EP4342682A1 - Security element comprising a machine-readable code and method for producing same - Google Patents

Abstract

A security element 10 is proposed, preferably in the form of a security strip 10c, security thread 10a, 10b or security patch 10d, which includes a machine-readable code and an optically variable security feature which has a visual appearance dependent on the viewing angle. The machine-readable code is a magnetic coding that is produced by printing technology using at least one opaque magnetic printing ink M1, M2, M3 containing magnetic pigments, which is incorporated or applied in at least one defined code area C1, C2, C3 in such a way that the visual appearance of the optically variable security feature is at least partially determined by the at least one inserted or applied magnetic printing ink M1, M2, M3. The optically variable security feature comprises a micro-optical microlens arrangement 11, which covers the at least one code area C1, C2, C3, in which the at least one magnetic printing ink M1, M2, M3 is incorporated or applied.

Description

The present invention relates to a security element, preferably in the form of a film strip, film thread or film patch, with a machine-readable code and a method for producing such a security element.

To protect against counterfeiting, documents of value are typically provided with security elements that implement security features with visually and/or machine-verifiable properties, which can be used to check the authenticity of the document of value. For this purpose, various security features are known from the prior art, which differ in particular with regard to the technical means with which the security feature can be detected or verified.

Of particular importance are visual security features with optically variable properties, ie the appearance of the visual security feature varies depending on the viewing angle. When the viewing angle is continuously changed, a tilting and/or movement effect in particular can be visualized. Such security features are considered to be very counterfeit-proof, since the optically variable effect, which depends on the viewing angle, generally cannot be detected with sufficient precision by a counterfeiter to imitate it. In addition, such optically variable effects cannot be created through regular printing processes. Examples of optically variable security features include moire magnifiers, tilt images, holograms and thin-film elements.

The authenticity of valuable documents should not only be verifiable visually, but also mechanically. Machine verifiability offers a high level of security and is even mandatory in many technical applications, for example when processing banknotes. Devices such as automatic counting machines and vending machines should be able to recognize denominations and/or verify the authenticity of a banknote.

Known security threads and/or film elements with visual, in particular optically variable, security features do not have effective machine readability. It is only known to provide such security elements with codes that are based on substances that absorb in the infrared and are comparatively easy to recreate or forge. Magnetic substances, in turn, are generally clearly visible in both reflected light and transmitted light, so that they can disrupt the visual appearance of visual, especially optically variable, security features.

Security elements and/or valuable documents with substrates made of a polymer generally do not have any machine-readable security features integrated into the substrate. It is known, particularly in the area of banknotes with substrates made of polymer, to print magnetic codes. The disadvantage of this is that the printed magnetic coding is easily rubbed off, especially on banknotes that are in circulation. In addition, the magnetic substances applied to the banknotes can be removed, analyzed and/or recreated comparatively easily by a counterfeiter. Direct use of the removed magnetic substances for counterfeiting is also possible.

For example, printing inks with magnetic pigments for intaglio printing or gravure printing are out EP 2 417 207 B1 known.

Against this background, it is the object of the present invention to propose a solution to the aforementioned problems. There is a particular need for a security element with a machine-readable code that can be reliably checked for authenticity.

The present invention solves this problem through the appended independent claims. Preferred embodiments of the invention are specified in the claims dependent thereon.

According to a first aspect of the present invention, a security element is provided, preferably in the form of a security strip (also: film strip), security thread (also: film thread) or security patch (also: film patch). The security element has a machine-readable code and an optically variable security feature, which has a visual appearance that depends on the viewing angle. The machine-readable code comprises a magnetic coding (also: code), which is produced by printing technology using at least one opaque magnetic printing ink containing magnetic pigments, which is inserted or applied in at least one defined code area in such a way that the visual appearance of the optically variable security feature is at least partially determined by the at least one magnetic printing ink introduced or applied. The optically variable security feature comprises a microlens arrangement which covers the at least one code area in which the at least one magnetic printing ink is incorporated or applied.

In other words, it is proposed to generate a magnetic coding with the aid of at least one magnetic printing ink, which is incorporated or applied in particular in a code area that is visible when looking at the security element, for example as part of a positive or negative print. In the area of optically variable security feature, the magnetic color is applied in such a way that it or its magnetic pigments shapes or at least partially represents and thus determines the visual appearance of the optically variable security feature. The optically variable security feature advantageously comprises a microlens arrangement of, for example, spherical or aspherical lenses, rod lenses and / or cylindrical lenses, which covers the at least one code area in which the magnetic printing ink is incorporated or applied. The security element therefore has an internal, magnetic coding, which is well protected from mechanical abrasion by the microlens arrangement above it.

