WO2017028954A1

WO2017028954A1 - Value document

Info

Publication number: WO2017028954A1
Application number: PCT/EP2016/001401
Authority: WO
Inventors: Michael Böhm; Michael Rahm; Theodor Burchard; Ralf Liebler; Christian Fuhse
Original assignee: Giesecke & Devrient Gmbh
Priority date: 2015-08-19
Filing date: 2016-08-17
Publication date: 2017-02-23
Also published as: EP3337674A1; EP3337674B1; CN108025584B; DE102015010945A1; CN108025584A

Abstract

The invention relates to a layer structure for a security element, in particular a value document, comprising a plurality of distributed mirror surfaces for connecting to a value document substrate, wherein the plurality of distributed mirror surfaces is designed to cover an image, wherein the distributed mirror surfaces are formed by reflective regions applied on a relief with a plurality of relief elements, and the reflective regions cover 10-90% of the surface of the relief, or the distributed mirror surfaces are formed by a highly refractive reflective layer which is applied on a relief with a plurality of relief elements, wherein when viewing in incident light at a first viewing angle incident light reflects at the distributed mirror surfaces, whereby the identifiability of the image is suppressed, and when viewing in incident light at a second viewing angle the image is identifiable. The invention also relates to a value document having a layer structure and a method for producing same.

Description

value document

The invention relates to a layer structure, a value document with a layer structure and a method for producing a value document.

Value documents within the meaning of the invention include banknotes, stocks, bonds, certificates, vouchers, checks, air tickets, high-quality entrance tickets, labels for product security, credit or debit cards, but also other forgery-prone documents, such as passports, ID cards or other identity documents.

Value documents, in particular banknotes, are usually produced from paper substrates which have special security features, such as a security thread at least partially incorporated into the paper and a watermark. Paper substrates are typically made from natural polymer such as cotton fibers, synthetic polymer such as polyamide fibers, or combinations of natural and synthetic polymers. Furthermore, value documents can also be made entirely of synthetic polymer. Finally, value documents can be constructed, for example, in multiple layers. For example, a value document may comprise a natural polymer value document substrate, after applying various security features to / in that value document substrate, films / layers of synthetic polymer are applied. Security features typically provide particular tactile and / or visual effects. Tactile security elements can be, for example, tactile embossments or reliefs. Optical security elements can be, for example, holograms or Farbkippef- effects. It is an object of the present invention to provide a security element which can be easily manufactured and connected to a value document substrate while providing a very visible optical effect.

This object is solved by the subject matters of the independent claims. Preferred embodiments are defined in the dependent claims. A first aspect of the invention relates to a layer structure for a security element, in particular a value document, comprising a plurality of distributed mirror surfaces for connection to a value document substrate, wherein

the plurality of distributed mirror surfaces is adapted to cover a representation, wherein

the distributed mirror surfaces are formed by reflection areas, which are applied on a relief with a plurality of relief elements, and cover the reflection areas between 10% to 90% of the surface of the relief, or the distributed mirror surfaces by a high refractive reflection layer, which on one Relief applied with a variety of relief elements are formed, taking

when viewed in incident light at a first viewing angle reflected light at the distributed mirror surfaces, whereby the recognizability of the representation is suppressed, and

- When viewed in incident light at a second viewing angle, the representation is recognizable.

Preferably, the reflection areas cover between 25% to 75% of the surface of the relief. Further preferably, the reflection ranges cover 30% to 50% of the surface of the relief. Preferably, the reflection areas cover 50% of the surface of the relief. Preferably, the reflection areas are opaque reflection areas. In particular, the distributed mirror surfaces are formed by the combination of reflection areas and the relief.

In particular, when viewing the layer structure in incident light at a first viewing angle - in which incident light is reflected at the distributed mirror surfaces, and thus the visibility of the representation is suppressed - a surface gloss for a viewer due to the reflection at the distributed mirror surfaces visible. The gloss or the light reflection is so intense that the applied representation by the viewer can hardly or no longer be perceived.

In particular, when viewing the layer structure in incident light at a second viewing angle, the representation of the mirror surfaces can be released, and therefore the representation is visible to a viewer. In particular, preferably, when viewing the layer structure in incident light at a second viewing angle, a disturbance in the viewing of reflections on the mirror surfaces is avoided.

Preferably, the representation is applied to / on the layer structure. In particular, the representation is preferably part of the layer structure. Alternatively, the representation is applied to a major surface of the value document substrate and the layer structure covers the representation. A value document substrate comprises first and second major surfaces, which face each other and give information to a viewer, such as denomination, watermarks, etc., again.

In particular, the term "a representation on a major surface of the value-document substrate" is to be understood as meaning that a representation is applied to a major surface of the value-document substrate by means of printing technology. on a main surface applied representation are understood. This may, according to one embodiment, include that the means for forming the representation, such as printing inks, at least partially penetrate into the value document substrate. According to an alternative embodiment, the means for forming the representation do not penetrate into the value document substrate but are merely in surface contact with at least one of the major surfaces.

In particular, the term "a plurality of distributed mirror surfaces on a main surface covering the representation, the representation being obscured by the distributed mirror surfaces as a function of a viewing angle" means that the representation between one of the major surfaces of the value document substrate and the layer element In other words, the plurality of distributed mirror surfaces are arranged in a thickness direction over the representation.

Further preferably, the layer structure comprises a carrier substrate. Preferably, the distributed mirror surfaces are arranged on / above the carrier substrate. Preferably, the representation is arranged between the carrier substrate and the distributed mirror surfaces. Alternatively, the carrier sub- strat arranged between the representation and the distributed mirror surfaces. As an alternative, the distributed mirror surfaces are arranged between the carrier substrate and the representation. Providing the representation on / on the layer structure has the advantage that the combination of distributed mirror surfaces and representation can also be achieved precisely during wobbling application to or wobbling introduction into a value document substrate. This case is present in particular when the layer structure is designed as a security thread / ribbon.

The carrier substrate is preferably transparent. The carrier substrate is preferably a film element or a film-like. For example, the carrier substrate comprises polyethylene terephthalate (PET) and / or polypropylene (PP). Preferably, the layer structure is firmly connected to the value document substrate.

