EP1986867B1 - Security element with an optically variable structure - Google Patents

Abstract

The invention relates to a security element with an optically variable structure having an embossing structure with linear embossing elements and a coating, wherein the embossing structure and the coating are arranged such that at least parts of the coating can be seen in full when viewing at right angles, but are covered when viewing at an oblique angle. The fact that substantially the entire coating is formed by non-linear base elements which are characterized by the parameters outline, size, colour and orientation and are combined with the embossing structure such that, when the viewing direction is changed, different information becomes visible, can be used to increase the security against forgery of the security element. The invention further relates to a method for producing such a security element, a data carrier having such a security element and the use of such a security element or data carrier for product security.

Description

The invention relates to a security element with an optically variable structure, which has an embossed structure with line-shaped embossing elements and a coating, wherein the embossing structure and the coating are arranged so that at least parts of the coating are completely visible when viewed vertically, but hidden by oblique view. The invention further relates to a method for producing such a security element, a data carrier with such a security element and the use of such a security element or data carrier for product security.

To protect against counterfeiting, especially with color copiers or other reproduction methods, data carriers such as banknotes, securities, credit or identity cards, passports, certificates and the like, labels, packaging or other elements for product protection are equipped with optically variable security elements. The protection against counterfeiting is based on the fact that the visually simple and clearly recognizable optically variable effect is not or only insufficiently reproduced by the abovementioned reproduction devices.

This is for example from the CA 1019 012 a bill known which is provided in a partial area of its surface with a parallel line printing pattern. To generate the optically variable effect, a line structure is additionally embossed in the data carrier in the region of this line print pattern so that flanks arise that are only visible at certain viewing angles. By targeted arrangement of the line pattern on flanks of the same orientation, these lines are visible when viewed obliquely the flanks provided with the lines, with oblique view of the back flanks line pattern is not recognizable. If phase jumps are present in the line grid or in the embossing grid in subregions of the embossed surface, then information can be displayed that is recognizable either only from the first oblique viewing angle or only from the second viewing angle.

Although such an optically variable security element shows a relatively sharp tilting effect to the observer, the constant line spacing parallel line pressure patterns nowadays can be readjusted with some effort by means of modern reproduction techniques. Another disadvantage is that the in the CA 10 19 012 line patterns described do not allow tilting effects with detailed and elaborately designed image motifs as a coating.

From the WO 2004/022355 A2 a security element with an optically variable structure is known, wherein the optically variable structure has an embossed structure with line-shaped embossing elements and a coating. The embossed structure and the coating are arranged so that at least parts of the coating are completely visible when viewed perpendicularly, but are concealed when obliquely viewed.

Furthermore, from the DE 10 2005 011 612 A1 a security element with an optically variable structure is known, which has an embossed structure and a coating, wherein the embossing pattern is formed from non-linear embossing elements.

The invention has for its object to provide a security element of the type mentioned above, which avoids the disadvantages of the known generic security elements and an increased level of security against counterfeiting offers. In addition, a data carrier with such a security element and a method for producing such a security element should be specified.

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

The optically variable structure of the security element according to the invention consists of a coating which is substantially completely formed from nonlinear basic elements, and an embossed structure superimposed on this coating. The embossing structure has line-shaped embossing elements, which with the coating of non-linear basic elements are combined so that when changing the viewing direction different information is visible. The nonlinear basic elements are characterized by the parameters outline shape, size, color and orientation and thus combined with the embossed structure that results in the shading effect according to the invention. With regard to the line-shaped embossing elements, the nonlinear basic elements are thus arranged in such a way that a certain information results for a viewer in a view of the security element, which changes when the viewing direction changes.

In the following, a line is understood to be a combination of two points, according to the definition given in Paperback of Mathematics, Bronstein, Semendjajew, 25th edition. Of course, according to this definition in addition to a straight connection and a non-linear, d. H. curved, curved or spiral connection of two points in two- or three-dimensional space includes.

In terms of the present invention, this means that linear embossing elements are understood to mean all three-dimensional elements whose projections form a line in the plane of the optically variable element in accordance with the above definition.

The linear embossing elements are generally characterized by four flanks, wherein these flanks have dimensions which enable the shadowing effect according to the invention. D. h., The flanks must be dimensioned so that for the viewer who looks at such a flank, a lying behind this edge information is at least partially hidden or shadowed.

Non-linear basic elements are understood below to mean all elements of the two-dimensional and three-dimensional space whose outline shape is selected such that they are not linear elements in the sense of the above definition of a line. Accordingly, the nonlinear basic elements of the present application are derived from a single planar point and not from a surface connection of two points (line). In general, the non-basic elements can thus be characterized as compact, not elongated elements.

By using non-linear primitives of any shape, size, color and orientation, the coating of the optically variable structure can be so elaborate and detailed that a forgery is currently practically impossible. The protection against counterfeiting is also increased according to the invention in that essentially the entire coating is formed from nonlinear basic elements. A potential counterfeiter would not only have to adjust individual areas, but the entire coating with extreme accuracy, which is currently practically impossible.

In addition to increasing the security against counterfeiting through the use of the embossed coating according to the invention, the choice with regard to the motifs and geometric patterns that are eligible for the coating and the freedom of design for the motifs and patterns are advantageously increased substantially, resulting in a significantly more impressive effect when the coating is suitably embossed and give visually appealing tilting effects to the viewer. As a result, the authenticity of a security element according to the invention is also easily detectable by the "man or woman on the street". A fake security element can be readily recognized by the fact that the dramatic optical tilting effect inherent in the authentic optically variable structure can not or only to a very limited extent be observed for a very elaborately designed coating.

By using the nonlinear basic elements according to the invention, it is advantageously also possible, in connection with the generic security elements, to realize hitherto unknown tilting effects with image motifs or geometric patterns shown in true colors. Finally, another advantage of the invention is that the superimposition of primitives of different color allows viewing direction dependent mixed color effects.

The basic elements according to the invention are characterized on the one hand by the parameter outline shape. There are all outlines conceivable that are not linear in the sense of the above definition. Although the outline of the basic elements can be varied within a very wide range, such basic elements are preferred which have a round, oval or polygonal limited outline shape. Polygonal limited in the context of the present invention are all basic elements that are a polygon or polygon in the mathematical sense. Conceptually, polygons are captured in two- or three-dimensional space. Accordingly, polygons, starting with triangles to polygons with a large number of corners, conceivable. In the polygons, various squares, such as parallelograms, squares, rectangles, diamonds and trapezoids, are particularly preferred. Of course, the non-linear basic elements may also have an outline, the z. B. round or oval, is limited in other areas polygonal.

In addition to these outline shapes known from geometry, it is also preferred that the line-shaped basic elements have an outline shape that is determined by a symbol, geometric pattern and / or alphanumeric character. It can be used as symbols all non-linear primitives that are accessible to the methods used for the application of the coating. In this case, for example, mathematical symbols, such as the integral or root characters, or to think of the well-known cross or double cross symbol. In addition, characters, especially alphanumeric characters, of all known fonts may be used, although characters from the standard Latin and Greek fonts are particularly preferred. In addition, the outline of a basic element according to the invention by a geometric pattern, for. As the outline of a snowflake or a guilloche pattern be determined.

The nonlinear basic elements characterized by a certain contour shape can expediently have a filling, which is preferably embodied essentially over the whole area. Of course, it is also conceivable that the filling is rasterized, z. B. in the form of a dot matrix, or that the basic element is determined only by a line defining the outline contour and thus has no filling. In this case, in the unfilled inner regions of the primitives, the color of the underlying layer or layers may be recognized.

The size of a nonlinear basic element according to the invention is understood to mean its dimension in one or more directions. Although it may be useful for certain uses in the product fuse area, primitives with a dimension in Provide the order of a few millimeters, it is particularly preferred if the non-linear base elements have a dimension of 10 .mu.m to 500 .mu.m, in particular from 20 .mu.m to 250 .mu.m. It goes without saying that the small size of the counterfeit protection of the claimed security elements with optically variable structure is increased. Accordingly, in particular provide coatings with a dimension of the basic elements of z. B. 30 microns a very large protection against counterfeiting. At the same time, of course, the dimension of the basic elements should be provided so that this enables the production of high-quality security elements according to the invention.

In contrast to the example of the CA 1019 012 In the case of known coatings with line-printing patterns in which the dimension of the lines in the longitudinal direction is considerably greater than the dimension of the lines in the transverse direction, the nonlinear basic elements according to the invention preferably have an outline shape in which the dimension in no direction is more than four times the dimension in one of the dimensions other directions of the primitive.

