DE102007043052A1 - Optically variable security element - Google Patents

Abstract

The invention relates to an optically variable security element (12) for securing valuables with an at least partially translucent, optically variable ink layer (26) showing a motif (28, 30) in the form of patterns, characters or a coding, wherein the color layer (26) contains first, optically variable effect pigments (32) and second, magnetically alignable effect pigments (34, 36) which are magnetically aligned in the form of the motif (28, 30) to be displayed.

Description

The The invention relates to an optically variable security element for Securing valuables. The invention relates Furthermore, a method and an apparatus for producing a Such security element as well as a security paper and a Data carrier with such a security element.

disk, like valuables or ID documents, but also other valuables, such as branded goods, are often hedged with security features provided a verification of the authenticity of the Data carrier allow and at the same time as protection against to serve unauthorized reproduction. The security elements can for example in the form of a security thread embedded in a banknote, a cover for a banknote with hole, an applied Security strip, a self-supporting transfer element or else in the form of a feature area printed directly on a document of value be educated.

A special role in the authentication of security play security elements, show the viewing angle dependent visual effects, as they do not reproduce even with the latest copiers can be. The security elements are included equipped with optically variable elements that underlie the viewer different viewing angles a different image impression mediate and, for example, depending on the viewing angle another Color or brightness impression and / or another graphic Show motive.

In In this context, it is known security elements with multi-layered Use thin-film elements whose color impression is for the viewer with the viewing angle changes, and when tilting the safety feature, for example, from green blue, blue to magenta or magenta to green replaced. The occurrence of such color changes in Tilting a security element is hereafter referred to as a color shift effect designated.

From the publication WO 02/073250 A2 Optically variable thin-film elements are known in whose layer structure at least one magnetic layer is integrated. The magnetic properties of these optically variable thin-film elements can then be used as an additional authenticity mark.

In the publication EP 1 780 040 A2 describes a security element in which in a partial area magnetically oriented pigment particles are present, which produce a kinematic visual effect. The magnetically oriented pigment particles may in particular also have optically variable properties.

outgoing It is the object of the invention to provide a security element of the type mentioned above to improve and in particular a security element with an attractive visual appearance and high counterfeit security intelligent combination with other, in particular underlying Security features allowed.

These Task is characterized by the security element with the characteristics of Main claim solved. A method and a device for producing such a security element, a security paper and a data carrier with such a security element are given in the independent claims. further developments The invention is the subject of the dependent claims.

According to the Invention has a generic security element an at least partially translucent, optically variable ink layer on which a motif in the form of patterns, characters or a coding shows, and in which the color layer of the security element first, optically variable effect pigments and second, magnetically alignable Contains effect pigments that are magnetically in the form of the displayed Motive are aligned.

One such security element offers a combination of attractive visual Effects, namely on the one hand the optically variable effect the first effect pigments and the other by the magnetic Alignment of the second effect pigments generated motif, which a pronounced three-dimensional appearance having. By their at least partially present translucency In addition, the optically variable color layer with other underlying security features, such as a information-carrying printing layer or a see-through area combined become.

in the As used herein, "translucent" means translucent in the sense of a certain or complete translucency and thus also includes transparency. A translucent Layer allows the objects behind or below it to perceive, even if through the translucent layer the brightness reduces the objects and / or changes the color of the objects can be. Is the light transmission of a layer against it so small that the objects behind or behind them are not are more recognizable, it is no longer translucent, but will referred to as opaque or opaque.

The Invention is based now on the idea of a color layer with two different effect pigments with different specifics To use properties. The first effect pigments are included optically variable while the second effect pigments are magnetic are alignable. Essentially only the latter, but not the first Effect pigments become aligned through an external magnetic field magnetically oriented in the form of the motif to be displayed.

These Decoupling of the optically variable and the magnetic properties allows a cost-effective production, since effect pigments, combining optically variable and magnetic properties, a higher production cost and thus a require higher costs. In addition, such Effect pigments typically opaque, leaving an intelligent Combination with other printing processes or inks only very much restricted is possible. In addition, the required Layer structure of the pigments and the associated selective Reflection stringent requirements for the possible layer thicknesses of the magnetic material. This leads to limitations in the magnetic properties, in particular the remanence and coercive field strength, which is a machine-readable generation Make security elements difficult.

