DE102018003603A1 - Security element, disk and usage - Google Patents

Abstract

The invention relates to a security element for securing a value document, security document or a valuable article, with predetermined areas that appear to the viewer in a diffuse illumination, especially when viewed in daylight, in a first visually recognizable color and in the illumination with a punctiform light source, in particular when viewed with the flashlight of a smartphone in a darkened room, appear in a second visually recognizable color and form markings in the form of patterns, characters or a coding, which are not recognizable to the viewer in diffuse lighting, especially when viewed in daylight are visible only when illuminated with a point light source, in particular when viewed with the flashlight of a smartphone in a darkened room, the security element having a layer with a reflective microstructure and the Bet a semi-transparent functional layer facing laterally, and the semitransparent functional layer is such that it has the first visually recognizable color when viewed in reflected light and has the second visually recognizable color when viewed in transmitted light.

Description

The invention relates to a security element and a data carrier comprising the security element, in particular a value document, security document or a valuable article. The invention further relates to the use of the security element for securing a data carrier provided with a retroreflective structure, in particular a license plate, a traffic sign, a billboard, or safety clothing.

Securities and security documents, such as banknotes, valuables or ID documents, but also other valuables, such as branded goods, are often provided with security elements for the purpose of protection, which allow a verification of the authenticity of the data carrier and at the same time serve as protection against unauthorized reproduction. The security elements may, for example, be in the form of a security thread embedded in a banknote, a patch applied to the banknote, e.g. a transfer element or a cover sheet suitable for covering an opening in the banknote, a security strip or else in the form of a feature area applied directly to a value document.

A special role in the authenticity assurance play security elements, the viewing angle-dependent visual effects show, as they can not be reproduced even with the latest copiers. In the prior art it is known, for example, to represent objects by means of a reflecting microstructure, which cause movement effects when tilting and / or rotating the value document provided with the security element. Exemplary is on the WO 2015/078572 A1 and WO 2016/180522 A1 directed. The reflective microstructure includes microreflectors formed in a pattern so as to produce a planar security element having a plurality of pixels each comprising at least one microreflector (ie, at least one optically effective facet). The two-dimensional form of the security element defines a main plane. The micro-reflectors are oriented so that the object causes a movement effect when tilting and / or rotating the security element, which is related to the main plane. Instead of a movement effect, the objects can also show a tilting effect. From the WO 2011/066990 A2 a three-dimensional appearing object is known, which appears to the viewer in front of or behind the main plane arched form. When the security element is tilted, the position of the object relative to the main plane remains unchanged.

The invention has for its object to provide a security element with higher security against counterfeiting.

The object is achieved by the feature combinations defined in the independent claims. Further developments of the invention are the subject of the dependent claims.

