OA19555A

OA19555A - Security element and value document having said security element.

Info

Publication number: OA19555A
Application number: OA1201900122
Authority: OA
Inventors: Klaus Schmidegg; Sonja Landertshamer; Fabrice CAPIEZ; Olivier Martin; Roger Vilcot; Michel Blanc
Original assignee: Hueck Folien Gesellschaft M.B.H.; Banque De France
Priority date: 2016-10-04
Filing date: 2017-10-04
Publication date: 2020-12-11

Abstract

A security element ( 100, 101) and a value document (200, 201 ) having such a security element (100, 101) in the form of a strip having a first (1) and second polymer layer (2) are shown, having a visually recognizable grid printed image (3), which is luminescent 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). To increase the forgery protection, it is proposed that at least one of the two polymer layers (1,2) have an opacity at least in the region of the boundary contour (4) of the imprint area (5) and be adapted in its opacity to the opacity of the imprint area (5), in order 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).

Description

Security element and value document having this security element

The invention relates to a value document and a security element in the form of a strip having a first and se cond polymer layer, and having a visually recognizable grid printed image, which luminesces under UV radiation, between the first and second layer, wherein the grid printed image has an opacity and forms at least one imprint area having a boundary contour within the security element.

Security éléments in the form of a strip are known from the prior art (EP 1 241 022 Al), which hâve an imprint, which luminesces under UV radiation, between a first polymer layer and a second polymer layer, which imprint is visually recognizable. Such a luminescent imprint always displays a certain opacity, however, so that the boundary contour of the imprint area on the security element is comparatively strongly recognizable. Such imprints can disadvantageously resuit in opacity différences on the security element and therefore impair the forgery protection, etc.

The invention therefore has the object, proceeding from the prior art described at the outset, of increasing the forgery protection of a security element having a luminescent imprint.

The invention achieves the stated object in that at least one of the two polymer layers has an opacity at least in the région of the boundary contour of the imprint area and is designed as adapted in its opacity to the opacity of the imprint area, to diminish the visual recognizability of the boundary contour of the imprint area of the luminescent grid printed image on the security element.

If at least one of the two polymer layers has an opacity in the région of the boundary contour of the imprint area, in particular over the entire area, and is designed as adapted in its opacity to the opacity of the imprint area, to diminish the visual recognizability of the boundary contour of the imprint area of the luminescent grid printed image on the security element, a security feature which is forgery-proof to a high degree can be provided on the security element - not least as a resuit of the increased production expenditure. Furthermore, it is possible in this manner to provide a security element having a concealed security feature, which security feature does not change the general appearance of the security element under spécifie conditions. This is because, according to the invention, the boundary contour of this luminescent imprint can be diminished and/or concealed in relation to the security element such that the visual recognizability of the imprint, in particular under white light, is not possible or is hardly possible - but it is easily visually recognizable very well under irradiation using UV light, for example. In contrast to the prior art, in which a visually easily recognizable imprint can already provide an indication with regard to a security feature as a resuit of not providing adaptation of the opacity, a security feature - which is not recognizable or is recognizable with diffîculty under spécifie conditions, above ail in white light - causes less attention in the security element according to the invention, which can in turn substantially contribute to improving a proof of the authenticity and, as a further conséquence, the forgery protection.

In general, it is to be noted that a grid printed image can be understood as a printed image having a printed grid, in which the grid points or printed points can be plotted adjacent to one another and one above another. An image effect can be created by additive color mixing and/or intensity variation. Grid printed images can represent single-color or multicolor images.

In general, it is furthermore to be noted that for example, for this imprint which luminesces under UV radiation, a printing ink can be used which contains luminescent colorants or pigments. Such a luminescent colorant and/or luminescent pigment can be brought into an energetically excited State, for example, under the effect of radiation, and can then pass spontaneously into a State of lower energy, wherein photons of a spécifie wavelength are emitted, which is perceivable by the human eye in the case of a corresponding wavelength.

In general, it is furthermore to be noted that the luminescent imprint and/or the grid printed image can be applied using any common printing method, for example, a contact or contact-free printing method, for example, gravure printing, screen printing, pad printing, offset printing, lithographie printing, flexographic printing, relief printing, or inkjet printing methods, etc.

In general, it is moreover noted that the opacity of the polymer layers is understood as being opaque to light in the wavelength range of visible light.

If the opacity values of the grid printed image and at least one of the polymer layers are essentially equal, a stable and particularly simple and cost-effective visual concealment of the boundary contour of the luminescent imprint can be achieved. If the opacity values of the grid printed image and the second polymer layers are essentially equal, and/or are adapted to one another in particular, it can be ensured in a simple manner that the advantages according to the invention are also achieved in the régions in which no grid printed image is arranged above the second layer.

The visual recognizability of the boundary contour of the imprint area of the luminescent grid printed image on the security element can be diminished particularly reliably if a diffusely scattering lacquer layer forms the first layer. A matte lacquer layer can be distinguished in this regard in particular. This is because such a diffusely scattering lacquer layer can stably compensate for different opacities on the security element, and therefore ensure a desired above ail homogeneous - appearance of the safety element. A particularly forgery-proof security element is to be provided in this manner.

In general, it is additionally to be noted that the security element can particularly advantageously be embedded in a value document if the first layer is printable. Altematively, it is also possible to adapt the first layer and the value document optically and/or haptically to one another. The forgery protection of the security element can be improved by a full-area printability.

