EP3305543B1 - Security element and valuable document with this security element - Google Patents

Description

The invention relates to a security element in the form of a strip having a first and second polymeric layer, with a luminescent under UV radiation halftone image between the first and second layer, wherein the halftone image has an opacity and at least one imprinting surface forms with a boundary contour within the security element.

From the prior art ( EP 1 241 022 A1 ) security elements in the form of a strip are known which have a luminescent under UV radiation printing between a first polymeric layer and a second polymeric layer. However, such a luminescent printing always shows a certain opacity, so that the boundary contour of the imprint area on the security element is comparatively strongly recognizable. Disadvantageously, such imprints can lead to differences in opacity on the security element and thus impair counterfeiting security, etc.

The invention has therefore set itself the task, starting from the above-described prior art, to increase the security against counterfeiting of a security element with a luminescent imprint.

The invention achieves this object by virtue of the fact that at least one of the two polymer layers has opacity at least in the region of the boundary contour of the imprint area and is adjusted in its opacity to the opacity of the imprint area in order to visually recognize the boundary contour of the imprint area attenuate the luminescent halftone printed image on the security element.

If at least one of the two polymer layers has an opacity in the region of the boundary contour of the imprint area, in particular over the entire area, and is adapted in its opacity to the opacity of the imprint area, in order to reduce the visual perceptibility of the boundary contour of the imprint area of the luminescent halftone image on the security element to a great extent counterfeit-proof security feature on the security element to be created - not least because of the increased manufacturing effort. Furthermore, it is thus possible to provide a security element with a hidden security feature, which security feature does not change the general appearance of the security element under certain conditions. In accordance with the invention, the boundary contour of this luminescent imprint can be attenuated or concealed relative to the security element such that the visual recognizability of the imprint, especially under white light, is not or hardly possible - but visually easily recognizable, for example, under UV light irradiation. In contrast to the prior art, in which due to not given adjustment of opacity a visually easily recognizable imprint can already provide an indication with respect to a security feature, causing a security feature - which is under certain conditions, especially in white light, not recognizable or difficult recognizable - less attention to the security element according to the invention, which in turn can significantly contribute to the improvement of a proof of authenticity and subsequently the security against counterfeiting.

In general, it is mentioned that the term halftone print image can be understood to mean a printed image with a print pattern in which the halftone dots or printing dots can be applied next to and above one another. By additive color mixing and / or intensity variation, an image effect can be generated. Raster print images can represent single or multi-color images.

In general, it is further mentioned that for this luminescent under UV radiation printing, for example, a printing ink can be used which contains luminescent dyes or pigments. Such luminescent dye and / or luminescent pigment can, for example under the action of radiation, be brought into an energetically excited state and then spontaneously pass into a state of lower energy - whereby photons of a certain wavelength are emitted, which is perceptible by the human eye at the appropriate wavelength ,

In general, it is further noted that the luminescent imprint and / or the halftone image can be printed by any conventional, for example, contact or non-contact printing method, such as gravure, screen, pad, offset, lithographic, flexographic, high-pressure or inkjet. Printing method, etc. can be applied.

In general, it is also mentioned that the opacity of the polymeric layers is understood as the opacity in the wavelength range of visible light.

If the opacity values of the halftone printed image and of at least one of the polymeric layers are substantially the same, a stable and particularly simple and cost-effective visual masking of the boundary contour of the luminescent imprint can be achieved. If the opacity values of the halftone printed image and of the second polymeric layers are substantially the same, or in particular adapted to one another, it can be ensured in a simple manner that the advantages according to the invention are likewise easily achieved in those areas in which no halftone printed image is arranged above the second layer.

The visual recognizability of the boundary contour of the imprint area of the luminescent halftone printed image on the security element can be attenuated particularly reliably when a diffusely diffusing layer of paint forms the first layer. In this regard, in particular a matt lacquer layer can be distinguished. Such a diffusely scattering lacquer layer can namely steadily compensate for different opacities on the security element and thus ensure a desired, above all homogeneous, appearance of the security element. A particularly tamper-proof security element is to be provided in this way.