Summary of the invention

1. 1. (First aspect of the invention) Security element for securing a value document, security document or a valuable article, with predetermined areas that the viewer in diffuse lighting, especially when viewed in daylight, appear in a first visually recognizable color and lighting with a point light source, in particular when viewed with the flashlight of a smartphone in a darkened room, appear in a second visually recognizable color and form markings in the form of patterns, characters or a coding that the viewer in diffuse lighting, especially when viewed in the Daylight, are not visible and only in the illumination with a point light source, especially when viewed with the flashlight of a smartphone in a darkened room, recognizable, the security element is a layer with a reflective microstructure and a d the semitransparent functional layer facing the observer and the semitransparent functional layer is such that it has the first visually recognizable color when viewed in reflected light and has the second visually recognizable color when viewed in transmitted light.
2. 2. (Preferred embodiment) Security element according to clause 1 wherein the reflective microstructure is in the form of a retroreflective structure with triangular or quadrangular cube corners, or in the form of a micro-glass bead-based retroreflective structure, wherein the reflective microstructure is preferably provided with a metallization, more preferably with a specular metal coating.
3. 3. (Preferred embodiment) Security element according to clause 1 , wherein the reflective microstructure in the form of a mosaic of a plurality of reflective mosaic elements, which are characterized by the parameters size, outline, relief shape, reflectivity and spatial orientation and are such that the markings in the form of patterns, characters or a Coding when tilting the security element have a dynamic movement effect by different groups of mosaic elements with different characteristic parameters reflect incident light into different spatial areas.
4. 4. (Preferred embodiment) Security element according to one of the clauses 1 to 3 wherein the layer is provided with a reflective microstructure in the form of a metallized embossing lacquer layer.
5. 5. (Preferred embodiment) Security element according to one of the clauses 1 to 4 in which the markings are formed in the form of patterns, characters or a coding by recesses in an opaque layer which is arranged between the semitransparent functional layer and the layer with the retroreflective structures, the opaque layer being in particular a metallization or a color layer.
6. 6. (Preferred embodiment) Security element according to clause 5 with reference to clause 3 wherein the recesses in the opaque layer form first markings in the form of patterns, characters or an encoding, and the reflective microstructure in the form of a mosaic of a multiplicity of reflective mosaic elements form second markings in the form of patterns, characters or an encoding, the second marks preferably at least partially adapted to the first markings.
7. 7. (Preferred embodiment) Security element according to one of the clauses 1 to 6 in which the semitransparent functional layer has a multilayer structure with two semitransparent metallic layers and a dielectric layer arranged between the two semitransparent metallic layers.
8. 8. (Preferred embodiment) Security element according to clause 7 wherein the two semitransparent metallic layers are independently formed of a metal and the metal is selected from the group consisting of Al, Ag, Ni, Cr, Cu, Au, Si and an alloy of one or more of the aforementioned elements; dielectric layer is an SiO ₂ layer, a ZnO layer, a ZnS layer, an Al ₂ O ₃ layer, a TiO ₂ layer, a layer of a nitride or oxynitride of any of Si, Zn, Al or Ti or a MgF ₂ layer or, for example, technically available, nitrocellulose layer.
9. 9. (Preferred embodiment) Security element according to clause 7 or 8th wherein the two semitransparent metallic layers are independently selected from Al or Ag and the dielectric layer is an SiO ₂ layer.
10. 10. (Preferred Embodiment) Security element according to one of the clauses 1 to 6 , wherein the semitransparent functional layer is obtainable by printing technology by means of an effect pigment composition.
11. 11. (Preferred embodiment) Security element according to one of the clauses 1 to 6 , wherein the semitransparent functional layer has a multilayer structure based on interference layers consisting only of transparent layers, wherein the multilayer structure is based in particular on, preferably alternating, layers of TiO ₂ , Al ₂ O ₃ or other dielectrics.
12. 12. (Preferred Embodiment) Security element according to one of the clauses 1 to 6 wherein the semitransparent functional layer is based on a plasmonic color filter and in particular based on two-dimensional periodic nanostructures. Plasmonic color filters based on two-dimensional periodic nanostructures are known, for example, from US Pat DE 10 2011 101 635 A1 known.
13. 13. (Preferred Embodiment) Security element according to one of the clauses 1 to 12 In the case of diffuse illumination, in particular when viewed in daylight, the predetermined areas appear golden to the observer and appear bluish when illuminated with a punctiform light source, in particular when viewed with the flashlight of a smartphone in a darkened room.
14. 14. (Preferred Embodiment) Security element according to one of the clauses 1 to 13 wherein the security element has the following structure:
    • - adhesive layer;
    • Layer with a reflective microstructure;
    • Optionally, an opaque layer with recesses in the form of patterns, characters or an encoding;
    • - semitransparent functional layer;
    • - Carrier film.
15. 15. (Preferred embodiment) Security element according to one of the clauses 1 to 13 wherein the security element has the following structure:
    • - adhesive layer;
    • Layer with a reflective microstructure;
    • - Carrier film;
    • - semitransparent functional layer;
    wherein either an opaque layer with recesses in the form of patterns, characters or a coding is optionally arranged either between the layer having the reflective microstructure and the carrier film or between the carrier film and the semitransparent functional layer.
16. 16. (Preferred embodiment) Security element according to clause 14 or 15 in which an embossing lacquer layer with an embossed relief is arranged between the carrier foil and the semitransparent functional layer, wherein the embossed relief is in particular a relief having micro and / or nanostructures.
17. 17. (Second aspect of the invention) Data carrier, in particular a value document, security document or a valuable article, comprising the security element according to one of the clauses 1 to 16 ,
18. 18. (Third aspect of the invention) A security element for securing a data carrier provided with a retroreflective structure, wherein the security element has predetermined areas which appear to the observer in diffuse illumination, in particular when viewed in daylight, in a first visually recognizable color and in which Lighting with a point light source, especially when viewed with the flashlight of a smartphone in a darkened room, appear in a second visually recognizable color and form markings in the form of patterns, characters or a coding, which are for the viewer in diffuse lighting, in particular the observation in daylight, are not recognizable and only in the lighting with a point light source, especially when viewed with the flashlight of a smartphone in a darkened room, recognizable, the security element one for gluing the Security element with the hedged, provided with a retroreflective structure data carrier suitable adhesive layer and the viewer facing semitransparent functional layer and the semitransparent functional layer is such that it has the first visually recognizable color when viewed in incident light and when viewed in transmitted light, the second has visually recognizable color. It is preferred that the retroreflective structure of the data carrier is based on a reflective microstructure, in particular in the form of a retroreflective structure with triangular or square cube corners, or in the form of a microglass-based retroreflective structure, the reflective microstructure preferably having a metallization preferably provided with a reflective metal coating.
19. 19. (Preferred embodiment) Security element according to clause 18 in which the markings are formed in the form of patterns, characters or a coding by recesses in an opaque layer which is arranged between the semitransparent functional layer and the adhesive layer.
20. 20. (Preferred Embodiment) Security element according to one of the clauses 18 or 19 in which the semitransparent functional layer has a multilayer structure with two semitransparent metallic layers and a dielectric layer arranged between the two semitransparent metallic layers.
21. 21. (Preferred embodiment) Security element according to clause 20 wherein the two semitransparent metallic layers are independently formed of a metal and the metal is selected from the group consisting of Al, Ag, Ni, Cr, Cu, Au, Si and an alloy of one or more of the aforementioned elements; dielectric layer is an SiO ₂ layer, a ZnO layer, a ZnS layer, an Al ₂ O ₃ layer, a TiO ₂ layer, a layer of a nitride or oxynitride of any of Si, Zn, Al or Ti or a MgF ₂ layer or, for example, technically available, nitrocellulose layer.
22. 22. (Preferred embodiment) Security element according to clause 20 or 21 wherein the two semitransparent metallic layers are independently selected from Al or Ag and the dielectric layer is an SiO ₂ layer.
23. 23. (Preferred embodiment) Security element according to one of the clauses 1 to 6 , wherein the semitransparent functional layer is obtainable by printing technology by means of an effect pigment composition.
24. 24. (Preferred embodiment) Security element according to one of the clauses 18 or 19 in which the semitransparent functional layer has a multilayer structure based on interference layers consisting only of transparent layers, the multilayer structure being particularly preferred alternating, layers of TiO ₂ , Al ₂ O ₃ or other dielectrics based.
25. 25. (Preferred embodiment) Security element according to one of the clauses 18 or 19 wherein the semitransparent functional layer is based on a plasmonic color filter and in particular based on two-dimensional periodic nanostructures. Plasmonic color filters based on two-dimensional periodic nanostructures are known, for example, from US Pat DE 10 2011101 635 A1 known.
26. 26. (Preferred embodiment) Security element according to one of the clauses 18 to 25 In the case of diffuse illumination, in particular when viewed in daylight, the predetermined areas appear golden to the observer and appear bluish when illuminated with a punctiform light source, in particular when viewed with the flashlight of a smartphone in a darkened room.
27. 27. (Preferred Embodiment) Security element according to one of the clauses 18 to 26 wherein the security element has the following structure:
    • - adhesive layer;
    • Optionally, an opaque layer with recesses in the form of patterns, characters or an encoding;
    • - semitransparent functional layer;
    • - Carrier film.
28. 28. (Fourth aspect of the invention) A data carrier provided with a retroreflective structure, in particular a license plate, a road sign, a billboard, or safety clothing, comprising the security element according to one of the clauses 18 to 27 ,
29. 29. (Fifth Aspect of the Invention) Use of the security element according to one of the clauses 18 to 27 for securing a data carrier provided with a retroreflective structure, in particular a license plate, a road sign, a billboard or advertising space, or safety clothing.

