METHOD FOR PRODUCING A SECURITY ELEMENT COMPRISING MICRO-IMAGING ELEMENTS

Abstract

A method for producing a security element for security papers, valuable documents or the like, includes a carrier having on its top side micro-imaging elements and on its underside structures which, together with the microimaging elements, image a motif in front of the top side of the carrier; the position of the motif being is dependent on the viewing angle.

Claims

1.-7. (canceled)

8. A method for producing a security element for security papers, valuable documents, or the like, wherein a translucent or transparent carrier is provided, which includes an upper side and a lower side, a first embossing layer is applied to the upper side of the carrier, multiple micro-imaging elements are introduced into the side of the first embossing layer facing away from the carrier, a second embossing layer is applied to the lower side of the carrier, multiple embossing structures are introduced into the side of the second embossing layer facing away from the carrier, wherein the second embossing layer is at least nearly flat between the respective embossing structures, wherein the embossing structures together with the micro-imaging elements depict a motif in front of the upper side of the carrier, wherein the orientation of the motif is dependent on the viewing angle, a metallic layer is applied to the full surface on the side of the second embossing layer facing away from the carrier, wherein the metallic layer is removed from the embossing structures using an etching method and remains in areas in which the second embossing layer is at least nearly flat between the respective embossing structures.

9. The method according to claim 8, wherein in a further step, at least one ink layer is applied to the embossing structures and the areas.

10. The method according to claim 8, wherein a further metallic layer is applied to the side of the at least one ink layer facing away from the carrier.

11. The method according to claim 8, wherein the embossing structures have a height or depth of at least 2 ?m to 3 ?m.

12. The method according to claim 8, wherein the surface area of the second embossing layer is increased in relation to a surface unit of the surface of the second embossing layer in projection perpendicular to the second embossing layer of, for example, 1 mm2 in the area of the embossing structures by at least 20% in relation to the areas between the respective embossing structures, which are at least nearly flat.

13. The method according to claim 8, wherein the micro-imaging elements are formed by focusing elements such as lenses or hollow mirrors and the embossing structures are at least partially arranged in the focal plane of the micro-imaging elements.

14. The method according to claim 8, wherein the first embossing layer and the second embossing layer are each formed by an embossing lacquer, which is printed onto the carrier.

Description

[0029] In the schematic figures:

[0030] FIG. 1 shows the method according to the invention for producing a security element and in this case shows individual successive method steps in FIG. 1a to FIG. 1b,

[0031] FIG. 2 shows an exemplary embodiment of a security element produced using the method according to the invention,

[0032] FIG. 3 shows a further exemplary embodiment of a security element produced using the method according to the invention.

[0033] FIG. 1 schematically shows the method according to the invention for producing a security element. In this case, FIG. 1a shows a translucent carrier 1, which includes an upper side O and a lower side U. A first embossing layer 2 is applied to the upper side of the carrier 1 and multiple micro-imaging elements 3 in the form of micro-lenses are introduced into the side of the first embossing layer 2 facing away from the carrier 1. A second embossing layer 4 is applied to the lower side of the carrier 1 and multiple embossing structures 5 are introduced into the side of the second embossing layer 4 facing away from the carrier 1. The second embossing layer 4 is at least nearly flat in the areas 6 between the respective embossing structures 5. The side of the second embossing layer 4 facing away from the carrier 1 therefore has an at least nearly flat surface into which embossing structures are introduced, for example, by means of an embossing method known from the prior art.

[0034] In FIG. 1b, a metallic layer 7 has been applied to the entire surface on the side of the second embossing layer 4 facing away from the carrier 1 and the metallic layer 7 was washed away from the embossing structures 5 using an etching method. The metallic layer 7 is therefore only still present in the areas 6 in which the second embossing layer 4 is at least nearly flat between the respective embossing structures 5.

[0035] In FIG. 1c, an ink layer 8 has been applied to the metallic layer 7 and the areas 6. The security element displays a single-color motif in this case.

[0036] Alternatively, according to FIG. 1d, two ink layers 9 and 10 can also be applied to the metallic layer 7. The security element displays a two-color motif in this case.

[0037] FIG. 2 shows an exemplary embodiment of a security element produced using the method according to the invention, in which a further metallic layer 11 is applied over the full surface to the metallic layer 7 from FIG. 1d.

[0038] The further metallic layer 11 increases the brilliance, luminosity, color saturation, and/or contrast of the ink layers 9 and 10. Furthermore, further security features can be concealed behind the further metallic layer 11, for example, magnetic layers 12, which cannot be optically recognized by a counterfeiter.

[0039] FIG. 3 shows a further exemplary embodiment of a security element produced using the method according to the invention. The micro-imaging elements are not formed in this case by exposed lenses, which can easily be molded by a counterfeiter. Rather, the micro-imaging elements consist of lenses 12 made of highly refractive material, which are completely embedded in an embossing layer 2 made of a medium having low refraction.