It has been found that particularly impressive tilting effects of the optically variable structures can be achieved with simultaneously high freedom of design for the coating according to the invention if the basic elements according to the invention have a shape which is not too different from the outline of a circle, triangle or square. So a compact element is different. In these bodies, the dimension in no direction is more than about twice a dimension in one of the other directions.

The coatings from the non-linear basic elements according to the invention may be a printing layer, in particular an offset, stitch, screen, flexographic, xerographic, inkjet or thermographic printing layer. Each of the printed layers mentioned has certain properties, which are known per se to the person skilled in the art, depending on the method used for them. The choice of a particular print layer will therefore depend on the one hand on the intended use of color, the desired embossed structure, resolution, the intended image motif, etc.

Moreover, it is preferred if the coating of nonlinear basic elements is a layer which is introduced by a laser printer or by the action of laser radiation of a laser. Here, depending on the material used for the substrate of the optically variable structure, CO ₂ lasers, Nd: YAG lasers or other types of lasers in the wavelength range from ultraviolet (UV) to far infrared (IR) can be used as radiation sources, the lasers often also work with frequency doubling, tripling or even greater frequency multiplication. However, laser sources in the near IR are preferably used, since this wavelength range fits well with the absorption properties of the materials provided for the optically variable structures. Since the spot size of the laser radiation can vary from a few micrometers to a few millimeters depending on the application, the basic elements according to the invention can advantageously be produced by the use of laser radiation. The continuous power of the laser used for this purpose is usually between a few watts and a few hundred watts.

The coating according to the invention can basically be formed from nonlinear basic elements of any arrangement. Next a completely random arrangement is thus z. As well as the arrangement - possible in the form of a fractal pattern. However, it is particularly preferred if at least a part of the non-linear base elements is arranged in a preferably periodic grid. By means of a grid-shaped arrangement of the basic elements, preferred directions of the coating are defined which, when combined with a suitable embossing structure, lead to particularly impressive tilting effects. Although it is basically possible that only a part of the non-linear base elements in the form of a grid and the other part is not arranged in a grid, it is particularly useful if all the basic elements forming the coating in the form of a grid, in particular periodic grid, are arranged.

Regardless of whether the primitives are arranged randomly or in a grid, primitives of different colors may overlap and create a blend color in the overlap areas, and the arrangement of the blends in the overlap areas may in turn be a safety feature of the coating.

According to a preferred embodiment, it is provided that in each case at least two non-linear basic elements of different color are arranged in the form of color primitives. The choice of colors and the type of the basic elements of a color primitive is basically arbitrary, but preferred are colors of a primary color system. Through the use of color basic elements, complex and detailed motifs and geometric patterns can be displayed.

The arrangement of the color primitives can in turn be completely random, in the form of a fractal pattern or in a combination of these two arrangement options. However, it is particularly preferred if at least a part of the color primitives is arranged in a particular periodic grid. Such an arrangement is particularly suitable for the representation of colored images and similar subjects. Of course, it is also conceivable that a larger number of color primitives is arranged in a grid and the coating has at the same time random or likewise grid-shaped, non-linear basic elements.

Although the basic elements or color primitives can be arranged in a grid with varying screen ruling, it is particularly expedient if the grid width of the grid is constant for a part or the entire coating. The resulting regular arrangement defines one or more preferred directions in the plane of the coating and, in combination with a correspondingly arranged embossing structure, opens up particularly striking tilting effects for the viewer.

The coating of non-linear primitives or color primitives formed therefrom may contain primitives of any color. But especially preferred are basic elements in the colors of a basic color system. In addition, coatings are claimed that have color primitives with non-linear primitives in the colors of a primary color system. In this case, all primary color systems can be used, which enable the application of a coating for the optically variable structure with the printing techniques already described. However, the primary color systems RGB (red, green, blue), CMY (cyan, magenta, yellow) and CMYK (cyan, magenta, yellow, key (black)) are particularly preferred.

In addition, it is particularly expedient if the optically variable structure has a multiplicity of color primitives which, when viewed vertically, represent a multicolored image motif and / or geometric pattern whose visual impression varies when the viewing angle is changed. The color primitives representing the image motif or pattern may include non-linear primitives of any color or elements in the colors of a primitive color system. As already mentioned, it is possible by means of a suitable embossing of the coating according to the invention to produce elaborate and highly detailed image motifs which are substantially completely visible in plan view but only partially visible when the viewing angle changes due to the shadowing effect.

In a special embodiment, the color primitives correspond to the pixels of the image motif and / or geometric pattern to which certain color components of a color system are assigned. The basic color elements have non-linear basic elements with colored areas in the colors of the color system, the size of the colored areas of the nonlinear basic elements corresponding to the respective color proportion of the picture elements. The color impression of a color primitive thus results for the viewer from the size of the areas occupied by the respective colors. The surfaces can adjoin one another directly or also maintain a certain distance from one another, so that the color impression of the basic color element is ultimately also determined by the color of the light reflected from the background. Thus, according to this specific embodiment, it is possible to display image motifs and geometric patterns in true colors, wherein at the same time the number of pixels of the image motif or pattern corresponds to the number of color primitives. It should be noted that in supervision, the true color of a color primitive as a mixed color of the non-linear primitives forming the color primitive, provided that the dimensions of the colored areas are below the visual resolution of the observer.

According to a further advantageous embodiment of the security element, it is provided that at least two rasters of nonlinear basic elements of each color form an image motif and / or geometric pattern. The arrangement of the raster defines areas in which the non-linear basic elements of different rasters overlap and produce a mixed color in these areas. In order to produce a mixed color that is as defined as possible in the overlapping area, nonlinear basic elements with a well-defined outline shape and a full-surface filling to form the grid are particularly preferred. Of course, the rasters may contain primitives in the colors of a primary color system, whereby the mixed colors produced in the overlap regions are again well-defined secondary colors of a subtractive color mixture. Since the screens used generally do not cover the substrate material over the entire area, a light reflection occurs in the uncovered areas of the substrate. The reflected light and the overlapping areas of subtractive color mixing ultimately result in an additive (autotypical) color mixture perceived by the observer.

It is furthermore particularly preferred if the regions of overlapping basic elements correspond to the image points of the image motif and / or geometric pattern to which certain colors of a color system are assigned; and the mixed color of the regions of overlapping primitives corresponds to the respective color of the pixels, such that the color impression of the image motif and / or of the geometrical pattern varies as the viewing angle changes. In this case, so a pixel of the subject or Pattern represented by a mixed color produced by means of subtractive color mixing. Depending on the degree of coverage of the substrate by the overlapping regions of the raster, the viewer ultimately also to some extent obtains additive color mixing by the light reflected by the substrate.

If the non-linear base elements or color base elements are arranged in the form of a grid, at least one preferred direction in the plane of the coating is defined by such a regular arrangement of the base or color base elements. It is particularly preferred for the line-shaped embossing elements to be arranged at least in regions in the direction of the at least one preferred direction, so that the visual impression varies depending on the viewing direction as a result of a viewing of the regions provided with embossed structures in a direction perpendicular to the at least one preferred direction. It has been shown that with an arrangement of the embossing elements in a preferred direction of the perceptible to the viewer tilt effect is particularly pronounced when changing the viewing angle. In addition, the tilting effect will be particularly impressive if different areas of the coating are provided with embossing elements, which are each arranged in a preferred direction. The preferred direction itself can be caused by the outline shape and / or the arrangement of the basic elements or color primitives in the grid. Accordingly, a preferred direction can be determined by the arrangement and at the same time by the outline contour of the grid forming basic elements.

The optically variable structure may have additional information that arises due to variation of the coating and / or the embossed structure. The additional information may be from one or more viewing directions be recognizable. It is also possible for the additional information to be transferred into a second, third, etc. additional information depending on the viewing angle.

The additional information can, for example, by a variation of the shape, color and / or the arrangement of non-linear primitives, such as offset, change the screen ruling, omission, reflection of individual or several non-linear primitives arise. Also, the additional information can be an optically variable element individualizing information in the coating, such. As alphanumeric characters or barcodes have.

Although the inventive optically variable structure of the security elements may include line-shaped embossing elements of any arrangement, it is particularly preferred if the embossing elements are arranged in the form of an embossing grid with a screen pitch. The grid width of the embossed structure can correspond to the grid width of the coating grid. On the other hand, if the grid widths of the coating and the embossed structure are not identical but shifted by a certain value, interesting viewing direction-dependent beat effects result.

