Multi-layer body

Patent metadata

Field	Value
Publication number	US-10427368-B2
Application number	US-201715592918-A
Country	US
Kind code	B2
Filing date	May 11, 2017
Priority date	Mar 15, 2011
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

The invention relates to a multi-layer body ( 10 ) and a process for the production thereof. The multi-layer body has a first layer ( 23 ) with a first surface ( 231 ) and a second surface ( 232 ) opposite the first surface ( 231 ). The first surface ( 231 ) of the first layer ( 23 ) is defined by a base plane spanned by coordinate axes x and y, wherein a large number of facet faces ( 50 ) are molded into the second surface ( 232 ) of the first layer ( 23 ) in a first area ( 31 ). Each of the facet faces ( 50 ) is determined by one or more of the parameters F, S, H, P, Ax, Ay and Az, wherein the parameters of the facet faces ( 50 ) arranged in the first area ( 31 ) are varied pseudorandomly in the first area ( 31 ) within a variation range predefined in each case for the first area of surface and wherein a reflective second layer ( 24 ) is applied to each of the facet faces.

First claim

The invention claimed is:

1. A multi-layer body with a first layer with a first surface and a second surface opposite the first surface, wherein the first surface of the first layer defines a base plane spanned by coordinate axes x and y, wherein molded into the second surface of the first layer in a first area are a large number of facet faces, wherein each of the facet faces has a minimum dimension of more than 1 μm and a maximum dimension of less than 300 μm, wherein each of the facet faces is determined by the parameters: form F of the facet face, area size S of the facet face, spacing H of the centroid of the facet face from the base plane, position P of the centroid of the facet face in the coordinate system spanned by the x-axis and the y-axis, angle of inclination Ax of the facet face about the x-axis towards the base plane, angle of inclination Ay of the facet face about the y-axis towards the base plane and azimuthal angle Az of the facet face defined by the angle of rotation of the facet face about a z-axis perpendicular to the base plane, wherein one or more of the parameters F, S, H, P, Ax, Ay and Az of the facet faces arranged in the first area is varied pseudorandomly within a variation range predefined in each case for the first area, and wherein a reflective second layer is applied to each of the facet faces, wherein the angles of inclination Ax and Ay of the facet faces in the first area are in each case determined according to an additive superimposition of the angles of inclination Ax and Ay determined by a function F(x,y) with the pseudorandom variation of the angle of inclination Ax and/or the angle of inclination Ay within the respective variation range predefined for the first area of surface, wherein the function F(x,y) is chosen such that it varies the angles of inclination Ax and Ay to generate an optically variable first item of information.

2. A multi-layer body according to claim 1 , wherein the predefined variation range of the angles of inclination Ax and/or Ay is chosen between 0.1 times and 1.9 times the average gradient of the function F(x,y).

3. A multi-layer body according to claim 1 , wherein the function F(x,y) describes a three-dimensional free-form surface with one or more free-form elements and wherein the angles of inclination Ax and/or Ay determined by the function F(x,y) are determined by the respective surface normal of the three-dimensional free-form surface in the centroid of the respective facet face.

4. A multi-layer body according to claim 3 , wherein the function F(x,y) describes a cut section of a surface of a three-dimensional object as free-form element, wherein the minimum dimension of a free-form element relative to a projection onto the base plane is more than 2 mm, and adjacent maxima of the free-form element in the direction of the z-axis relative to a projection onto the base plane are spaced apart from each other by more than 4 mm.

5. A multi-layer body according to claim 3 , wherein the three-dimensional free-form surface comprises one or more free-form elements, producing a lens-like magnification, demagnification or distortion effect, in the form of an alphanumeric character, a geometric figure or another object.

6. A multi-layer body according to claim 3 , wherein each of the free-form elements has a minimum surface extension in the base plane of between 2 mm and 50 mm and/or wherein that the maxima of the free-form surface relative to its respective projection onto the base layer are spaced apart from each other by more than 4 mm.