In general, it is also mentioned that the security element can be embedded particularly advantageously in a value document if the first layer can be printed. Alternatively, it is also possible to optically and / or haptically adapt the first layer and the value document to one another. By a full-surface printability, the security against counterfeiting of the security element can be improved.

If the second layer is formed as an adhesive layer, then the security element can be protected from external influences and at the same time be provided on a valuable document or on any carrier in a manner that are easy to handle. In particular, this can prevent oxidation of the fluorescent dyes of the luminescent printing. According to the invention, such a particularly robust and stable security element can be created.
The adhesive layer may in particular comprise a heat-sealable or a cold seal adhesive. Alternatively, however, the second layer can also have a self-adhesive coating, a radiation-curing coating or other comparable coatings.

In general, it is mentioned that the second layer can also be translucent. In this case, a particularly easy to handle and also stable security element can be created, since the second layer does not affect the visual appearance of the security element and thus its security features.

If the raster print image has luminescent screen dots in different colors, a multicolor luminescent print can be created in a structurally simple manner. This multi-color luminescent imprint can even be made real-colored if red and / or green and / or blue luminescent screen dots are used.

A particularly tamper-proof security feature on the luminescent imprint can be created if the raster print image has a honeycomb grid.

If the honeycomb grid has hexagonal grid cells which consist of juxtaposed triangular grid points, then the security against forgery of the security feature can be further improved - in particular if the grid points adjoin one another.

If each grid cell in each case has two grid points which have the same luminescent color, the luminescence intensity and the color reproduction of the luminescent print can be made particularly homogeneous.

If the color impression of the raster cell is formed as a function of missing raster points, the variation of the color rendition and the luminescence intensity within the raster print image can be achieved in a structurally simple manner.

In addition, the security element can be distinguished when the color impression of the screen cell is formed as a function of the size of the screen dots. As a result, among other things, a particularly homogeneous raster print image can be created - which in turn can be beneficial to the security against forgery of the security element.

The raster points of the raster printed image preferably have a size of 10 to 500 μm, in particular of 50 to 200 μm.

In general, it is mentioned that the security against forgery of the security element can be further improved if an embossed diffraction structure and a metallization adjoining this diffraction structure are provided between the first and second layer. The embossed diffraction structure can cooperate in particular with the subsequent metallization in order to form a reflection hologram.

In general, it will be appreciated that such a reflection hologram may be selectively mounted in the viewing direction above or below the luminescent imprint. If the reflection hologram is provided over the imprint, the visual recognizability of the imprint must be ensured by means of corresponding recesses in the reflection hologram.

In general, it is further stated that the security against forgery of the security element can be further increased if it has machine-readable security features, in particular with magnetic properties, for example in the form of a magnetic strip. It is also conceivable that such magnetic properties are provided in combination with a hologram.

In general, it is also stated that a particularly high stability and security against forgery of the security element can be achieved if the security element has a thickness of less than or equal to 30 μm, in particular less than or equal to 25 μm. As a result, a virtually collection-free embedding of the security element in a substrate or value document is possible.

The security element according to the invention can bring its advantages in particular if it is provided on a substrate of a document of value - thus connected to it. As a document of value, for example, a banknote, a tax stamp, passport, driver's license or identity card and so on imaginable.

Above all, value documents can be distinguished in this regard which have a security element according to the invention which extends continuously from one edge of the substrate to the opposite edge of the substrate. These may be strip, thread or tape-shaped security elements.

The security against forgery of the value document can be further improved if the surfaces of the first layer of the security element and of the value document are essentially identical in their haptic properties and / or in their visual appearance. Thus, for example, subsequently a visually recognizable difference in opacity between substrate and luminescent imprint can be avoided - which, when viewed under white light, can hide this steadily in the value document. With regard to such an opacity difference, a printable matte lacquer layer on the security element may be particularly distinguished.