In a preferred embodiment of the invention includes the Optically variable color coat a pigment mixture with the first and second effect pigments. Alternatively, the optically variable color layer also a pure magnetic layer with the second effect pigments and a pure color layer arranged above the pure magnetic layer containing the first effect pigments.

The first effect pigments are advantageously based on liquid crystalline polymers prepared pigments or so-called pearlescent pigments, such as those sold by the company Merck KGaA under the designation Iriodin ^® or Colorcrypt silver-white, gold luster or metal luster pigments. Both pigments based on liquid-crystalline material and pearlescent pigments are translucent on their own. In other likewise advantageous embodiments of the invention, the first effect pigments are formed by interference layer pigments. Such interference layer pigments typically have a thin-film structure which expediently contains at least one reflection layer, one absorber layer and a dielectric spacer layer arranged between the reflection layer and the absorber layer. Interfacial layer pigments can be translucent per se, although opaque interference layer pigments are also known.

The second effect pigments are preferably formed on the basis of high-purity iron powder and can be prepared, for example, from reducing-treated carbonyl iron powder. Advantageous platelet-shaped iron pigments can in particular the document EP 1 251 152 B1 are taken from the disclosure of the preparation and properties of such pigments in the present description.

In an advantageous embodiment of the invention are the second Effect pigments hard magnetic and thus allow in a particularly reliable manner a mechanical magnetic readout of the depicted motif. Preferably, the second effect pigments are in the form of a machine-readable magnetic coding, such as a barcode aligned. Of course, the second Effect pigments also be fundamentally soft magnetic, although soft magnetic effect pigments for the ma chine magnetic readings are not as well suited as hard magnetic ones Pigments.

Prefers the second effect pigments are non-spherical, for example needle-shaped. Particular preference is given to effect pigments, which have a platelet shape. In addition, the largest Diameter of a non-spherical pigment as a length or size of the pigment, while the thickness of the pigment is referred to as pigment thickness. In general is the thickness of the pigments with the smallest diameter of the pigment be identical. In addition, the terms length, Size and largest diameter of the pigment and thickness and smallest diameter of the pigment used synonymously. The ratio of the largest to the smallest diameter, so the diameter-to-thickness ratio which is non-spherical second effect pigments preferably more than 5: 1, preferably more than 10: 1. Especially preferred this ratio is between 40: 1 and 400: 1. The biggest Diameter, that is the length of the non-spherical second effect pigments is advantageously more than 2 μm, preferably more than 5 microns, more preferably more than 10 microns and most preferably more than 15 microns.

The Use of magnetically orientable effect pigments in the micrometer range and in particular in said size range on the one hand the advantage that the particle concentration compared can be kept lower with nanoparticles. About that In addition, these pigments are due to the cheaper Diameter to thickness ratio without external forces better parallel to the layer surface.

Platelet-shaped effect pigments, in particular in the preferred size range and in the before The preferred diameter-to-thickness range can be oriented as desired by an external magnetic field relative to the layer plane. They then, like the slats of a blind, depending on the orientation of the underlying layers either largely free (approximately vertical orientation relative to the layer plane) or block it partially (oblique orientation relative to the layer plane) or completely (substantially horizontal orientation relative to the layer plane ). With high diameter-to-thickness ratios, high contrasts between translucent and opaque layer areas can be set.

To A preferred embodiment of the invention are the second effect pigments platelet-shaped and are in first Subareas substantially perpendicular to the plane of the color layer aligned to form translucent portions of the color layer. Alternatively or additionally, platelet-shaped second effect pigments in the second partial areas substantially parallel be aligned to the layer of color layer to opaque portions to form the color layer.

The optically variable ink layer is preferably by a screen printing layer, formed in some embodiments by a gravure printing layer. It can be in addition to all mentioned embodiments be blind imprinted, especially for reinforcement the 3D effect of the magnetically oriented effect pigments.

to Fixation of the magnetically oriented motif is the color layer with the pigment mixture, preferably based on a UV-curing color system formed using pure UV systems, UV / water based systems or also UV / solvent-based systems come into consideration. In addition to the first and second effect pigments, the color layer also other pigments, in particular isotropic pigments and / or soft magnetic Contain pigments. Of course you can the other pigments or in general further additives all have visually and / or machine-detectable properties, the visual impression of the invention Do not or only slightly affect security elements.

