DE102010054853A1 - Security element with marking - Google Patents

Abstract

The invention relates to a security element (12) for securing objects of value, with an optically variable effect layer (40) which conveys different color impressions at different viewing angles, an optically non-variable color layer (32) which is at least in an overlap area of the effect layer (40 ) is covered, and there contains at least a first sub-area (34) with a first fixed color impression and a second sub-area (36) with a different second fixed color impression, an individualizing marking generated at least in the overlap area of the effect layer (40) and color layer (32) (14), each showing the first and second fixed color impression in a sub-area (16, 18), the sub-areas (34, 36) of the color layer (32) and the effect layer (40) being coordinated with one another so that the variable Color impression of the effect layer (40) under a predetermined first viewing angle a solid color impression.

Description

The invention relates to a security element for securing valuables, which has an individualizing marking. The invention also relates to a data carrier with such a security element and to a production method for such a security element.

Data carriers, such as valuables or identity documents, but also other valuables, such as branded goods, are often provided with security elements for the purpose of security, which permit verification of the authenticity of the data carrier and at the same time serve as protection against unauthorized reproduction.

Security elements with viewing-angle-dependent effects play a special role in the authentication of authenticity since they can not be reproduced even with the most modern copiers. In this case, the security elements are equipped, for example, with optically variable elements which give the viewer a different image impression at different viewing angles and, for example, show a different color or brightness impression and / or another graphic motif depending on the viewing angle.

Based on this, the present invention has for its object to provide a security element of the type mentioned above with high security against imitation and attractive visual appearance, which can ideally be checked for authenticity even by laymen.

This object is solved by the features of the independent claims. Further developments of the invention are the subject of the dependent claims.

• – eine optisch variable Effektschicht, die unter unterschiedlichen Betrachtungswinkeln unterschiedliche Farbeindrücke vermittelt,
• – eine optisch nicht-variable Farbschicht, die zumindest in einem Überdeckungsbereich von der Effektschicht überdeckt ist, und dort zumindest einen ersten Teilbereich mit einem ersten festen Farbeindruck und einen zweiten Teilbereich mit einem unterschiedlichen zweiten festen Farbeindruck enthält, und
• – eine zumindest im Überdeckungsbereich von Effektschicht und Farbschicht erzeugte individualisierende Kennzeichnung, die jeweils in einem Teilbereich den ersten bzw. zweiten festen Farbeindruck zeigt,
• – wobei die Teilbereiche der Farbschicht und die Effektschicht so aufeinander abgestimmt sind, dass der variable Farbeindruck der Effektschicht unter einem vorbestimmten ersten Betrachtungswinkel dem ersten festen Farbeindruck entspricht.

According to the invention contains a security element of the type mentioned

• An optically variable effect layer which gives different color impressions at different viewing angles,
• - An optically non-variable ink layer, which is covered at least in a coverage area of the effect layer, and there contains at least a first portion having a first solid color impression and a second portion having a different second solid color impression, and
• An individualizing marking produced at least in the overlapping area of the effect layer and the color layer, which in each case shows the first or second fixed color impression in a partial area,
• - Wherein the partial areas of the color layer and the effect layer are coordinated so that the variable color impression of the effect layer corresponds to the first solid color impression at a predetermined first viewing angle.

The term "solid color impression" refers to a color impression that does not change with the viewing angle. Conventional printing inks usually have such a solid color impression. In contrast, there is a color impression that changes with the viewing angle, such as the color shift effect of an optically variable layer. Such a color impression changing with the viewing angle is referred to in the context of this description as a "variable color impression". In the context of the present invention, the term "variable color impression" encompasses any color impression that changes with the viewing angle and can be perceived by a viewer. In addition to the already mentioned color shift effect such a "variable color" but also z. B. be perceivable by a viewer, viewing angle dependent brightness or contrast change.

As a result of the tuning carried out according to the invention, the first subarea of the identification appears to the observer from the first viewing angle with the same color impression as the effect layer and is therefore hidden. On the other hand, it is possible to see from the first viewing angle the second partial area of the marking, which shows a different, fixed color impression and therefore stands out contrasting from the effect layer. From other viewing angles, the first portion of the marking is recognizable, since its fixed color impression then no longer coincides with their color impression due to the change in the variable color impression of the effect layer. The predetermined first viewing angle may, for example, correspond to a vertical view of the security element. It goes without saying that the principle according to the invention will not be abandoned if the effect layer and a partial area do not have the exact same color impression at a certain viewing angle, but the viewer perceives the color impression of the effect layer and the partial area as the same, although the color impression of the partial area and the effect layer only are essentially the same. For the concept according to the invention, therefore, it is ultimately decisive that the observer perceives the color impression of a specific subarea and the color impression of an effect layer as the same, without it being necessary to have an exact correspondence in the sense of defining a particular color space. As far as in the present application of the same or the same color impression of two areas of the security element according to the invention Thus, these formulations also include color impressions of two areas that are substantially the same.