Advantageously, the additional information also by a variation of the shape, size, height and / or the arrangement of the line-shaped embossing elements, such as offset, change the screen width, omission of individual or several line-shaped embossing elements arise. The additional information by varying the embossed structure is reinforced by a simultaneous variation of the coating.

In a further advantageous embodiment, it is provided that the optically variable structure is subdivided into partial regions in which different partial embossing structures and / or partial coatings are arranged. If the line-shaped embossing elements of the embossed structure or the non-linear base elements are arranged in the form of a grid with a screen ruling, an expedient embodiment results from the fact that the subareas structures or sub-coatings in at least two adjoining sub-areas by a fraction, in particular one third of the screen, are arranged offset. In addition, parts of the partial embossing structures may have an unembossed edge contour for better visibility.

In connection with this matrix-like arrangement of the partial embossing structures as well as the generation of additional information in the area of the embossed structures or the coating is here expressly to WO 97/17211 as well as the WO 02/20280 A1 Referenced.

The optically variable structure according to the invention forms a security element which is difficult to imitate and can be arranged directly on any data carriers. However, the optically variable structure can also be part of a security element which, in addition to the optically variable structure, has further security features.

The security element may have, for example in the region of the optically variable structure, a further color layer, which is preferably translucent and which is arranged congruently with the raised regions of the embossed structure. Again, various embodiments are possible. For example, some are already in the WO 2004/022355 A2 described, which is also expressly referred to in this context.

According to a further embodiment, the security element can have further layers and authenticity features, such. Example, a metallic layer, a metal effect layer, an additional translucent, optically variable layer or a film element. Such layers and elements can be superimposed or underlaid optically variable structures. Of course, the coating combined with the line-shaped embossing elements can also be such a metallic layer, a metallic effect layer or an optically variable layer.

Finally, it is also possible to equip the coating or the printing inks used for the production of the basic elements and color primitives and / or the ink layer arranged congruently with the raised regions of the embossed structure at least partially with machine-readable properties. For this come z. B. magnetic, electrically conductive, luminescent additives into consideration. Also in a certain wavelength range, preferably in the UV or IR range, absorbing additives can be used advantageously.

The optically variable structure according to the invention or the security element according to the invention is preferably applied to data carriers, such as security and value documents, such as banknotes, stocks, bonds, certificates, vouchers, credit or identity cards, passports or the like. The data carriers are equipped in this way with an easily recognizable even to lay security element to increase the security against counterfeiting. However, the optically variable structure or the security element according to the invention can also be very advantageous in the field of Product protection can be used. In this case, the optically variable structure or the security element can be applied to corresponding labels or packaging or the product itself.

If paper is used as the data carrier material, in particular cotton vellum papers, paper-like materials consisting of plastic films, paper coated or laminated with plastic films or multilayer composite materials are suitable.

For the production of the security element or the optically variable structure according to the invention, an arbitrary substrate is preferably first provided with the coating of nonlinear basic elements, and subsequently the embossed structure is produced in register with this coating. In principle, however, it is also possible to provide the method steps in reverse order. The coating is preferably printed or transferred by thermal transfer to the substrate. The coating can in any printing process, such as in planographic printing, z. B. in the offset process, in high pressure, z. B. in letterpress or flexographic printing, screen printing, gravure, z. As in gravure or gravure printing, or be produced in a thermography process. In addition, the coating can preferably also be produced by a laser printer or by the action of laser radiation.

For the production of the embossed structure also come any method into consideration. Preferably, the embossed structure is produced by means of an embossing tool, which may be, for example, a gravure printing plate. In this case, the embossing is produced by means of a non-ink-bearing intaglio printing plate as blind embossing. According to a particular embodiment, the Embossed structure, however, also be produced in the color-guiding intaglio printing. This manufacturing variant is particularly suitable for the embodiments in which congruent to the embossed structure, a further color layer is provided.

For the production of the embossing tool, for example, a plate surface is milled with an engraving stylus or a laser. As the plate surface, any material such as copper, brass, steel, nickel or the like can be used. The engraving stylus used for the milling preferably has a flank angle of about 40 ° and a rounded tip that approximates a spherical segment or sector. The embossing tool can be milled as a single use or even as multiple benefits.

In principle, the order of the two process steps is freely selectable. As a rule, the coating is first applied and then embossed. Thus, the relief height and shape of the embossing of further influences, which occur for example in a subsequent printing process, spared.

However, the alternative of embossing first and then applying the coating offers the advantage of higher color brilliance and sharper contoured imprinting. This effect stems from the fact that during the embossing process the substrate is calendered at the same time and thus obtains a smoother, less absorbent surface.

In addition, the application of the coating before embossing has the advantage that the coating exclusively on the flanks of the embossing elements or only in the zenith / amplitudes of the embossing elements can be arranged. As a result, particularly impressive shading effects can be achieved. In contrast to the ink-conducting intaglio printing, in which the embossing and the application of the coating takes place simultaneously and the coating can be arranged exclusively in the region of the zenith / amplitudes of the embossing elements, the separation of the process steps embossing and application of the coating opens up a much greater degree of design freedom , In particular, a process control, in which the coating is first arranged on the substrate and then the embossed structure is produced with a high registration accuracy, allows the already mentioned, selective arrangement of the coating exclusively on the flanks of the embossing elements, while the zenith / amplitudes of the embossing elements no coating exhibit. With respect to the exclusive arrangement of the coating in the zeniths / amplitudes or flanks of the embossing elements, the disclosure content of WO 97/17211 included in the present application. In addition, further details and advantages for the selective arrangement of the coating on the flanks or the zeniths / amplitudes can also be taken from the description of the figures of the present application.

The advantages of the invention will be explained with reference to the following examples and additional figures. The described individual features and embodiments described below are inventive in their own right, but are also inventive in combination. The examples illustrate preferred embodiments, to which, however, the invention should not be limited in any way. The proportions shown in the figures do not correspond to the conditions present in reality and serve only to improve the clarity.

Fig.1

einen erfindungsgemäßen Datenträger,

Fig. 2

einen Schnitt entlang der Linie A-A aus Fig.1,

Fig. 3

eine erste erfindungsgemäße Beschichtung in Aufsicht,

Fig. 4

eine zweite erfindungsgemäße Beschichtung in Aufsicht,

Fig. 5

eine dritte erfindungsgemäße Beschichtung in Aufsicht

Fig. 6

eine vierte erfindungsgemäße Beschichtung in Aufsicht,

Fig. 7

eine fünfte erfindungsgemäße Beschichtung in Aufsicht,

Fig. 8

eine sechste erfindungsgemäße Beschichtung in Aufsicht, die eine Variante der Beschichtung der Fig. 7 ist,

Fig. 9

eine Prägestruktur mit linienförmigen Prägelementen in Auf- sicht,

Fig.10

eine weitere erfindungsgemäße Beschichtung mit in Form eines Rasters angeordneten nicht linienförmigen Grundelementen,

Fig.11

eine perspektivische Ansicht einer erfindungsgemäßen optisch variablen Struktur, die aus der in Fig. 9 und Fig. 10 dar- gestellten Prägestruktur bzw. Beschichtung gebildet wird,

Fig.12

eine weitere Prägestruktur mit nicht linienförmigen Präge- elementen,

Fig.13

eine weitere erfindungsgemäße Beschichtung mit in Form eines Rasters angeordneten, nicht linienförmigen Grundelementen,

Fig. 14

eine perspektivische Ansicht einer weiteren erfindungsgemä- ßen optisch variablen Struktur, die aus der in Fig.12 und Fig. 13 dargestellten Prägestruktur bzw. Beschichtung gebildet wird,

Fig. 15

eine weitere erfindungsgemäße Beschichtung mit drei ver- schiedenen Typen nicht linienförmiger Grundelemente, die in Form eines Rasters angeordnet sind,

Fig. 16

die erfindungsgemäße Beschichtung aus Fig. 15 mit für drei Bereiche der Beschichtung eingezeichneten Vorzugsrichtun- gen,

Fig.17a

eine weitere erfindungsgemäße Beschichtung mit rasterförmig angeordneten, nicht linienförmigen Grundelementen,

Fig.17b

die Beschichtung aus Fig. 17a mit drei eingezeichneten Vor- zugsrichtungen und dazu korrespondierenden, schematisch dargestellten Prägestrukturen,

Fig. 18a

eine weitere erfindungsgemäße Beschichtung mit rasterförmig angeordneten, nicht linienförmigen Grundelementen,

