EP2007586B2 - Security element with authenticity features identifiable in a visual and tactile manner - Google Patents

Description

The invention relates to a security element according to the preamble of independent claim 1. The invention further relates to a method for producing such a security element and a data carrier with such a security element.

For protection against counterfeiting, in particular 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 provided with security elements which are printed on both sides, have translucent substrate. The protection against forgery of such a security element is based on the fact that in addition to the printed images of the two sides of the carrier material visually also an image can be perceived that results in transmitted light as a superposition of the front and back printed images. The visible image can not be reproduced or insufficiently reproduced by the abovementioned reproduction devices, as a result of which counterfeiting can be easily recognized.

This is for example from the DE 32 08 204 A1 a printing method for securing banknotes and other documents against unauthorized copying, in which z. B. a banknote from a translucent paper or other carrier material on the front and back with a periodic or almost periodic dot or line pattern is printed. In a variant of the method described in this document, the dot or line pattern in arbitrary sub-areas of the front and back are intentionally offset from each other, so that moire images are generated, which can be detected in transmitted light with the unaided eye and evaluated as an authenticity feature. Although the documents produced by this process variant provide some protection against imitation, it proves to be disadvantageous that the authenticity feature of a person can be perceived only with the eyes as a sensory organ. Moreover, it may be relatively difficult for the male or female on the street to distinguish an authentic moire structure from a moire structure that results from viewing a counterfeit bill or similar security document.

Out CA 1 019 012 A1 is a value document, such as a banknote, known, which is provided in a partial area of its surface with a full-surface print pattern. In order to produce an optically variable effect, the data carrier is additionally provided with an embossed structure in the region of this print pattern so that flanks of the embossed structure are formed which are only visible at certain viewing angles.

Out WO 02/20274 A1 a data carrier, such as a banknote, identity card or the like, is known, which has a security element which is at least visually testable and has an embossment in at least one subregion. The embossing is executed in non-color-leading intaglio printing as halftone blind embossing. From the WO 02/20274 A1 Furthermore, it is also known to print a substrate in the so-called color-leading intaglio printing.

The invention is therefore based on the object, a security element of to propose the type mentioned, which avoids the disadvantages of the known generic security elements, provides an increased level of security against counterfeiting and can be checked at the same time in a simple manner to its authenticity. 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.

In the case of the security element according to the invention, the first line print pattern is combined congruently with an embossed structure which is produced by a gravure printing method. Under embossing structure is understood below any structure that consists of raised and recessed areas of the substrate and can be produced with the embossing tools commonly used in intaglio printing. The embossing tools are deeply engraved plates using various techniques.

Furthermore, in the case of the security element according to the invention, the first line pressure pattern interacts with the second line pressure pattern in such a way that at least one partial area has a visually recognizable information that is indicative of the authenticity of the security element. In the following, a periodic line pressure pattern is understood to mean any pattern whose periodicity satisfies the definition given in the Paperback of Mathematics, Bronstein, Semendjajew, 25th edition. Accordingly, the dots or lines forming the line-printing pattern are arranged regularly, that is, as shown in FIG. H. the patterns have a recurring interval with respect to the spacing of the dots or lines.

An almost periodic line pressure pattern will be understood below to mean any pattern that is not exact but only approximately periodic. In particular, the guilloches used in banknote printing, i. H. fine geometric line patterns or ornaments, understood as almost periodic patterns.

It should also be noted at this point that for a viewer, a dot matrix can also appear as a line grid, depending on the size and the distances of the dots when the visual resolution is not reached. For the subject of the invention, however, a sharp demarcation between point and line grids is not required, which is why such is dispensed with.

Finally, it is also noted that the perceived impression of the first and second line pressure pattern always refers to a reflection in incident light, that is to say in reflection, unless it is expressly pointed out that it is the visual impression of the line print pattern in review, ie in transmission.

Due to the combination of the first line printing pattern generated in intaglio printing with an embossed structure of the same screen width, the security element has not only visual but also haptically detectable authenticity features. The security element thus represents a detectable with the eyes and the sense of touch so-called human feature that allows the authenticity check by the man or the woman on the street in a simple manner. In addition, the combination with the eyes of perceptible and palpable authenticity features further enhances the protection against counterfeiting, as the Embossed structures of the security element with conventional reproduction techniques, such. B. color copiers, basically can not be played.