In An advantageous embodiment is the optically variable ink layer on a banknote paper or on a colored background layer applied. As substrate material for the banknote paper comes any type of paper, in particular cotton vellum paper. Of course, paper can also be used, which contains a proportion x polymeric material in the range of 0 <x <100 wt .-%.

Farther it is conceivable in principle, if present not preferred that the substrate material of the banknote or whole generally a data carrier, a plastic film, for. B. a polyester film is. The film may also be monoaxial or biaxial be stretched. The stretching of the film leads among other things that it receives polarizing properties, the can be used as another security feature.

expedient it may also be when the substrate material of the banknote paper is a multilayer composite comprising at least one layer Paper or a paper-like material. Such a composite characterized by an extraordinarily large Stability out, indicating the durability of the paper or data carrier is of great advantage.

Conceivable But is also, as a substrate material, a multi-layered, paper-free Use composite material. These materials are also present not preferred but may be in certain climatic regions the earth can be used with advantage.

All Materials used as substrate material may include additives which serve as authenticity features. It is first Line of luminescent substances to think in the visible wavelength range are preferably transparent and in the non-visible wavelength range by a suitable tool, for. B. a UV or IR radiation emitting radiation source, can be excited to a visible or at least with aids detectable To produce luminescence. Also other security features can be used with advantage, provided they consider the consideration of the invention Security elements do not or at least not significantly affect.

Underground layers with dark colors usually lead to a special high brilliance of the optically variable effects. As a substrate comes but also a transparent or translucent film in question. In In this case, the security element can advantageously be in or above a window area or a through opening of a value document be used as a see-through security element. The foil can as a patch covering a partial area of the substrate or as a one over the entire length or Width of the security paper or value document extending strip be educated. As materials for the film come primarily the plastics PET (polyethylene terephthalate), PBT (Polybutylene terephthalate), PEN (polyethylene naphthalate), PP (polypropene), PA (polyamide), PE (polyethylene) into consideration. The film can also monoaxially or biaxially stretched.

In some embodiments, the opening is already in the production of the for the banknote used security paper and has a fibrous, irregular edge. Such an edge is characteristic of openings already made during sheet formation and can not be subsequently produced. Details of the production of the fibrous, irregular edge can the WO 03/054297 A2 be removed. In that regard, the disclosure of the WO 03/054297 A2 included in the present application. In other embodiments, the opening is produced only after papermaking by punching or cutting, for example by laser beam cutting.

The Optically variable ink layer can in a further development of the invention on an informative underground, in particular applied to a screen printing layer or a gravure printing layer be. As the information in the translucent areas of the paint layer recognizable, in the opaque areas, however, is hidden, can paint layer and background layer to produce another authenticity feature interact, as explained in more detail below.

The Substrate layer can also thermochromic properties with advantage have an interactively influenceable security element to accomplish. Such a thermochromic background layer can in particular be designed so that when activated by temperature increase the optically variable effect of the first effect pigments for the Viewer disappears.

• – auf ein Substrat eine zumindest bereichsweise transluzente, optisch variable Farbschicht aufgebracht wird, die erste, optisch variable Effektpigmente und zweite, magnetisch ausrichtbare Effektpigmente enthält, und
• – die zweiten Effektpigmente durch ein externes Magnetfeld ausgerichtet werden, um ein Motiv in Form von Mustern, Zeichen oder einer Codierung zu bilden.

The invention also encompasses a method for producing an optically variable security element for securing valuables, in which

• - On a substrate, an at least partially translucent, optically variable ink layer is applied, the first, optically variable effect pigments and second, magnetically alignable effect pigments contains, and
• - The second effect pigments are aligned by an external magnetic field to form a motif in the form of patterns, characters or a coding.

Prefers In the process, the first and second effect pigments become a pigment mixture mixed and co-printed, preferably in Siebdruck- or in intaglio printing.

alternative can on the substrate first a pure magnetic layer printed with the second effect pigments, and over the pure magnetic layer then a pure color layer with the first Effect pigments are printed. Also here is the pure magnetic layer and / or the pure color layer preferably by screen printing or in Intaglio printing printed.

The The motif produced by the magnetic alignment becomes advantageous Design by UV curing of the ink layer or the pure magnetic layer permanently fixed.