Fig. 18b

drei sich aus der rasterförmigen Anordnung gemäß Fig.18a er- gebende Vorzugsrichtungen,

Fig. 18c

eine weitere erfindungsgemäße Beschichtung mit rasterförmig angeordneten Farbgrundelementen,

Fig.18d

drei sich aus der rasterförmigen Anordnung gemäß Fig. 18c ergebende Vorzugsrichtungen,

Fig. 19

eine weitere erfindungsgemäße Beschichtung mit rasterförmig angeordneten Farbgrundelementen, wobei die Beschichtung eine Zusatzinformation aufweist,

Fig. 20

einen Ausschnitt aus einem in Fig.1 dargestellten Bildmotiv in Schwarz-Weiß-Darstellung,

Fig. 21

den Ausschnitt gemäß Fig. 20 in Form einer erfindungsgemä- ßen Beschichtung mit rasterförmig angeordneten, nicht linien- förmigen Grundelementen,

Fig. 22

den Ausschnitt aus Fig. 20 in Form einer weiteren erfindungs- gemäßen Beschichtung,

Fig. 23

eine weitere erfindungsgemäße Beschichtung mit in Form eines Rasters angeordneten Farbgrundelementen,

Fig. 24

die Beschichtung der Fig. 23 mit zwei sich aus dem Raster ergebenden Vorzugsrichtungen und entlang in diesen Vorzugs- richtungen angeordneten Prägeelementen in einer Aufsicht,

Fig. 25

einen Ausschnitt aus Fig. 20 mit einer Vorzugsrichtung für die Anordnung der linienförmigen Prägeelemente,

Fig. 26

ein weiteres Bildmotiv mit mehreren Vorzugsrichtungen für die Anordnung der linienförmigen Prägeelemente,

Fig. 27

eine weitere Prägestruktur mit linienförmigen Prägeelementen,

Fig. 28

eine weitere erfindungsgemäße Beschichtung mit in Form eines Rasters angeordneten, nicht linienförmigen Grundelementen, wobei sich nicht linienförmige Grundelemente verschiedener Raster bereichsweise überlappen,

Fig. 29a

eine weitere erfindungsgemäße Beschichtung mit sich überlap- penden Grundelementen verschiedener Farben und drei Vor- zugsrichtungen der Beschichtung,

Fig. 29b

die erfindungsgemäße Beschichtung aus Fig. 29a mit einer in der Beschichtung angeordneten Zusatzinformation,

Fig. 29c

die erfindungsgemäße Beschichtung aus Fig. 29a mit einer in der Beschichtung angeordneten weiteren Zusatzinformation,

Fig. 30

eine weitere erfindungsgemäße Beschichtung mit einer einge- zeichneten Richtung, die nicht einer Vorzugsrichtung der Be- schichtung entspricht,

Fig. 31

Querschnitt durch eine Prägestruktur mit einer Zusatzinforma- tion,

Fig. 32

eine weitere Prägestruktur im Querschnitt mit einer anderen Zusatzinformation,

Fig. 33

eine weitere Prägestruktur im Querschnitt mit Prägeelementen, die in einem Raster großer Rasterweite angeordnet sind,

Fig. 34a-34p

Querschnitte durch verschiedene linienförmige Prägeelemente,

Fig. 35a

einen erfindungsgemäßen Datenträger im Querschnitt vor der Verprägung,

Fig. 35b

einen erfindungsgemäßen Datenträger im Querschnitt nach der Verprägung,

Fig. 36a

einen weiteren erfindungsgemäßen Datenträger im Querschnitt vor der Verprägung,

Fig. 36b

den weiteren erfindungsgemäßen Datenträger nach der farbführend ausgeführten Verprägung.

In detail, show schematically:

Fig.1

a data carrier according to the invention,

Fig. 2

a section along the line AA Fig.1 .

Fig. 3

a first coating according to the invention in supervision,

Fig. 4

a second coating according to the invention in supervision,

Fig. 5

a third coating according to the invention in plan view

Fig. 6

a fourth coating according to the invention in supervision,

Fig. 7

a fifth coating according to the invention in supervision,

Fig. 8

a sixth coating according to the invention in plan view, which is a variant of the coating of Fig. 7 is

Fig. 9

an embossed structure with linear embossed elements in supervision,

Figure 10

a further coating according to the invention with non-linear basic elements arranged in the form of a grid,

Figure 11

a perspective view of an optically variable structure according to the invention, which consists of the in FIGS. 9 and 10 is formed embossed structure or coating,

Figure 12

another embossed structure with non-linear embossed elements,

Figure 13

a further coating according to the invention, arranged in the form of a grid, with nonlinear basic elements,

Fig. 14

a perspective view of another inventive optically variable structure, which consists of the in Fig. 12 and Fig. 13 formed embossed structure or coating is formed,

Fig. 15

a further coating according to the invention having three different types of nonlinear basic elements which are arranged in the form of a grid,

Fig. 16

the coating of the invention Fig. 15 with preferred directions drawn for three areas of the coating,

Fig.17a

a further coating according to the invention with grid-shaped, non-linear basic elements,

Fig.17b

the coating off Fig. 17a with three marked preferred directions and corresponding, schematically illustrated embossing structures,

Fig. 18a

a further coating according to the invention with grid-shaped, non-linear basic elements,

Fig. 18b

three of the grid-like arrangement according to Fig.18a resulting preferential directions,

Fig. 18c

a further coating according to the invention with grid-shaped color primitives,

Fig.18d

three of the grid-like arrangement according to Fig. 18c resulting preferential directions,

Fig. 19

a further coating according to the invention with grid-shaped color primitives, wherein the coating has additional information,

Fig. 20

a section of a in Fig.1 illustrated picture in black and white,

Fig. 21

the clipping according to Fig. 20 in the form of a coating according to the invention with grid-shaped, non-linear basic elements,

Fig. 22

the cutout Fig. 20 in the form of a further coating according to the invention,

Fig. 23

a further coating according to the invention with color primitives arranged in the form of a grid,

Fig. 24

the coating of the Fig. 23 with two preferred directions resulting from the grid and embossing elements arranged along these preferred directions in a plan view,

Fig. 25

a section from Fig. 20 with a preferred direction for the arrangement of the line-shaped embossing elements,

Fig. 26

Another image motif with several preferred directions for the arrangement of the line-shaped embossing elements,

Fig. 27

another embossed structure with line-shaped embossing elements,

Fig. 28

a further coating according to the invention with non-linear basic elements arranged in the form of a grid, with nonlinear basic elements of different rasters overlapping in regions,

Fig. 29a

a further coating according to the invention with overlapping basic elements of different colors and three preferred directions of the coating,

Fig. 29b

the coating of the invention Fig. 29a with additional information arranged in the coating,

Fig. 29c

the coating of the invention Fig. 29a with a further additional information arranged in the coating,

Fig. 30

a further coating according to the invention with a marked direction which does not correspond to a preferred direction of the coating,

Fig. 31

Cross section through an embossed structure with an additional information,

Fig. 32

a further embossed structure in cross-section with another additional information,

Fig. 33

a further embossed structure in cross-section with embossing elements, which are arranged in a grid of large screen ruling,

Fig. 34a-34p

Cross sections through different line-shaped embossing elements,

Fig. 35a

a data carrier according to the invention in cross section before embossing,

Fig. 35b

a data carrier according to the invention in cross section after embossing,

Fig. 36a

another data carrier according to the invention in cross-section before embossing,

Fig. 36b

the further data carrier according to the invention after the color leading executed embossing.

The Fig.1 shows a data carrier 1 according to the invention in the form of a banknote with an optically variable structure 3, which is placed in the print image area 2 of the data carrier 1 and in the pressure-free area. The optically variable structure 3 is used according to the invention as a so-called human feature, ie as a testable by humans without aids feature, in addition to optionally other features for determining the authenticity of the disk. The provision of such features is particularly useful for banknotes, but also for other monetary documents, such as stocks, checks and the like. Come as a data carrier in the context of the invention also labels, passports or cards into consideration, as they are today z. B. for the identification of persons or goods or to carry out transactions or services.

The optically variable structure 3 can be of different construction, combined with the resulting different effects from different viewing directions. According to a preferred embodiment, the optically variable structure 3 consists of a contrasting to the surface of the data carrier single or multi-colored coating, such as a pattern, image or alphanumeric information, the printing or other means, such as by a transfer process or by the action of laser radiation , is produced. Depending on the design of the coating and embossing structure and their assignment to one another, the effects according to the invention which can be used for checking the authenticity are produced by the embossing structure cooperating with the coating.