The embossing structure provided on the first side of the carrier material is to a certain extent always also present as a negative embossed structure on the second side of the carrier material, for which reason the security element can be detected haptically on both sides. As a result, the security against counterfeiting is further increased and the security element has on both sides the grip that the user perceives as typical for a document of value.

Furthermore, it proves to be an advantage that the information characterizing the genuineness that is recognizable by the interaction of the first and second line pressure patterns in at least one partial area is present. In the case of the information perceptible in transmitted light, any information that indicates the authenticity of the security element to the viewer without the use of auxiliary means is understood below. The easily recognizable additional information of the security element further increases security against counterfeiting since it can not be reproduced or can only be reproduced very insufficiently by reproduction techniques such as scanners or color copiers.

According to the invention, it is provided that the first line printing pattern is a printed layer produced by intaglio printing. The carrier material is provided simultaneously with the first line-printing pattern and the embossing structure according to the invention, since the intaglio printing method, in addition to the production of the embossed structure, enables simultaneous application of the printing ink. Such pressure is also referred to as color leading intaglio printing. By the simultaneous application or arrangement of the first line printing pattern or the embossing pattern in intaglio printing, the first side of the security element according to the invention can be produced in a single process step, which proves to save time and costs.

Furthermore, it is provided according to the invention to arrange the printed layer essentially congruent with the raised regions of the embossed structure; This enables a precise combination of line pattern and embossed structure. The user can perceive the color relief created in color-guiding intaglio printing very well with his sense of touch and his eyes.

According to the invention, it is further provided that the first line pressure pattern is a line grid with a constant screen ruling. The constant raster print pattern represents a special case of a periodic print pattern, but with the proviso that it has only a defined period that does not change within the print pattern. The printed pattern with a constant screen ruling can be produced relatively accurately with today's printing techniques and, moreover, fits well into an image motif or geometric pattern which may be present on the respective side of the security element.

According to the invention, the embossed structure of the security element is a line grid with a constant screen ruling. Such an embossed structure can be produced precisely with the intaglio technique. The embossed structure is combined with a linear printing pattern of the same screen ruling as a line raster. If print pattern and embossed structure, as described above, are generated in a single process step and thereby Each well of intaglio printing plate is filled with color, can be accomplished by this method variant in a simple manner, the combination of a print pattern and a stamping structure of the same screen ruling.

It is also expedient for the embossing structure of the first side on the second side of the data carrier to form a substantially negative embossing structure which cooperates with the second line pressure pattern to form an optically variable structure such that at least parts of the second line pressure pattern are completely visible when viewed perpendicularly , but are concealed when viewing at an angle. As already mentioned, the embossing structure of the first side always produces, to a certain extent, a negative embossed structure on the second side. If the raised and recessed areas on the second side are sufficiently high or low and combined with a suitable printing pattern, the result is always an optically variable structure on the second side. This structure can also be combined with an optically variable structure on the first side of the carrier material. Such a security element with an optically variable structure on both sides of the substrate proves to be exceptionally forgery-proof and gives the security element a high degree of tactility.

In a further advantageous embodiment, it is provided that the points or lines of the subregions are offset relative to the points or lines of the remaining second line pressure pattern offset by a fraction of the grid width of the line grid. Particularly preferred is an offset by one third of the grid width of the line grid. In this way, one obtains portions with a relatively clearly defined offset from the rest of the print pattern.

The second line pressure pattern has several subregions. In this way, the information that can be seen in the clear and that characterizes the authenticity of the security element can be generated redundantly, which is why it may still be visible even after partial destruction of the security element.

It is also expedient for the line pressure pattern to have a plurality of subregions which form a second information which has subareas in the horizontal direction and subareas in the vertical direction, where m, n ≥ 1, preferably m, n ≥ 2. In addition to an arrangement in a matrix with a column and a plurality of rows, a checkered arrangement with m = n is also advantageous. This embodiment increases the security against forgery of the security element, because the see-through information remains visible even if a part of the partial areas is destroyed in the undamaged partial areas. On the other hand, the security element can be technically complex and thus inherently produce counterfeit-proof.

In a further preferred embodiment of the security element is provided that the points or lines of the subregions are arranged offset from the points or lines of the remaining second line pressure pattern by different fractions of the grid width of the line grid. Due to the different offset of the points or lines in the different subregions, a different brightness of the subregions results when viewed through, because the points or lines of the first and second printing patterns overlap to different degrees. As a result, information characterizing the authenticity can be perceived in the different subareas with a different brightness, which is very appealing to the viewer.