Detailed description of the invention

An observation in reflected light in the sense of this invention is a lighting of the respective object from one side and a viewing of the object from the same side.

A reflection in the transmitted light in the sense of this invention is an illumination of the respective object from one side and a viewing of the object from the opposite side.

Diffuse lighting refers to diffuse light, which illuminates the scene evenly and with little or no shadow. Diffused light is produced by areal light sources.

In accordance with the present invention, attractive security features are provided that are useful when changing viewing in diffused lighting, particularly when viewed in daylight, on the one hand, and when illuminated with a point light source, particularly when viewed with the flashlight of a smartphone in a darkened room. on the other hand have an interesting color change, eg a change in color from gold in diffuse lighting to blue in lighting with a point light source. Incidentally, the same appearance as when viewed with a point light source, especially when viewed with the flashlight of a smartphone in a darkened room, offers the viewer when viewing a photograph taken with a smartphone camera with the flash on.

According to a first variant, for the layer with a reflective microstructure, a reflective microstructure in the form of a mosaic of a multiplicity of reflecting mosaic elements, characterized by the parameters size, outline shape, relief shape, reflectivity and spatial orientation, can be used, such that the Markers in the form of patterns, characters or coding when tilting the security element have a dynamic movement effect in that different groups of mosaic elements with different characteristic parameters reflect incident light into different spatial areas. The mosaic elements preferably have a lateral dimension of less than 30 μm and below the resolution limit of the eye. It is preferred that markings in the form of patterns, characters or a coding are formed as a motif in the form of an embossed structure in an embossing lacquer layer, the embossing structure having raised embossing elements with surfaces of different orientation. The embossing structure here consists of a reflective microstructure in the form of a mosaic of a multiplicity of reflecting mosaic elements, which are characterized by the parameters size, outline shape, relief shape, reflectivity and spatial orientation. Reflective microstructures for displaying objects that tilt and / or rotate of the provided with the security element Value documents cause movement effects are known in the art, see eg the fonts WO 2015/078572 A1 . WO 2016/180522 A1 and WO 2011/066990 A2 , The reflective microstructure may preferably produce a planar security element having a plurality of pixels, each comprising at least one reflective mosaic element, ie at least one optically effective facet. The planar shape of the security element defines a main plane. The reflective mosaic elements are preferably oriented so that the object causes a movement effect when tilting and / or rotating the security element, which is related to the main plane. Instead of a movement effect, the objects can also show a tilting effect. From the WO 2011/066990 A2 a three-dimensional appearing object is known, which appears to the viewer in front of or behind the main plane arched form. When tilting the security element, the position of the object remains unchanged to the main level.

For the layer with a reflective microstructure, according to a second variant, a retroreflective structure can be used. Retroreflective structures, for example, reflect the light of vehicle headlights in the direction of the driver to increase visibility, are known in the art and can be based for example on triangular or square cube corners or on micro glass beads, see for example the documents US 4763985 A . US 20090300953 A1 . WO 2014/117086 A1 . US 6413615 B2 and US 4478769 A , Cube-corner structures are based, for example, on embossed relief structures that are mirrored with a reflective metal layer. The cube-corner structures may be present in particular with triangular or quadrilateral surfaces. Conveniently, the relief structures are embossed in a plastic material or in a UV varnish.

The security element according to the invention is expediently provided on the basis of a carrier film such as polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polypropylene (PP), polyethylene (PE), polycarbonate (PC) or the like.

The layer having the retroreflective structure may suitably be in a layer thickness in a range of 10 μm to 200 μm, preferably in a range of 30 μm to 150 μm, and more preferably in a range of 40 μm to 150 μm. The height of the retroreflective structure, in particular of the triangular or quadrangular cube corners, is expediently at least 10 μm, preferably at least 30 μm, and expediently less than 200 μm, preferably less than 150 μm.

The semitransparent functional layer, on the other hand, has different hues when viewed in reflected light on the one hand and when viewed in transmitted light on the other hand. The two different shades are, for example, complementary colors. Such a semitransparent functional layer is in particular a so-called Fabry-Perot thin-film element based on a multilayer construction with two semitransparent metallic layers and a dielectric layer arranged between the two semitransparent metallic layers. Such a multi-layered structure, which appears golden when viewed in reflected light and shows a blue hue when viewed in transmitted light, is for example from the WO 2011/082761 A1 known.

• - die beiden semitransparenten metallischen Schichten werden bevorzugt von Al oder Ag gewählt; die dielektrische Schicht ist insbesondere eine SiO₂-Schicht oder eine MgF₂-Schicht, bevorzugt eine SiO₂-Schicht;
• - im Falle, dass jede der beiden semitransparenten metallischen Schichten auf Al beruht, liegt die jeweilige bevorzugte Schichtdicke in einem Bereich von 5 nm bis 20 nm, insbesondere bevorzugt in einem Bereich von 10 nm bis 14 nm; die dielektrische SiO₂-Schicht hat vorzugsweise eine Schichtdicke in einem Bereich von 50 nm bis 600 nm, weiter bevorzugt in einem Bereich von 80 nm bis 260 nm und insbesondere bevorzugt in einem Bereich von 210 nm bis 260 nm, wobei die Bereiche von 80 nm bis 100 nm und von 210 nm bis 240 nm speziell für die Bereitstellung eines Gold/Blau-Farbwechsels besonders bevorzugt werden;
• - im Falle, dass jede der beiden semitransparenten metallischen Schichten auf Ag beruht, liegt die jeweilige bevorzugte Schichtdicke in einem Bereich von 15 nm bis 30 nm, insbesondere bevorzugt von 15 nm bis 25 nm; die dielektrische SiO₂-Schicht hat vorzugsweise eine Schichtdicke in einem Bereich von 50 nm bis 600 nm, weiter bevorzugt in einem Bereich von 80 nm bis 260 nm und insbesondere bevorzugt in einem Bereich von 210 nm bis 260 nm, wobei die Bereiche von 80 nm bis 100 nm und von 210 nm bis 240 nm speziell für die Bereitstellung eines Gold/Blau-Farbwechsels besonders bevorzugt werden.