All the optically variable structures according to the invention have in common that they and the effects resulting therefrom can not be imitated by the reproduction techniques known today, in particular copiers, since the copiers can reproduce the optically variable structure only from one viewing direction, so that the optically variable Effect is lost. In addition, the imitation will usually fail due to the low resolution of the reproductive devices.

In the following, examples of various preferred embodiments of the invention will be explained with reference to the figures. The illustrations in The figures are highly schematized for better understanding and do not reflect the realities.

The embodiments described in the following examples are reduced to the essential core information for ease of understanding. In practice, much more complex patterns or images in single or multi-color printing can be used as a coating. The same applies to the embossed structures. The information presented in the following examples can also be replaced by arbitrarily complex image or text information. The generation of the coating z. B. as a print usually uses the possibilities of printing technology. Typical dimensions of non-linear basic elements from approx. 10 μm are used. The line-shaped embossing elements that form the embossed structure, as a rule have an embossing height in the range of 10 .mu.m to 250 .mu.m, preferably from 50 .mu.m to 120 .mu.m. The various embodiments are not limited to use in the form described, but can be combined to increase the effects with each other.

Furthermore, in the following examples, only the design and mutual association of the embossed structure and the coating are shown in order to illustrate the optical effects of the optically variable structure according to the invention.

Example 1 (FIGS. 2 to 14 and FIG. 34)

Fig. 2 shows a schematic sectional view along the line AA (see Fig. 1 ) and in conjunction with the FIGS. 3 and 4 an optically variable structure in which the embossing structure 4 of regularly arranged, uniform, line-shaped embossing elements 5 is formed, that is formed as a periodic line grid. The line-shaped embossing elements 5 are provided with a coating 7, which is designed as a multi-colored arrangement of non-linear base elements. The individual color surfaces of the non-linear base elements lie on the flanks of the line-shaped embossing elements. The formation of the line-shaped embossing elements 5 as elevations, which are preferably produced by embossing of the data carrier, can be clearly seen in the sectional view on the upper side of the data carrier. If the media is mechanically deformed with an embossing tool, the bottom of the data carrier material will show the negative deformation. The deformation is shown here only schematically. As a rule, the back of the data carrier will not have such a pronounced embossing pattern. In the following, only the upper or front side of the data carrier essential for the understanding of the invention will be described, as it is perceived by the observer during a view from the viewing direction AU. The deformation of the lower or rear is not essential to the invention, but only a by-product of special embossing techniques, such. B. the intaglio printing. However, it can serve as another authenticity feature.

The coating 7 according to the invention is in the FIGS. 3 and 4 shown in more detail. According to Fig. 3 the coating 7 is formed from regularly arranged in the form of a grid, non-linear basic elements 8 and 13. The elements 8 and 13 have different colors, which is symbolized by the different filling of the basic elements 8 and 13 forming circles. In addition to the in Fig. 3 The basic elements shown with round outline form are two further outline shapes of the basic elements in FIG Fig. 4 shown. The outline of the basic elements 13 is that of a symmetrical cross, whereas the outline of the elements 8 corresponds to a star, which can also be regarded as a special tooth toe. The basic elements 8 and 13 of Fig. 4 are arranged in a grid shape. The elements 13 in the FIGS. 3 and 4 relative to the elements 8 by half the screen width in a bottom-up direction 17 in FIG Fig. 3 postponed. Also in one in the FIGS. 3 and 4 not shown direction perpendicular to the direction 17, the non-linear base elements 13 are arranged offset from the base elements 8.

In the Fig. 3 from bottom to top oriented preferred direction 17 is determined by the grid-shaped arrangement of the basic elements 8 and 13. Along this preferred direction 17, a line-shaped embossing element of the embossed structure can be arranged so that, as a result, the in Fig. 2 shown in cross-section structure of coating 7 and embossed structure 4 results, if the basic elements 8, 13 are embossed with the embossing element 5 so that they come to lie approximately symmetrically to the center of the embossing element. To get to the structure of Fig. 2 Furthermore, a line-shaped embossing element 5 with an approximately semicircular cross-section, as in FIG Fig. 34d shown to be generated in the substrate.

In order to obtain a sharper tilting effect, a cross section according to the Figures 34c or 34h to get voted. An even greater gain of the tilting effect results from the choice of a profile according to the Figures 34a, 34b or 34f , In addition, other in Fig. 34 shown cross sections of the embossing elements are advantageously combined with the coating 7.

As easily from the Figures 2 and 3 is in a substantially vertical plan view of the inventive optically variable Structure visible all the coating formed from the basic elements 8 and 13 visible. On the other hand, when the viewing direction is changed from the top view (AU) to an oblique view from the direction B, the basic elements 8 arranged on one flank of the line-shaped embossing elements 5 dominate the visual image, while the base elements 13 arranged on the other flank of the line-shaped embossing elements 5 partially or completely covered by the embossing elements 5 (shaded). When viewed obliquely the optically variable structure from direction C, the basic elements 13 dominate the visual impression and the basic elements 8 are completely or partially shaded. This basic principle inherent in the optically variable structures 3 according to the invention is realized in an analogous manner when the linear embossing elements 5 are not rectilinear, as in FIG Fig. 3 but have the shape of a curved or curved line. The illustration of such a stamp in Fig. 4 illustrated line 6 is for illustration only. Of course, a much more complicated pattern, z. B. a spiral pattern to be embossed into the ground.

In the following, further coatings according to the invention will be described with reference to FIGS FIGS. 5 to 8 described. The coating 7 in Fig. 5 has basic elements 8, 9 of different color, the outline shape of which corresponds to a symmetrical "L". In this case, the basic elements 8 and 9 are arranged in a regular grid such that in each case a basic element 8 is combined with a basic element 9. The basic elements 8 and 9 thus form in pairs each a basic color element 52, which will be discussed in more detail.

Another variant of the coating 7 is in Fig. 6 shown. The coating 7 consists of regularly arranged, non-linear Basic elements 8, 9 and 13, each having the outline of an arch element. The basic elements assume the positions of a grid with a constant screen ruling.

But it is also possible that the basic elements, as in the FIGS. 7 and 8 shown, have an outline that is complementary to the outline of an adjacently arranged primitive such that there is a substantially full-surface coating 7. In this case, the elements can also be arranged in the same outline shape that results in additional information in the coating, as in Fig. 8 is shown.

Based on FIGS. 9 to 14 will be discussed in detail on further inventive optically variable structures. In Fig. 9 an embossed structure 4 is shown, which consists of three line-shaped embossing elements 5 with triangular cross-section. Each embossing element 5 has four flanks which rise above the plane formed by the substrate. The extending in the longitudinal direction of the linear embossing element 5 flanks are in Fig. 9 designated by the reference numerals 5a and 5b, while the two existing at the ends of the embossing element 5 flanks are provided with the reference numerals 5c and 5d. The grid width of the arrangement of the line-shaped embossing elements 5 underlying grid is denoted by x.

In Fig. 10 a coating 7 is shown, which in combination with the embossed structure of Fig. 9 in the Fig. 11 shows optically variable structure results. The coating 7 consists of two types of non-linear basic elements with different outline and different color. The basic elements 8 have a polygonal outline shape in the form of a rectangle. On the other hand, each basic element 9 has the outline shape a square and about half the area of the surface of a base element 8. The basic elements 8 and 9 are arranged at regular intervals on the positions of a grid. In each case a basic element 8 and 9 together form a color base element 52 which is arranged in a grid cell 12. The grid width x of the coating 7 corresponds to the grid width x of the embossed structure 4 of FIG Fig. 9 ,

If a substrate provided with the coating 7 is in the exact register with the embossed structure 4 Fig. 9 provided, the combined structure results Fig. 11 , While in a vertical view on the in Fig. 11 structure shown, the entire coating 7 is visually detectable, in principle, only the grid-like arrangement of the non-linear base elements 9 on the flanks 5b of the embossing elements 5 can be perceived in an oblique view from direction B. Conversely, only the basic elements 8 on the flanks 5 a of the linear embossed elements 5 can be seen from the viewing direction C. At the in Fig. 11 shown arrangement of the basic elements 9 at the base of each flank 5b are arranged between several line-shaped embossing elements 5 basic elements 9 very quickly shadowed by the flanks 5b adjacent stampings 5, when the angle of view from a substantially vertical view (AU in Fig. 2 ) is changed to a view from direction B. On the other hand, since the base elements 8 are arranged to come to rest on the flanks 5a of the embossing elements 5 to close to the amplitude 20, they may not, due to the shading by the embossing elements, change as viewed from a substantially perpendicular top view to the oblique view from direction C over a wide angular range on the flanks 5a.