In a further embodiment, the carrier substrate is removed before or after the application of the layer structure to a value document substrate. In this case, no representation is firmly connected to the carrier substrate.

Preferably, each relief element has an orientation which is defined by an angle of inclination and an azimuth angle. In other words, the orientation of a relief element is determined by its inclination angle and its azimuth angle.

Preferably, each relief element has an angle of inclination in the range of 0 ° to 60 °. In particular, preferably, the relief spans a plane. In particular, preferably, a relief layer surrounding the relief tensions the plane. The angle of inclination of a relief element corresponds to the angle enclosed by the surface normal of the plane and the surface normal of a relief element. The azimuth angle indicates the orientation of the surface normal within the plane defined by the relief.

Preferably, some relief elements have a central orientation corresponding to a fixed angle of inclination and a fixed azimuth angle. Further preferably, further relief elements on a deviation between 0 ° to 15 ° from the specified angle of inclination. Alternatively or additionally, the further relief elements on a deviation between 0 ° to 15 ° from the specified azimuth angle.

In particular, a deviation, based on the angle of inclination, the difference between the inclination angle of the relief element with average orientation and the inclination angle of the relief element with a different inclination angle can be understood.

Furthermore, a deviation relative to the azimuth angle may be understood to mean the difference between the azimuth angle of the middle orientation relief element and the azimuth angle of the relief element with a deviating azimuth angle.

For example, the angle of inclination of the surface normal of a middle orientation relief element may be 35 °. A relief element with a deviation of 3 ° from this central orientation (35 °) can then have an angle of the surface normal of 32 ° or 38 °. For example, the azimuth angle of the surface normal of a middle orientation relief element may be 0 °. A relief element with a deviation of 3 ° from this azimuth angle (0 °) can then have an azimuth angle of 3 ° or 357 °.

For example, a middle orientation relief element may have an inclination angle of 15 ° and an azimuth angle of 40 °. A relief element with a deviation of 3 ° from this central orientation (15 °, 40 °) then indicates e.g. an inclination angle of 12 ° or 18 ° or an azimuth angle of 37 ° or 43 °.

Advantageously, it can be avoided by the variation around the average orientation that a viewer perceives disturbing diffraction effects.

Further advantageously, it can be achieved by the variation around the average orientation that the viewing angle at which the recognizability of the representation is suppressed is increased. Consequently, a viewer can not perceive the display even if the viewing angle varies by a few degrees.

Preferably, a plurality of relief elements having a first average orientation or a deviation from this first average orientation form a first group. Further preferably, a plurality of relief elements having a second average orientation or a deviation from this second average orientation form a second group. Preferably, the mean orientation of the first group and the mean orientation of the second group differ. The average orientation of the first group and the average orientation of the second group preferably differ by at least 5 °, in particular preferably by at least 10 °. Particularly preferably, the angle of inclination of the first group and the angle of inclination of the second group differ by at least 5 °, in particular preferably by at least 10 °. In particular, the azimuth angle of the first group and the azimuth angle of the second group preferably differ by at least 5 °, in particular preferably by at least 10 °.

Advantageously, the viewing angles of two groups differ. Thus, a portion of the representation covered by a first group is exposed to one observer at a particular viewing angle, while another portion of the representation, which is covered by a second group, is obscured to a viewer at that particular viewing angle ,

As a result, the representation (s) of the representation covered by multiple groups of the distributed mirror surfaces is suppressed or released at different viewing angles. Therefore, by moving the value document substrate such as tilting and / or rotating the value document substrate, it is possible to successively see a (other) part of the representation. The mirror surfaces of the second group can suppress the recognizability of the entire representation or a region of the representation by reflection. When a first region of the representation of (the mirror surfaces) of a first group is covered and a second region of the representation is covered by the second group, is in incident light

at a first viewing angle through the first group, the first area is not recognizable and the second area is recognizable,

- Under a second viewing angle, the first area and the second area of the representation recognizable and

- Under a third viewing angle by the second group of the second area not visible and the first area recognizable.

When the whole representation of (the mirror surfaces) of a first group is covered and a region of the representation is covered by a second group, it is in incident light

- under a first viewing angle through the first group the whole presentation is not recognizable,

- Under a second viewing angle the whole presentation recognizable and

- Under a third viewing angle by the second group, the area of the representation is not recognizable.

The mentioned presentation areas could be regarded as independent representations, they are in particular perceptible and suppressible. The characteristics and effects valid for representations apply analogously to presentation areas. The effect of the mirror surfaces of the second group (n) is analogous to the effect of the first group; in particular, only the viewing angle is different and optionally only the portion of the representation covered by the second group is affected. Additional display areas can each have their own (second) Groups are covered and suppressed in your recognizability depending on the viewing angle.

In the following three paragraphs, some variants are described, in which the mirror surfaces of the second group (s) are provided for supplementing the representation. The second groups do not suppress the presentation or a separate presentation area.

The mirror surfaces on the first group of relief elements suppress the recognizability of the representation. The mirror surfaces on the second group (s) of relief elements produce an additional perceivable element for the viewer. The mirror surfaces of the second group appear to the viewer as a (metallic, preferably silver) shiny surface. The additionally perceptible element can in particular be independent of the representation and / or adapted to the representation. For example, if the representation includes (own / primary) information (eg, a number, a letter, a shape, or a pattern) and a background, the second group may cover at least a portion of the background and / or provide additional information. For example, the second group can form an outer edge for the representation or form a border of the information, in each case with a constant edge width or varying edge width.

In order for the mirror surfaces of the second group to appear to the viewer as a (metallically) shiny surface (without suppressing the recognizability of the entire representation), different approaches are conceivable. Preferably, the mirror surfaces of the second group have a lower percentage coverage of the relief and / or a smaller total area than the mirror surfaces of the first group. The percentage (or total area) is at least a factor of 2 lower for the second group (p2 <= pl / 2), preferably the factor 3 (p2 <= pl / 3), particularly preferably the factor 5 (p2 <= pl / 5). Preferably, the surface of the second groups of filigree surface elements such as lines and / or points. In this case, the width of a surface element in the direction of its smallest extent is preferably less than 300 μηπ, more preferably less than 100 μπι. Alternatively or additionally, mirror surfaces of the second group may be less reflective (semitransparent, dull, different material) than the mirror surfaces of the first group.