Fig. 1

eine Schnittansicht durch ein Wertdokument mit einem Sicherheitselement gemäß einer ersten Ausführungsvariante,

Fig. 2

eine Schnittansicht durch ein Wertdokument mit einem Sicherheitselement gemäß einer zweiten Ausführungsvariante, und

Fig. 3

eine Draufsicht auf das Sicherheitselement aus Fig. 2.

In the figures, for example, the subject invention is illustrated in more detail with reference to a variant embodiment. Show it

Fig. 1

a sectional view through a value document with a security element according to a first embodiment variant,

Fig. 2

a sectional view through a value document with a security element according to a second embodiment, and

Fig. 3

a plan view of the security element Fig. 2 ,

According to Fig. 1 a security element 100 is shown, which has a first polymeric layer 1 and a second polymeric layer 2, which are applied to a carrier substrate 10, in particular a carrier film. Between the first and second polymeric layer 1, 2 is a luminescent under UV radiation, an opacity exhibiting raster print image 3 arranged on the carrier substrate 10, which forms at least one delimited by a boundary contour 4 printing surface 5 on the security element 100 as a security feature. The raster printed image 3 can in particular have a higher opacity compared to the unprinted area, or be opaque.

According to the invention, the first polymeric layer 1 and / or the second polymeric layer 2 are preferably adjusted in their opacity to the opacity of the imprint area 5 in areas of the boundary contour 4 of the imprint area 5, but in particular over their full area, in order to increase the visual perceptibility of the boundary contour 4 of the imprint area 5 weaken. In the illustrated embodiment, the luminescent halftone printed image 3 is therefore hidden in the security element 100 when viewed under white light. The conditions under which the halftone printing image 3 is hidden or visible may of course be varied as needed. As a result, in addition to the increase in the design effort - and thus a more difficult replica - at the same time forgery protection, etc. increased by the inventive security element 100.

It can be particularly distinguished when the first polymeric layer 1 is formed by a diffusely scattering matt lacquer layer 6. This ensures the advantages according to the invention with respect to the boundary contour 4 - but can also be distinguished by adapting the overall appearance of the security element 100 to that of the value document 200. Furthermore, the first layer 1, in particular in the form of the matt lacquer layer 6, can be printed easily and can thus be embedded in a value document in a particularly forgery-proof manner. The first layer 1 of the security element 100 is visually adapted to the surface texture of the value document 200, or to the substrate 21 of the document of value 200 - which may also be considered with regard to the haptic properties.

The second layer 2 is in the, in Fig. 1 illustrated example as a translucent heat sealing lacquer layer 8 is formed. In addition, a protective lacquer 7 is applied over the heat sealing lacquer 8 in order to protect the luminescent dyes contained in the halftone printed image 3 from oxidation. Alternatively, the opacity of the halftone printing image 3 and the second polymeric layer 2 may be substantially the same, whereby the visual recognizability of the boundary contour 4 can be particularly easily reduced.

The raster print image 3 of the security element 100 has, as in the top view in FIG Fig. 3 to recognize red, green and blue luminescent halftone dots 11, 12 and 13. In this case, the grid points 11, 12, 13 are arranged in a honeycomb grid 14 of the raster print image 3 in such a way that each of the hexagonal grid cells 15 of the honeycomb grid 14 has six grid points 11, 12, 13 arranged next to one another and adjoining one another having. Each raster cell 15 shows two red-luminescent halftone dots 11, two green-luminescent halftone dots 12 and two blue-luminescent halftone dots 13. The differently colored halftone dots 11, 12, 13 are arranged alternately in color, and have a size of 10 to 500 μm, in particular from 50 to 200 μm, up.

In order to vary the color impression of a raster cell 15 or to produce a true color image, individual raster points 16 are omitted in the raster cell 15 - as shown in detail in FIG Fig. 3 is shown. It is also conceivable, but not shown in detail in the figures, that the color impression of the raster cells 15 is formed over the varying size of the raster points 11, 12, 13.