It is also understood that the security element according to the invention can have several areas in which an optically variable effect layer according to the invention and an optically non-variable color layer according to the invention having at least two partial areas with first and second fixed color impressions are present. It is conceivable z. B. a security element having a first effect layer and an optically non-variable color layer with first and second sub-area in a first area, wherein the first portion conveys a first solid color impression and the second portion a second fixed color impression. In a second region of this security element, a second optically variable effect layer is arranged, which is combined with a further optically non-variable color layer having two partial areas and two fixed color impressions, the color impression being different from the first and second optically variable effect layer and from the respectively assigned partial areas can be. Also, the first and second optically variable effect layer and the associated subregions may have different structures according to the invention.

Preferably, the subregions of the color layer and the effect layer are even matched to one another such that the variable color impression of the effect layer corresponds to the second fixed color impression at a predetermined second viewing angle. The predetermined second viewing angle may, for example, correspond to an oblique view of the security element. In this case, only the second subarea of the marking can be seen when viewed vertically, while only the first subarea of the marking can be seen when viewed obliquely. The other subarea remains hidden to the viewer due to the color match with the effect layer.

According to an advantageous variant of the invention, the effect layer is opaque or semitransparent. The marking is formed in this variant in particular by recesses of the effect layer or by local, generated by the action of laser radiation, transparent modifications of the effect layer. The recesses or the transparent modification regions respectively provide a local view of the color layer arranged below the effect layer.

According to another, likewise advantageous variant of the invention, the effect layer is essentially transparent. In this variant, a laser-sensitive covering intermediate layer is arranged between the effect layer and the color layer and the marking is formed by recesses or local transparent modifications of the intermediate layer, which are respectively produced by the action of laser radiation. In the areas which are not exposed to laser radiation, the effect layer is then present against the background of the covering intermediate layer, while in each case the view of the color layer arranged beneath the effect layer and the intermediate layer is released in the areas acted upon by the recesses or the transparent modification areas.

It is understood that the above-described variant with essentially transparent formed effect layer and laser-sensitive, opaque intermediate layer between this effect layer and a color layer in principle also executable with an effect layer, the laser radiation is not absorbed and semitransparent or even opaque. As described above, the application of laser radiation causes the intermediate layer to be provided with recesses or local, transparent modifications, so that, in turn, interesting color-shift effects according to the invention result for the viewer.

The optically variable appearance of the effect layer is especially effective when the opaque interlayer is dark, especially black. The intermediate layer may contain, for example in a transparent binder, an IR absorber such as carbon black CIPBl.7 or graphite, which is ablated on laser application with an infrared laser. Other suitable materials for the laser sensitive opaque interlayer, in particular the candidate absorbent blend components, can be found in the references WO 2005/108110 A1 . DE 10 2008 049 512 A1 and DE 10 2006 008 247 are taken from the disclosures of which are included in the present description.

In a further advantageous variant of the invention, the effect layer is substantially transparent and comprises the ink layer itself, at least one laser-sensitive ink mixture, as described for example in the cited documents DE 10 2008 049 512 A1 . DE 10 2006 008 247 and WO 2005/108110 A1 is described. The marking is formed in this embodiment by local color changes in the laser-sensitive color mixture, which are generated by the action of laser radiation. For example, the color mixture may contain first and second colored pigments, the second colored pigments being present in a core-shell particle whose shell is surrounded by an ablation-promoting functional layer, as in US Pat DE 10 2008 049 512 A1 described. By laser application, the second colored pigments can then be removed from the color mixture, so that the color impression in the marked areas is determined only by the first pigments. In order to produce different solid color impressions, different first colored pigments may be provided in different partial areas of the color layer, or the color mixture may contain a plurality of colored pigments which can be removed at different laser intensities.

In a preferred embodiment of the invention, the color layer shows a color gradient between the first and second solid color impression. Such a color gradient can be generated for example by a plurality of color elements with different colors. In a particularly expedient design, however, the color gradient is produced by a multiplicity of juxtaposed first and second color elements, which respectively show the first and second fixed color impressions, and their area proportions vary spatially in order to produce a quasi-continuous color transition from the first to the second color impression. The first and second color elements may in particular be juxtaposed color stripes or halftone dots.