The following behavior occurs with complementary (instead of "suppressing") second groups: in reflected light at the first viewing angle, the representation is not recognizable The reflections from the mirror surfaces on the first group of relief elements suppress the recognizability of the entire representation In the incident light at a third viewing angle, the portion of the image uncovered by the mirror surfaces of the second group is recognizable When viewed at the third viewing angle, the (non-suppressing) mirror surfaces of the second group produce for the viewer the additionally perceptible element.

Preferably, the second groups complement the representation in a third viewing angle, wherein, when moving about a given axis, the second / third viewing angle is between the first and the third and the first and the second viewing angle. When changing the viewing angle in a predetermined direction, for example, by a tilting or rotational movement about a predetermined axis, thus successively suppresses the presentation, recognizable and supplemented recognizable or suppressed, added recognizable and recognizable.

The other comments apply again generally, ie in particular for all groups or independently of any second group.

The reflection ranges preferably cover between 10% to 90%, particularly preferably between 25% to 75%, in particular between 30% to 50%, of the surface of the relief visible from the first viewing angle.

Further preferably, a relief element has a feature size in the range of 0 μτη to 50 μιη. Further preferably, a relief element has a structure wide in the range of 0.5 μηι to 10 μπι, more preferably 1 μηι - 5 μιη on. Furthermore, preferably, a relief element has a structural height of less than or equal to 20 μm.

Alternatively or additionally, the relief is formed by an embossed structure in a stamping layer. The relief can be formed by an embossed structure in a stamping layer.

Alternatively or additionally, a relief element may have a substructure. A substructure may e.g. Hologram structures or sub-wavelength structures. Preferably, a plurality of relief elements have a substructure which together form information so that information such as a text, pattern, value number can be recognized by a viewer.

Preferably, a patterned reflective layer defines the reflective areas and non-reflective areas. Preferably, the structured Reflection layer a reflection layer with recesses. Each recess defines a non-reflective area.

In particular, non-reflective regions are to be understood as regions which have a lower degree of reflection than the reflection regions under the same light incidence conditions.

In particular, the non-reflective regions may be non-opaque regions.

Particularly preferably, the structured reflection layer is applied as a coating on the relief.

Preferably, the recesses have a width of less than or equal to 300 μπι. Alternatively or additionally, adjacent recesses have a distance of less than or equal to 300 μη. Preferably, adjacent recesses have a regular width. Preferably, adjacent recesses have a regular spacing. Particularly advantageously, the recesses are so small that they can not be resolved individually with the human eye, and then exhibit e.g. dimensions less than about 100 μm in at least one direction. on.

Preferably, the presentation is substantially completely visible to a viewer. In particular, the term "substantially completely visible" is understood to mean that a viewer has the impression that he can see the representation or the part of the representation completely - ie undisturbed, ie without rastering or missing parts. Preferably, a structured reflection layer defines the reflection regions and non-reflective regions, the reflection regions being present as islands on the relief. Each island is surrounded by a non-reflective area.

Preferably, a stamping layer covers the representation. The embossed layer has an embossed structure which comprises the relief with the relief elements. At least one structured reflection layer is applied to the relief elements. The structured reflection layer is preferably a metal layer. Alternatively or additionally, at least partially a structured high-index layer is applied as a reflection layer on the relief elements. The structured high refractive index layer is preferably a high refractive index dielectric layer or high refractive index semi-metallic layer.

Alternatively or additionally, an at least semitransparent high-refractive-index layer is applied over the entire surface of the relief elements as a reflection layer. The high refractive index layer is preferably a high refractive dielectric layer or high refractive semimetallic layer.

Preferably, a mirror surface is formed by a reflection layer on / above a relief element. In other words, a combination of relief element and reflection layer constitutes a mirror surface. The reflection layer is preferably at least one metal layer and / or at least one high-index layer and / or a multilayer coating which changes color upon tilting. Such multilayer coatings For example, it is possible to use a three-layer absorber-dielectric-reflector system.

As materials for the metal layer as the reflection layer, preference is given to using aluminum, silver, copper, chromium, nickel, iron or alloys of these metals.

The metal layer is preferably applied by means of a vapor deposition method. Alternatively, the metal layer is applied in the form of a metal particle dispersion. In this case, metal particles are present as platelets or so-called flakes in a binder. This metal particle dispersion or flakes can be applied, for example, by means of a printing process. The flakes are so small or thin that they conform to or follow the structure of the relief.

Preferably, the high refractive index (dielectric) layer has a thickness in the range of 10 nm to 200 nm as a reflection layer of a distributed mirror surface. Preferably, the refractive index difference between the embossing layer and the refractive layer reflective layer is at least 0.15, preferably at least 0.3. As materials for the high refractive index layer, zinc sulfide and / or titanium oxide are preferably used.

Preferably, the islands have a width of less than or equal to 300 μπι. Preferably, adjacent islands have a distance from one another of less than or equal to 300 μιτι. Preferably, adjacent islands have a regular width. Preferably, adjacent islands have a regular spacing. Preferably, the distributed mirror surfaces are designed such that a viewer can not perceive diffraction effects. The structuring of the structured reflection layer is preferably below the resolution limit of the human eye, so that a viewer can not distinguish the reflection regions and the non-reflective regions from one another.

