arranged above the motif layer (10) and has an optical effect when viewed under light in the visible range; wherein the effect layer (20) is transparent to infrared light and the motif layer (10) is reflective or absorbent to infrared light, such that the motif layer (10) becomes visible through the effect layer (20) when viewed under infrared light; and wherein the motif layer (10) is designed to display at least one first motif (30).

2. The security element (100) according to claim 1, wherein the effect layer (20) comprises a contrast layer (21) and a liquid crystal layer (23); wherein the contrast layer (21) is arranged between the liquid crystal layer (23) and the motif layer (10). wherein the contrast layer (21) forms a background contrast for the liquid crystal layer (23) and thus enables the optical effect.

3. Security element (100) according to claim 2, wherein the contrast layer (21) comprises a color transparent to infrared light.

4. Security element (100) according to one of claims 2 or 3, further comprising a structured special lacquer layer (70) arranged between the contrast layer (21) and the liquid crystal layer (23); wherein the special lacquer layer (70) is transparent to infrared light; and wherein the special lacquer layer (70) shines through the liquid crystal layer (23) in regions in which a material of the special lacquer layer (70) lies above the material of the contrast layer (21) and / or the motif layer (10) when viewed under visible light.

5. Security element (100) according to one of claims 2 to 4, wherein the contrast layer (21) comprises at least one cutout (22) which is arranged in a region outside the first motif (30) formed by the motif layer (10), so that a carrier material (210) arranged under the security element (100) becomes visible through the at least one cutout (22), whereby a second motif (40) is formed by the at least one cutout (22) which is visible under visible light.

6. Security element (100) according to one of the preceding claims, wherein the at least one first motif (30) of the motif layer (10) comprises a machine-readable motif (31) for machine authenticity verification.

7. Security element (100) according to one of the preceding claims, wherein the optical effect of the effect layer comprises at least one of a color shift effect, birefringence and polarization.

8. Security element (100) according to one of the preceding claims, wherein the motif layer (10) comprises a color that reflects or absorbs infrared light.

9. A document (200) comprising: a carrier material (210); and at least one security element (100) according to one of the preceding claims, which is applied to the carrier material (210) and serves to verify the authenticity and thus to protect the document (200) against forgery.

10. Document (200) according to claim 9, wherein the document (200) is one of a value document, an identity document, a security paper or a card-shaped data carrier.

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