Of course, it is also conceivable that, for example, for an optically non-variable ink layer with three color impressions a color between the first and second and between the second and third color impression is produced by the fact that by means of the method described above, a color gradient between the respective solid color impressions is produced. At present, however, the above-described embodiments with a color gradient between first and second solid color impression of a color layer with two partial regions are particularly preferred because of the simpler manufacture and the impressive tilting effect resulting for the viewer.

Also conceivable is an embodiment in which the optically non-variable ink layer additionally a further security feature, such. B. has microtext, which can be used, for example in the field of customization in addition as an authenticity feature.

Furthermore, it is conceivable that an effect layer has an optically variable diffraction structure, which shows the variable color impression according to the invention on the basis of their specific diffraction structures.

In all designs, the color layer and / or the effect layer may contain a feature substance, in particular a magnetic, electrically conductive, luminescent or infrared-absorbing feature substance. If an intermediate layer is provided, it may also contain such a feature substance.

The optically variable effect layer preferably contains single or multilayer interference pigments or cholesteric liquid crystal pigments.

Such interference pigments have, as well as certain applicable within the scope of this invention surface layer structures, optically effective interference layers. Such interference layers typically have a thin film structure and include, for. For example, in the case of a multilayer thin film structure, a reflective layer, an absorber layer, and one or more intervening dielectric spacer layers are based on, for example, mica, SiO _2, or Al ₂ O ₃ . Such interference layers are referred to as one or more layers according to the number of dielectric layers. Printing inks with interference layer pigments, for example, under the name Iriodin ^® (single layer) or Colorcrypt ^® (multi-layer) marketed by Merck KGaA.

Printing inks with multilayer interference-layer pigments are further z. B. sold under the name OVI ^® by the company SICPA.

Also, effect layers with holographic pigments or with pigments having a constant diffraction structure come into consideration. In particular, holographic pigments can be prepared by comminuting holographic films. They can be both transparent and opaque.

In a further development of the invention, the individualizing marking is continued outside the overlapping area, in particular by a local change of a standard color or a local change of a substrate, for example by a foaming or blackening of the substrate. The marking or the security element can thereby be integrated into the design of the data carrier to which the security element is applied. Such a continuation of the marking in the surrounding data carrier is particularly well feasible if the security element, as proposed according to the invention, is subsequently individualized. In general, the individualizing marking outside the covering area can also be continued by the fact that a part of the marking is already arranged outside the covering area. As a rule, however, register errors occur during such a continuation of the individualizing characteristic, so that the embodiment described above continues with the marking in the surrounding area Data carrier by subsequent customization is very particularly preferred.

The individualizing marking can be executed rasterized in advantageous embodiments of the invention and then preferably represent a screened grayscale image or a screened color halftone image.

The color layer and the effect layer can be coated, at least in the covering area, with a lacquer layer which compensates for a different matt or gloss effect in the area of the marking. In this way it can be avoided that marking parts, which should actually be provided from a certain viewing angle due to their color match with the effect layer, can still be recognized due to different matt or gloss effect.

Also, by certain additives in the optically non-variable ink layer can be avoided that identification parts, which should actually be hidden due to their color match with the effect layer from a certain viewing angle, are still recognized by the viewer under certain lighting and observation conditions. These additives may be, for example, silvery shimmering pigments, which give the optically non-variable color layer a shimmering color impression, the color impression of the arranged above optically variable effect layer with z. B. also shimmering, optically variable pigments is very well approximated. In other words, the glimmer of the areas in question distracts the eye of the observer from the slight deviation of the color impressions that may be present, whereby the color impressions of these areas subjectively perceived by the observer are the same.

The subareas of the identification with the first and second color impressions preferably represent information that is related to one another or complementary to one another. For example, the information of the first subarea can repeat the information of the second subarea or supplement it to form a total information.

Advantageously, the security element comprises a substrate on which the color layer, any intermediate layer and the effect layer are arranged in this order. Suitable substrate material is any type of paper, in particular cotton paper or even paper, which contains a proportion x polymeric material in the range of 0 <x <100 wt .-%. Further, the substrate material may also be a plastic film, for example a polyester film. Such a film may be monoaxially or biaxially stretched. The stretching of the film, inter alia, leads to it receiving polarizing properties that can be used as another security feature. Since the security element according to the invention is designed for observation in a top view, the substrate is preferably opaque. Of course, a transparent or translucent substrate can be used if, for example, the optically non-variable ink layer is opaque, or else the security element is placed on a reflective, in particular white background. Such a transparent or translucent substrate may also be a plastic film, which is arranged in the region of a window-like opening in a data carrier. At present, however, opaque or substantially opaque substrate materials for the security element are preferred because the security element according to the invention for the viewer z. B. are more attractive because of their higher color saturation in the rule.