With an at least partial representation of the visual appearance of the optically variable security feature, it should be understood in particular that the magnetic printing ink is not necessarily the only color that is used to represent the optically variable security feature. It is further understood that additional elements, such as microstructures, microrecesses, relief structures or the like, can be present, which serve to generate the respective optically variable security feature.

Optically variable security features are designed, for example, as moiré magnifiers, tilt images, holograms and/or thin-film elements. The optically variable security feature proposed in this description uses the microlens arrangement, which has an optical imaging behavior suitable for this purpose, to generate the optically variable effect.

The at least one magnetic printing ink is an opaque color with a color impression that corresponds to a chromatic color, in particular red, green, blue, white or black.

Since the magnetic coding and the optically variable or changeable appearance are at least partially caused by the at least one magnetic printing ink, a mutually disruptive influence can be reduced. Visual and magnetic security features can therefore be recognized equally reliably.

In addition, the magnetic coding in the security element according to the invention is incorporated into the visual appearance of the optically variable security feature and is therefore correlated with it. This advantageously enables the implementation of further security levels to increase security against forgery, in particular in such a way that combinations of optically and magnetically detectable features are used.

The security element preferably serves to increase the barrier to forgery of a document of value. Documents of value include, in particular, banknotes, stocks, identification documents, credit cards, certificates, insurance cards and generally documents at risk of forgery, for example product security elements such as labels and packaging for high-quality products. In the context of this description, the term “document of value” includes not only completed, negotiable documents of value, but also preliminary stages of the documents of value such as security papers that do not have all the characteristics of a negotiable document of value, for example in sheet or roll form. The security elements have, for example, film elements in the form of threads, strips or patches that are applied to a document of value or at least partially introduced into a document of value, such as window security threads and pendulum security threads that are used to cover through openings in a document of value.

The detection or verification of the magnetic coding includes the detection of the magnetic printing ink or printing ink layer based on the magnetic properties of the associated magnetic pigments. The authenticity check of the security elements includes, for example, the determination of a magnetic field, a magnetic flux density, a magnetization, a remanence, a coercivity and/or a hysteresis. For detection, the magnetic properties of the magnetic pigments or their distribution can be recorded, for example, using known magnetic sensors.

In comparison to security elements with codings that are based on substances that absorb in the infrared spectral range, magnetic coding represents an increased barrier to counterfeiting. In addition, security elements, in particular foil or security threads, with optically variable properties and magnetic codings are more machine-readable than those that only contain Codings that absorb in the infrared spectral range are carried out.

The visual security feature is realized, for example in simple embodiments, by code areas provided visibly in or on the security element, which is or are printed with the at least one magnetic printing ink, preferably with different magnetic printing inks, for example in the form of motifs or symbols. The magnetic printing ink used is opaque and corresponds to a body color that represents the visual appearance of the optically variable security feature. The code area printed with such a magnetic printing ink provides a machine-readable magnetic coding that does not disturb the design or appearance of the visual security feature and cannot be visually separated from it, preferably without further aids.

It is understood that further printing inks with magnetic and/or non-magnetic pigments can be provided to represent the visual appearance of the security element, in particular the optically variable security feature. Furthermore, it goes without saying that different magnetic printing inks or additional colors with non-magnetic pigments can also be introduced or applied at least in some areas in a single code area.

Several code areas are provided in embodiments. In these cases, the code areas are, for example, spatially separated or at least partially overlapping areas in which the magnetic printing ink or inks are incorporated or applied.

According to advantageous embodiments, the optically variable security feature includes a Moire magnifier. Moire magnifiers are multilayer structures that typically include a focusing microlens arrangement, a transparent or translucent image layer with an arrangement of image elements, in particular microimages, and optionally a spacer layer between the micro-optical relief structure and the image layer. The image elements or microimages are enlarged or optically changed in some other way when viewed through the lenses. Further functional layers and/or auxiliary layers may also be present.

Preferably, the at least one magnetic printing ink is introduced into microrecesses, in particular into microrecesses for image elements such as microimages, which are embossed in a transparent or translucent image layer, in particular embossed lacquer layer, of the security element. Such configurations can therefore use the embossed micro-recesses of the optically variable security feature for an additional magnetic feature, namely as a code area for the magnetic coding.

Microwells for microimages, which are imaged or enlarged using micro-optical relief structures to produce the optically variable security feature, typically have very small dimensions and are therefore inherently difficult to imitate.