The The invention further comprises a security paper for the Production of value documents or the like and a data carrier, in particular a value document, such as a banknote, a passport, a Certificate, ID card or the like. The security paper or the data carrier according to the invention with equipped a security element of the type described. The Security element can, especially if it is on a transparent or translucent substrate, also in or over a window area or a through opening of the Security paper or the disk can be arranged.

object The invention is further an apparatus for implementation the described manufacturing method, the means for applying the optically variable ink layer on a substrate and means for magnetic Align the second effect pigments, wherein the means for magnetic alignment, preferably by an arrangement of Permanent or electromagnet are formed.

With The advantage here is the optically variable ink layer with a suitable Process applied to the intended substrate and the second effect pigments then aligned, z. B. by a magnetic pressure cylinder. Subsequently, the optically variable ink layer is complete the motif formed by the orientation of the second effect pigments Permanently fixed, what z. B. by the aforementioned UV curing can be done.

In an expedient embodiment are the means formed for magnetic alignment by a magnetic sieve, so that the second effect pigments already during the printing of the color layer or the pure magnetic layer in screen printing magnetically aligned are.

Become the second effect pigments or the color layer in intaglio printing Applied, so can the means for magnetic alignment also be formed by a magnetic throat plate, so that the second Effect pigments already when printing the ink layer or the pure magnetic layer in intaglio printing are magnetically aligned.

Other embodiments and advantages of the invention will be explained below with reference to the figures, in the representation of a Maß bar and proportions faithful reproduction was omitted in order to increase the clarity.

It demonstrate:

1 a schematic representation of a banknote with a security element according to the invention,

2 the banknote of 1 in the area of the security element in cross section,

3 an interactively influenceable security element according to another embodiment of the invention in cross-section,

4 a security element according to a further embodiment of the invention in cross-section,

5 a banknote having a see-through security element according to the invention, which is arranged over a continuous opening, and

6 a security element according to a further embodiment of the invention with an alternative design of the optically variable ink layer.

The invention will now be explained using the example of a banknote. 1 shows a schematic representation of a banknote 10 that with an in 2 shown in cross-section security element according to the invention 12 is provided.

With reference to the representation of 2 is on the banknote paper 20 in the area of the security element 12 a print layer 22 applied any information, such as a line pattern 24 , an alphanumeric string, a logo or the like. The print layer 22 For example, by screen printing or intaglio printing on the banknote paper 20 be upset.

About the information-bearing print layer 22 is an optically variable ink layer in the screen printing process 26 imprinted with a color shift effect, in which the color impression of the layer 26 for the viewer when tilting the security element 12 z. B. changes from green when viewed perpendicularly to blue when viewed obliquely. It is also conceivable a color change of z. B. coppery green or from gold to green.

Next contains the color layer 26 a motif that in the embodiment of 2 for illustration in the form of a simple stripe pattern 28 . 30 is executed. As explained in more detail below, this motif indicates 28 . 30 due to its formation by the different orientation of platelet-shaped pigments 34 . 36 for the viewer a pronounced 3D effect.

In the field of stripes 30 is the color layer 26 doing translucent, so that in the sub-areas 30 the information 24 through the color layer 26 can be seen through. In the field of stripes 28 is the color layer 26 on the other hand opaque, there is the information 24 the print layer 22 covered.

To this combination of a motif with 3D effect, color shift effect and partial visibility of the background printing layer 22 to produce the color layer 26 using a pigment mixture of first effect pigments 32 and second effect pigments 34 . 36 printed.

At the first effect pigments 32 they are optically variable pigments, for example interference layer pigments with a thin-film structure comprising a reflection layer, an absorber layer and a dielectric spacer layer arranged between the reflection layer and the absorber layer. Also, on the basis of liquid-crystalline polymers produced iridescent pigments or pearlescent pigments, as are marketed, for example from Merck KGaA under the designation Iriodin ^® or Colorcrypt come first-effect pigments 32 into consideration.

In addition to these optically variable first effect pigments 32 contains the pigment mixture as a second effect pigments magnetically alignable, platelet-shaped iron pigments 34 . 36 , which are made in the embodiment of reducing treated carbonyl iron powder. Such platelet-shaped iron pigments can be produced with a high ratio of platelet diameter to platelet thickness, wherein the (largest) platelet diameter is preferably between 6 .mu.m and 60 .mu.m and the platelet thickness in particular between 40 nm and 250 nm. Details of the preparation and properties of such platelet-shaped iron pigments can be found in the document EP 1 251 152 B1 are removed, the disclosure of which is included in the present description.