The invention also encompasses a data carrier with a security element of the type described. The data carrier may be, in particular, a value document such as a banknote, in particular a paper banknote, a polymer banknote or a foil composite banknote, but also an identity card, such as a credit card. a bank card, a cash card, an authorization card, an identity card or a pass personalization page.

The individualizing marking is advantageously continued beyond the security element into the data carrier. This can be done for example by the foaming or blackening of the data carrier substrate or by changing a layer present on the data carrier, such as the local change of a color layer or the demetallization of a metal layer. Due to the subsequent individualization by means of laser application, this continuation can be carried out in register.

• – ein Substrat bereitgestellt wird,
• – eine optisch nicht-variable Farbschicht aufgebracht wird, die in einem Überdeckungsbereich zumindest einen ersten Teilbereich mit einem ersten festen Farbeindruck und einen zweiten Teilbereich mit einem zweiten festen Farbeindruck enthält,
• – eine optisch variablen Effektschicht aufgebracht wird, die unter unterschiedlichen Betrachtungswinkeln unterschiedliche Farbeindrücke vermittelt, und die in dem Überdeckungsbereich die optisch nicht-variable Farbschicht überdeckt,
• – wobei die Teilbereiche der Farbschicht und die Effektschicht so aufeinander abgestimmt sind, dass der variable Farbeindruck der Effektschicht unter einem vorbestimmten ersten Betrachtungswinkel dem ersten festen Farbeindruck entspricht, und
• – zumindest im Überdeckungsbereich von Effektschicht und Farbschicht eine individualisierende Kennzeichnung erzeugt wird, die jeweils in einem Teilbereich den ersten bzw. zweiten festen Farbeindruck zeigt.

The invention further relates to a method for producing a security element for securing valuables, in which

• A substrate is provided,
• An optically non-variable ink layer is applied which, in an overlapping region, contains at least a first partial region with a first solid color impression and a second partial region with a second solid color impression,
• - An optically variable effect layer is applied, the different color impressions from different viewing angles mediated, and covered in the overlap area, the optically non-variable color layer,
• - Wherein the portions of the ink layer and the effect layer are coordinated so that the variable color impression of the effect layer at a predetermined first viewing angle corresponds to the first solid color impression, and
• - At least in the coverage area of the effect layer and color layer an individualizing marking is generated, each showing the first or second fixed color impression in a sub-area.

The individualizing marking is preferably produced by laser application, in particular by an infrared laser, such as a CO ₂ laser, Nd: YAG laser or Nd: YVO ₄ laser. The individualizing marking is advantageously produced only after the production of the layer sequence of substrate, ink layer and effect layer in a separate production step.

The individualization by means of laser application enables a subsequent individualization of the security element, so that the individualizing information at the time of production of the layer sequence does not yet have to be known. Rather, the individualization can be made later, for example when applying the security element to a specific value document. In this case, for example, the serial number of a banknote can be detected via a reading device and the read serial number can be inscribed as an individualizing identifier in the security element. Also, in the case of subsequent individualization, the identification can continue beyond the area of the security element with register accuracy in the surrounding data carrier and thus the counterfeit security of the security element / data carrier system can be further increased.

The color layer and / or the effect layer will preferably be applied in a printing process. Particularly preferably, both layers are printed. In principle, the effect layer can be applied using all common printing methods, such as screen printing, flexographic printing, gravure printing and intaglio printing. However, a screen or flexographic printing process is currently preferred. The gravure printing process is also particularly advantageous for plastic film-based substrates with and without a pressure-receiving layer.

The different subregions of the optically non-variable ink layer can also be applied in principle with virtually all common printing processes. Preferably, however, the offset printing method is used, wherein the application of the color layer in the wet-offset, dry-offset and very particularly preferably in the indirect high-pressure process can take place. Advantageously, the indirect high-pressure process for the color layer and the flexographic printing process for the effect layer are used in a printing process, which then comprises, for example, three partial printing steps (two partial printing steps for the ink layer, one partial printing for the effect layer).

If a laser-sensitive opaque intermediate layer is provided, it is also advantageously printed, with the abovementioned printing methods being able to be used. With particular advantage, all layers of the layer composite are thus produced by printing processes, while the individualization takes place by laser application.

As described, individualization by laser application is preferred in the context of the invention, but in principle a security element according to the invention can also be individualized by a printing process, in particular by ink-jet printing, laser printing or thermal transfer printing. Although it is difficult with these methods to produce interference layers with sufficient uniformity of the layer thickness, it is possible to print on an already existing interference layer as absorption pigments or dyes and thereby make a desired individualization of the security element.