In advantageous embodiments, the magnetic pigments of the magnetic printing inks introduced into the microwells have a diameter of less than 2 μm. Such small-sized magnetic pigments are suitable, in particular, for coloring microwells for microimages of optically variable security features, for example Moire magnifiers, and for correspondingly providing code areas there for machine-readable, magnetic coding.

Alternatively or additionally, the security element has an opaque cover layer, which is formed as a color layer using the at least one magnetic printing ink. In such embodiments, larger areas can typically be realized, particularly in comparison to the microwells, which provide improved coding and machine readability. In such embodiments, the magnetic coding is, for example, a motif print with recesses, i.e. a so-called clear text or negative print or a positive print in the form of characters and/or patterns.

The magnetic pigments of the at least one magnetic printing ink, by means of which the opaque top layer is formed, preferably have a diameter between 2 μm to 10 μm, particularly preferably between 3 μm to 5 μm.

The opaque cover layer preferably has at least one recess which represents a motif, sign or symbol in negative print.

In advantageous embodiments, the machine-readable magnetic coding comprises at least one further opaque magnetic printing ink that contains magnetic pigments. The magnetic pigments of the various magnetic printing inks differ in terms of their coloring and/or magnetic properties, in particular in terms of their magnetic coercivity. The further magnetic printing ink is incorporated or applied as part of the magnetic coding, at least partially in a code area printed with the magnetic printing ink or in another code area of the security element.

According to possible exemplary embodiments, the at least two magnetic printing inks correspond to the same color and differ in terms of their magnetic properties, in particular in terms of their coercivity (“magnetic gemini”).

According to other possible exemplary embodiments, the at least two magnetic printing inks correspond to different colors and do not differ in terms of their magnetic properties, in particular in terms of their coercivity ("magnetic solitair").

Alternatively, the at least two magnetic printing inks differ both in terms of their coloring and in terms of their magnetic properties, in particular coercivity.

In advantageous embodiments, two or more magnetic printing inks are used whose magnetic pigments differ in terms of their magnetic coercivity. In this case, the code areas are characterized by areas with high magnetic coercivity and areas with low magnetic coercivity (so-called HiCoLoCo magnetic coding).

According to possible embodiments, at least two magnetic colors are incorporated or applied in different code areas, which are designed as areas spaced apart from one another when viewed from above or are arranged to overlap one another when viewed from above. For this purpose, for example, a code area is printed with at least two magnetic printing colors overlapping at least in some areas.

In advantageous embodiments, at least one of the magnetic printing inks is incorporated or applied in one of the code areas in a variable layer thickness, which represents a further security feature to increase security against forgery. The code areas are therefore not necessarily printed evenly, i.e. H. In particular, it is intended to print the code areas with magnetic printing inks and/or to provide an ink application that is variable in terms of its layer thickness.

According to possible embodiments of the invention, the magnetic pigments of the magnetic printing ink(s) comprise a magnetized or magnetizable core which is covered or coated by an opaque dye. It should be understood in particular that the magnetized or magnetizable core is surrounded by the opaque dye at least in some areas, preferably completely. Magnetic pigments with such a structure can be used, for example, according to the teachings of EP 2 152 821 B1 getting produced. The color layer can have an opaque body color that deviates from the core, for example red, green, blue, white, black and/or have a metallic shine, the metallic shine essentially corresponding to the shine of silver, gold, copper, chrome or another metal .

It was found that a magnetic printing ink which contains silver-coated pigments and is applied to one side of the security element opposite side is not visible or is only visible to a very limited extent. In this way, disruptive influences on visual or optically variable security features can also be avoided.

The security element is preferably designed in the form of a film or security thread, in particular a microlens thread.

A second aspect of the present invention relates to a valuable document, such as a banknote, which has a security element with the features described here. Advantages of the document of value secured with the security element according to the invention, for example with regard to security against forgery, result directly from the relevant disclosure of the security element according to the invention.

To secure the document of value, embodiments with several security elements are provided, which are in particular connected to this document of value in a precise register, for example in such a way that they cannot be detached from the document of value or only with considerable technical effort. Such embodiments enable the combination of magnetic coding and/or visual, in particular optically variable, security features, which are provided by different security elements in particular in such a way that the entirety of the different security elements result in overall information by which the authenticity of the document of value can be verified.

• aufgedruckte Sicherheitsmerkmale und magnetische Sicherheitsmerkmale eines Sicherheitsfadens;
• aufgedruckte Sicherheitsmerkmale und magnetische Sicherheitsmerkmale eines Sicherheitspatches und/ oder Sicherheitssteifens;
• magnetische Sicherheitsmerkmale eines Sicherheitsfadens und eines Sicherheitspatches und/oder Sicherheitssteifens;
• aufgedruckte Sicherheitsmerkmale und magnetische Sicherheitsmerkmale eines Sicherheitsfadens und magnetische Sicherheitsmerkmale eines Sicherheitspatches und/oder Sicherheitssteifens.