For the production of the color layer 26 became the first and second effect pigments 32 . 34 . 36 mixed and jointly screen printed. Then, the magnetically alignable second effect pigments were partially aligned by an external magnetic field. The iron pigments 34 . 36 orient themselves with the platelet expansion along the magnetic field lines, so that the iron pigments 36 in those areas 30 in which the magnetic field lines during the alignment step are substantially perpendicular to the substrate plane, substantially perpendicular to the plane of the color layer be judged, as in 2 shown. In those areas 28 in which the magnetic field lines run essentially parallel to the substrate plane, a corresponding orientation of the iron pigments is obtained which lies essentially in the plane of the ink layer 34 ,

The platy iron pigments 34 . 36 According to the invention in the form of a desired motif, in the embodiment in the form of the stripe motif 28 . 30 aligned. For the human eye, the motifs created in this way appear with an effective, three-dimensional appearance, which in the context of this description is also referred to as a 3D effect or 3D impression of the motif.

In embodiment of the 2 For the sake of simplicity, only two orientations, namely perpendicular (90 °, pigments 36 ) or parallel (0 °, pigments 34 ) to the substrate plane. It is understood, however, that any angle α between the iron pigment platelets and the layer plane can be adjusted by appropriate orientation of the magnetic field lines. In particular, it is also possible to generate continuous, spatially slowly varying transitions in the orientation of the iron pigments.

The non-magnetic first effect pigments 32 are not or hardly influenced by the external magnetic field during the alignment step, their orientation is therefore in the subregions 28 and 30 equal.

After the magnetic alignment of the second effect pigments 34 . 36 becomes the color layer 26 dried. In order to be able to fix the magnetically generated motif permanently, in particular UV-curing color systems are used, pure UV systems, UV / water-based systems or even UV / solvent-based systems being considered.

Like also in 2 to recognize, the aligned effect pigments act 34 . 36 due to its platelike shape like the slats of a blind, which can reveal the view of the underlying layers or block completely or partially. In the fields of 28 in which the iron pigments 34 Aligned substantially parallel to the substrate plane, they limit the view of the underlying printing layer 22 so strong that the color layer 26 appears opaque in this area. It should be remembered that in practice the opaque effect of the pigments 34 Of course, it is caused by a variety of pigments, which are the few pigments 34 the schematic representation of 2 exceeds many times. On the other hand give the iron pigments 36 in the fields of 30 in which they are oriented substantially perpendicular to the substrate plane, the view of the print layer 22 free.

Due to the relatively high ratio of platelet diameter to platelet thickness, a high contrast between opaque partial areas can be achieved 28 and translucent subregions 30 produce. It is understood that a continuous transition of the platelet orientation also provides a smooth, continuous transition between translucent and opaque regions of the color layer 26 can be generated.

The color shift effect of the first effect pigments not substantially influenced by the external magnetic field 32 remains in both areas 28 . 30 visible, noticeable. Due to the superposition with the metallic luster of the second effect pigments oriented parallel to the substrate surface 34 he is, however, in the subarea 28 usually significantly weaker than in the partial area 30 , The brilliance of the color shift effect in the subarea 30 also depends on the design of the background layer, whereby a particularly high brilliance is achieved when using dark colors.

The embodiment of 3 shows a security element 40 , which allows an interactive influence on the visual appearance. This is a substrate 42 with a print 43 , in particular offset printing, in the form of patterns and / or characters 45 Mistake. On the imprint 43 is a thermochromic background layer 44 applied, for example by screen printing or intaglio printing. On this thermochromic layer 44 is then an optically variable ink layer 26 with motive, as related to 2 described, printed and magnetically aligned.

The thermochromic layer 44 is designed so that the color shift effect of the paint layer 26 upon activation of the thermochromic layer 44 for the viewer disappears and only the coarse structure of the aligned magnetic pigments 34 . 36 is visible. Change the thermochromic layer 44 For example, when activated by temperature increase their color of black (or generally a dark appearance) on white (or generally a bright appearance), the brilliance of the color shift effect is significantly reduced during activation, to a degree in which the optical variable effect of the first effect pigments 32 completely disappears for the viewer. At the same time is due to the very light layer 44 the imprint 43 to recognize for the viewer. When cooled, the color of the thermochromic layer changes 44 back to black or to the original dark appearance, and the color shift effect of the color layer 26 reappears. At the same time the dark layer hides 44 then again the under her arranged imprint 43 ,

In this way, 3D information can be deleted interactively by increasing the temperature or reduced to a two-dimensional information. Furthermore, the thermochromic layer acts 44 almost as an interactive switch with which the view of the print 43 or the information 45 can be released to the viewer. The described embodiment therefore has a great recognition value for the viewer and generally a very high security against counterfeiting.