In Fig. 12 is one opposite the in Fig. 9 shown structure varied embossed structure 4 shown. It comprises a line-shaped embossing element 5, which extends along a first preferred direction 16. Perpendicular to this, three further line-shaped embossing elements 15 are arranged along a second preferred direction 17. The grid width of the embossing element 5 is x, the grid width of the stamping elements 15 is y. In the present case, the screen widths x and y are the same size.

In Fig. 13 a coating 7 according to the invention is shown, which is formed by a grid-shaped arrangement of the non-linear base elements 8 and 9, wherein both basic elements have a rectangular outline shape and different colors. The basic elements 8 and 9 in turn form a basic color element 52, which is arranged in a grid cell 12. The combination of the embossed structure 4 Fig. 12 and the coating 7 Fig. 13 gives the in Fig. 14 Perspective shown combined structure. The observation from the directions B and C this time provides a completely different picture as in Fig. 11 because the line-shaped embossing elements 5 and 15 are arranged along two preferred directions. From the direction C, only the base elements 8 arranged on the flanks 5a can be seen from the direction B, the base elements 9 arranged on the flanks 5b, provided they are not shadowed by respectively adjacent embossing elements.

On the other hand, from the direction D the elements 8, from the direction E the elements 9 can be seen. The arrangement of the basic elements on the respective flanks of the embossing elements also influences the color shift effect of this structure.

Example 2 (FIGS. 15 and 16)

The in the FIGS. 15 and 16 illustrated coating 7 according to the invention comprises three types of different colored and non-linear basic elements 8,13 and 39, which are each arranged in the form of a grid with a constant screen ruling. In addition, in each case a base element 8, 13 and 39 are printed on the substrate, not shown further, that they form a color base 52. Corresponding to the regular arrangement of the individual elements, the color base elements 52 are also arranged in the form of a regular grid with a constant screen ruling. In each case, a color base element 52 lies in a grid cell 12 of the grid. The resulting array of color primitives 52 is divided into three subregions A, B and C in the illustrated preferred embodiment. Each subarea is provided with an embossed structure 4, not shown, of linear embossing elements 5. The alignment of the embossed structure 4 takes place in each subarea parallel to the preferred directions of the grid, wherein in Fig. 16 for each area A, B and C only one preferred direction is drawn and used to align the embossed structure. As in the case of the optically variable structures described above, the embossing results in the FIGS. 15 and 16 shown coating 7 a viewing direction-dependent optically variable effect. While the entire coating 7 can be perceived by a viewer in supervision, interesting tilting effects arise for any other oblique viewing directions, which are different for the individual areas A, B and C, since the embossed structures each have different orientations in these areas.

Example 3 (Figures 17a, 17b, 18a and 18b)

The in the FIGS. 17a and 17b illustrated coating 7 is formed from three round primitives 8, 9 and 13 different color, which in turn define a color primitive 52 in a grid cell 12 of a regular grid. Again, by the arrangement of the basic elements 8, 9 and 13 preferred directions along which an embossing takes place. In Fig. 17b the preferred directions are 16,18 and 19 located and the embossed structures 64 along the preferred directions shown schematically. The cross-section of the linear embossing elements is triangular and corresponds to the in Fig. 34a illustrated cross-section. The embossing structure 64 has amplitudes or zeniths 20 and intermediate valleys 21. Accordingly, the non-linear base elements 8 and 9 come to lie on a flank of the non-linear embossing element at a stamping of the coating 7 along the preferred direction 16, while the elements 13 come to rest on the other edge of the element.

If the dimensions of the basic elements 8, 9 and 13 are selected such that they are no longer perceived as separate elements by the human eye, a mixed color element which can be recognized in supervision results for a basic color element 52 defined by the basic elements 8, 9 and 13. The viewer perceives a mixed color resulting from the mixed color of the color base member 52 and the color of the substrate surface on which the coating is disposed, depending on the area coverage of the color base 52 in the grid cell 12. When viewed from a vertical view (AU in Fig. 2 In various directions, in the region of the linear embossing along the direction 16 on a flank of the embossing element, a mixed color resulting from the colors of the base elements 8, 9 and the color of the substrate surface is observed. On the other flank of the embossing element, however, the mixed color of the color of the base elements 13 and the color of the background is perceived from a direction opposite to this viewing direction. It is off Fig. 17b it can be seen that changes in an embossing along the preferred direction 19 resulting for the individual edges of the embossing element mixed color. In this case, when considering an edge, a mixed color results from the colors of the primitives 8, 9 and 13 and the color of the background. The perceived mixed color of the opposite flank, on the other hand, is defined by the color of the differently spaced elements 8, 9 and 13 and the color of the ground.

In Fig. 18a a further coating 7 according to the invention is shown, are arranged in the triangular basic elements 8, 9 and 13 in the form of a larger regular triangle. The arrangement of the basic elements 8, 9 and 13 in turn defines a color primitive in each grid cell 12 of a grid. Opposite the in Fig. 17a illustrated color primitives 52 are the color primitives of Fig. 18a through a larger area coverage of the subsoil. Consequently, the color impression, which can be perceived by the viewer in a plan view of a grid cell, is determined to a greater extent by the inherent color of the triangular basic elements 8, 9 and 13 or of the color base element. In addition, these basic elements in the plane of the coating 7 again define preferred directions, which are denoted by the reference numerals 16, 18 and 19 in FIG Fig. 18b are shown. If an embossing along these preferred directions with an embossed structure with a pointed profile, z. B. the profile Fig. 34a, 34b or 34f , resulting in color shift effects with extremely pronounced viewing direction dependence. If, for example, the colors of the primary color system CMY are used for the basic elements 8, 9 and 13, a substantially resulting for the coating 7 in plan view gray mixed color for the color primitives 52, which by a z. B. white color of the substrate is brightened a bit more.

Example 4 (Figures 18c and 18d)

In Figures 18c and 18d a further variant of the coating 7 according to the invention is shown. The non-linear basic elements 8, 9 and 13 in turn form a basic color element 52 in a grid cell 12 of a regular grid. The triangular basic elements 8, 9 and 13 have the colors of a primary color system, for example those of the primary color system CMY. In the example shown, the triangles 8 have the color cyan, the triangles 9 the color magenta and the triangles 13 the color yellow.

In contrast to the coating grid of Fig. 18a includes the coating 7 Fig. 18c two grids in the horizontal direction (direction 16 in Fig. 18d ) are arranged offset. How out Fig. 18c As can be seen, the color primitives 52 of the first and third lines of the coating shown belong to a grid, while the color primitives 52 of the second row are arranged in the grid cells 62 of the second grid. In this case, the grid cells 62 are offset from the grid cells 12 of the first grid by half the grid width in the horizontal direction 16.

Again, there are three preferred directions 16,18 and 19 for the arrangement of the line-shaped embossing elements (see schematic embossed structure 64). For example, if an embossing element of the second line of the coating 7 is superimposed in direction 16, come on a flank of the embossing element with z. B. triangular cross-section exclusively yellow triangles 13 for lying. When looking at this flank, the viewer sees exclusively yellow triangles 13 and the color of the ground, z. B. white, so that the result is a brightened yellow color. Conversely, on the other flank of the embossing element arranged in the direction 16, it can perceive a mixed color recognizable from the colors magenta and cyan of the basic elements 9 and 8 and the white background areas.

In an analogous manner, the arrangement of a line-shaped embossing element along the preferred direction 18 results in a viewing direction-dependent perception, wherein a flank of the embossing element due to the there exclusively arranged magenta triangles perceives a lightened by the color of the substrate color magenta. When looking at the other flank of the embossing element, however, results in a mixed color of the color of the substrate and the colors yellow and cyan of the basic elements 13 and 8 respectively.

Finally, the arrangement of an embossing structure along the preferential direction 19 for one flank will give the pure lightened color cyan, and the other flank a mixed color of the color of the substrate and the color magenta and yellow of the basic elements 9 and 13, respectively.

In supervision of the coating 7 of the Figures 18c and 18d In turn, for each color base element, a gray mixed color results from the color of the base elements 8, 9 and 13. Because of the white color of the background, the overall impression of the coating is therefore again a slightly brightened shade of gray. In the above discussion of the mixed colors results in a mixed color of the color primitives whenever the dimensions of the color areas of the individual primitives are below the resolution of the human eye.