In possible exemplary embodiments, the combination of magnetic coding on a security thread and/or a security patch and/or security strips and/or others applied to the document of value results in Security elements printed on the value document provide overall information, with combinations preferably being provided:

• printed security features and magnetic security features of a security thread;
• printed security features and magnetic security features of a security patch and/or security strip;
• magnetic security features of a security thread and a security patch and/or security strip;
• printed security features and magnetic security features of a security thread and magnetic security features of a security patch and/or security strip.

The corresponding security elements or security features can in particular be applied to the front or back of the security document or banknote or embedded inside the security document or in one of the security elements.

By reading out the magnetic codes disclosed here, denomination recognition of a banknote provided with the security element is preferably made possible. In contrast to codings that are based on substances that absorb in the infrared spectral range, the magnetic coding can be read easily regardless of the orientation of the security element or a valuable document provided with the security element. This enables, in particular, reliable reading of banknotes with such security elements in a banknote processing machine, for example for denomination recognition. Magnetic encoding signals are generally stronger than those caused by magnetic printing elements such as SPARKS or magnetic numerals.

A third aspect of the present invention relates to a method for producing the security element according to the invention. Advantages of the manufacturing process result directly from the preceding and following description, in particular with reference to the security element.

When producing the security element, the magnetic coding is generated by printing technology by introducing or applying the at least one opaque magnetic printing ink containing magnetic pigments in at least one defined code area that is visible when viewed from above the security element and is covered by a microlens arrangement or is. The introduction or application of the magnetic printing ink in the at least one code area is thus carried out in such a way that the visual appearance of the optically variable security feature, which depends on the viewing angle, is at least partially determined by the at least one introduced or applied magnetic printing ink.

For example, an intaglio printing process or a gravure printing process can be used as a printing process.

The magnetic printing ink or inks is or are preferably used to produce image elements such as microimages of optically variable security features. Alternatively or additionally, the magnetic printing ink or inks are used to provide a substantially flat, in particular full-surface, print. In embodiments, for example, it is provided to generate a HiCoLoCo magnetic coding that is visually inconspicuous or hidden, in particular in the picture elements or in opaque white.

It is also possible to generate an additional or combined coding that is based on substances that are absorbent in the infrared spectral range (IR). In this context, IR-absorbing pigments are preferred The company SICPA (SICPA SA, AVE de Florian 41, 1008, Prilly, Switzerland) or printing inks sold under the trade name SICPATALK ^® .

Fig. 1

ein Wertdokument mit Sicherheitselementen in Aufsicht gemäß möglichen Ausführungsformen der Erfindung;

Fig. 2

ein weiteres Wertdokument mit Sicherheitselementen in Aufsicht gemäß möglichen Ausführungsformen der Erfindung;

Fig. 3

ein Sicherheitselement mit einem optisch variablen Sicherheitsmerkmal und einer magnetischen Codierung gemäß einer möglichen Ausführung der Erfindung in einer schematischen Querschnittsdarstellung, wobei die magnetische Codierung drucktechnisch durch magnetische Pigmente einer Magnetdruckfarbe gebildet ist;

Fig. 4

ein Sicherheitselement mit einem optisch variablen Sicherheitsmerkmal und einer magnetischen Codierung gemäß einer möglichen Ausführung der Erfindung in einer schematischen Querschnittsdarstellung, wobei die magnetische Codierung drucktechnisch durch unterschiedliche magnetische Pigmente zweier Magnetdruckfarben gebildet ist;

Fig. 5

ein Sicherheitselement mit Codebereichen einer magnetischen Codierung in einer schematischen Querschnittsdarstellung, die als bereichsweise opake Deckschicht ausgeführt ist;

Figuren 6 bis 14

Ausführungsformen des erfindungsgemäßen Sicherheitselement mit magnetischen Codierungen in Aufsicht, die auf zwei unterschiedlichen Magnetdruckfarben basieren;

Fig. 15a bis 15e

schematische Ausführungsbeispiele mit verlaufend bzw. ungleichmäßig bedruckten Codebereichen in Aufsicht, welche visuelle Sicherheitsmerkmale darstellen.