Preferably, the distributed mirror surfaces are formed as depressions in the relief. Alternatively or additionally, the distributed mirror surfaces are formed as elevations in the relief. Preferably, the representation is a representation prepared by printing technology. Alternatively or additionally, the representation has laser-generated elements, such as color changes and / or blackening produced by laser beam. Alternatively or additionally, the representation is based on translucent colors. Alternatively or additionally, the representation is based on scattering colors. Alternatively or additionally, the representation is based on opaque colors. Alternatively or additionally, the representation, in particular UV-active, luminescent colors (fluorescence, phosphorescence or anti-Stokes radiation). Alternatively or additionally, the illustration is based on a reflection layer, preferably a metal layer. Further preferably, the illustration

Openings on, so that so-called. Clear text or negative signs are present. In particular, the recesses are transparent or translucent, so that a see-through effect can be seen in the region of the recesses. Alternatively or additionally, the representation includes a foreground with a motif and an opaque background. Furthermore, the representation is preferably based on a combination of one or more translucent colors or color layers and an (additional) reflection layer. The translucent color (s) or color layer (s) is / are preferably arranged between the embossing layer and the (additional) reflection layer. These (additional The reflection layer is not the reflection layer of the distributed mirror surfaces. Further preferably, the value document is in the area opaque, which has the representation. Preferably, the depressions or elevations are leveled into a leveling layer. By way of example, a leveling layer may be a primer layer and / or a protective lacquer layer and / or a heat sealing lacquer layer. Advantageously, the previously described layer structure allows the reflection regions to be applied to the relief without high requirements on the register accuracy or tolerances. In particular, no elaborate coating methods must be used, wherein the reflection layer is directed to apply to the relief. Furthermore, it is advantageous that the relief can be produced very precisely, so that there are only slight deviations from a previously defined relief shape. As a result, the viewing angles or viewing angle ranges can be set very precisely. In comparison, magnetically orientable pigments in a binder can not be aligned or oriented nearly as accurately. In particular, abrupt changes in orientation are not possible with such pigments. Furthermore, such pigments also have a relatively large size distribution. Finally, the distribution of the pigments in the binder can almost not be affected. This results in particular the advantage that a security element can be provided, which can be produced simultaneously quickly and inexpensively and at the same time provides a good optical effect. It is also advantageous that the reflection layer can basically be applied to each relief element. In contrast, it is necessary for the conventional lamellar effect only on certain lamellae, ie flanks, a relief to apply the reflective layer. In the case of conventional lamellar structures, in the case of a relief with a sawtooth profile, one edge of the sawtooth must remain free of the reflection layer, while only the other edge is to be coated with the reflection layer. Therefore, the flanks must be coated very precisely, whereby the production cost is very large.

In addition, it is advantageous that the reflection areas only have to cover the surface of the relief to a relatively small extent, namely less than 90%, so that the visibility of the representation is nevertheless substantially suppressed in suitable viewing situations. Such viewing situations essentially occur when light is reflected at the distributed mirror surfaces and enters the eye of the observer. In this case, the brightness of the light reflected at the distributed mirror surfaces outshines the light, which is reflected on the display and incident on the eye of the viewer. Thus, the effect is advantageously not dependent on complete shielding of the image.

With further advantage, the layer structure described can be produced very thinly, so that the layer structure is suitable for a security thread, a security tape as well as for the so-called T-LEAD (transfer strip) or L-LEAD (laminate strip).

Furthermore, it is advantageous that the layer structure in combination with other security features, such as holograms, micromirror arrangements, such as in the security thread RollingStar®, arching effects, subwavelength structures, Colorshift effects, fluorescence features, and / or electrical or magnetic security features can be used. For example, the previously described layer structure and additionally a hologram can be provided on a security thread or strip.

This combination can coexist, i. On a security thread or strip, a layer structure according to the invention is present in a first region and, for example, a hologram or a sub-wavelength structure in another region.

Advantageously, the safety features mentioned in the penultimate paragraph can also be integrated directly into a layer structure according to the invention. In addition, substructures, for example hologram structures or sub-wavelength structures, can be applied / provided directly on the relief elements or directly on the reflection regions of the mirror surfaces, such sub-structures being particularly suitable It is also particularly advantageous to provide such subwavelength structures on at least some of the distributed mirror surfaces, so that incident light at a first viewing angle is not only reflected at the distributed mirror surfaces when viewed in reflected light, but also at the same time In other words, the subwavelength structures influence the color of the reflected light, and the color of the reflected light can also be rich be different, for example, by partially different sub-wavelength structures that produce different colors. Thus, a viewer can not perceive only a homogeneous monochrome reflection. The subwavelength Structures can be distributed to different mirror surfaces in such a way that an observer can perceive several colors. Alternatively or additionally, the substructures, such as subwavelength structures or holograms, can be distributed to different mirror surfaces in such a way that, for example, additional information (eg text train, symbol or value number) can be recognized by a viewer.

Another aspect relates to a value document with

a value document substrate having first and second major surfaces facing each other,

a representation on one of the major surfaces of the value document substrate, and

a layer structure according to one or more of the above-described embodiments, wherein the layer structure is applied to the first main surface of the value document substrate.

Preferably, the document of value is a banknote. A value document substrate includes, for example, paper substrate (s), such as synthetic and / or natural polymers, in particular polymer fibers. Hybrid substrates, for example composed of paper and plastic layers, are also used for value document substrates. In particular, a value document can have a value-document substrate, such as single-layer or multi-layer paper layers, into / onto which the layer structure according to the invention is then applied, and then one or more plastic layers are applied.

In particular, the statements on the first aspect and its preferred embodiments apply analogously to the value document. According to one embodiment, the layer structure is also applied on the first main surface of the value document substrate. According to a further embodiment, the layer structure is applied to the second main surface of the value document substrate.

Another aspect relates to a method for producing a value document comprising the steps:

Providing a value document substrate having first and second major surfaces facing each other;

- Applying a representation on one of the main surfaces;

Depositing a layer having a plurality of distributed mirror surfaces on the first major surface that cover the representation, wherein the distributed mirror surfaces are formed by reflection regions that are applied on a relief having a plurality of relief elements, the relief inclined surfaces with respect to the first major surface and cover the reflection areas between 10% to 90% of the surface of the relief, wherein

upon reflection of the first main surface in incident light at a first viewing angle, incident light is reflected at the distributed mirror surfaces, thereby suppressing the visibility of the image, and

when viewing the first main surface in incident light at a second viewing angle the representation is recognizable. Preferably, the step of applying a plurality of inclined mirror surfaces comprises one or more of the following steps:

Producing a layer having a relief with a plurality of relief elements applied to the value document substrate; Producing a structured reflection layer on the relief, preferably by means of metal transfer, printing, physical or chemical vapor deposition methods;

Producing a reflection layer on the relief, preferably by means of metal transfer, printing, physical or chemical vapor deposition; and patterning the reflective layer by selectively removing the reflective layer in predetermined areas of the relief, preferably by metal transfer, separation winding, etching, washing or lasing.

