Security element and value document having this security element

Abstract

A security element and a value document having such a security element in the form of a strip having a first and second polymer layer are shown, having a visually recognizable halftone printed image, which is luminescent under UV radiation, between the first and second layer, wherein the halftone printed image has an opacity and forms at least one imprint area having a boundary contour within the security element. To increase the forgery protection, it is proposed that at least one of the two polymer layers have an opacity at least in the region of the boundary contour of the imprint area and be adapted in its opacity to the opacity of the imprint area, in order to diminish the visual recognizability of the boundary contour of the imprint area of the luminescent halftone printed image on the security element.

Claims

1. A security element in a form of a strip, comprising: a first polymer layer; a second polymer layer; and a visually recognizable halftone printed image, which luminesces under UV radiation, positioned between the first polymer layer and the second polymer layer, wherein the halftone printed image has a first opacity and forms at least one imprint area having the first opacity and a boundary contour within the security element, and wherein at least one of the first and second polymer layers has a second opacity at least in a region of the boundary contour of the imprint area that diminishes a visual recognizability of the boundary contour of the imprint area of the halftone printed image on the security element, and opacity values of the first opacity of the halftone printed image and the second opacity of at least one of the first and second polymer layers are essentially equal.

2. The security element according to claim 1, wherein the second opacity of at least one of the first and second polymer layers is present over an entire area of the imprint area having the first opacity.

3. The security element according to claim 1, wherein a diffusely scattering lacquer layer forms the first layer.

4. The security element according to claim 3, wherein the diffusely scattering lacquer layer is a matte lacquer layer.

5. The security element according to claim 1, wherein the second layer is formed as an adhesive layer.

6. The security element according to claim 1, wherein the halftone printed image has grid points which luminesce in different colors.

7. The security element according to claim 6, wherein the grid points of the halftone printed image have a size of 10 to 500 μm.

8. The security element according to claim 1, wherein the halftone printed image has a honeycomb grid.

9. The security element according to claim 8, wherein the honeycomb grid has hexagonal grid cells, which consist of triangular grid points, which are arranged adjacent to one another.

10. The security element according to claim 9, wherein each grid cell has two grid points which luminesce in a same color.

11. The security element according to claim 10, wherein a color impression of the halftone printed image is formed as a function of absent grid points.

12. The security element according to claim 10, wherein a color impression of the halftone printed image is formed as a function of a size of the grid points.

13. The security element according to claim 9, wherein the triangular grid points are arranged adjoining one another.

14. A value document having a substrate and having a security element according to claim 1, which is provided on the substrate.

15. The value document according to claim 14, wherein the security element extends continuously from one edge of the substrate to an opposite edge of the substrate.

16. The value document according to claim 14, wherein surfaces of the first layer of the security element and of the value document are essentially identical in haptic properties and/or in a visual appearance.

17. The security element according to claim 1, wherein opacity values of the first opacity of the halftone printed image and the second opacity of at least one of the first and second polymer layers are equal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The subject matter of the invention is illustrated in greater detail in the figures as an example on the basis of an embodiment variant. In the figures:

(2) FIG. 1 shows a sectional view through a value document having a security element according to a first embodiment variant,

(3) FIG. 2 shows a sectional view through a value document having a security element according to a second embodiment variant, and

(4) FIG. 3 shows a top view of the security element from FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(5) According to FIG. 1, a security element 100 is shown, which has a first polymer layer 1 and a second polymer layer 2, which are applied to a carrier substrate 10, in particular a carrier film. A halftone printed image 3, which has an opacity and is luminescent under UV radiation, is arranged between the first and second polymer layers 1, 2 on the carrier substrate 10, which forms at least one imprint area 5, which is delimited by a boundary contour 4, on the security element 100 as a security feature. The halftone printed image 3 is visually recognizable. The halftone printed image 3 can in this case in particular have a higher opacity in comparison to the unprinted region, or can be opaque.

(6) According to the invention, the first polymer layer 1 and/or the second polymer layer 2 is/are preferably adapted in the opacity thereof to the opacity of the imprint area 5 in this case in regions of the boundary contour 4 of the imprint area 5, but particularly over the entire area, to thus diminish the visual recognizability of the boundary contour 4 of the imprint area 5. In the illustrated exemplary embodiment, the luminescent halftone printed image 3 is therefore concealed in the security element 100 upon observation under white light. The conditions under which the halftone printed image 3 are concealed or visible can be varied as needed, of course. Thus, in addition to increasing the design expenditure—and therefore more difficult simulation—forgery protection etc. are also increased by the security element 100 according to the invention.

(7) It can be distinguished in particular if the first polymer layer 1 is formed by a diffusely scattering matte lacquer layer 6. This stably ensures the advantages according to the invention with regard to the boundary contour 4—but can also be distinguished in that it adapts 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 matte lacquer layer 6, is easily printable and can therefore be embedded in a particularly forgery-proof manner in a value document. The first layer 1 of the security element 100 is visually adapted in this case to the surface condition of the value document 200 or to the substrate 21 of the value document 200—which can also be planned with regard to the haptic properties.

(8) In the example shown in FIG. 1, the second layer 2 is designed as a translucent hot seal lacquer layer 8. In addition, a protective lacquer 7 is applied over the hot seal lacquer 8, to protect the luminescent colorants contained in the halftone printed image 3 from oxidation. The opacity of the halftone printed image 3 and the second polymer layer 2 can alternatively be essentially equal, whereby the visual recognizability of the boundary contour 4 can be reduced particularly simply.

(9) The halftone printed image 3 of the security element 100 has, as can be seen in the top view in FIG. 3, red, green, and blue luminescent grid points 11, 12, and 13. A true-color luminescent halftone printed image 3 thus results. The grid points 11, 12, 13 are arranged in this case in a honeycomb grid 14 of the halftone printed image 3 such that each of the hexagonal grid cells 15 of the honeycomb grid 14 has six grid points 11, 12, 13, which are arranged adjacent to one another and adjoining one another. Each grid cell 15 displays in this case two red luminescent grid points 11, two green luminescent grid points 12, and two blue luminescent grid points 13. The different-colored grid points 11, 12, 13 are each arranged in alternating colors, and have a size of 10 to 500 μm, in particular 50 to 200 μm in this case.

(10) To vary the color impression of a grid cell 15 and/or to create a true-color image, individual grid points 16 are omitted in the grid cell 15—as is shown in the detail portion in FIG. 3. It is also conceivable, but is not shown in greater detail in the figures, that the color impression of the grid cells 15 is formed via the varying size of the grid points 11, 12, 13.

(11) FIG. 2 shows a security element 101, wherein an embossing lacquer layer 17, which has an embossed diffraction structure 18, is provided between the first layer 1 and the second layer 2. In addition, a partial metallization 19 is applied as a reflection layer to the embossing lacquer layer 17, to interact with the embossed diffraction structure 18 to form a reflection hologram 20. The reflection hologram 20 can be partially provided in this case in the form of strips, characters, or patterns on the security element 101.

(12) The security elements 100, 101 have a thickness of less than or equal to 30 μm, in particular less than or equal to 25 μm.

(13) FIG. 1 and FIG. 2 show value documents 200, 201, wherein a security element 100 or 101 is applied in each case to the substrate 21 of the value document 200, 201, respectively. The value documents 200, 201 can be a banknote, a driver license, a personal identification, a passport, or a comparable item according to the invention.

(14) The security elements 100, 101 can extend in this case continuously from one edge of the substrate to the opposite edge of the substrate 21, in particular in the form of a tape or a strip, which was not shown in greater detail in the figures, however.