Further aspects, features and advantages of the present invention will become clear from the following detailed description of preferred embodiments and variants with reference to the accompanying figures, which show:

Fig. 1

a document of value with security elements in top view according to possible embodiments of the invention;

Fig. 2

a further document of value with security elements in supervision according to possible embodiments of the invention;

Fig. 3

a security element with an optically variable security feature and a magnetic coding according to a possible embodiment of the invention in a schematic cross-sectional representation, the magnetic coding being formed in printing terms by magnetic pigments of a magnetic printing ink;

Fig. 4

a security element with an optically variable security feature and a magnetic coding according to a possible embodiment of the invention in a schematic cross-sectional representation, the magnetic coding being formed in printing terms by different magnetic pigments of two magnetic printing inks;

Fig. 5

a security element with code areas of a magnetic coding in a schematic cross-sectional representation, which is designed as a partially opaque cover layer;

Figures 6 to 14

Embodiments of the security element according to the invention with magnetic codings in top view, which are based on two different magnetic printing inks;

Fig. 15a to 15e

Schematic exemplary embodiments with gradient or unevenly printed code areas in supervision, which represent visual security features.

The invention is explained below by way of example using the drawings, which illustrate specific exemplary embodiments of the invention. These exemplary embodiments are described in detail and enable those skilled in the art to technically implement the invention. The embodiments described are not mutually exclusive, but rather complement each other. In this respect, a specific feature, a specific structure or a specific property that is described in connection with one embodiment can also be implemented in connection with other embodiments without departing from the subject matter of the invention. Furthermore, the position or arrangement of individual elements or steps within the described embodiments can of course be modified without departing from the subject matter of the invention. Therefore, the following description of the accompanying figures is not to be understood as limiting, since the scope of the invention is defined exclusively by the appended claims and also includes variants and equivalents which are not expressly described below.

Fig. 1 shows a schematic top view of a document of value 100, which is provided with different security elements 10, which are preferably arranged in a defined position, in particular in register, relative to one another and with respect to the document of value 100. Shown are security elements 10, which are designed, for example, as security thread 10a, window security thread 10b, security strip 10c or security patch 10d. At the in Fig. 1 The value document 100 shown is, for example, a banknote with a substrate made of cotton paper, in which the security thread 10a is embedded. The security thread 10b is a so-called window thread, which is embedded in the substrate of the document of value 100 in such a way that it alternately appears visibly in windows 11b on opposite sides of the document of value 100.

Fig. 1 shows a variety of different security elements 10, 10a, 10b, 10c, 10d, which do not necessarily have to be implemented in their entirety as shown. It goes without saying that even a single security element 10, especially when applied in a register-accurate manner, can provide a sufficiently forgery-proof security feature for the document of value 100. In preferred embodiments, several security elements 10 can be provided to increase security against forgery, such as any combination of the following Fig. 1 safety features shown.

Fig. 2 shows an example of another valuable document 100 with security elements 10, which are designed as security strips 10c or security patch 10d. At the in Fig. 2 The value document 100 shown can be, for example, a banknote with a polymer substrate, in particular made of polyethylene terephthalate, or a film composite banknote.

The security elements 10 are provided with a machine-readable code that includes magnetic coding, which is printed in code areas C1, C2, C3 is generated by at least partially introduced or applied opaque magnetic printing inks M1, M2, M3. Corresponding embodiments show examples Figures 3 to 5 in cross section and the Figures 6 to 15 under supervision.

The magnetic printing inks M1, M2, M3 contain magnetic pigments of different types such that they differ in terms of their coloring and/or magnetic properties, for example in terms of their coercivity. The magnetic coding encodes, for example, information assigned to the security element 10 or the document of value 100, such as a denomination or similar. In other words, for example, the denomination of the document of value 100 can be recognized based on the magnetic coding. The authenticity check of the security elements 10 includes the detection of the magnetic printing inks M1, M2 or their magnetic pigments using magnetic sensors, preferably in combination with the detection of an optically variable security feature, which is correlated with the magnetic coding.

The Figures 3 to 15 show security elements 10 with magnetic codings that provide part of a visual security feature in the code areas C1, C2, C3, in particular the magnetic printing inks M1, M2 introduced in the code areas C1, C2 provide an optically variable security feature (see Figs. 3, 4 ).

The code areas C1, C2, C3 visible when looking at the front of the security element 10 are generated by magnetic printing inks M1, M2, M3 which are inserted or applied there and which contain magnetic pigments.

Fig. 3 shows a security element 10 in cross section, which implements a visually detectable, optically variable security feature, in particular a Moire magnifier. The security element 10 has a multi-layer structure, with a microlens arrangement 11 forming a top layer on the visible side or when viewed from above and thus protecting the underlying layers from mechanical abrasion. The microlens arrangement 11 shown comprises a plurality of microlenses 18 which are focused on underlying image elements 16 (also: micro images). When viewed through the microlens arrangement 11, the image elements 16 are enlarged or otherwise optically changed to produce the optically variable effect.