The thermochromic layer 44 can also be formed over the entire surface or with information, such. B. in the form of patterns and / or characters, be provided. It can also have a mixture of different thermochromic colors with different activation temperatures, so that a cascade of changing optically variable effects arises when the temperature increases.

As a further embodiment of the invention shows 4 a security element 50 in which on a substrate 52 a background layer 54 is applied with an image information. Above the background layer 54 is an optically variable ink layer in the screen printing process 56 with a pigment mixture 58 . 60 printed, its first effect pigments 58 based on cholesteric liquid-crystalline polymers. These translucent optically variable effect pigments 58 appear in a vertical view z. Green and tilting blue. Of course, a color change from copper to green or from gold to green can be realized.

The second effect pigments 60 are formed by platelet-shaped iron pigments, which in the embodiment have a mean platelet diameter of 20 microns to 30 microns and a thickness of several tens to several hundred nanometers (nm). Will these second effect pigments 60 through an external point-shaped magnet 66 aligned, so results in a rotationally symmetric orientation pattern, as in 4 is shown schematically in cross section. For clarity, the second effect pigments are 60 in 4 with short strokes and the first effect pigments 58 represented as circular disks, although the latter may also be formed non-spherical, for example in the form of needles or platelets. Because the first effect pigments 58 however, are virtually unaffected by the external magnetic field, their orientation is over the entire area of the printed ink layer 56 essentially homogeneous.

After fixing the magnetic alignment of the second effect pigments 60 arises with the color shift effect of the first effect pigments 58 Combined, ring-shaped 3D motif with smooth continuous transitions. In a central area 62 , in which the second effect pigments 60 are oriented substantially perpendicular to the substrate plane, the color layer 56 when viewed vertically, translucent and the image information of the background layer 54 is for the viewer 64 visible, noticeable. Outside the central area 62 are the second effect pigments 60 increasingly tilted from the vertical, leaving the paint layer 56 In the manner of a closing Venetian blind appears increasingly opaque until the image information for the viewer 64 no longer recognizable.

As in 4 can also be seen, results in oblique viewing of the security element, a slightly shifted area 62 ' , in which the second effect pigments 60 for the viewer 64 ' are vertically oriented and the color layer 56 so that translucent appears. Accordingly, for the viewer 64 ' a slightly shifted section of the image information of the background layer 54 recognizable while the image information is out of range 62 ' is increasingly obscured.

When tilting the security element 50 Therefore, in each case a slightly different area of the image information is recognizable, so that the image information for the viewer "wegzuschwimmen" seems. This movement effect is of course with the already described 3D effect of the subject and the color shift effect of the first effect pigments 58 combined.

Instead of the example described simple ring structure, as using a point magnet can be generated by suitable Of course, magnetic alignment is also essential Create more complex motifs.

The optically variable ink layer with the pigment mixture may be printed not only on an opaque or substantially opaque substrate but also on a transparent or translucent film. As in 5 As shown, such a film may have the optically variable ink layer over a window area or through opening 72 a banknote 70 be arranged and a see-through security element 74 form.

In review, only the magnetic orientation of the second effect pigments can be seen, which in 5 exemplified by a ring structure 76 is indicated. The color-shift effect of the first effect pigments is virtually invisible on account of the light background when viewed through. If you put the banknote 70 on a dark background, so in addition to the 3D effect of the mag nicely oriented theme 76 Also, the color shift effect of the first effect pigments in appearance.

Such a dark background can also be on the banknote 70 be provided by yourself. For example, a dark printing area can be arranged on the banknote such that the see-through security element 74 by folding the note on the dark print area comes to rest. For further authenticity assurance, the printing area may contain additional information, from which only the portion lying in the translucent area is visible after folding the banknote.