Suitable multi-layered structures with two semitransparent metallic Layers and a dielectric layer arranged between the two semitransparent metallic layers preferably have the following physical properties:

• the two semitransparent metallic layers are preferably selected from Al or Ag; the dielectric layer is in particular an SiO ₂ layer or an MgF ₂ layer, preferably an SiO ₂ layer;
• in the case where each of the two semitransparent metallic layers is based on Al, the respective preferred layer thickness is in a range of 5 nm to 20 nm, particularly preferably in a range of 10 nm to 14 nm; the dielectric SiO ₂ layer preferably has a layer thickness in a range of 50 nm to 600 nm, more preferably in a range of 80 nm to 260 nm and particularly preferably in a range of 210 nm to 260 nm, the ranges of 80 nm up to 100 nm and from 210 nm to 240 nm are especially preferred for providing a gold / blue color change;
• in the case where each of the two semitransparent metallic layers is based on Ag, the respective preferred layer thickness is in a range from 15 nm to 30 nm, particularly preferably from 15 nm to 25 nm; the dielectric SiO ₂ layer preferably has a layer thickness in a range of 50 nm to 600 nm, more preferably in a range of 80 nm to 260 nm and particularly preferably in a range of 210 nm to 260 nm, the ranges of 80 nm to 100 nm and from 210 nm to 240 nm are especially preferred for providing a gold / blue color change.

• - ein Silber/ Dielektrikum/ Aluminium-Schichtsystem, wobei die Schichtdicken der Silber-Schicht und der Aluminium-Schicht identisch oder verschieden sind;
• - ein Silber/Dielektrikum/Silber-Schichtsystem, wobei die Schichtdicken der beiden Silber-Schichten verschieden sind;
• - ein Aluminium/Dielektrikum/ Aluminium-Schichtsystem, wobei die Schichtdicken der beiden Aluminium-Schichten verschieden sind.

The above-mentioned multilayer structures having two semi-transparent metallic layers and a dielectric layer disposed between the two semitransparent metallic layers may have a symmetrical three-layer structure in which both the material and the layer thickness of the two semitransparent metallic layers are identical. Alternatively, however, there may also be an asymmetrical three-layer structure in which the material and / or the layer thickness of the two semitransparent metallic layers are different, eg

• a silver / dielectric / aluminum layer system, wherein the layer thicknesses of the silver layer and the aluminum layer are identical or different;
• - A silver / dielectric / silver layer system, wherein the layer thicknesses of the two silver layers are different;
• - An aluminum / dielectric / aluminum layer system, wherein the layer thicknesses of the two aluminum layers are different.

• - im Auflicht Magenta, im Durchlicht Blau-Grün;
• - im Auflicht Türkis, im Durchlicht Orange-Gelb;
• - im Auflicht Gold, im Durchlicht Blau-Violett;
• - im Auflicht Silber, im Durchlicht Violett.

The abovementioned multi-layered layer structures not only make it possible to produce a semitransparent functional layer that appears gold-colored when viewed in reflected light and shows a blue hue when viewed in transmitted light, but further color changes can be produced depending on the choice of the layer thickness, in particular of the dielectric layer, eg

• Magenta in transmitted light, blue-green in transmitted light;
• - in incident light turquoise, in transmitted light orange-yellow;
• - in reflected light gold, in transmitted light blue-violet;
• - in reflected light silver, in transmitted light violet.

A semitransparent functional layer which has different shades when viewed in reflected light on the one hand and when viewed in transmitted light on the other hand, can also be based on an effect pigment composition. Printed layers based on an effect pigment composition which, when viewed in incident light, show a different color than when viewed in transmitted light, in particular a gold / blue color change, a gold / violet color change, a green / gold / magenta color change, a Violet / green color change or a silver / opaque color change, are eg in the WO 2011/064162 A2 described. The pigments preferably have a longest dimension of edge length from end-to-end in a range of 15 nm to 1000 nm and are based on a transition metal selected from the group consisting of Cu, Ag, Au, Zn, Cd, Ti, Cr, Mn, Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt. The transition metal is preferably Ag. The aspect ratio (ie the ratio of the longest dimension from end to end relative to the thickness) is preferably at least 1.5, in particular in a range from 1.5 to 300. The ratio of the binder to metal pigment is preferably below 10: 1, in particular below 5: 1. Depending on the choice of aspect ratio of the pigment, its longest end-to-end dimension, and adjustment of the pigment / binder ratio, the color can be seen in transmission and the color when viewed in reflection (eg, blue in Transmission and silver, gold, bronze, copper or violet in reflection, in addition also violet, magenta, pink, green or brown in transmission and different colors in reflection, which depend on the choice of pigment / binder ratio). Colors with gold / blue color change between reflection and transmission (in other words, between incident light and transmitted light observation) are, for example, in Examples 1, 2 and 3 in Table 1 of FIG WO 2011/064162 A2 called. Further, Example 4 shows a color with gold / violet color change, Example 5 a color with green-gold / magenta color change, Example 7 a color with violet / green color change and Example 8 a color with silver / opaque color change.

• - Klebschicht, die z.B. für das Aufbringen des Sicherheitselements auf ein Wertdokumentsubstrat, wie etwa ein Banknotensubstrat, geeignet ist;
• - Schicht mit einer reflektierenden Mikrostruktur;
• - optional eine opake Schicht mit Aussparungen in Form von Mustern, Zeichen oder einer Codierung;
• - semitransparente Funktionsschicht;
• - Trägerfolie.

The security element according to the invention expediently has the following structure, wherein additional layers and films are conceivable:

• Adhesive layer suitable, for example, for applying the security element to a value document substrate, such as a banknote substrate;
• Layer with a reflective microstructure;
• Optionally, an opaque layer with recesses in the form of patterns, characters or an encoding;
• - semitransparent functional layer;
• - Carrier film.