The Moire Magnifier Fig. 3 further comprises a spacer layer 12, which is arranged between the microlens arrangement 11 and an image layer 13 containing the image elements 16, and functional layers 14, 15. Further machine-readable features can be implemented in the functional layer 14. The further functional layer 15 consists, for example, of an adhesive layer for the intended attachment of the security element 10 to the document of value 100. In the embodiment shown, the image layer 13 consists of a transparent embossing varnish in which micro-recesses 17 are embossed. Alternatively, the image layer 13 may be formed from a translucent material. The micro-wells 17 are filled with the same magnetic printing ink M1 and form the image elements 16 as so-called microimages or microimages.

The microlenses 18 and the image elements 16 each form a two-dimensional arrangement. The image layer 13 and the microlens arrangement 11 produce the optically variable security feature. The security feature optionally contained in the functional layer 14 is based, for example, on substances introduced there that are absorbent, fluorescent and/or in the infrared spectral range are phosphorescent. According to other variants, the functional layer 14 has primers or color-accepting layers.

Fig. 4 shows another security element 10 with one Fig. 3 largely analogous structure. In contrast to the exemplary embodiment of Fig. 3 some of the micro-wells 17, which form the image elements 16, are filled with two different magnetic printing inks M1, M2, which differ in terms of their coercivity and thus provide a so-called HiCoLoCo coding.

In the in Figs. 3 to 5 In the exemplary embodiments shown, the code areas C1, C2 are generated by filling the microwells 17 not with any colored substance, but with a magnetic printing ink M1, M2 or with several magnetic printing inks M1, M2. As a result, the magnetically readable or magnetic code is generated in an internal area of the security element 10, which is well protected from external mechanical influences, in particular when the security element 10 or the value document 100 provided with the security element 10 is in circulation.

Since the microwells 17 are at least partially filled with magnetic printing inks M1, M2 and are optically imaged by means of the microlens arrangement 11, the magnetic printing inks M1, M2 at least partially determine a visual appearance that depends on the viewing angle.

Due to the small spatial extent of the microwells 17, the magnetic pigments of the magnetic printing inks M1, M2 that are introduced there preferably have a diameter of less than 2 μm.

The magnetic pigments of the magnetic printing inks M1, M2, M3 preferably comprise a magnetized or magnetizable core which is covered by an opaque dye. The dye corresponds to an opaque body color, for example red, green, blue, black or white and/or is metallically shiny, for example corresponding to the metallic luster imparted by silver, gold, copper, chrome or another metal.

According to possible variants, at least two of the magnetic printing inks M1, M2, M3 correspond to the same color and differ in terms of their magnetic properties, in particular their coercivity. In alternative embodiments, the at least two magnetic printing inks M1, M2, M3 correspond to different colors and do not differ in terms of their magnetic properties. In general, the magnetic printing inks M1, M2, M3 can differ both in terms of their coloring and their magnetic properties.

In a further exemplary embodiment, not shown in more detail, the in Fig 4 Functional layer 14 shown is designed as an opaque, i.e. essentially opaque, cover layer. The opaque cover layer is printed in areas on the side facing away from the microlens arrangement 11 with magnetic printing inks M1, M2, M3, so that they do not appear visible on the visible side or when viewed from above and thus the optically variable appearance of the optically variable security feature is not disturbingly influenced. Flat printing with magnetic printing inks M1, M2, M3 enables the creation of larger code areas C1, C2, C3, which can be read reliably using common magnetic sensors. In order to generate signatures that are even easier to capture, M3 magnetic printing inks with magnetic pigments are preferred used, which have a larger diameter compared to the pigments introduced into the microwells 17, for example between 2 μm to 10 μm, particularly preferably between 3 μm to 5 μm.

Optionally, the back of the security element 10, in particular the security thread 10a, 10b, can also be printed with a magnetic printing ink M1, M2, M3. In this case too, larger areas can typically be realized compared to the micro-wells 17, which ensure reliable coding and machine readability. In particular, a magnetic printing ink containing magnetic pigments coated with silver is not visible on the front of the security element 10 in incident light if it is applied to the back of the security element 10.

Fig. 5 shows a further exemplary embodiment of the security element 10, which has an optically variable security feature by means of an optical relief structure 11 and image elements 16 analogous to that in Fig. 4 illustrated version. In this regard, please refer to the description of Fig. 4 described.