In a further embodiment, it is provided that the second line pressure pattern is a stitch depth, offset, screen, flexo, xerographic, inkjet, thermographic printing or a print layer generated by a laser printer. As already mentioned, the printing pattern, depending on the method used, has certain properties which are known per se to a person skilled in the art. Since, in addition to the second, the first line printing pattern is also produced by intaglio printing, a security element is obtained which has a combined pressure-embossing structure on both sides. Of course, the layer thickness of the carrier material and the parameters of the embossments for this case must be chosen so that a mutual destruction of the embossed structure of one side is avoided by the embossing structure of the other side. On the other hand, it may well be desirable to reinforce a negative embossed structure which is introduced on one side and to some extent present on the opposite side by the arrangement of the second embossing structure on the opposite side.

It is also advantageous if a part of the second line pressure pattern is generated by the action of laser radiation. Possible sources of radiation here are CO ₂ lasers, Nd: YAG lasers or other laser types in the wavelength range from ultraviolet (UV) to far infrared (IR), where 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 intended for the printing patterns. Since the spot size of the laser radiation can vary from a few micrometers to a few millimeters depending on the application, the printing patterns 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.

Provided that the carrier material used is absorbent for the selected wavelength range of the laser radiation or the carrier material contains an additive which absorbs this radiation, a part of the second line pressure pattern can be produced by discoloring the carrier material. However, the generation of line screens in a print image previously applied by a printing method is preferred. In this case, part of the previously applied print layer is removed by the action of the laser radiation and a finely structured line screen is produced.

In order to further increase the security against counterfeiting, it is provided in a further advantageous embodiment that the first and / or the second line pressure pattern is an at least partially multi-colored layer. In this way, in addition to a different color scheme of the first and second printed pattern in transmitted light interesting mixed color effects can be generated, which also increase the security against imitation.

The first and / or second line printing pattern may further be an optically variable printing ink or a metallic effect ink. As a metallic effect color gold or silver effect colors can be used with advantage. As optically variable printing ink, preference is given to using interference-layer pigments or printing-ink containing liquid-crystal pigments. These optically variable inks produce a viewer's view depending on the viewing angle certain color. Furthermore, the use of these printing inks further increases the protection against counterfeiting.

It can also be expedient for the first and / or second line printing pattern to have machine-readable properties at least in some areas, since such a security element has authenticity features which can be checked in a further security level in addition to the so-called human features. Such a review may, for. B. for banks and similar institutions of interest.

According to a further embodiment, the security element can have further layers and authenticity features, such. B. an additional translucent, optically variable layer or a film element. The additional translucent layer can be applied with advantage in a color-guiding stitch print on an already printed line print pattern. It is also conceivable, however, both the print pattern and the additional translucent, optically variable layer in separate process steps, for. B. in offset or Nyloprintdruck to apply to the print pattern. The use of a translucent, optically variable layer, when viewed in a plan view of the print pattern, causes the color of the print pattern to change depending on the viewing direction. A pronounced color shift effect is achieved especially with dark colors for the print pattern, such as black or dark green. At the same time, however, due to the transparency of the additional optically variable layer, the visibility of the transparency information is in no way impaired. A security element according to this embodiment is relatively expensive to manufacture, but at the same time very well protected against counterfeiting.

The aforementioned additional layers and elements may be superposed or underlaid to the first and / or second print pattern.

The visually perceptible information of the at least one subarea is preferably an alphanumeric character, symbol and / or geometric pattern. The alphanumeric character may be, for example, the denomination of the volume, e.g. B. a banknote, act, having the security element. Particularly tamper-proof, but at the same time very elaborate, is an individualized security element, which reveals an individualizing information that characterizes the authenticity. The alphanumeric characters may use characters of all known fonts, although characters from the standard Latin and Greek fonts are particularly preferred. As a symbol, for example, to think of a cross, double cross symbol, polygonal limited entities or a circle. The geometric patterns may be z. For example, it can be a guilloche pattern or the outline of a snowflake.

It goes without saying that the visually perceptible information is different in different subareas or else the individual information of the subareas is complementary to a total information, for example a value number.

In principle, any translucent carrier material can be used for the security element. In this case, the light transmittance must be at least so great that in transmitted light the information contained in at least one subregion can be visually perceived. The use of an additional lighting means for Improvement of the recognizability of the information by the observer is conceivable, although the thickness of the material is chosen so that a perception of the transmitted light feature is possible even without aids. Furthermore, the carrier material used must have properties which make it possible to introduce the embossed structure according to the invention by intaglio printing.

