Multi-layer body and method for the production thereof

Patent metadata

Field	Value
Publication number	US-9975370-B2
Application number	US-201515308865-A
Country	US
Kind code	B2
Filing date	May 7, 2015
Priority date	May 7, 2014
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A method for the production of a multilayer body, in particular a security element, includes: a) producing a metal layer on a substrate; b) partial demetalization of the metal layer to form a first item of optical information in a first area of the multilayer body; c) applying a partial lacquer layer in a second area of the multilayer body to form a second item of optical information, wherein the partial lacquer layer extends at least partially beyond the metal layer; d) structuring the partial metal layer in the second area using the partial lacquer layer as mask.

First claim

The invention claimed is:

1. A method for the production of a multilayer body in the form of a security element, comprising the following steps:
a) producing a metal layer on a substrate;
b) partial demetalization of the metal layer to form a partial metal layer comprising a first item of optical information in a first area of the multilayer body;
c) applying a partial lacquer layer in a second area of the multilayer body to form a second item of optical information, wherein the partial lacquer layer extends at least partially beyond the metal layer;
d) structuring the partial metal layer in the second area using the partial lacquer layer as mask, wherein the partial metal layer is either selectively retained or selectively removed in the areas which are covered by the partial lacquer layer.

2. The method according to claim 1 , wherein the partial demetalization in step b) takes place through etching.

3. The method according to claim 2 , wherein the partial lacquer layer is an etch resist, or comprises at least one etch resist.

4. The method according to claim 3 , wherein the etch resist is a lacquer that comprises:
binders;
colored or non-colored pigments and/or effect pigments;
thin-layer film systems;
cholesteric liquid crystals;
dyes; and/or
metallic or non-metallic nanoparticles.

5. The method according to claim 1 , wherein before the application of the partial lacquer layer in step c), the metal layer is partially demetalized in the second area.

6. The method according to claim 5 , wherein the partial demetalization of the metal layer in the second area takes place through etching.

7. The method according to claim 6 , wherein, in the second area, an etching base, is printed onto the metal layer by flexographic printing.

8. The method according to claim 6 , wherein, before the etching, a photoresist is applied to the second area and is exposed using an exposure mask.

9. The method according to claim 8 , wherein the exposure mask is formed by a partial lacquer layer applied to the substrate before the application of the metal layer.

10. The method according to claim 6 , wherein, before the etching, an etch resist is applied partially to the second area and is removed again after the etching.

11. The method according to claim 5 , wherein the partial demetalization of the metal layer in the second area takes place through lift-off.

12. The method according to claim 5 , wherein the partial demetalization of the metal layer in the second area takes place through laser ablation.

13. The method according to claim 5 , wherein the partial demetalization of the metal layer in the second area takes place through printing of a partial oil layer before the application of the metal layer.

14. The method according to claim 1 , wherein the substrate is or comprises a replication layer with a surface relief formed in a surface facing the metal layer.

15. The method according to claim 14 , wherein the surface relief introduced into the replication layer forms a hologram, a linear or crossed sinusoidal diffraction grating, a linear or crossed single- or multilevel rectangular grating, a zero-order diffraction structure, an asymmetrical relief structure, a blazed grating, an isotropic or anisotropic matt structure, or a light-diffracting and/or light-refracting and/or light-focusing micro- or nanostructure, a binary or continuous Fresnel lens, a binary or continuous Fresnel freeform surface, a microprism structure or a combination structure thereof.

16. The method according to claim 14 , wherein the surface relief comprises a partial area with a depth-to-width ratio of from 0.15 to 1.5, which is complementary to the first item of optical information.

17. The method according to claim 16 , wherein, for the partial demetalization of the metal layer in the first area, a photoresist is applied to the metal layer and is exposed from the side of the substrate and the metal layer is then partially demetalized by etching.

18. The method according to claim 1 , wherein at least one further partial lacquer layer is applied to the multilayer body to form at least one further item of optical information.

19. The method according to claim 18 , wherein the at least one further partial lacquer layer comprises:
colored or non-colored pigments and/or effect pigments;
thin-layer film systems;
cholesteric liquid crystals;
dyes; and/or
metallic or non-metallic nanoparticles.

20. The method according to claim 19 , wherein the colorants can be excited in the ultraviolet and/or infrared spectrum to fluorescence and/or phosphorescence in the visible spectrum.

21. The method according to claim 1 , wherein the partial lacquer layer and/or the at least one further partial lacquer layer is applied by intaglio printing, flexographic printing, screen printing, pad printing, offset printing, letterpress printing, ink-jet printing and/or laser printing.

22. The method according to claim 1 , wherein the partial lacquer layer and/or the at least one further partial lacquer layer is radiation-cured by UV or electron-beam radiation.

23. The method according to claim 1 , wherein at least one individualization feature is applied to the multilayer body by ink-jet and/or laser printing.

24. A multilayer body in the form of a security element, wherein the multilayer body comprises a substrate, a partial metal layer and a partial lacquer layer, and wherein the partial metal layer forms, in a first area, a first item of optical information and the partial lacquer layer forms, in a second area, a second item of optical information and the partial lacquer layer is arranged in the second area in register with the partial metal layer, wherein the partial lacquer layer extends both into areas which are covered by the partial metal layer and into areas not covered by the partial metal layer.

25. The multilayer body according to claim 24 , wherein the substrate is or comprises a replication layer with a surface relief, which is formed in a surface facing the partial metal layer.

26. The multilayer body according to claim 25 , wherein the surface relief introduced into the replication layer forms a hologram, a linear or crossed sinusoidal diffraction grating, a linear or crossed single- or multilevel rectangular grating, a zero-order diffraction structure, an asymmetrical relief structure, a blazed grating, an isotropic or anisotropic matt structure, or a light-diffracting and/or light-refracting and/or light-focusing micro- or nanostructure, a binary or continuous Fresnel lens, a binary or continuous Fresnel freeform surface, a microprism structure or a combination structure thereof.

27. The multilayer body according to claim 25 , wherein the surface relief comprises a partial area with a depth-to-width ratio of from 0.15 to 1.5, which is complementary to the first item of optical information.

28. The multilayer body according to claim 24 , wherein the substrate comprises a wax layer and/or a release layer and/or a protective lacquer layer.

29. The multilayer body according to claim 28 , wherein a layer thickness of the replication layer and/or of the protective lacquer layer is 0.3 μm to 3 μm.

30. The multilayer body according to claim 28 , wherein a layer thickness of the wax layer and/or of the release layer is 0.01 μm to 0.3 μm.

31. The multilayer

Assignees

• Ovd Kinegram Ag

Inventors

• Karrer Walker Reto
• Schilling Andreas
• Staub Rene
• Streb Christina
• Saxer Christian

Classifications

• B42D25/337

  Guilloche patterns · CPC title

• B42D25/21

  for multiple purposes · CPC title

• B41M3/148

  Transitory images, i.e. images only visible from certain viewing angles · CPC title

• B42D25/445

  using chemical means, e.g. etching · CPC title

• B41M3/14

  Security printing {(securities B42D25/29)} · CPC title