The exemplary embodiment according to Fig. 5 comprises a functional layer which is formed as an opaque cover layer 19 of the magnetic printing ink M3 and defines at least one further, relatively large code area C3 of the magnetic coding. Accordingly, the magnetic printing ink M3 preferably has magnetic pigments whose diameter is between 2 μm and 10 μm, particularly preferably between 3 μm and 5 μm.

The opaque top layer 19 of the Fig. 5 forms a color layer with recesses 20 in the form of a negative print (clear text), which is particularly visible when viewed in transmitted light.

It goes without saying that the more magnetic printing inks M1, M2, M3 are used, and the more complex the shapes of the code areas C1, C2, C3 or the partial areas within the individual code areas C1, the more difficult the machine-readable, magnetic codings are to forge , C2, C3 are each applied with a magnetic printing ink M1, M2, M3 or a mixture of magnetic printing inks M1, M2, M3. Increasing the number of code areas C1, C2, C3 also leads to an increase in security against forgery.

The Figures 6 to 9 show various, essentially rectangular security elements 10 with strip-shaped code areas C1, C2 in supervision. The code areas C1, C2 are visible from above and form part of an optically variable security feature.

Fig. 6 shows a simple version with two code areas C1, C2, which extend as strips 24 over the entire longitudinal extent of the security element 10 and are separated from one another by an unprinted area 22 in between. For example, the code areas C1, C2 implement a HiCoLoCo coding, in which the magnetic pigments of the magnetic printing ink M1 of the code area C1 have a higher coercivity than the magnetic pigments of the magnetic printing ink M2, which are incorporated or applied in the code area C2.

Fig. 7 shows a security element 10 with two strips 24 arranged parallel to one another, which are alternately printed with magnetic printing inks M1, M2 and thus define alternating code areas C1, C2. The two longitudinal strips 24 arranged parallel to one another are separated from one another by the unprinted area 22.

At the in Fig. 8 In the embodiment shown, the security element 10 is strip-shaped and printed alternately in the longitudinal direction with magnetic printing inks M1, M2 in such a way that essentially rectangular code areas C1, C2 of different sizes are formed, which are spaced apart from one another by unprinted areas 22.

The term “unprinted” is to be understood here to mean that no magnetic printing inks M1, M2, M3 or their pigments are incorporated or applied in the unprinted area 22.

Fig. 9 shows one of the Fig. 8 Similar version, in which the code areas C1, C2 are designed as diagonal stripes.

10 and 11 show further security elements 10, which are visible as circular structures when viewed from above. When executing the Fig. 10 the code areas C1, C2 are designed as concentric circular rings which are arranged around a central unprinted area 22. Fig. 10 shows a circular security element 10 with strip-shaped code areas C1, C2, which are arranged parallel to one another and are spaced apart from one another on the visible side.

Fig. 12 shows a security element 10 with a hexagonal appearance in supervision. The code areas C1, C2 containing magnetic printing inks M1, M2 are designed as diagonal stripes.

Fig. 13 shows a substantially square security element 10 with code areas C1, C2, which are spatially separated from one another by a cross-shaped, unprinted area 22.

Fig. 14 shows a top view of a security element 10, in which two strip-shaped code areas C1, C2 overlap in sections in an overlap section 26.

Fig. 15a to 15d show exemplary code areas C1, C2 of security elements 10, which are printed unevenly with magnetic printing inks M1, M2 or in which the magnetic printing inks M1, M2 are incorporated or applied in variable layer thickness.

Fig. 15e shows an exemplary embodiment with two code areas C1, C2, which are printed unevenly with magnetic printing inks M1, M2 and overlap in the overlap area 26.

In a method for producing the security element, the magnetic coding is generated using printing technology. At least one opaque magnetic printing ink M1, M2, M3 with magnetic pigments is introduced or applied in defined code areas C1, C2, C3 of the security element 10 (cf. Figs. 3 to 15 ), in such a way that it provides at least part of an optically variable security feature.

For this purpose, the micro-recesses 17 of a moiré magnifier can be filled with the same magnetic printing ink M1, as in particular in Figure 3 shown.

Alternatively, the micro-wells 17 can also be printed with different magnetic printing inks M1, M2, M3 to provide the image elements 16.

Also the opaque top layer 19 of the Fig. 5 can, for example, be a single magnetic printing ink M3 or different magnetic printing inks M1, M2, M3 are formed and in particular encode characters, symbols or other motifs as recesses 20 in negative print.

The code areas C1, C2, C3 are arranged below the microlens arrangement 11 to provide the optically variable security feature. For this purpose, the microlens arrangement 11 will be connected to the image layer 13, for example by lamination, before or after printing with magnetic inks M1, M2, M3.