It is also conceivable, in principle, to apply an opaque white layer to a substrate in predetermined areas when the color layer and / or effect layer is not sufficiently opaque, and to subsequently arrange the color layer, optionally the interlayer and the effect layer above it. Such an opaque white layer can be applied to the substrate with relatively high register accuracy by known printing methods, which leads to a high color saturation for the finished security element in the areas with opaque white.

In a preferred embodiment, the security element with the layers according to the invention and individualizing marking is produced on a film, in particular a plastic film, and the security element produced in this way is transferred to the target substrate by means of hot or cold foil application (hot or cold film transfer method) as film strip or foil patch. Of course, it is also conceivable that by means of a suitable method the layers according to the invention are produced on an intermediate carrier and only the layers according to the invention are transferred to the target substrate.

In a further alternative embodiment, it is further provided that the optically non-variable ink layer is arranged on a target substrate and the optically variable effect layer is transferred to the ink layer by means of a suitable transfer process for forming the security element according to the invention. In turn, hot or cold film transfer processes and similar techniques can be used as the transfer process.

It is understood that in the transfer methods described above, an optionally required intermediate layer between the effect layer and the color layer can either be transferred to the target substrate with the entire security element or arranged on the color layer or transferred to the color layer with the effect layer.

Further exemplary embodiments and advantages of the invention are explained below with reference to the figures, in the representation of which a representation true to scale and proportion has been dispensed with in order to increase the clarity.

Show it:

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

2 the visual appearance of the security element of the 1 , in (a) when viewed vertically, and in (b) when viewed obliquely,

3 in (a) and (b) each schematically a cross section of the security element of 2 to explain the layer structure and the realization of the digital information change,

4 to 7 Various advantageous modifications of the security element of 3 .

8th a security element according to a further embodiment of the invention schematically in plan view,

9 a gradient for use in the security element of 8th , and

10 a cross section through the security element of 8th along the line XX.

The invention will now be explained using the example of security elements for banknotes. 1 shows a schematic representation of a banknote 10 with a security element according to the invention 12 , The security element 12 shows an optically variable appearance and is also with a banknote individualizing label 14 provided, depending on the viewing angle, only a partial area is recognizable.

In the individualizing labeling 14 For example, it may be the serial number or a repetition of the denomination 15 to trade the banknote. In the exemplary embodiment, the individualizing marking 14 for the sake of simplicity, it is formed by the number "3456".

To illustrate the only partial recognizability of the label 14 from different viewing directions shows 2 in (a) the visual appearance of the security element 12 when viewed vertically and in (b) at oblique viewing at an angle of z. B. about 45 °.

The marking 14 contains two subareas 16 . 18 , each having a different, fixed color impression. As explained above, the term "solid color impression" designates a color impression which does not change with the viewing angle, while a color impression changing with the viewing angle is referred to as a "variable color impression", the term "variable color impression" also being used, for example. B. brightness or contrast changes.

The marking 14 points in its first section 16 , which is formed in the form of the number sequence "34", the solid color green on, and in its second portion 18 , which is formed in the form of the number sequence "56", the solid color impression magenta.

The environment area 20 the marking 14 shows no solid color impression, but has a color shift effect with a variable color impression, which changes in the embodiment of magenta when viewed perpendicularly to green at oblique viewing.

At the in 2 (a) illustrated vertical viewing agree the solid color impression magenta of the subarea 18 and the variable color impression magenta of the surrounding area 20 match, while the subarea 16 with its solid color impression green in clear contrast to the surrounding area 20 stands. An observer thus sees only the numerical sequence "34" of the green partial area when viewed vertically 16 in front of a uniform magenta background 18 . 20 ,

When viewed obliquely at an angle of 45 °, as in 2 B) illustrated, the solid color impression green of the sub-area 16 and the variable color impression green of the surrounding area 20 while now the subarea 18 with its solid color impression magenta a clearly perceptible contrast to the surrounding area 20 forms. An observer therefore sees only the numerical sequence "56" of the subarea when viewed obliquely 18 in magenta in front of a uniform green background 16 . 20 ,

When going back and forth presents the security element 12 the viewer thus a digital information exchange between the partial information "34" and "56", and thus allows easy verification even by laymen. The viewer tilts the security element 12 fast back and forth, so the entire label "3456" is recognizable due to the afterimage effect of the human eye and the gradual color change of the color shift effect.

The layer structure of the security element 12 and the generation of the digital information exchange will now be described with reference to FIG 3 explained in more detail.