6 shows a security element according to the invention 80 with an alternative design of the optically variable ink layer 84 , In this embodiment, an arbitrary substrate is used 82 first a screen printing ink with magnetically orientable iron pigments 86 imprinted and the pigments 86 aligned according to the desired motif. Subsequently, over this pure magnetic layer 88 a pure color layer 90 with optically variable effect pigments 92 printed. Due to the magnetic orientation of the iron pigments 86 In some areas, the print pattern appears black, while in non-oriented areas, the metallic impression dominates. Especially when using effect pigments 92 , whose visual impression strongly depends on the background color, show in the overprint interesting optical effects.

at all described embodiments, the optical variable color layer also blind embossed in intaglio especially to enhance the 3D optical impression. The platelet-shaped iron pigments preferably used are hard magnetic, so that their orientation pattern as a machine-readable authenticity mark can be used.

Further result from the anisotropic geometry of the iron platelets and a partially different orientation anisotropic magnetic properties of the color layer. Let that way by applying a motivating magnetic field in a homogeneous Applied color layer areas with different magnetic properties generate, which can also be read by machine. It is understood that the first and second effect pigments too with further pigments, in particular with isotropic pigments and / or soft magnetic pigments can be combined, the essentially no modulation of the magnetic Allow properties of the color layer.

At the Screen printing can be the orientation of the magnetically alignable Effect pigments can also be made by using magnetic sieves. Intaglio printing is used for this purpose magnetic throat plates into consideration. As already mentioned, Furthermore, the magnetic alignment of the effect pigments is particularly simple Way after applying the optically variable ink layer through a suitable magnetic field possible.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 02/073250 A2 [0005]
• - EP 1780040 A2 [0006]
• - EP 1251152 B1 [0016, 0057]
• WO 03/054297 A2 [0030, 0030]

Claims (47)