• - Klebschicht, die z.B. für das Aufbringen der Folie auf ein Wertdokumentsubstrat, wie etwa ein Banknotensubstrat, geeignet ist;
• - Schicht mit einer reflektierenden Mikrostruktur;
• - Trägerfolie;
• - semitransparente Funktionsschicht;
• - optional ein Schutzlack oder eine Schutzfolie, um die semitransparente Funktionsschicht vor schädlichen Umwelteinflüssen zu schützen;

wobei entweder zwischen der Schicht mit der reflektierenden Mikrostruktur und der Trägerfolie oder zwischen der Trägerfolie und der semitransparenten Funktionsschicht optional eine opake Schicht mit Aussparungen in Form von Mustern, Zeichen oder einer Codierung angeordnet ist.According to a variant, the security element according to the invention may have the following structure, wherein additional layers and films are conceivable:

• Adhesive layer suitable, for example, for applying the film to a value document substrate, such as a banknote substrate;
• Layer with a reflective microstructure;
• - Carrier film;
• - semitransparent functional layer;
• - Optionally, a protective lacquer or a protective film to protect the semi-transparent functional layer from harmful environmental influences;

either between the layer with the reflective microstructure and the carrier foil or between the carrier film and the semi-transparent functional layer optionally an opaque layer with recesses in the form of patterns, characters or a coding is arranged.

The opaque layer may in particular be a metallization obtainable, for example, by vapor deposition or a color layer obtainable, for example, by means of a printing process. The production of structured metallizations by means of a washing process is known in the art, see for example the document EP 1972462 B1 and the prior art cited therein. To produce the color layer, platelet-shaped metal pigments may furthermore be used, for example from the publications 2013/186167 A2, US Pat. WO 2010/069823 A1 . WO 2005/051675 A2 (See eg the description on page 11 , Row 10 , until page 12 , penultimate paragraph) and WO 2011/064162 A2 are known. The platelet-shaped metal pigments described therein have the advantage that they conform to a substrate having a relief structure, in particular a relief with microstructures and / or nanostructures, so well that the difference to a conventional metallization obtainable by vapor deposition is almost no longer recognizable. The simple, printing-technical production of the reflection layer makes it possible to dispense with complex process steps, such as printing the carrier with a soluble wash in the form of a desired recess within the reflection layer to be produced, generating a metallization by vapor deposition and washing the washing paint together with the above the washing paint applied metallization.

Between the carrier film and the semitransparent functional layer it is expediently possible to arrange an embossing lacquer layer with an embossed relief, wherein the embossed relief is in particular a relief having micro and / or nanostructures. The semitransparent functional layer adapts to the relief so that the observer can perceive additional optically variable information, for example in the form of patterns, characters or an encoding, when viewing the security element in incident light. As already mentioned above, are optically variable security elements with a microstructure, which are suitable for hedging banknotes, eg from the WO 2007/079851 A1 and from the WO 2011/066991 A2 known.

Furthermore, the security element according to the invention may comprise the markings in the form of a coding, e.g. in the form of a one-dimensional bar code or a two-dimensional code or QR code. Such a code can be easily scanned with the smartphone.

The security element according to the invention can be present in particular as a patch or label, as a strip or as a thread. In particular, the security element may be in the form of a transfer element formed on a temporary support.

Further embodiments and advantages of the invention are explained below with reference to the schematically greatly simplified figures, in the representation of a scale and proportionate reproduction has been omitted in order to increase the clarity.

• 1 ein erfindungsgemäßes Sicherheitselement gemäß einem ersten Ausführungsbeispiel in Querschnittansicht;
• 2 ein erfindungsgemäßes Sicherheitselement gemäß einem zweiten Ausführungsbeispiel in Querschnittansicht;
• 3 ein erfindungsgemäßes Sicherheitselement gemäß einem dritten Ausführungsbeispiel in Draufsicht bei der Betrachtung im Tageslicht;
• 4 das erfindungsgemäße Sicherheitselement gemäß dem dritten Ausführungsbeispiel in Draufsicht bei der Betrachtung mit der Taschenlampe eines Smartphones in einem abgedunkelten Raum;
• 5 und 6 Darstellungen zur Erklärung der Funktionsweise des Erfindungsgegenstandes;
• 7 ein erfindungsgemäßes Sicherheitselement gemäß einem vierten Ausführungsbeispiel in Querschnittansicht;
• 8 das erfindungsgemäße Sicherheitselement gemäß dem dritten Ausführungsbeispiel in Querschnittansicht;
• 9 ein Ausführungsbeispiel für eine retroreflektierende Struktur in Draufsicht;
• 10 ein weiteres Ausführungsbeispiel für eine retroreflektierende Struktur in Draufsicht; und
• 11 ein Ausführungsbeispiel eines erfindungsgemäßen Sicherheitselements, das für das Absichern eines Kraftfahrzeug-Kennzeichens geeignet ist.

Show it:

• 1 a security element according to the invention according to a first embodiment in cross-sectional view;
• 2 a security element according to the invention according to a second embodiment in cross-sectional view;
• 3 a security element according to the invention according to a third embodiment in plan view when viewed in daylight;
• 4 the security element according to the invention according to the third embodiment in plan view when viewed with the flashlight of a smartphone in a darkened room;
• 5 and 6 Representations to explain the operation of the subject invention;
• 7 a security element according to the invention according to a fourth embodiment in cross-sectional view;
• 8th the security element according to the invention according to the third embodiment in cross-sectional view;
• 9 an embodiment of a retroreflective structure in plan view;
• 10 a further embodiment of a retroreflective structure in plan view; and
• 11 An embodiment of a security element according to the invention, which is suitable for securing a motor vehicle license plate.

The 1 shows a security element according to the invention 1 according to a first embodiment in cross-sectional view. The reflective microstructure is formed in the example by a retroreflective structure. The security element 1 based on a carrier foil 2 , For example, a polyethylene terephthalate (PET) film on the side facing the viewer with a semi-transparent functional layer 3 is provided. The semitransparent functional layer 3 obtainable by vapor deposition and has a multilayer structure with two semi-transparent Al-layers and one semi-transparent between the two Al layers arranged SiO ₂ layer. The semitransparent functional layer 3 appears golden when viewed in reflected light and shows a blue hue when viewed in transmitted light. The carrier foil 2 is on the semitransparent functional layer 3 opposite side with an embossing lacquer layer 4 Mistake. The embossing lacquer layer 4 is based, for example, on a UV varnish in which the relief of the retroreflective structure is embossed. The relief of the embossing lacquer layer 4 is with a reflective metal coating 5 , in the example an aluminum metallization, provided in order in this way together with the relief of the embossing lacquer layer 4 to form the retroreflective structure. Adjacent to the reflective metal coating 5 is an adhesive layer 6 arranged, for example, for the application of the security element 1 on a value document substrate, such as a banknote, is suitable.