7. A multi-layer body according to claim 3 , wherein the function F(x,y) is constant and differentiable in the area of each free-form element and/or wherein the function F(x,y) is composed of straight and curved areas of surface in the area of each free-form element.

8. A multi-layer body according to claim 3 , wherein the function F(x,y) describes, in the area of a free-form element, a free-form surface in the form of a lens or a lens transformed to represent an alphanumeric character, a geometric figure or another object.

9. A mufti-layer body according to claim 1 , wherein for the pseudorandom variation of one or more of the parameters F, H, P, Ax, Ay and Az within the respectively predefined variation range a parameter variation value is selected pseudorandomly from a predefined group of parameter variation values, wherein the group comprises 3 and 10 parameter variation values.

10. A multi-layer body according to claim 1 , wherein the angle of inclination Ax and/or Ay of the facet faces in the first area is varied pseudorandomly in a variation range of from −45° to +45 to achieve a glitter effect.

11. A multi-layer body according to claim 1 , wherein the azimuthal angle Az of the facet faces in the first area is varied pseudorandomly in a variation range of from −90° to +90°.

12. A multi-layer body according to claim 1 , wherein the spacing H of the centroid of the facet faces in the first area is varied pseudorandomly, wherein the difference between the maximum spacing and the minimum spacing between which the spacing H between the facet faces in the first area is varied randomly is between 0.5 μm and 8 μm.

13. A multi-layer body according to claim 1 , wherein the facet faces are arranged according to a two-dimensional grid spanned by the x- and the y-axis.

14. A multi-layer body according to claim 1 , wherein a two-dimensional grid spanned by the x- and y-axes for each of the facet faces arranged in the first area defines a normal position of the centroid of the respective facet face in the base plane and wherein the position P of each of the facet faces in the first area is determined by a pseudorandom shift from the respective normal position in x- and/or y-direction.

15. A multi-layer body according to claim 14 , wherein the limit values of the variation range of the pseudorandom shift from the respective normal position in x-direction and/or y-direction are between 0% and 100% of the dimension of the facet face in the direction of the x-axis or of the y-axis.

16. A multi-layer body according to claim 15 , wherein the variation range of the random shift is +D/2 and −D/2, wherein D is the dimension of the facet face in the direction of the x-axis or of the y-axis.

17. A multi-layer body according to claim 14 , wherein the grid width of the grid in the direction of the x-axis and/or of the y-axis is 1.5 times the dimension of the facet face in the direction of the x-axis or y-axis.

18. A multi-layer body according to claim 1 , wherein the form F of the facet face is selected from the group: square, rectangle, regular polygon, circle, conic section, random polygon.

19. A multi-layer body according to claim 1 , wherein two or more of the facet faces in the first area have a different shape.

20. A multi-layer body according to claim 1 , wherein one or more of the facet faces have the form of a symbol or a letter in order to provide a second item of optical information concealed from the human eye without the use of a tool.

21. A multi-layer body according to claim 1 , wherein one or more of the facet faces are overlaid with a diffractive structure, a zero-order diffraction structure or a nanotext.

22. A multi-layer body according to claim 1 , wherein the second layer has a thin-film layer system which has one or more spacer layers the layer thickness of which is chosen such that the thin-film layer system generates, by means of interference of the incident light, a color shift effect dependent on the view

Assignees

• Ovd Kinegram Ag

Inventors

• Tompkin Wayne Robert
• Walter Harald

Classifications

• B42D25/29 Primary

  Securities; Bank notes · CPC title

• B32B3/30

  characterised by a layer formed with recesses or projections, e.g. {hollows, grooves, protuberances, ribs (apertured layer B32B3/266; layer with cavities or internal voids B32B3/26)} · CPC title

• B32B2551/00

  Optical elements · CPC title

• Y10T428/24355

  Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.] · CPC title

• B42D25/45

  Associating two or more layers · CPC title