3 (a) schematically shows a cross section of the security element 12 in the field of labeling 14 , The security element 12 has a substrate 30 on, for example, by a foil, but also by the banknote paper of the banknote 10 can be self-educated. On the substrate 30 is initially an optically non-variable color layer 32 imprinted, which is a first subarea 34 with the solid color impression magenta and a second section 36 with the solid color impression contains green.

On the color layer 32 is a laser-sensitive, black intermediate layer 38 and on the interlayer 38 a transparent, optically variable effect layer 40 imprinted against the background of the black interlayer 38 shows the desired color shift effect of magenta when viewed perpendicularly to green when viewed obliquely.

After the production of the said layer sequence were in the sub-areas 16 . 18 the marking 14 the black interlayer 38 and the effect layer 40 ablated locally by laser application and the security element 12 thereby individualized.

3 (a) shows a laser ablation of the layers 38 . 40 However, laser exposure also makes it possible to evaporate layer areas or to convert them into a transparent or other-colored modification.

After the laser individualization the color impression becomes with vertical supervision 42 in the uncovered subareas 16 . 18 in each case by the color impression of the subregions 34 . 36 the color layer 32 determined, so that in the subarea 16 the color impression green (G) and in the partial area 18 the color impression magenta (M) yields. In the environment area 20 shows the optically variable effect layer 40 against the background of the black interlayer 38 when viewed vertically, the color impression magenta (M), so that when viewed vertically, the total in 2 (a) shown visual impression results.

3 (b) illustrates the emergence of the color impression when viewed obliquely 44 , In the uncovered sections 16 . 18 the color impression is unchanged by the solid color impression of the subregions 34 . 36 the color layer 32 determined, so that the subarea 16 as with vertical supervision the color impression green (G) and the partial area 18 the color impression magenta (M) shows. In the environment area 20 creates the optically variable effect layer against the background of the black intermediate layer 38 in an oblique view, the color impression green (G), so that when viewed obliquely in total the in 2 B) shown visual impression results.

A particular advantage of the security element according to the invention in the present case is that the color layer 32 , the intermediate layer 38 and the effect layer 40 On the one hand, all can be generated by printing processes and therefore simple and cost-effective, and on the other hand, the individualization by means of laser application enables a subsequent individualization of the security element. The information to be presented with the identification must therefore not yet be known at the time of manufacture, but can only be generated when the security element is used.

The 4 to 7 show various advantageous modifications of the security element of 3 ,

The security element 12 of the embodiment of 4 corresponds largely to the security element of 3 , however, is the black intermediate layer 38 in the identification sections 16 . 18 not ablated by the laser exposure, but only in a transparent modification 46 been converted. The effect layer 40 can be ablated in this variant by the laser radiation, as in 3 shown, or even persist, as in 4 shown. The latter is particularly useful when the color impressions of the ink layer areas 34 . 36 are relatively bright, because the optically variable effect layer 40 in the labeling areas 16 . 18 then hardly noticed in front of their bright background. It is also conceivable that the effect layer 40 in the area above the identification sections 16 . 18 also only modified.

5 shows a further embodiment of the invention, in which the security element 12 a covering, optically variable effect layer 48 having. Such masking effect layers can be produced, for example, printing inks with multilayer interference layer pigments, as are sold under the name about OVI ^® of SICPA. The marking 14 is in this case through recesses 16 . 18 or alternatively by local transparent modifications of the effect layer produced by the action of laser radiation 48 educated.

In the further embodiment of the 6 is the color layer 50 formed from a laser-sensitive color mixture from which a color component can be removed by the action of laser radiation. Such color mixtures may contain, for example, first colored pigments and laser-sensitive core-shell particles with a second colored pigment, the core-shell particles being provided with an ablation-promoting functional layer. In the non-laser-exposed area 20 Then both color pigments are present and together create a dark background for a transparent, optically variable effect layer 40 , In the laser-exposed area 16 are the laser-sensitive core-shell particles with the second colored pigments from the color layer 50 removed, so that the color impression is determined there only by the first colored pigment.

In the second laser-loaded area 18 may, for example, another first colored pigment in the color layer 50 be present and thereby be generated by laser irradiation another color coding.

Alternatively, the color mixture of the color layer 50 Also contain a plurality of laser-sensitive core-shell particles with a second or third colored pigment, which are removed by different ablationsfördernde functional layers at different strong laser intensity from the mixture. In the non-laser-exposed area 20 Then all three colored pigments are present and create a dark background for the transparent, optically variable effect layer 40 , In the laser-exposed area 16 For example, at low laser intensity, only the laser-sensitive core-shell particle with the third colored pigment is removed, so that the color impression there is determined by a superposition of the first and second colored pigments (first solid color impression). In the laser-exposed area 18 is at high laser intensity in addition the laser-sensitive core-shell particles with the second colored pigment removed, so that the color impression there is determined only by the first colored pigment (second solid color impression). Again, with a suitable choice of colored pigments, the desired color impressions in the first and second sub-range 16 . 18 be generated the marking.