The 2 shows a security element according to the invention 7 according to a second embodiment in cross-sectional view. The reflective microstructure is formed in the example by a retroreflective structure. The security element 7 based on a carrier foil 8th , For example, a polyethylene terephthalate (PET) film, which in the present example, an outer layer of the security element 7 forms. The carrier foil 8th is on its inside with a semitransparent functional layer 9 Mistake. The semitransparent functional layer 9 obtainable by vapor deposition and has a multilayer structure with two semi-transparent Al-layers and one semi-transparent between the two Al layers arranged SiO ₂ layer. The semitransparent functional layer 9 appears golden when viewed in reflected light and shows a blue hue when viewed in transmitted light. The semitransparent functional layer 9 is on the carrier film 8th opposite side with an embossing lacquer layer 10 Mistake. The embossing lacquer layer 10 based on a UV varnish in which the relief of the retroreflective structure is embossed. The relief of the embossing lacquer layer 10 is with a reflective metal coating 11 , in the example an aluminum metallization, provided in order in this way together with the relief of the embossing lacquer layer 10 to form the retroreflective structure. Adjacent to the reflective metal coating 11 is an adhesive layer 12 arranged, for example, for the application of the retroreflective sheeting 7 on a value document substrate, such as a banknote, is suitable.

The 3 shows a security element according to the invention 13 according to a third embodiment in plan view when viewed in daylight. The security element 13 appears to the viewer in the form of a gold-colored, metallic surface.

The 4 shows the security element according to the invention 13 according to the third embodiment in plan view in the illumination with a point light source, in particular when viewed with the flashlight of a smartphone in a darkened room. The viewer perceives the repeating characters "PL" and the line-shaped, square border in a bright blue color against a dark, black background.

The 8th shows the security element according to the invention 13 according to the third embodiment in cross-sectional view. The security element 13 based on a carrier foil 14 , For example, a polyethylene terephthalate (PET) film, which in the present example, an outer layer of the security element 13 forms. The carrier foil 14 is on its inside with a semitransparent functional layer 15 Mistake. The semitransparent functional layer 15 obtainable by vapor deposition and has a multilayer structure with two semi-transparent Al-layers and one semi-transparent between the two Al layers arranged SiO ₂ layer. The semitransparent functional layer 15 appears golden when viewed in reflected light and shows a blue hue when viewed in transmitted light. The semitransparent functional layer 15 is on the carrier film 14 opposite side with an optional, the semitransparent functional layer 15 protective transparent interlayer 16 , in the example an intermediate coating, provided. The optional intermediate layer 16 has opaque areas 17 on, for example, by printing with a black ink available. Alternatively, the opaque areas 17 be provided by a structured metallization. A structured metallization can be obtained, for example, by full-surface metallization and subsequent demetallization by means of a washing process or by full-surface metallization and subsequent demetallization by means of a laser. The opaque areas 17 put in the 4 illustrated dark background surrounding the characters "PL" and the square line border. Furthermore, the security element 13 an embossing lacquer layer 18 on. The embossing lacquer layer 18 is based on a UV varnish in which the relief of the reflective microstructure, in the example a retroreflective structure, is embossed. The relief of the embossing lacquer layer 18 is with a reflective metal coating 19 , in the example an aluminum metallization, provided in order in this way together with the relief of the embossing lacquer layer 18 to form the retroreflective structure. Adjacent to the reflective metal coating 19 is an adhesive layer 20 arranged, for example, for the application of the security element 13 on a value document substrate, such as a banknote, is suitable.

5 and 6 show representations to explain the operation of the subject invention.

The 5 shows a semitransparent functional layer 21 , which is obtainable by vapor deposition and has a multilayer structure with two semi-transparent Al layers and an SiO ₂ layer arranged between the two semitransparent Al layers (so-called Fabry-Perot thin-film structure). The semitransparent functional layer 21 appears golden when viewed in reflected light and shows a blue hue when viewed in transmitted light. The reference number 22 refers to the incoming white light. As a result of the semitransparent gold-blue color filter, the blue part of the color spectrum is transmitted (see the arrow with the reference number 24 which denotes the transmitted blue light). The complementary, so to speak gold-colored part is reflected (see the arrow with the reference number 23 which denotes the reflected, so-called golden, light).

The 6 shows the combination of the 5 known, semitransparent functional layer 21 together with retroreflectors 25 , in the example from the 1 . 2 and 8th known microprisms, which are provided with a reflective metal coating. In the combination of color filter 21 together with the retroreflectors 25 becomes the blue, transmitted color component 24 of the light spectrum through the retroreflectors 25 reflected and a second time through the gold-blue color filter 21 transmitted (see the dashed arrows with the reference numbers 26 and 27 each denoting the blue light). the blue light 27 is perceptible to the viewer, in the case of the embodiment according to the 4 in the form of the luminous, blue letters "PL" and the linear, square border.

That in the 1 . 2 and 8th If appropriate, the security element shown can be supplemented by at least one further layer, which has, for example, embossed structures such as, for example, micromirror arrangements or scattering structures or diffractive structures. As a result, it is possible, for example, to implement security elements based on the micromirror technology known in the prior art, which does not impair the color retroreflection at night. In the event of a vertical incidence of light at night, scattering structures can cause the gold-colored light component to be scattered.