The invention is explained above by way of example using the drawings, which illustrate specific exemplary embodiments of the invention. These exemplary embodiments are described in detail above and enable those skilled in the art to technically implement the invention. The embodiments described are not mutually exclusive, but rather complement each other. In this respect, a specific feature, a specific structure or a specific property that is described in connection with one embodiment can also be implemented in connection with other embodiments without departing from the subject matter of the invention. Furthermore, the position or arrangement of individual elements or steps within the described embodiments can of course be modified without departing from the subject matter of the invention. Therefore, the description of the accompanying figures is not to be understood as limiting, since the scope of the invention is defined exclusively by the appended claims and also includes variants and equivalents that are not expressly described.

Claims (15)

Security element (10), preferably in the form of a security strip (10c), security thread (10a, 10b) or security patches (10d), with a machine-readable code and an optically variable security feature, which has a visual appearance that depends on the viewing angle, wherein the machine-readable code is a magnetic coding which is produced by printing technology using at least one opaque magnetic printing ink (M1, M2, M3) containing magnetic pigments, which is incorporated or applied in at least one defined code area (C1, C2, C3), that the visual appearance of the optically variable security feature is at least partially determined by the at least one magnetic printing ink (M1, M2, M3) introduced or applied, wherein the optically variable security feature comprises a micro-optical microlens arrangement (11) which covers the at least one code area (C1, C2, C3) in which the at least one magnetic printing ink (M1, M2, M3) is incorporated or applied. Security element (10) according to one of the preceding claims, characterized in that the optically variable security feature comprises a Moire magnifier. Security element (10) according to one of the preceding claims, characterized in that the at least one magnetic printing ink (M1, M2) is introduced into microwells (17), in particular for microimages, which are in a transparent or translucent image layer (13) of the security element (10 ) are embossed. Security element (10) according to one of the preceding claims, characterized in that the magnetic pigments of the magnetic printing ink (M1, M2) introduced into the microwells (17) have a diameter of less than 2 µm. Security element (10) according to one of the preceding claims, characterized in that an opaque cover layer (19) of the security element (10) is formed as a color layer of the at least one magnetic printing ink (M3). Security element (10) according to claim 5, characterized in that the magnetic pigments of the at least one magnetic printing ink (M3), by means of which the opaque cover layer (19) is formed, have a diameter between 2 µm to 10 µm, preferably between 3 µm to 5 µm , exhibit. Security element (10) according to claim 5 or 6, characterized in that the opaque cover layer has at least one recess which represents a motif, sign or symbol in negative print. Security element according to one of the preceding claims, characterized in that the machine-readable magnetic code comprises at least one further, opaque magnetic printing ink (M1, M2, M3) containing magnetic pigments, wherein magnetic pigments of different magnetic printing inks (M1, M2, M3) differ in terms of coloring and / or magnetic properties, especially with regard to magnetic coercivity. Security element (10) according to claim 8, characterized in that at least two of the magnetic printing colors (M1, M2, M3) correspond to the same color and differ in terms of their magnetic properties, in particular their coercivity, or
at least two of the magnetic printing inks (M1, M2, M3) correspond to different colors and do not differ in terms of their magnetic properties, in particular their coercivity. Security element (10) according to claim 8 or 9, characterized in that at least two of the magnetic printing inks (M1, M2, M3) are introduced or applied in different code areas (C1, C2), which, when viewed from above, are designed as areas spaced apart from one another and/or are arranged overlapping each other when viewed from above. Security element (10) according to one of the preceding claims, characterized in that the magnetic pigments of the at least one magnetic printing ink (M1, M2, M3) comprise a magnetized or magnetizable core which is covered by an opaque dye. Security element (10) according to one of the preceding claims, characterized in that the at least one magnetic printing ink (M1, M2) is incorporated or applied in one of the code areas (C1, C2) in a variable layer thickness. Security element (10) according to one of the preceding claims , characterized in that the security element is designed in the form of a film thread (10a, 10b), in particular a microlens thread. Document of value (100) with at least one security element (10) according to one of claims 1 to 13. Method for producing a security element (10) according to one of claims 1 to 13, characterized in that the magnetic coding is produced by printing technology in that the at least one opaque magnetic printing ink (M1, M2, M3) containing magnetic pigments is in at least one in The defined code area (C1, C2, C3) visible from the top view of the security element (10) is inserted or applied and covered by a microlens arrangement (11), so that the visual appearance of the optically variable security feature, which depends on the viewing angle, is at least partially influenced by the at least an inserted or applied magnetic printing ink (M1, M2, M3).

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