Example 5 (Fig. 19)

In Fig. 19 is one of the in the Figures 18a and 18b reproduced coating similar coating 7 shown. However, in some grid cells of the coating 7, the arrangement of the basic elements 8, 9 and 13 of a color base element 52 differently than in the other grid cells 12. The grid cells with a changed arrangement of the elements are provided with the reference numeral 22 and ultimately form additional information within the coating. Depending on the orientation of the embossed structure with respect to the grid-shaped arranged color primitives, this additional information can be perceived in supervision and from certain directions. It represents an additional security feature inherent in the coating 7 according to the invention.

Example 6 (Figs. 20 to 26)

In the following, the generation of mixed color effects by the optically variable structure according to the invention will be discussed in more detail. In Fig. 20 is a section of the print image area 2 of the data carrier 1 of Fig.1 reproduced image motif. It can be with non-linear primitives of a color, z. B. black, arrange on a substrate. In addition, an embossed structure is provided, which runs in certain areas of the coating in a certain direction. An example of this is for the eye area of the picture motif in Fig. 25 shown.

As in Fig. 21 shown, the image section can also be done by grid-shaped, non-linear primitives that have one or more outline shapes and one or different colors. In the present case, the coating of the image motif by primitives 39 formed with a round outline shape, wherein the basic elements 39 for generating a color range associated with a certain area of the image motif have a different thickness filling. For example, the basic elements 39 are substantially completely filled in the region of the hair of the person depicted, whereas the basic elements 39 in the region of the forehead are circular rings, in the center of which the color of the substrate, e.g. B. white, can be perceived. In addition, the color of the primitives can be varied for each image area.

Furthermore, in Fig. 22 the image section FIGS. 20 and 21 shown with a coarser grid of basic elements 13. In each case two arcuate or circular segment-like basic elements 13 are arranged in a regular grid. By varying the area filling of the individual basic elements 13, the image detail can be reproduced with sufficient contrast. Of course, it is also possible that in each case two basic elements 13 of different color are arranged to a color base element and for a particular color basic elements in supervision a mixed color results, which is derived from the color of the basic element pair and recognizable in a grid cell from the ground color. Also in the FIGS. 21 and 22 coatings of the invention shown are provided with suitable embossing structures, in turn, different orientations of the embossing elements are provided in individual image areas. Although a picture motif with rectilinear sections defines a plurality of preferred directions (see Fig. 26 with the preferred directions 16 to 19), can also be used for the image areas of FIGS. 21 and 22 find distinctive preferential directions, as this is based on Fig. 25 is shown by way of example.

The interaction of color primitives and line embossing structure to achieve impressive color shift effects with mixed colors is based on the FIGS. 23 and 24 described in detail. At the in Fig. 23 illustrated coating 7 according to the invention may be a greatly enlarged section of the image of the Fig. 21 act. Non-linear basic elements 8, 9 and 13, each of a different color, are arranged in the form of a grid with constant screen rulings x and y. In each case one basic element 8, 9 and 13 form a basic color element 52, which is arranged in a grid cell 12 of the grid. Each color primitive 52 corresponds to exactly one pixel of a colored image motif, e.g. B. the in Fig. 21 illustrated motif. Each pixel of the image motif is assigned a specific color component of a color system. In the present case, the basic color system CMY is used. Accordingly, the primitives 8, 9 and 13 of each color base 52 of the coating 7 have the colors cyan, magenta and yellow. The color component of a pixel is determined by the size of the colored areas of the primitives 8, 9 and 13. The human eye, because of its limited resolution, can not perceive the basic elements separately from one another, and therefore, when viewing the coating 7, only recognizes the mixed color of each color base element 52 defined by the colored surfaces of the basic elements. It should be noted that if the cover is not complete the background due to the color of the substrate results in an additional color component, which, however, only leads to a whitening of the visually perceived mixed color of the color base element 52 when a white background is selected. On the other hand, a color primitive 52 can also be readily designed to substantially completely cover the surface of a halftone cell 12, whereby only the mixed color of the color primitive 52 determines the color of a pixel of the image motif.

As in Fig. 23 1, the size of the colored area of a primitive is varied so that the color proportion of each primer 52 is accurately determined. Thus, in supervision of the coating 7, an image motif to be displayed results in a color that is precisely defined for each individual pixel.

The interaction of such a coating with line-shaped embossing elements leads to an optically variable structure according to the invention, as described in US Pat Fig. 24 is reproduced. The embossed structure 4 comprises linear embossed elements 5 and 15, the former along the preferred direction 16, the latter along the preferred direction 17 are arranged. The grid width x and y of the line-shaped embossing grid 5 and 15 corresponds exactly to the grid widths x and y of the coating 7. Off Fig. 24 It can be seen that the arrangement of the embossing elements in the region of the coating 7 virtually does not change the visual impression in plan view. That is, due to the limited resolution of the human eye, only the mixed color associated with a color primitive 52 is perceived in the region of a halftone cell 12 of the coating. When viewing from a different angle from the angle, z. B. from the direction 17, however, a completely different image is perceived by the viewer. For example, lies on the flank 5a of the embossing element 5, only the color surface of the base member 8, while on the flank 5b, the color surfaces of the basic elements 9 and 13 come to rest. Accordingly, results for the flank 5b within the grid cell 12 of the embossing element 5 defined by the color surfaces of the basic elements 9 and 13 and the color of the substrate mixed color, while for the flank 5a within the same grid cell 12, the perceptible color of the intrinsic color of the primitive 8 and the color of the substrate. The same applies to each grid cell 12 of the coating 7, which is provided with an embossed structure is. In this way it is possible to depict pictorial motifs in true colors and at the same time to provide the motifs with an impressive color-shifting effect.

Example 7 (Figs. 27 to 29)

The FIGS. 27 to 29 show a further variant of an optically variable structure according to the invention, in which tilting effects as well as mixed color effects generated by the overlapping of basic elements are combined with each other. In Fig. 27 an embossed structure 4 with line-shaped embossing elements 15 is shown. Unlike the in Fig. 12 shown embossed structure, the embossing elements 5 and 15 of the Fig. 27 the in Fig. 34g or 34f shown cross section.

In Fig. 28 a coating 7 according to the invention is shown, which with the embossed structure 4 of Fig. 27 is combined into an optically variable structure. The coating 7 is formed from three types of non-linear base elements 8, 9 and 13, which are each arranged in the form of a regular grid. According to the grids formed by the basic elements 8 and 9, basic elements with a filling and thus a large area coverage of the grid for this coating variant are particularly well suited. In addition, in principle, other basic elements, such as the alphanumeric characters 13, are used. It is off Fig. 28 It can be seen that the arrangement of the basic elements and thus of the grid defines the preferred directions 16 and 17. The coating grid 7 also has a grid width x in the direction 17 and a screen width y in the direction 16 which corresponds to the screen widths of the embossed pattern 4 Fig. 27 equivalent. The basic elements of a grid have a certain color, z. For example, the colors red, green, and blue of the RGB primary color system. In the areas defined by the arrangement of the grid overlap the basic elements of the differently colored grid and form a defined mixed color in these areas. The coating 7 thus appears in plan view as a superimposition of differently colored rasters which have a mixed color in the areas of overlap. The arrangement of the overlapping areas corresponds to the picture elements of an image motif or of a geometric pattern, so that the image motif or pattern can be seen in a grid of basic colors corresponding to the mixed colors when viewed from above. In combination with the embossed structure Fig. 27 This results in an optically variable structure, which reveals in plan view the coating described above and from other viewing directions, the color structures dependent on the embossed structure 4.

In the FIGS. 29a to 29c further coating grids 7 according to the invention are shown. For reasons of clarity, the nonlinear basic elements which form a grid are not shown individually, although these are similar to those in FIG Fig. 28 spaced from each other are arranged in a grid. How out Fig. 29a it can be seen, the grid formed from the basic elements do not intersect at right angles, so that there are three preferred directions 17, 37 and 47 for a possible arrangement of the embossed structure. The arrangement of the raster in turn results in overlapping areas of the basic elements of different rasters, so that the coating 7 produces a complicated structure of pixels with mixed colors and the pure colors of the basic elements in plan view. The arrangement of the grid is so precise on the ground that the arrangement of the mixed color areas in itself constitutes a security feature that is combined with the caused by the embossing pattern tilting effect.