The 7 shows a security element according to the invention 28 according to a fourth embodiment in cross-sectional view. The security element 28 based on a carrier foil 29 , For example, a polyethylene terephthalate (PET) film on the side facing the viewer with a semi-transparent functional layer 31 is provided. The semitransparent functional layer 31 obtainable by vapor deposition and has a multilayer structure with two semi-transparent Al-layers and one semi-transparent between the two Al layers arranged SiO ₂ layer. The semitransparent functional layer 31 appears golden when viewed in reflected light and shows a blue hue when viewed in transmitted light. The semitransparent functional layer 31 is by means of an embossing lacquer layer 30 on the carrier foil 29 applied. The embossing lacquer layer 30 Based on a UV varnish and has an embossed, containing microstructures relief. The semitransparent functional layer adapts to the relief, so that when the security element is viewed in reflected light, the observer can perceive additional, optically variable information dependent on the viewing angle in the form of patterns, characters or an encoding. The semitransparent functional layer 31 is with an optional, transparent protective layer 32 , eg a protective lacquer. The carrier foil 29 points to the semitransparent functional layer 31 opposite side an embossing lacquer layer 33 on. The embossing lacquer layer 33 is based on a UV varnish in which the relief of the reflective microstructure, in the example a retroreflective structure, is embossed. The relief of the embossing lacquer layer 33 is with a reflective metal coating 34 , in the example an aluminum metallization, provided in order in this way together with the relief of the embossing lacquer layer 33 to form the retroreflective structure. Adjacent to the reflective metal coating 34 is an adhesive layer 35 arranged, for example, for the application of the retroreflective sheeting 28 on a value document substrate, such as a banknote, is suitable.

The 9 shows an embodiment of a retroreflective structure in plan view. The retroreflectors are based on cube-corner structures or microprism structures in which the incident light is deflected successively at three mutually inclined boundary surfaces by approximately 45 ° and reflected back to the beam source. The 9 shows the geometry of embossed retroreflectors with triangular faces. The surface of the relief structure may be mirrored with a reflective metal layer.

The 10 shows a further embodiment of a retroreflective structure in plan view. Here is a geometry of embossed retroreflectors with square surfaces.

In the 1 . 2 . 6 . 7 and 8th Embodiments are shown in which the reflective microstructure is formed in the form of a retroreflective structure. Alternatively, the mosaic reflective microstructure could be formed from a plurality of reflective mosaic elements that are such that the markings in the form of patterns, characters, or coding upon tilting the security element have a dynamic motion effect by having different sets of mosaic elements with different characteristic parameters reflect incident light into different spatial areas. For example, that could be in the 1 relief shown 5 that in the 2 relief shown 11 that in the 6 relief shown 25 that in the 7 relief shown 34 or that in the 8th relief shown 19 respectively the appearance of the in the 7 Reliefs shown 31 exhibit, ie with the relief 31 identical, different or at least partially identical.

The 11 shows an embodiment of a security element according to the invention, which is suitable for securing a provided with a retroreflective structure motor vehicle license plate. The security element 21 based on a carrier foil 22 , For example, a polyethylene terephthalate (PET) film, which in the present example, an outer layer of the security element 21 forms. The carrier foil 22 is on its inside with a semitransparent functional layer 23 Mistake. The semitransparent functional layer 23 obtainable by vapor deposition and has a multilayer structure with two semi-transparent Al-layers and one semi-transparent between the two Al layers arranged SiO ₂ layer. The semitransparent functional layer 23 appears golden when viewed in reflected light and shows a blue hue when viewed in transmitted light. The semitransparent functional layer 23 is on the carrier film 22 opposite side with an optional, the semitransparent functional layer 23 protective transparent interlayer 24 , in the example an intermediate coating, provided. With the reference number 25 are opaque areas designated, for example, by printing with a black ink available. Alternatively, the opaque areas 25 be provided by a structured metallization. A structured metallization can be obtained, for example, by full-surface metallization and subsequent demetallization by means of a washing process or by full-surface metallization and subsequent demetallization by means of a laser. The opaque areas 25 represent, for example, characters, patterns or an encoding. Furthermore, the security element points 21 an adhesive layer 26 on.

With the reference number 27 is one with the security element 21 marked license plate or license plate of a motor vehicle. The license plate 27 points to the security element 21 opposite side a retroreflective structure 28 on.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2015/078572 A1 [0003, 0010]
• WO 2016/180522 A1 [0003, 0010]
• WO 2011/066990 A2 [0003, 0010]
• DE 102011101635 A1 [0005]
• US 4763985A [0011]
• US 20090300953 A1 [0011]
• WO 2014/117086 A1 [0011]
• US 6413615 B2 [0011]
• US 4478769A [0011]
• WO 2011/082761 A1 [0014]
• WO 2011/064162 A2 [0018, 0021]
• EP 1972462 B1 [0021]
• WO 2010/069823 A1 [0021]
• WO 2005/051675 A2 [0021]
• WO 2007/079851 A1 [0022]
• WO 2011/066991 A2 [0022]

Claims (29)