Another variant of the invention is in 7 shown. In this embodiment, the color layer is 52 from a layer 54 a non-laser-sensitive fixed color and a layer applied over it 56 formed, in addition to first colored pigments and laser-sensitive core-shell particles containing a second colored pigment, wherein the core-shell particles are provided with an ablation-promoting functional layer. In the laser-exposed area 16 the laser-sensitive core-shell particles are removed with the second colored pigment, so that the color impression is determined there by the first colored pigment (first solid color impression). In the laser-exposed area 18 is at high laser intensity the entire layer 56 ablated, so that the color impression there by the underlying fixed color layer 54 is given (second solid color impression).

8th shows a security element 60 according to a further embodiment of the invention, wherein the marking 62 in the form of the lettering "50 Euro" has a gradient with smooth transitions. For example, the color impression of the marking 62 Change slowly from green to magenta from top to bottom. It should be emphasized that this color is not a variable color impression, since the color impression at each point of the course when tilting the security element 60 remains unchanged. Rather, the fixed color impression itself changes quasi-continuously from the upper edge to the lower edge of the marking 62 ,

In the exemplary embodiment, this quasi-continuous color gradient is produced with the aid of only two colors (green and magenta) by the successive change of the area fraction of the colors in adjacent color stripes. 9 shows a gradient 70 with a variety of green color stripes 72 and magenta colored stripes 74 , which are arranged in a one-dimensional grid with grid spacing d. Within each raster d, the area fraction g of the green color stripes increases 72 from top to bottom from 100% to 0%. Accordingly, the area ratio m = 100% -g of the magenta color stripes 74 from top to bottom from 0% to 100%. If the grid spacing d is chosen to be small enough, the result is an infinitely variable color gradient for the eye 70 from green to magenta. In practice, a few raster periods, for example 6, 8 or 10 raster grids, are usually sufficient to produce a soft color gradient for the eye.

10 now shows a cross section through the security element 60 along the line XX of 8th , As in 10 shown is on the substrate 80 a color layer 82 imprinted in the field of labeling 62 the color gradient 70 of the 9 contains. The color impression changes from the first section 84 to the second subarea 86 quasi-continuous from the solid color impression magenta to the solid color impression green.

On the color layer 82 is a laser-sensitive, black intermediate layer 38 and on the interlayer 38 a transparent optically variable effect layer 40 imprinted against the background of the black interlayer 38 has a color shift effect of magenta when viewed perpendicular to green at oblique viewing. After the production of the mentioned layer sequence, the black intermediate layer became by laser application 38 and the effect layer 40 in the form of the lettering "50 Euro" locally ablated and the security element 60 thereby with the marking 62 Mistake.

When viewed vertically, the effect layer appears 40 in the surrounding area 20 the marking against the background of the black interlayer 38 with color impression magenta and thus with the same color impression as the lower part 62-U the marking 62 , From the label 62 Therefore, only the middle and upper part are visible when viewed vertically.

When tilting the security element 60 in the direction of the arrow 64 the color impression of the effect layer changes 40 in the surrounding area 20 first to a mixed color magenta / green, and thus to the same color impression, the middle part 62-M the marking shows. When tapping further, the color impression of the effect layer changes 40 then to green, so the same color impression, the upper part 62-O the marking shows.

When tilting in the direction of the arrow 64 Thus, first the middle and then the upper part of the marking disappears 62 due to the lack of contrast to the surrounding area 20 for the viewer, while the lower, magenta part 62-U becomes visible. In the case of rapid reciprocation, all parts of the marking are due to the inertia of the human eye 62 recognizable.

That in the 8th to 10 shown and explained above security element 60 can also be considered as a security element having a plurality of sub-areas each having a fixed color impression in a specific sub-area, as required by the invention.