In Fig. 29b is the coating grid 7 off Fig. 29a shown in a variant. In this case, a colorless area 39 was inserted around the grid formed by the basic elements 9. This results in a dependence of the arrangement of the basic elements 13 of the white areas 39 and the basic elements 9. The resulting spatial dependence of the basic elements 9 of basic elements of other grid and the inserted areas 39 provides an additional security feature of the coating. 7

In Fig. 29c a further variant of a coating grid 7 is shown with mixed color effects. In this case, an area 38 has been added around the grid formed by the primitives 8, resulting in a division of the grids formed from the primitives 9 and 13. The spatial dependence of the basic elements on the basic elements of other rasters is an additional security feature that is currently difficult to follow. In addition, resulting from coating 7 of Fig. 29c Overlapping areas with mixed colors, which lead to viewing direction-dependent tilting effects by arranging an embossing structure.

Example 8 (Figures 30 to 34)

In the Fig. 30 shown coating 7 consists of elliptical basic elements 8, 9 and 13 of different colors. In contrast to the previously described coatings 7, a direction 47 is shown which does not correspond to a preferred direction of the coating grid. If the arrangement of the line-shaped embossing elements along this direction, a tilting effect results from viewing directions that do not match the preferred directions of the coating grid. Is the coating 7 arranged in the direction of 47 embossing structure in a further coating 7 is integrated, in which the embossing takes place along one of the preferred directions of the coating 7, the imaged area of the Fig. 30 an additional information within the entire coating.

In the Figures 31, 32 are cross sections of embossed structures shown in which additional information 40 is included. In the case of in Fig. 31 the structure shown, the additional information 40 is generated by a change in the grid width of the stamping grid. In contrast, the additional information in the embossed structure of the Fig. 32 by a change of the cross section of the linear embossing elements from circular to triangular.

The additional information of the coating can also be easily arranged in a stamping structure designed for this purpose, as is shown by the example of the structure of FIG Fig. 33 is apparent. The embossed structure of a triangular cross section has amplitudes 20 and a relatively large grid width, so that base regions 31 remain between the individual line-shaped embossing elements, which can be provided with the additional information of the coating. The additional information introduced there is visible in plan view and from certain viewing directions and shows a tilting effect inherent to the optically variable structure according to the invention.

In Fig. 34 Different cross-sections of line-shaped embossing elements are shown. It should be noted that also cross sections are possible, which represent a combination of the cross sections shown. Also, the flanks of the cross section, z. B. the Fig. 34m be concave.

Example 9 (Figures 35a, 35b, 36a and 36b)

The preparation of a data carrier according to the invention is in the Figures 35a, 35b and 36a, 36b explained.

Preferably, the optically variable element is produced by printing technology. For this purpose, the coating in any printing process, preferably in offset printing, on a substrate, preferably the document material, printed and then this coating is embossed with a stamping tool accordingly. As a stamping tool, a gravure printing plate is preferably used. This procedure is in the Figures 35a and 35b shown.

The Fig. 35a shows a data carrier according to the invention in cross section before the embossing process. In this case, the data carrier substrate 10 is first with a background layer 29 z. B. printed over the entire surface. In addition, the coating of base elements 26, 27 is applied.

The background layer 29 may also be in the form of information and patterns. It is also possible to use special printing inks which further increase the counterfeit protection effect of the optically variable element. These may be optically variable printing inks, such as printing inks containing interference pigments or printing inks containing liquid crystal pigments, or metallic effect paints, such as gold or silver effect paints.

The Fig. 35b shows a sectional view of the data carrier after the embossment, which was generated in the example shown as blind embossing in intaglio printing. The embossment is placed so that the coating with basic elements 26, 27 comes to rest on the flanks of the embossed structure. Alternatively, the substrate 29 may also be applied in a different process, for example in a transfer process, over the entire surface or likewise provided with recesses or a pattern. In this case, metallic pattern elements or coatings can be applied in the transfer process.

On the background layer 29 can be completely dispensed with, as in Fig. 36a shown. In contrast, the embossing, which is produced for example in steel intaglio printing, executed in color.

The Fig. 36a shows the structure before embossing with substrate 10 and coating 26, 27. In the Fig. 36b the situation is shown after the coinage. The Indian Fig. 36b The structure shown was ink-carrying embossed, so that congruent to the embossing is a color layer 30 is present. The additional color layer 30 comes to lie as the uppermost layer, since this embossing was carried out here as the last process step.

Preferably, an at least translucent color is used for the color layer 30. The ink-bearing intaglio printing can be carried out in a modification so that an application of paint takes place only on the non-linear embossing elements, the valleys between the non-linear embossing elements, however, remain free of color.

In one development, a color with machine-readable additives, such as, for example, luminescent substances, can be used for the color layer 30.

Claims (15)

1. A security element with an optically variable structure (3) having an embossed structure (4) with line-shaped embossed elements (5, 15), and a coating (7), the embossed structure (4) and the coating (7) being so arranged that at least parts of the coating (7) are completely visible upon perpendicular viewing but concealed upon oblique viewing, characterized in that substantially the total coating (7) is formed from non-line-shaped primitives (8, 9, 13, 26, 27, 39) which are characterized by the parameters of outline form, size, color and orientation, and so combined with the embossed structure (4) that different information becomes visible upon a change of viewing direction.
2. The security element according to claim 1, characterized in that the non-line-shaped primitives have a circular, oval and/or polygonally bounded, in particular triangular, square or rectangular, outline form.
3. The security element according to claim 1, characterized in that the non-line-shaped primitives have an outline form determined by a symbol, geometrical pattern and/or alphanumeric character.
4. The security element according to at least one of claims 1 to 3, characterized in that the non-line-shaped primitives have a substantially all-over filling.
5. The security element according to at least one of claims 1 to 4, characterized in that the non-line-shaped primitives have a dimension of 10 µm to 500 µm, in particular of 20 µm to 250 µm, the dimension of a non-line-shaped primitive preferably not amounting in any direction to more than four times the dimension in one of the other directions.
6. The security element according to at least one of claims 1 to 5, characterized in that the coating comprising non-line-shaped primitives is a printed layer, in particular an offset, intaglio, screen, flexographic, xerographic, ink-jet or thermographic printed layer, or a layer incorporated by a laser printer or by the action of laser radiation.
7. The security element according to at least one of claims 1 to 6, characterized in that at least a portion of the non-line-shaped primitives is arranged in a grid.
8. The security element according to at least one of claims 1 to 7, characterized in that respectively at least two non-line-shaped primitives of different color, in particular of different color of a primary color system, are arranged in the form of color primitives, preferably at least a portion of the color primitives being arranged in a grid.
9. The security element according to claim 7 or 8, characterized in that the grid of the primitives or of the color primitives has a constant grid spacing.
10. The security element according to at least one of claims 8 to 9, characterized in that the optically variable structure has a multiplicity of color primitives which represent upon perpendicular viewing a multicolor picture motif and/or geometrical pattern whose visual impression varies upon a change of viewing angle.
11. The security element according to at least one of claims 1 to 10, characterized in that the optically variable structure has additional information which arises through variation of the coating, in particular through a variation of the form, color and/or the arrangement of the non-line-shaped primitives, such as offset, change of grid spacing, omission, mirroring of single or several non-line-shaped primitives, or through arrangement of information individualizing the optically variable element, such as alphanumeric characters or bar codes, and/or arises through variation of the embossed structure, in particular through a variation of the form, size, height and/or the arrangement of the line-shaped embossed elements, such as offset, change of a grid spacing, omission of single or several line-shaped embossed elements.
12. A data carrier with a security element according to any of claims 1 to 11, wherein the data carrier is preferably a paper of value, in particular a bank note.
13. A method for producing a security element with an optically variable structure (3) having an embossed structure (4) with line-shaped embossed elements (5, 15), and a coating (7), the embossed structure (4) and the coating (7) being so arranged that at least parts of the coating (7) are completely visible upon perpendicular viewing but hidden upon oblique viewing, characterized in that a substrate is provided with non-line-shaped primitives (8, 9, 13, 26, 27, 39) which form substantially the total coating (7) and which are characterized by the parameters of outline form, size, color and orientation, and that the non-line-shaped primitives (8, 9, 13, 26, 27, 39) are so combined with the embossed structure (4) that different information becomes visible upon a change of viewing direction.
14. The method according to claim 13, characterized in that the non-line-shaped primitives are printed on the substrate and/or produced by the action of laser radiation, the print or the application of the non-line-shaped primitives to the substrate preferably being effected before the production of the embossed structure.
15. The method according to at least one of claims 13 to 14, characterized in that the embossed structure is produced by intaglio printing, there being printed on the substrate preferably simultaneously with the incorporation of the embossed structure a further ink layer which is arranged congruently to the raised areas of the embossed structure.

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