A security element for securing a value document, security document or a valuable article, with predetermined areas that the viewer in diffuse lighting, especially when viewed in daylight, appear in a first visually recognizable color and the illumination with a point light source, especially when viewed with the flashlight of a smartphone in a darkened room, appear in a second visually recognizable color and form markings in the form of patterns, characters or a coding, which are not visible to the viewer in diffuse lighting, especially when viewed in daylight, and only at the illumination with a punctiform light source, in particular when viewed with the flashlight of a smartphone in a darkened room, are recognizable, wherein the security element is a layer with a reflective microstructure and the viewer facing semitrans includes sparse functional layer and the semi-transparent functional layer is such that it has the first visually recognizable color when viewed in reflected light and has the second visually recognizable color when viewed in transmitted light. Security element after Claim 1 wherein the reflective microstructure is in the form of a retroreflective structure with triangular or quadrangular cube corners, or in the form of a micro-glass bead-based retroreflective structure, wherein the reflective microstructure is preferably provided with a metallization, more preferably with a specular metal coating. Security element after Claim 1 , wherein the reflective microstructure in the form of a mosaic consists of a plurality of reflective mosaic elements, which are characterized by the parameters size, outline shape, relief shape, reflectivity and spatial orientation and are such that the markings in the form of patterns, characters or a coding in the Tilting the security element have a dynamic movement effect by different groups of mosaic elements with different characteristic parameters reflect incident light in different areas of space. Security element according to one of Claims 1 to 3 wherein the layer is provided with a reflective microstructure in the form of a metallized embossing lacquer layer. Security element according to one of Claims 1 to 4 in which the markings are formed in the form of patterns, characters or a coding by recesses in an opaque layer which is arranged between the semitransparent functional layer and the layer with the retroreflective structures, the opaque layer being in particular a metallization or a color layer. Security element after Claim 5 with reference to Claim 3 wherein the recesses in the opaque layer form first markings in the form of patterns, characters or an encoding, and the reflective microstructure in the form of a mosaic of a multiplicity of reflective mosaic elements form second markings in the form of patterns, characters or an encoding, the second marks preferably at least partially adapted to the first markings. Security element according to one of Claims 1 to 6 in which the semitransparent functional layer has a multilayer structure with two semitransparent metallic layers and a dielectric layer arranged between the two semitransparent metallic layers. Security element after Claim 7 wherein the two semitransparent metallic layers are independently formed of a metal and the metal is selected from the group consisting of Al, Ag, Ni, Cr, Cu, Au, Si and an alloy of one or more of the aforementioned elements; dielectric layer is an SiO ₂ layer, a ZnO layer, a ZnS layer, an Al ₂ O ₃ layer, a TiO ₂ layer, a layer of a nitride or oxynitride of any of Si, Zn, Al or Ti or a MgF ₂ layer or, for example, technically available, nitrocellulose layer. Security element after Claim 7 or 8th wherein the two semitransparent metallic layers are independently selected from Al or Ag and the dielectric layer is an SiO ₂ layer. Security element according to one of Claims 1 to 6 , wherein the semitransparent functional layer is obtainable by printing technology by means of an effect pigment composition. Security element according to one of Claims 1 to 6 , wherein the semitransparent functional layer has a multilayer structure based on interference layers consisting only of transparent layers, wherein the multilayer structure is based in particular on, preferably alternating, layers of TiO ₂ , Al ₂ O ₃ or other dielectrics. Security element according to one of Claims 1 to 6 , wherein the semitransparent functional layer based on a plasmonic color filter and in particular based on two-dimensional periodic nanostructures. Security element according to one of Claims 1 to 12 In the case of diffuse illumination, in particular when viewed in daylight, the predetermined areas appear golden to the observer and appear bluish when illuminated with a punctiform light source, in particular when viewed with the flashlight of a smartphone in a darkened room. Security element according to one of Claims 1 to 13 wherein the security element has the following structure: - adhesive layer; Layer with a reflective microstructure; Optionally, an opaque layer with recesses in the form of patterns, characters or an encoding; - semitransparent functional layer; - Carrier film. Security element according to one of Claims 1 to 13 wherein the security element has the following structure: - adhesive layer; Layer with a reflective microstructure; - Carrier film; - semitransparent functional layer; wherein either an opaque layer with recesses in the form of patterns, characters or a coding is optionally arranged either between the layer having the reflective microstructure and the carrier film or between the carrier film and the semitransparent functional layer. Security element after Claim 14 or 15 in which an embossing lacquer layer with an embossed relief is arranged between the carrier foil and the semitransparent functional layer, wherein the embossed relief is in particular a relief having micro and / or nanostructures. Data carrier, in particular a value document, security document or a valuable article, comprising the security element according to one of Claims 1 to 16 , A security element for securing a data carrier provided with a retroreflective structure, wherein the security element has predetermined areas which appear to the viewer in diffuse illumination, especially when viewed in daylight, in a first visually recognizable color and in the illumination with a punctiform light source, in particular the viewing with the flashlight of a smartphone in a darkened room, appear in a second visually recognizable color and markings in the form of patterns, characters or a coding form, which are not recognizable to the viewer in diffused lighting, especially when viewed in daylight and only in the illumination with a point light source, especially when viewed with the flashlight of a smartphone in a darkened room, can be seen, the security element abzusi for bonding the security element with the and the semitransparent functional layer is such that it has the first visually recognizable color when viewed in reflected light and when viewed in transmitted light, the second visually recognizable color having. Security element after Claim 18 in which the markings are formed in the form of patterns, characters or a coding by recesses in an opaque layer which is arranged between the semitransparent functional layer and the adhesive layer. Security element according to one of Claims 18 or 19 in which the semitransparent functional layer has a multilayer structure with two semitransparent metallic layers and a dielectric layer arranged between the two semitransparent metallic layers. Security element after Claim 20 wherein the two semitransparent metallic layers are independently formed of a metal and the metal is selected from the group consisting of Al, Ag, Ni, Cr, Cu, Au, Si and an alloy of one or more of the aforementioned elements; dielectric layer is an SiO ₂ layer, a ZnO layer, a ZnS layer, an Al ₂ O ₃ layer, a TiO ₂ layer, a layer of a nitride or oxynitride of any of Si, Zn, Al or Ti or a MgF ₂ layer or, for example, technically available, nitrocellulose layer. Security element after Claim 20 or 21 wherein the two semitransparent metallic layers are independently selected from Al or Ag and the dielectric layer is an SiO ₂ layer. Security element according to one of Claims 1 to 6 , wherein the semitransparent functional layer is obtainable by printing technology by means of an effect pigment composition. Security element according to one of Claims 18 or 19 , wherein the semitransparent functional layer has a multilayer structure based on interference layers consisting only of transparent layers, wherein the multilayer structure is based in particular on, preferably alternating, layers of TiO ₂ , Al ₂ O ₃ or other dielectrics. Security element according to one of Claims 18 or 19 wherein the semitransparent functional layer is based on a plasmonic color filter and in particular based on two-dimensional periodic nanostructures. Security element according to one of Claims 18 to 25 In the case of diffuse illumination, in particular when viewed in daylight, the predetermined areas appear golden to the observer and appear bluish when illuminated with a punctiform light source, in particular when viewed with the flashlight of a smartphone in a darkened room. Security element according to one of Claims 18 to 26 wherein the security element has the following structure: - adhesive layer; Optionally, an opaque layer with recesses in the form of patterns, characters or an encoding; - semitransparent functional layer; - Carrier film. With a retroreflective structure provided data carrier, in particular a license plate or a number plate, a traffic sign or a traffic sign, a billboard or advertising space, or security clothing, comprising the security element according to one of Claims 18 to 27 , Use of the security element according to one of Claims 18 to 27 for securing a data carrier provided with a retroreflective structure, in particular a license plate, a road sign, a billboard or advertising space, or safety clothing.

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