The relief is preferably produced by producing an embossed structure in a stamping layer.

In particular, the statements on the first aspect and its preferred embodiments apply in an analogous manner to the method.

The invention will be explained below with reference to preferred embodiments in conjunction with the accompanying figures, in the representation of a scale and proportionate reproduction has been omitted in order to increase the clarity.

Show it:

Fig. La, lb is a schematic sectional view of a detail of a

Value document with security element according to a variant;

Fig. Lc is a perspective view of a value document with a

Safety element; a schematic representation in plan view of a value document with security element according to a variant when viewed at a first viewing angle; a schematic representation in plan view of a document of value with security element according to a variant when viewed at a second viewing angle; a schematic representation in plan view of a document of value with security element according to a further variant at a first viewing angle; a schematic representation in plan view of a value document with security element according to a further variant at a second viewing angle; a schematic representation of the manufacturing method of a value document according to a first variant; a schematic representation of the manufacturing method of a value document according to a second variant;

Supervision of schematic representations of layer structures of different distributed mirror surfaces; schematic sectional views of a section of a value document with different distributed mirror surfaces; and 12 is a schematic sectional view of a section of a security element with substructures on the relief.

1a, 1b show a sectional representation of a section of a value document 100 having a security element 101 which has a value document substrate 102, a representation 104 and distributed mirror surfaces 108, 108 '. The distributed mirror surfaces 108, 108 'are formed by relief elements 107, 107' of an embossed structure 106 and on the relief elements 107, 107 'arranged reflection region 109 (eg, metal layer). In addition to the reflection region 109, a non-reflective region 116 is arranged. The representation 104 is arranged between the second main surface HF _{2 of} the value document substrate 102 and the distributed mirror surfaces 108, 108 '. The distributed mirror surfaces 108, 108 'are arranged on or on the first main surface HFi of the value document substrate 102 and thus cover the representation 104. The representation 104 is not recognizable (viewing direction 110) or released (viewing direction 112), depending on the viewing angle and angle of the incident light ). When viewing the first main area HFi of the value document substrate 102 in reflected light from a first viewing direction 110, essentially only the incident light reflected at the distributed mirror areas 108 can be perceived by a viewer. In other words, the distributed mirror surfaces 108 prevent the perception of the representation 104, in particular by a strong reflection of light in the direction of the first viewing direction 110. It should be noted that the distributed mirror surfaces 108 'produce an analogous effect as the distributed mirror surfaces 108 when the viewer emerges from a corresponding viewing direction (not shown) on the first main surface HFi looks. When viewing the first main area HFi in incident light from a second viewing direction 112, the representation 104 is visible or recognizable to a viewer. For the recognizability of the representation 104, the viewing situation - characterized by the position and extent of the light source, the position of the observer and the orientation of the security element - plays a decisive role: If the light is reflected directly from the mirror surfaces 108 to the viewer, then the representation is 104 is not recognizable, because it is outshined by the mirror surfaces. In other viewing situations in which the mirror surfaces do not light up, however, the viewer can see the representation.

The distributed mirror surfaces 108, 108 ', as shown in Fig. Lb, the inclination angle γ, γ' have. Furthermore, the distributed mirror surfaces 108 and 108 'have different azimuth angles. In this example, the azimuth angles of the distributed mirror surface 108 and the distributed mirror surface 108 'differ by 180 °.

The relief or the embossed structure 106 spans a plane. The inclination angle γ, γ 'of the relief elements 107, 107' corresponds to the angle enclosed by the surface normal 114 of the plane and the surface normal 107N, 107N 'of the relief elements 107, 107'.

The relief elements 107, 107 'preferably have a structural width SW to 50 μιη. The relief elements 107, 107 'preferably have a structural height SH to 20 μπι on.

The reflection region 109 is metallic, for example. Alternatively, as a reflection region, a high refractive index material can also be used. The representation 104 is, for example, a representation prepared by printing technology. The representation 104 can be produced in particular by means of a printing technique or a combination of different printing techniques and / or color (s) or color systems. Preferably, the representation 104 may also comprise laser-generated elements. Further preferably, the representation 104 may also be made of a combination of translucent colors and an additional reflective layer. In this case, the translucent color layer or the translucent color layers are arranged between the embossed structure 106 or the distributed mirror surfaces and the additional reflection layer.

FIG. 1 c shows a perspective view of the value document 100, which comprises a representation 104, an embossed structure 106 and a multiplicity of reflection regions 109, as described above. In particular, FIG. 1c schematically shows the plane 118 which is spanned by the relief or relief layer 106. By tilting the value document 100 about a tilt axis, such as the tilt axes KAI or KA2, and / or a rotation about an axis of rotation, such as the rotation axis RA, a viewing angle or a viewing direction can be changed, so that the representation 104 (not shown) becomes visible or visible or suppressed or obscured.

FIG. 2 a shows a schematic representation in plan view of a value document 200 with a security element 214 when viewed at a first viewing angle. The security element 214 is constructed, for example, analogously to the security element 114 described in FIGS. 1 a and 1 b. In particular, the security element 214 comprises a representation and distributed mirror surfaces. The security element 214 is applied to the first major surface of a value document substrate 202.

When viewing the first main area under the first viewing angle, a viewer can not perceive the representation of the security element 214, since this is obscured by the reflection of the incident light at the distributed mirror surfaces.

By tilting the value document 200 about a tilt axis KA2, the viewing angle in reflected light can be changed to the first major surface of the value document substrate 202, so that the representation of the security element 214 becomes visible. This situation is shown schematically in FIG. 2b. The illustration according to FIG. 2b corresponds to a viewing of the first main surface of the value document substrate at a second viewing angle. As can be seen in Figure 2b, the representation 204, which represents the number "45" and a background, is visible to an observer A subsection of the section along the section line I-I of Figures 2a, b substantially corresponds to the sectional view according to Figure la.