If the second layer is formed as an adhesive layer, the security element can thus be protected from external influences and at the same time it can be provided in a handling-friendly manner on a value document or on any arbitrary carrier. In particular, oxidation of the fluorescent colorant of the luminescent imprint can thus be avoided. According to the invention, a particularly robust and stable security element can be provided in this manner.

The adhesive layer can hâve in particular a hot-seal adhesive or a cold-seal adhesive. The second layer can altematively also hâve a self-adhesive coating, a radiation-curing coating, or other comparable coatings, however.

In general, it is to be noted that the second layer can additionally be translucent. In this case, a particularly handling-friendly and also stable security element can be provided, since the second layer does not impair the visual appearance of the security element and therefore the security features thereof.

If the grid printed image has grid points which luminesce in different colors, a multicolor luminescent imprint can be provided in a structurally simple manner. This multicolored luminescent imprint can even be designed as true color, if red and/or green and/or blue luminescent grid points are used.

A particularly forgery-proof security feature on the luminescent imprint can be provided if the grid printed image has a honeycomb grid.

If the honeycomb grid has hexagonal grid cells, which consist of triangular grid points arranged adjacent to one another, the forgery protection of the security feature can be further improved in particular if the grid points adjoin one another.

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

If the color impression of the grid cell is formed as a function of absent grid points, the variation of the color reproduction and the luminescent intensity within the grid printed image can be achieved in a structurally simple manner.

In addition, the security element can be distinguished if the color impression of the grid cell is formed as a function of the size of the grid points. A particularly homogeneous grid printed image can thus be provided, inter alia, which in tum can contribute to the forgery protection of the security element.

The grid points of the grid printed image preferably hâve a size of 10 to 500 pm, in particular of 50 to 200 pm.

In general, it is to be noted that the forgery protection of the security element is further improvable if an embossed diffraction structure and a metallization adjoining this diffraction structure are provided between first and second layers. The embossed diffraction structure can interact in particular with the adjoining metallization in this case, to form a reflection hologram.

In general, it is to be noted that such a reflection hologram can optionally be attached in the observation direction above or below the luminescent imprint. If the reflection hologram is provided above the imprint, the visual recognizability of the imprint thus has to be ensured by corresponding openings in the reflection hologram.

In general, it is furthermore to be noted that the forgery protection of the security element can be further increased if it has machine-readable security features, in particular having 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 additionally to be noted that a particularly high level of stability and forgery protection of the security element can be achieved if the security element has a thickness of less than or equal to 30 pm, in particular less than or equal to 25 pm. Nearly protrusion-free embedding of the security element in a substrate or value document is thus possible.

The security element according to the invention can provide its advantages in particular if it is provided on a substrate of a value document - i.e., is connected thereto. For example, a banknote, a tax stamp, a passport, driver license, or personal identification, etc., are conceivable as a value document.

Above ail, value documents can be distinguished in this regard which hâve a security element according to the invention, which extends continuously from one edge of the substrate to the opposite edge of the substrate. In this case, these can be security éléments in the form of a strip, thread, or tape.

The forgery protection of the value document can be further improved if the surfaces of the first layer of the security element and the value document are essentially identical in the haptic properties and/or individual appearance thereof. Therefore, for example, as a further conséquence, a visually recognizable opacity différence between substrate and luminescent imprint can be avoided - which it can conceal in a stable manner in the value document upon observation under white light. With regard to such an opacity différence, a printable matte lacquer layer on the security element can be distinguished in particular.

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:

Figure 1 shows a sectional view through a value document having a security element according to a first embodiment variant,

Figure 2 shows a sectional view through a value document having a security element according to a second embodiment variant, and

Figure 3 shows a top view of the security element from Figure 2.

According to Figure 1, a security element 100 is shown, which has a first polymer layer 1 and a second polymer layer 2, which are appiied to a carrier substrate 10, in particular a carrier film. A grid 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 grid printed image 3 is visually recognizable. The grid printed image 3 can in this case in particular hâve a higher opacity in comparison to the unprinted région, or can be opaque.

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 régions 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 grid printed image 3 is therefore concealed in the security element 100 upon observation under white light. The conditions under which the grid 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.

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.

In the example shown in Figure 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 grid printed image 3 from oxidation. The opacity of the grid 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.

The grid printed image 3 of the security element 100 has, as can be seen in the top view in Figure 3, red, green, and blue luminescent grid points 11, 12, and 13. A true-color luminescent grid printed image 3 thus results. The grid points 11, 12, 13 are arranged in this case in a honeycomb grid 14 of the grid 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 differentcolored grid points 11, 12, 13 are each arranged in alternating colors, and hâve a size of 10 to 500 pm, in particular 50 to 200 pm in this case.

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 Figure 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.

Figure 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.

The security éléments 100, 101 hâve a thickness of less than or equal to 30 pm, in particular less than or equal to 25 pm.

Figure 1 and Figure 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.

The security éléments 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.

Claims

Claims

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), characterized in that at least one of the two polymer layers (1,2) has an opacity at least in the région 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), in particular 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, in particular red and/or green and/or blue.

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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, in particular 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) hâve a size of 10 to 500 pm, in particular 50 to 200 pm.
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) ofthe security element (100, 101) and ofthe value document (200, 201) are essentially identical in the haptic properties and/or in the visual appearance thereof.