Security element with colour shift effect and fluorescent features and method for production and use of same

Abstract

The invention relates to a security element having a coating consisting of a material which has an optically variable effect, in particular a colour shift effect, and has recesses that can be recognised in transmitted light, wherein the security element comprises a support substrate, a partial layer with recesses, and a layer structure that generates a colour shift effect, characterised in that the security element, on the face which has the coating consisting of the material that has an optically variable effect, comprises one or more partial coatings consisting of a layer which has colours that are transparent in visible light and fluorescent in UV light.

Claims

1. A security element, comprising: a support substrate, a partial layer with recesses, a layer structure that generates a color-shift effect formed by a coating consisting of a material having an optically variable effect and a partial layer, wherein the partial layer is formed from an opaque coating consisting of (i) a light-absorbing metallic layer consisting of non-stoichiometric aluminum oxide or stoichiometric or non-stoichiometric copper oxide, and (ii) a reflecting metallic layer, and wherein the opaque coating has light-absorbing properties on a side facing the coating consisting of the material having the optically variable effect and has metallic coloring on a side facing away from the coating consisting of the material having the optically variable effect, a coating on one side of the security element consisting of a material having an optically variable effect and recesses that can be recognized in transmitted light, and at least one partial coating on the one side consisting of a layer which has colors that are transparent in visible light and fluorescent in UV light.

2. The security element according to claim 1, wherein the material having the optically variable effect is a liquid crystal polymer layer formed from cholesteric liquid crystals or a mixture of cholesteric and nematic liquid crystals.

3. The security element according to claim 1, wherein the material having the optically variable effect is a printing ink with one or more optically variable pigments selected from the group consisting of cholesteric liquid crystal pigments, a mixture of nematic and cholesteric liquid crystal pigments, optically variable interference pigments, and iridescent pigments.

4. The security element according to claim 1, wherein the reflecting metallic layer consists of at least one metal selected from the group consisting of Al, Sn, Cu, Zn, Pt, Au, Ag, Cr, Ti, Mo, Fe, Pd, Ni, Co, and alloys thereof.

5. The security element according to claim 1, wherein the recesses that can be recognized in transmitted light are in the form of positive or negative characters, letters, numbers, images, symbols, lines, guilloche patterning of a dot grid or line grid or of a halftone grid.

6. The security element according to claim 1, wherein the layer structure that generates the color-shift effect consists of at least one layer reflecting electromagnetic waves, a polymeric spacer layer and a layer formed from metallic clusters.

7. The security element according to claim 1, wherein the colors that are transparent in visible light and fluorescent in UV light are produced from organic fluorescent dyes.

8. The security element according to claim 1, wherein the colors are coordinated with a sequence of recesses.

9. The security element according to claim 1, further comprising one or more additional partial or entire-surface layers with optical, optically active, electrically conductive or magnetic properties.

10. The security element according to claim 9, wherein security element comprises a coded magnetic layer.

11. The security element according to claim 10, the coded magnetic layer consists of magnetic materials with the same or different coercivity and/or remanence.

12. The security element according to claim 1, further comprising, on one or both sides, one or more pigmented or unpigmented protective lacquer layer(s).

13. The security element according to claim 1, further comprising, on one or both sides, a pigmented or unpigmented heat seal coating, cold seal coating or self-adhesive coating.

14. The security element according to claim 1, wherein the material has a color shift effect.

Description

(1) FIGS. 1 to 4 depict embodiments of the security element according to the invention.

(2) In said figures, 1 is a support substrate, 2 is a fluorescent layer, 3 is an LC layer, 4 is an adhesion-promoting layer, 5 is an adhesive coating, 6 is a black metallization, 7 is a black print layer, 8 is a black etch-resistant layer, 9 is a metallic layer, for example an aluminum layer, 10 is a laminated adhesive layer.

(3) The security element according to the invention is suitable for the at least partial embedding in or application onto identification, cards, banknotes or labels, seals and the like, but also as packaging material for example in the pharmaceutical, electronics and/or food industries, for example in the form of blister film, folding boxes, covers, film packaging and the like.

(4) For the application as security features, the substrates or film materials are preferably cut into strips, threads or patches, and the width of the strips or threads can preferably be 0.5-20 mm and the patches preferably have average widths and lengths of 0.3-20 mm.

(5) For the application in or on packaging, the film material is preferably cut into strips, bands, threads or patches, and the width of the threads, strips or bands is preferably 0.5-50 mm and the patches preferably have average widths and lengths of 2-30 mm.