3a and 3b show a schematic representation of a value document 300 having a security element 314 and a value document substrate 302. The security element 314 comprises a plurality of distributed mirror surfaces, which are arranged on / on the first main surface of the value document substrate 302 and cover a representation of the security element 314 , A plurality of the distributed mirror surfaces each have the same average orientation and thus forms a group. Another plurality of distributed mirror surfaces, which also have the same average orientation and inclination with each other, form a further group. According to the variant of Fig. 3a, 3b, the security element 314, the four areas Bl, B2, B3 and B4. Each of these areas comprises a plurality of distributed mirror surfaces having respective mean orientations and deviations therefrom. By rotating the value document 300 around a rotation axis (perpendicular to the plane of the drawing), a viewer can see or not see in turn the part of the representation or representation A, B, C and D, each distributed by a corresponding region Bl ... B4 Mirror surfaces covered with fixed orientations.

Figures 4a to 4h show schematically representations for the production method of a value document according to a first variant. FIG. 4 a shows a carrier substrate 402 and a stamping layer 400 applied thereto. In a (stamping) step, the stamping layer 400 is embossed, so that a relief

/ Embossed structure 404 is formed, as shown in Fig. 4b. In a further step, reflection regions 406 are then applied to relief elements of the relief 404, as shown in FIG. 4c. The relief elements having the reflection areas 406 form the distributed mirror surfaces. In this case, the reflection areas can preferably be applied by means of vapor deposition methods, for example vapor deposition methods. Alternatively, the metal layer is applied in the form of a metal particle dispersion. In this case, metal particles are present as so-called flakes in a binder. This metal particle dispersion or flakes can be applied, for example, by means of a printing process. The flakes are so thin that they conform to or follow the structure of the relief. In particular, reflection regions can be generated by patterning a (homogeneous) reflection layer by selective removal by means of an etching process. In this case, an etching can be partially applied to the reflection layer, for example, printed, which removes the reflection layer in these areas. Alternatively, the selective removal can take place by means of a so-called washing process. In this case, a so-called washing ink is applied in regions on the relief, for example printed. Only then is the reflective layer applied. The reflective layer is removed in the areas in which the wash ink was applied as soon as an aqueous solution comes into contact with the substance. With regard to the washing process, reference is made to document WO 99/13157 A1.

According to a further embodiment, as shown in FIG. 4d, the carrier substrate 402 may have been removed from the relief 404 in order to be able to apply the mirror surfaces without the carrier substrate 402 to the first main area HFi of a value document substrate 410. The first main area HFi of the value document substrate 410 has a representation 408 in this case. It should be noted here that auxiliary layers are applied at least temporarily on the relief side so that the carrier substrate 402 can be removed without the structure of the relief being impaired. After the relief 404 has been applied to the value document substrate 410, one or more of the auxiliary layers may be removed again. FIG. 4 e shows a value document substrate 410 on which the representation is applied and overlying a relief, as shown in FIG. 4 d, is applied.

Alternatively, as shown in FIG. 4f, the representation 408 can be applied to a side of the carrier substrate 402 opposite the relief 404. This layer structure may then be connected to a value document substrate 410 as shown in FIG. 4g. First of all, the illustration 408 and then the relief 404 is applied to the carrier substrate 402 is open. Furthermore, at least temporarily, auxiliary layers can be applied, for example in order to increase the stability of the structure during production. Furthermore, additional, not shown, layers such as primer layers, release layers, adhesive layers, etc., can be used.

According to another embodiment, as shown in FIG. 4h, a leveling layer 412 may be provided. The leveling layer 412 may be applied, for example, already at a manufacturing stage as shown in Fig. 4d. The leveling layer 412 protects the reflection layer.

In a structure as in FIG. 4h, the relief structures are thus molded into both the embossing layer and the leveling layer, and it ultimately does not matter for the optical effect which layer was embossed first and which layer levels the embossing of the other layer. Thus, the structure of Fig. 4h could also be achieved by first the layer 412 separately embossed and then laminated to the representation 408, wherein the relief structures then form into a liner between layer 412 and the representation 408, the laminating then paint So instead of the pre-history is.

In particular, Figures 4c and 4d represent an inventive

Layer structure. In particular, the relief elements are inclined relative to the surface normal of one of the contact surfaces 407a and 407b of the layer structure. FIGS. 5a to 5e show schematic illustrations of the method of producing a value document according to a second variant. 5a shows a carrier substrate 502 on which a stamping layer having an embossed structure / relief 500 is applied. The relief 500 has elevations 504a and depressions 504b. On the relief, a reflective layer 506 is applied, which has a low adhesion. The reflection layer 506 has the regions 506a and 506b. The regions 504a of the relief 500 correspond here to the regions 506a of the reflection layer 506. The regions 504b of the relief 500 in this case correspond to the regions 506b of the reflection layer 506. The reflection layer 506 is selectively removed in a next step, wherein the regions 506a of the reflection layer 506 be removed. Due to the low adhesion, the selective removal of the reflective layer is possible. This results in a structured reflection layer 506. The depressions 504b of the relief 500 and the regions 506b of the reflection layer 506 each form distributed mirror surfaces.

For example, the reflective layer 506 on the ridges 504a may be removed by separation winding. In this case, for example, a film can be laminated onto the reflection layer 506, which is in contact with the reflection layer 506 essentially only in the region of the elevations 504a. If the laminated film is removed again in a next step, the reflective layer 506 on the elevations 504a is removed together with the film. With regard to explanations on metal transfer or separation wraps, reference is made to the document DE 10 2012 018 774 AI. This process works ideally if the reflective layer is not adhered to the embossed structures.

In a further step, optionally a representation 508 can be applied to the carrier substrate 502. In this case, the representation 508 is applied to a surface of the support substrate 502 opposite to the surface having the relief 500.

