Security element and method for producing the same
View Patent ↗The present invention relates to a security element ( 12 ) for protecting valuable articles, having a thin-film element ( 30 ) that has a color-shift effect and that includes an absorber layer ( 36 ) having gaps ( 38 ) in the region of which no color-shift effect is perceptible, and a relief pattern ( 26 ) that is arranged only in gapped absorber layer regions ( 38 ) below the thin-film element ( 30 ).
1. A security element for securing valuable articles, having
an embossing lacquer layer having a relief pattern,
a thin-film element having a color-shift effect and including a reflection layer, an absorber layer and a dielectric spacing layer disposed between the reflection layer and the absorber layer, wherein the reflection layer is arranged between the embossing lacquer layer and the dielectric spacing layer,
wherein the thin-film element is arranged over the embossing lacquer layer in the sequence reflection layer, dielectric spacing layer and absorber layer, thus providing the security element with a layer structure comprising in order the embossing lacquer layer, the reflection layer, the dielectric spacing layer, and the absorber layer;
wherein the absorber layer of the thin-film element has gaps in the region of which no color-shift effect is perceptible, and
wherein the relief pattern is arranged only in gap regions of the absorber layer below the thin-film element.
2. The security element according to claim 1 , characterized in that the gaps in the absorber layer are present in the form of characters, patterns or codes.
3. The security element according to claim 1 , characterized in that the relief pattern constitutes a diffractive pattern, or an achromatic pattern.
4. The security element according to claim 1 , characterized in that the thin-film element includes at least a first absorber layer, a second absorber layer and a dielectric spacing layer arranged between the two absorber layers, at least one of the absorber layers including said gaps.
5. The security element according to claim 1 , characterized in that in gap regions of the absorber layer, the dielectric spacing layer also has gaps.
6. The security element according to claim 1 , characterized in that the thin-film element comprises a reflection layer having gaps in the form of patterns, characters or codes that form transparent or translucent areas in the thin-film element.
7. The security element according to claim 1 , characterized in that over the thin-film element is arranged, in some regions, a transparent phase-delay layer that forms a phase-shifting layer for light from the visible wavelength range.
8. The security element according to claim 7 , characterized in that the phase-delay layer is present in the form of patterns, characters or a code.
9. The security element according to claim 7 , characterized in that the phase delay of the phase-delay layer corresponds to a path difference between λ/6 and λ/2 for light from the visible wavelength range.
10. The security element according to claim 7 , characterized in that the phase-delay layer forms, at least in sub-regions, a λ/4 layer for light from the visible wavelength range.
11. The security element according to claim 7 , characterized in that the phase-delay layer is formed from nematic liquid crystal material.
12. The security element according to claim 1 , characterized in that, in some regions, a semi-transparent ink layer is arranged over the thin-film element, the color impression of the thin-film element when viewed under predetermined viewing conditions being adapted to the color impression of at least one sub-region of the semi-transparent ink layer.
13. The security element according to claim 12 , characterized in that, in a spectral range in which the color impression of the thin-film element is adapted to the color impression of the semi-transparent layer, the semi-transparent ink layer exhibits a transmittance between 30% and 95%.
14. The security element according to claim 12 , characterized in that the semi-transparent ink layer is present in the form of characters, patterns or codes.
15. The security element according to claim 12 , characterized in that the semi-transparent ink layer substantially preserves the polarization state of light from the visible wavelength range passing through.
16. The security element according to claim 12 , characterized in that the semi-transparent ink layer comprises multiple sub-regions having different color impressions, and the color impression of the thin-film element when viewed under predetermined viewing conditions is adapted to the color impression of at least one of the sub-regions.
17. A method for manufacturing the security element according to claim 1 , comprising the steps in which
the embossing lacquer layer is applied to a substrate, and is embossed in the form of a relief pattern in a sub-region of the embossing lacquer layer,
the thin-film element having a color-shift effect is arranged over the embossing lacquer layer, the absorber layer of the thin-film element being provided with gaps in the regions that are provided with the relief pattern.
18. The method according to claim 17 , characterized in that, in some regions, a semi-transparent ink layer is arranged over the thin-film element, the color impression of the thin-film element when viewed under predetermined viewing conditions being adapted to the color impression of at least one sub-region of the semi-transparent ink layer.
19. The method according to claim 18 , characterized in that the semi-transparent ink layer is imprinted.
20. The method according to claim 17 , characterized in that over the thin-film element is arranged, in some regions, a transparent phase-delay layer that forms a phase-shifting layer for light from the visible wavelength range.
21. The method according to claim 20 , characterized in that the phase-delay layer is imprinted on the thin-film element.
22. The method according to claim 20 , characterized in that the phase-delay layer is applied to a substrate foil and is transferred to the thin-film element.
23. The method according to claim 17 , characterized in that a phase-delay layer is applied to the substrate before application of the embossing lacquer layer.
24. A security paper for manufacturing security or value documents, that are furnished with the security element according to claim 1 .
25. The security paper according to claim 24 , characterized in that the security paper comprises a carrier substrate composed of paper or plastic.
26. A data carrier having the security element according to claim 1 .
27. A use of the security element according to claim 1 , of a security paper furnished with the security element, or of a data carrier having the security element for securing goods against counterfeiting.