In Fig. 2 a security element 101 is shown, wherein between the first layer 1 and the second layer 2 an embossing lacquer layer 17 is provided, which has an embossed diffraction structure 18. In addition, a partial metallization 19 is applied to the embossing lacquer layer 17 as a reflection layer, in order to cooperate with the embossed diffraction structure 18 to form a reflection hologram 20. The reflection hologram 20 may be partially provided on the security element 101 in the form of stripes, characters or patterns.

The security elements 100, 101 according to the invention have a thickness of less than or equal to 30 .mu.m, in particular less than or equal to 25 .mu.m.

In Fig. 1 and Fig. 2 Value documents 200, 201 are shown, wherein a security element 100 or 101 is respectively applied to the substrate 21 of the value document 200, 201. According to the invention, the value documents 200, 201 may be a banknote, a driver's license, an identity card, a passport or similar.

The security elements 100, 101 can thereby extend from one edge of the substrate to the opposite edge of the substrate 21, in particular in the form of a band or a strip, but this has not been shown in detail in the figures.

Claims (15)

1. A security element in the form of a strip having a first (1) and second polymer layer (2), and having a visually recognizable grid printed image (3), which luminesces under UV radiation, between the first (1) and second layer (2), wherein the grid printed image (3) has an opacity and forms at least one imprint area (5) having a boundary contour (4) within the security element (100, 101), wherein at least one of the two polymer layers (1, 2) has an opacity at least in the region of the boundary contour (4) of the imprint area (5) and is designed as adapted in its opacity to the opacity of the imprint area (5), to diminish the visual recognizability of the boundary contour (4) of the imprint area (5) of the luminescent grid printed image (3) on the security element (100, 101).
2. The security element according to claim 1, characterized in that at least one of the two polymer layers (1, 2) is designed as adapted to the opacity of the imprint area (5) over the entire area.
3. The security element according to any one of claims 1 or 2, characterized in that the opacity values of the grid printed image (3) and at least one of the polymer layers (1, 2) are essentially equal.
4. The security element according to any one of claims 1 to 3, characterized in that a diffusely scattering lacquer layer (6), more particularly a matte lacquer layer (6), forms the first layer (1).
5. The security element according to any one of claims 1 to 4, characterized in that the second layer (2) is formed as an adhesive layer (8).
6. The security element according to any one of claims 1 to 5, characterized in that the grid printed image (3) has grid points (11, 12, 13) which luminesce in different colors, more particularly red and/or green and/or blue.
7. The security element according to any one of claims 1 to 6, characterized in that the grid printed image (3) has a honeycomb grid (14).
8. The security element according to claim 7, characterized in that the honeycomb grid (14) has hexagonal grid cells (15), which consist of triangular grid points (11, 12, 13), which are arranged adjacent to one another, more particularly adjoining one another.
9. The security element according to claim 8, characterized in that each grid cell (15) has two grid points (11, 12, 13) which luminesce in the same color.
10. The security element according to claim 9, characterized in that the color impression of the grid printed image (3) is formed as a function of absent grid points (16).
11. The security element according to claim 9 or 10, characterized in that the color impression of the grid printed image (3) is formed as a function of the size of the grid points (11, 12, 13).
12. The security element according to any one of claims 6 to 11, characterized in that the grid points (11, 12, 13) of the grid printed image (3) have a size of 10 to 500 µm, more particularly 50 to 200 µm.
13. A value document having a substrate (21) and having a security element (100, 101) according to any one of claims 1 to 12, which is provided on the substrate (21).
14. The value document according to claim 13, characterized in that the security element (100, 101) extends continuously from one edge of the substrate (21) to the opposite edge of the substrate (21).
15. The value document according to claim 13 or 14, characterized in that surfaces of the first layer (1) of the security element (100, 101) and of the value document (200, 201) are essentially identical in the haptic properties and/or in the visual appearance thereof.

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