The distributed mirror surfaces, as shown in FIG. 5c, can be separated from the carrier substrate 502 and applied via a representation 508 on or above a first main surface HFi of a value document substrate 510 (see FIG. 5e). Alternatively, a construction as shown in FIG. 5d may be applied to a first major surface HFi of a value document substrate 510. Furthermore, auxiliary layers can be applied at least temporarily in order, for example, to increase the stability of the structure during manufacture or application to a value-document substrate. Furthermore, additional layers, not shown, such as primer layers, release layers, adhesive layers, etc., can be used. FIGS. 6 to 8 schematically show a plan view of a layer structure comprising distributed mirror surfaces. Figures 6 and 7 show a patterned reflective layer defining reflective areas 602, 702 and non-reflective areas 604, 704 with the reflection areas as islands on the relief and each island surrounded by a non-reflective area 604, 704. The islands may have a width IW of less than or equal to 300 μιη. Adjacent islands may have a distance of less than or equal to 300 μπ \. Preferably, adjacent islands have a regular width IW and / or a regular distance RA. Fig. 6 shows a patterned reflective layer defining reflective regions 602 and non-reflective regions 604 arranged in a checkerboard pattern on a relief having a plurality of relief features. The reflection regions 602 and the non-reflective regions 604 have regular distances from one another, namely a grid spacing RA. FIG. 8 shows a patterned reflective layer defining reflective regions 802 and non-reflective regions 804, where the patterned reflective layer is a reflective layer having recesses 804 and each recess 804 is a non-reflective region.

The recesses may have a width AW of less than or equal to 300 μπι. Adjacent recesses may have a distance of less than or equal to 300 μιη. Preferably, adjacent recesses have a regular width AW and / or a regular distance RA.

9 shows a schematic sectional view of a detail of a value document with a layer structure 900. The layer structure 900 has distributed mirror surfaces which differ from the mirror surfaces illustrated in FIGS. 4 and 5. FIG. 10 also shows a schematic sectional representation of a section of a value document with a layer structure 1000. The layer structure 1000 has distributed mirror surfaces which differ from the mirror surfaces illustrated in FIGS. 4, 5 and 9. 11 shows a schematic sectional illustration of a section of a value document with a layer structure 1100, which shows a variant with elevations and depressions to FIGS. 5a-e.

12 shows a layer structure 1200, this layer structure is comparable to the layer structure 1100 according to FIG. 11. In contrast to the layer structure 1100, mirror surfaces 1202 have a substructure. Such a substructure may form a sub-wavelength grating and / or a hologram. Preferably, not all mirror surfaces of a layer structure have such substructures. Rather, some fixed mirror surfaces may have substructures distributed in such a way that a viewer may perceive information such as text, numbers, characters, and / or patterns.

For example, a layer structure may be designed in such a way that, when viewed in incident light at a first viewing angle of the observer, a lighting up of the mirror surfaces can perceive visible additional information. Alternatively or additionally, it may be provided that additional recesses are introduced into the mirror surfaces or the reflection regions (for example in the form of a value number, a symbol or lettering). Alternatively or additionally, the orientation of some relief elements can be chosen such that, under the first viewing angle, no reflection takes place at these relief elements (no illumination). In particular, mirror surfaces can be provided, which are at least region wise not inclined (inclination angle 0 °).

For example, mirror surfaces of a particular orientation may be provided, which together form characters such as letters, these mirror surfaces consisting of non-inclined mirror surfaces (surface normal parallel to the normal on the substrate). When viewed at a certain angle, the inclined mirror surfaces illuminate and outshine the image as well as the non-sloped mirror surfaces that form the character (letter). Therefore, in this viewing situation, neither the characters (letters) nor the representation can be seen. When the viewing angle is changed, for example, the representation becomes visible, while the characters (letters) can not be recognized. Only in a third viewing situation, when the non-inclined mirror surfaces that form the characters (letters) light up, they become recognizable against the background of the representation. In particular, the following production steps for layer structures (eg according to FIG. 4) can be carried out:

Applying the representation to the value document substrate;

Applying a stamping layer to the carrier substrate and introducing a relief (for example a sawtooth profile);

Applying e.g. Printing a wash ink on certain areas of the relief (structured application);

full-surface application of a reflective layer (e.g., metallization by vapor deposition);

selectively removing the reflective layer by washing so that the reflective layer is removed where the wash ink was previously printed;

optionally applying one or more layers of primer and / or protective and / or heat-sealing lacquer;

Gluing the security foil to the value document substrate above the display

Optional removal of the carrier film In particular, the following production steps can be carried out for layer structures (for example according to FIG.

Applying the representation to a carrier substrate;

Applying a stamping layer and applying a relief (e.g., sawtooth profile) on the opposite side of the support substrate;

- full-surface application of a reflective layer (e.g., metallization by vapor deposition);

Application, eg printing of a resist coating on certain areas of the relief (structured application); selectively removing the reflective layer by etching so that the reflective layer is removed where no resist was previously printed;

if necessary, removal of the remaining resist coating;

- Applying one or more layers with primer and / or protective lacquer on the side with the mirror surfaces

Applying heat sealing lacquer to the appearance;

In particular, the following fabrication steps may be performed for layered structures (e.g., as shown in Figures 5, 9, and 11):

Applying the image to a carrier substrate or a value document substrate;

Applying a Prägeschicht and introducing a relief with elevations and depressions;

non-adherent application of a reflective layer over the entire area (for example metallization by means of vapor deposition and use of a suitable embossing lacquer which allows detachment of the reflective layer)

Laminating a film of suitable thickness applied with an adhesive;

Separate winding while removing the metal layer of elevations;

It is advantageous here that the size, orientation and distribution of the mirror surfaces are exactly defined or matched to the embossed structure. In particular, the following production steps for layer structures can be carried out:

Applying the image to a carrier substrate or a value document substrate; Applying a Prägeschicht and introducing a relief with elevations and depressions;

Transfer of reflection areas on the relief by a reflective layer and a structured adhesive layer is disposed on a transfer belt and the structured adhesive layer is applied directly to the relief in a transfer step, wherein simultaneously with the structured adhesive layer and the reflective layer is transmitted in a structured manner. However, the reflection layer is transferred only where the structured adhesive layer is arranged on the relief. The transfer belt with the "remaining" reflection layer is preferably removed in a roll-to-roll process.