LIST OF REFERENCE NUMBERS

10

bill

12

security element

14

Labelling

15

Denomination

16, 18

subregions

20

surrounding area

30

substratum

32

optically non-variable color layer

34, 36

subregions

38

interlayer

40

transparent optically variable effect layer

42

vertical supervision

44

weird contemplation

46

transparent modification

48

covering optically variable effect layer

50

coat of paint

52

coat of paint

54

non-laser-sensitive fixed color

56

layer

60

security element

62

Labelling

62-O, 62-M, 62-U

marking parts

64

tilt direction

70

color gradient

72

green color stripes

74

magenta color stripes

80

substratum

82

coat of paint

84, 86

subregions

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2005/108110 A1 [0014, 0015]
• DE 102008049512 A1 [0014, 0015, 0015]
• DE 102006008247 [0014, 0015]

Claims (20)

Security element for hedging valuables, with An optically variable effect layer which gives different color impressions at different viewing angles, - An optically non-variable color layer which is covered at least in a coverage area of the effect layer, and there contains at least a first portion having a first solid color impression and a second portion having a different second solid color impression, and An individualizing marking generated at least in the overlapping area of the effect layer and the color layer, which in each case shows the first or second fixed color impression in a partial area, - Wherein the partial areas of the color layer and the effect layer are coordinated so that the variable color impression of the effect layer corresponds to the first solid color impression at a predetermined first viewing angle. A security element according to claim 1, characterized in that the subregions of the color layer and the effect layer are matched to one another such that the variable color impression of the effect layer corresponds to the second fixed color impression at a predetermined second viewing angle. A security element according to claim 1 or 2, characterized in that the effect layer is opaque or semitransparent and the marking is formed by recesses and / or by local, generated by the action of laser radiation, transparent modifications of the effect layer. A security element according to claim 1 or 2, characterized in that the effect layer is substantially transparent, that between the effect layer and the color layer, a laser-sensitive opaque intermediate layer is arranged, and that the marking is formed by recesses or local transparent modifications of the intermediate layer by Influence of laser radiation are generated. A security element according to at least one of claims 1 to 2, characterized in that the effect layer is substantially transparent, and that the color layer comprises at least one laser-sensitive color mixture and the marking is formed by local color changes in the laser-sensitive color mixture produced by the action of laser radiation are. Security element according to at least one of claims 1 to 5, characterized in that the color layer shows a color gradient between the first and second solid color impression. A security element according to claim 6, characterized in that the color gradient is generated by a multiplicity of juxtaposed first and second color elements, in particular color stripes or raster points, which respectively show the first and second solid color impression, and their area proportions spatially vary by a quasi-continuous color transition from first to produce the second color impression. A security element according to at least one of claims 1 to 7, characterized in that the color layer and / or the effect layer contains a feature substance, in particular a magnetic, electrically conductive, luminescent or infrared-absorbing feature substance. Security element according to at least one of claims 1 to 8, characterized in that the effect layer contains single or multilayer interference pigments or cholesteric liquid crystal pigments. Security element according to at least one of claims 1 to 9, characterized in that the individualizing marking is continued outside the covering area, in particular by a local change of a standard color or a local change, such as foaming or blackening of a substrate. Security element according to at least one of claims 1 to 10, characterized in that the individualizing marking is executed rasterized and preferably represents a screened grayscale image or a screened color halftone image. A security element according to at least one of claims 1 to 11, characterized in that the color layer and the effect layer are coated at least in the overlapping area with a lacquer layer which compensates for a different matt or gloss effect in the region of the marking. A security element according to at least one of claims 1 to 12, characterized in that the partial regions of the marking with the first and second color impression represent information that is related to one another or complementary to one another. Security element according to at least one of claims 1 to 13, characterized in that the security element comprises a substrate, on which the color layer and the effect layer are arranged in this order. Data carrier, in particular value document, such as banknote, identity card and the like, with a security element according to one of claims 1 to 14. A data carrier according to claim 15, characterized in that the individualizing marking is continued over the security element in register with the data carrier. Method for producing a security element for securing valuables, in which A substrate is provided, An optically non-variable ink layer is applied which, in an overlapping region, contains at least a first partial region with a first solid color impression and a second partial region with a different second solid color impression, An optically variable effect layer is applied which imparts different color impressions at different viewing angles, and which covers the optically non-variable ink layer in the overlapping area, - Wherein the portions of the ink layer and the effect layer are coordinated so that the variable color impression of the effect layer at a predetermined first viewing angle corresponds to the first solid color impression, and - At least in the coverage area of the effect layer and color layer an individualizing marking is generated, each showing the first or second fixed color impression in a sub-area. A method according to claim 17, characterized in that the individualizing marking by laser exposure, in particular with an infrared laser, such as a CO ₂ laser, Nd: YAG laser or Nd: YVO ₄ laser is generated. A method according to claim 17 or 18, characterized in that the individualizing marking is produced after the production of the layer sequence of substrate, ink layer and effect layer in a separate manufacturing step. Method according to at least one of claims 17 to 19, characterized in that the color layer and / or the effect layer, preferably two layers are applied in a printing process.

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