Optically variable security element for protection of valuables with an at least partially translucent, optically variable color layer that forms a motif of patterns, characters or a coding in which the color layer first, optically variable effect pigments and second, magnetically alignable Contains effect pigments that are magnetically in the form of the displayed Motive are aligned. Security element according to claim 1, characterized in that that the optically variable ink layer is a pigment mixture with the contains first and second effect pigments. Security element according to claim 1, characterized in that that the optically variable color layer with a pure magnetic layer with the second effect pigments and one above the pure magnetic layer arranged pure color layer containing the first effect pigments. Security element according to at least one of the claims 1 to 3, characterized in that the first effect pigments by based on liquid crystalline polymers Pigments are formed. Security element according to at least one of the claims 1 to 3, characterized in that the first effect pigments are formed by pearlescent pigments. Security element according to at least one of the claims 1 to 3, characterized in that the first effect pigments are formed by interference layer pigments. Security element according to claim 6, characterized the interference layer pigments comprise at least one reflection layer, an absorber layer and one between the reflective layer and the Absorber layer arranged dielectric spacer layer included. Security element according to at least one of the claims 1 to 7, characterized in that the second effect pigments are formed on the basis of high-purity iron powder. Security element according to at least one of the claims 1 to 8, characterized in that the second effect pigments are hard magnetic. Security element according to at least one of the claims 1 to 9, characterized in that the second effect pigments non-spherical, in particular platelet-shaped are formed. Security element according to claim 10, characterized in that that the ratio of the largest to the smallest Diameter (diameter-to-thickness ratio) of the non-spherical second effect pigments are more than 5: 1, preferably more than 10: 1, and more preferably between 40: 1 and 400: 1. Security element according to claim 10 or 11, characterized characterized in that the largest diameter of the non-spherical second effect pigments more than 2 μm, preferably more than 5 microns, more preferably more than 10 microns and most preferably more than 15 microns. Security element according to at least one of the claims 1 to 12, characterized in that the second effect pigments are formed platelet-shaped and in the first Subareas substantially perpendicular to the plane of the color layer are aligned to translucent portions of the color layer to build. Security element according to at least one of the claims 1 to 13, characterized in that the second effect pigments are formed platelet-shaped and in the second Partial areas substantially parallel to the layer of the color layer are aligned to form opaque portions of the color layer. Security element according to at least one of the claims 1 to 14, characterized in that the second effect pigments aligned in the form of a machine-readable magnetic coding are. Security element according to at least one of the claims 1 to 15, characterized in that the optically variable ink layer is formed by a screen printing layer. Security element according to at least one of the claims 1 to 15, characterized in that the optically variable ink layer is formed by a gravure printing layer. Security element according to at least one of the claims 1 to 17, characterized in that the optically variable color layer is blindly stamped. Security element according to at least one of the claims 1 to 18, characterized in that the color layer with the pigment mixture is formed on the basis of a UV-curing color system. Security element after at least one of claims 1 to 19, characterized in that the color layer in addition to the first and second effect pigments further pigments, in particular isotropic pigments and / or soft magnetic pigments. Security element according to at least one of the claims 1 to 20, characterized in that the optically variable ink layer on a banknote paper or on a colored background layer, preferably a background layer with a dark color applied is. Security element according to at least one of the claims 1 to 20, characterized in that the optically variable ink layer is applied on a transparent or translucent film. Security element according to at least one of the claims 1 to 22, characterized in that the optically variable ink layer on an informative background, especially one Screen printing layer or a gravure printing layer is applied. Security element according to at least one of the claims 1 to 23, characterized in that the optically variable ink layer is applied on a thermochromic background layer. Security element according to claim 24, characterized that the thermochromic background layer is designed so that at their activation tion by increasing the temperature of the optical variable effect of the first effect pigments for the viewer disappears. Security element according to claim 24 or 25, characterized characterized in that the thermochromic background layer over an imprint, in particular an imprint in the form of patterns and / or characters. Method for producing an optically variable Security elements for securing valuables, in which On a substrate an at least partially translucent, optically variable ink layer is applied, the first, optical variable effect pigments and second magnetically orientable effect pigments contains, and - the second effect pigments be aligned by an external magnetic field to a subject in the form of patterns, characters or an encoding. Method according to Claim 27, characterized that the first and second effect pigments to a pigment mixture mixed and printed together. Method according to Claim 28, characterized that the pigment mixture is printed by screen printing or intaglio printing becomes. Method according to Claim 27, characterized that on the substrate initially a pure magnetic layer is printed with the second Effektpigmen th, and about the pure magnetic layer is a pure color layer with the first effect pigments is printed. Method according to claim 30, characterized that the pure magnetic layer and / or the pure color layer in screen printing or is printed in intaglio printing. Method according to at least one of the claims 27 to 31, characterized in that the magnetically generated Motive by UV curing of the color layer or the pure magnetic layer is fixed. Method according to at least one of the claims 27 to 32, characterized in that the second effect pigments are formed platelet-shaped and in the first Subareas substantially perpendicular to the plane of the color layer be aligned to translucent portions of the color layer to build. Method according to at least one of the claims 27 to 33, characterized in that the second effect pigments are formed platelet-shaped and in the second Partial areas substantially parallel to the layer of the color layer be aligned to form opaque portions of the color layer. Method according to at least one of the claims 27 to 34, characterized in that the second effect pigments aligned in the form of a machine-readable magnetic coding become. Method according to at least one of the claims 27 to 35, characterized in that the optically variable ink layer is blind embossed in intaglio. Security paper with a security element after at least one of claims 1 to 26 or one according to at least one of claims 27 to 36 produced Safety element. Security paper according to claim 37, characterized that the security element in or above a pane or a continuous opening of the security paper is arranged. Disk with a security element according to at least one of claims 1 to 36 or a security paper according to claim 37 or 38. A data carrier according to claim 39, characterized that the security element in or above a pane or a through opening of the data carrier is arranged. A data carrier according to claim 39 or 40, characterized in that the data carrier is a banknote Value document, a passport, a certificate or an identity card. Use of a security element after one of claims 1 to 36, a security paper according to claim 37 or 38 or a data carrier according to one of the claims 39 to 41 for the protection of objects of any kind. Apparatus for carrying out the method according to one of claims 27 to 36 with means for applying the optically variable ink layer on a substrate and with agents for magnetic alignment of the second effect pigments. Device according to claim 43, characterized in that that the means for magnetic alignment by an arrangement are formed by permanent magnets or electromagnets. Device according to claim 43 or 44, characterized that the means for magnetic alignment by a magnetic Printing cylinders are formed, so that the second effect pigments only after the printing of the color layer or the pure magnetic layer are magnetically alignable. Device according to claim 43 or 44, characterized that the means for magnetic alignment by a magnetic Sieve are formed, so that the second effect pigments in printing the color layer or the pure magnetic layer in screen printing magnetic are alignable. Device according to claim 43 or 44, characterized that the means for magnetic alignment by a magnetic Throat plate are formed, so that the second effect pigments when Imprinting the color layer or the pure magnetic layer in intaglio printing are magnetically alignable.