In particular, the following production steps for layer structures can be carried out:

- applying the representation on carrier substrate or value document substrate;

Applying a structured adhesive layer to the relief;

- Applying reflection areas on the relief by a reflective layer is disposed on a transfer belt and in a transfer step, the reflective layer is transferred in the areas on the relief, where the adhesive layer is present. The transfer belt with the "remaining" reflection layer is preferably transported off in a roll-to-roll process.

The described manufacturing steps can be varied in their timing. It is also possible to take steps from the various to combine written procedures. In this respect, the methods described here are merely examples.

In particular, the layer structure described herein may have additional layers, such as primer layers, release layers, adhesive layers, etc., which are not explicitly mentioned.

Finally, it should be mentioned once again that the above representations are schematic representations, that is, that size relationships, dimensions and contour curves do not necessarily correspond to reality. These representations are only intended to give a qualitative impression.

LIST OF REFERENCE NUMBERS

100, 200, 300 value document

102, 202, 302, 410, 510 value document substrate

104, 204, 408, 508 representation

107, 107 'relief element

107N, 107N 'surface normal of the relief element 108, 108' distributed mirror surface

109, 406, 506 Reflection areas

110 first viewing direction

112 second viewing direction

114, 404, 500 relief, embossed structure

214, 314 security element

400 pre-history

402, 502 carrier substrate

407a, 407b contact area

504a raises

504b wells

506a, 506b areas of the reflective layer

HFi first major area

HF ₂ second main surface

Y tilt angle

Bl, B2, B3, B4 Regions of distributed mirror surfaces SW Structure width

SH structural height

RA grid spacing

Claims

Patent claims

A layer structure for a security element, in particular a value document, comprising a multiplicity of distributed mirror surfaces for connection to a value document substrate, wherein

the distributed mirror surfaces are formed by reflection areas, which are applied on a relief with a plurality of relief elements, and the reflection areas cover between 10% to 90% of the surface of the relief or the distributed mirror surfaces by a high refractive, transparent or semitransparent reflection layer, the a relief having a plurality of relief elements is formed, wherein - when viewed in incident light at a first viewing angle reflected light at the distributed mirror surfaces, whereby the recognizability of the representation is suppressed, and

when viewed in incident light under a second viewing angle, the representation is recognizable.

2. Layer structure according to claim 1, wherein each relief element has an orientation which is defined by an inclination angle and an azimuth angle, and preferably each relief element has an inclination angle in the range of 0 ° to 60 °.

3. Layer structure according to claim 2, wherein some relief elements have a mean orientation corresponding to a predetermined angle of inclination and a fixed azimuth angle, and further relief elements have a deviation of up to about 15 ° from the specified angle of inclination and / or the specified azimuth angle.

4. The layer structure according to claim 1, wherein a plurality of relief elements having a first mean orientation or a deviation from this first mean orientation form a first group, and a plurality of relief elements having a second mean orientation or a deviation from this second middle orientation form a second group, and

the mean orientation of the first group and the second group differs, by at least 5 °, preferably by at least 10 °.

5. Layer structure according to one of claims 1 to 4, wherein a relief element has a structure width of up to 50 μπι; and or

has a structural height of less than or equal to 20 μιη; and / or the relief is formed by an embossed structure in a stamping layer; and / or a relief element has a substructure.

6. The layered structure of claim 1, wherein a patterned reflective layer defines the reflective areas and non-reflective areas, wherein the patterned reflective layer is a reflective layer with recesses and each recess is a non-reflective area, wherein the patterned reflective layer is preferably a patterned one metallic reflection layer is.

7. Layer structure according to claim 6, wherein the recesses have a width of less than or equal to 300 μπι; and or adjacent recesses have a distance of less than or equal to 300 μη, preferably, adjacent recesses have a regular width; and / or a regular distance.

A layered structure according to any one of claims 1 to 5, wherein a patterned reflective layer defines the reflective areas and non-reflective areas, wherein the reflective areas are present as islands on the relief and each island is surrounded by a non-reflective area, wherein the patterned reflective layer is preferably is a structured metallic reflection layer.

9. Layer structure according to claim 8, wherein the islands have a width of less than or equal to 300 μιη, and / or

neighboring islands have a distance of less than or equal to 300 μηα, preferably, adjacent islands have a regular width and / or a regular distance.

10. Layer structure according to one of claims 1 to 9, wherein the distributed mirror surfaces are formed such that a viewer can perceive no diffraction effects, and / or

the structuring of the structured reflection layer is below the resolution limit of the human eye so that a viewer can not distinguish the reflection areas and the non-reflective areas from each other.

11. Layer structure according to one of claims 1 to 10, wherein the distributed mirror surfaces are formed as depressions in the relief and / or are formed as elevations in the relief; and or

the layer structure comprises the representation; and or the representation is a representation produced by printing; and / or the representation comprises laser-generated elements; and or

the representation is based on translucent colors; and or

the representation is based on scattering colors; and or

the representation is based on a reflection layer; and or

the representation has recesses; and or

the representation comprises a foreground with a motif and an opaque background; and or

the representation comprises one or more translucent colors and a reflection layer equipped with or without recesses.

12. value document, in particular banknote, with

- a representation on one of the main surfaces, and

A layer structure according to at least one of claims 1 to 11, wherein the layer structure is applied to the first major surface of the value document substrate.

13. A method of making a value document comprising the steps of:

Applying a representation to one of the major surfaces;

Depositing a layer having a plurality of distributed mirror surfaces on the first major surface, which cover the representation, the distributed mirror surfaces being formed by reflection regions, which are applied on a relief having a plurality of relief elements, the relief inclined surfaces with respect to the first major surface, and the reflection ranges between 10% to 90% of the surface of the relief bede- or the distributed mirror surfaces are formed by a high refractive, transparent or semitransparent reflection layer, which is applied on a relief with a plurality of relief elements, wherein

when viewing the first main surface in incident light at a second viewing angle the representation is recognizable.

14. The method of claim 13, wherein the step of applying a plurality of inclined mirror surfaces comprises one or more of the following steps:

Producing a layer having a relief with a plurality of relief elements which is applied to the value document substrate;

Producing a structured reflection layer on the relief, preferably by means of metal transfer, printing, physical or chemical vapor deposition methods;

15. The method of claim 14, wherein the relief is created by creating an embossed pattern in a embossed layer.