Accordingly, paper, in particular cotton vellum paper, is preferred as carrier material. Of course, it is also possible to use paper which contains a proportion of polymeric material in the range of 0 <x <100% by weight.

Furthermore, it is preferred that the carrier material is a plastic film. Suitable materials for the film are, in particular, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PA (polyamide) and PE (polyethylene). The film may also 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. The tools required for exploiting these properties, such as polarization filters, are known to the person skilled in the art.

It may also be expedient if the carrier material is a multilayer composite which has at least one layer of paper or a paper-like material. Such a composite is characterized by an extremely high stability, which is for the durability of the security feature of great advantage and also increases the security against counterfeiting.

It is also conceivable, however, to use a multilayer, paper-free composite material as the carrier material. These materials can also be used to advantage in certain climatic regions of the world.

All materials used as the carrier material can have additives which serve as authenticity features. It is primarily to think of luminescent, which are preferably transparent in the visible wavelength range and in the non-visible wavelength range by a suitable tool, for. B. a UV or IR radiation emitting radiation source, can be excited to produce a visible or at least detectable luminescence. Other security features can be used with advantage, provided that they do not affect or only slightly affect the viewing of the printed pattern in supervision or the information in transmitted light.

The security element according to the invention can be applied to a data carrier, such as security and value documents, such as banknotes, stocks, bonds, certificates, vouchers, bank and ID cards, passports or the like. The disk is equipped in this way with an easily recognizable even to the layman security element to increase the protection against counterfeiting. Also, the security element according to the invention can be used very advantageously in the field of product protection. In this case, the security element can be applied to appropriate labels or packaging or the product itself.

A data carrier which has a watermark and a security element arranged at least partially in the region of the watermark is also particularly preferred having. As a result, a known authenticity feature is advantageously combined with the authenticity feature according to the invention and the counterfeit security is further increased.

For the production of the security element according to the invention, a translucent substrate is provided with the first and second line printing patterns and the embossed structure is generated in register, wherein the first line pattern and the embossed pattern are produced simultaneously in the intaglio printing method in a single method step. The second printing layer can be printed 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.

The production of the embossed structure by means of a gravure printing plate as embossing tool. The embossed structure is produced in color-guiding intaglio printing, the first printed pattern being congruent to the embossed structure.

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.

It should be mentioned at this point that especially for double-sided printing, a printing plate can be used which, in the region of the first printing pattern, has a depression which accommodates at least a partial region of the first printed pattern in order to protect it from the effects of the printing of the second printed pattern , By using such special printing plates remain relief height and shape of the first printing pattern or the embossment on the first page before the influence of the printing process on the second side, in particular an adverse calendering spared.

Reference to the following embodiments and additional figures, the advantages of the invention will be explained.

The proportions shown in the figures do not correspond to the conditions present in reality and serve only to improve the clarity.

Fig.1

die Vorderseite eines Datenträgers mit der ersten Seite eines erfindungsgemäßen Sicherheitselements in Aufsicht,

Fig. 2

die Rückseite des Datenträgers der Fig. 1 mit der zweiten Seite des erfindungsgemäßen Sicherheitselements in Aufsicht,

Fig. 3

die Vorderseite des Datenträgers der Fig. 1 mit dem erfindungsgemäßen Sicherheitselement in Durchsicht,

Fig. 4

die zweite Seite des erfindungsgemäßen Sicherheitselements gemäß Fig. 2 in einer vergrößerten Aufsicht,

Fig. 5

ein als Beispiel angeführtes Sicherheitselement

Fig. 6

ein weiteres als Beispiel angeführtes Sicherheitselement.

Show it:

Fig.1

the front of a data carrier with the first side of a security element according to the invention in supervision,

Fig. 2

the back of the disk of the Fig. 1 with the second side of the security element according to the invention in supervision,

Fig. 3

the front of the disk of the Fig. 1 with the security element according to the invention in view,

Fig. 4

the second side of the security element according to the invention according to Fig. 2 in an enlarged view,

Fig. 5

an exemplary security element

Fig. 6

another exemplary security element.

The Fig.1 shows a data carrier 10 according to the invention in the form of a banknote with a security element 3, which is placed in the print image area of the data carrier 10. The security element 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 further features such as security threads, watermarks, etc., to determine the authenticity. The provision of such features is particularly useful for banknotes, but also for other monetary documents, such as stocks, checks and the like. As a data carrier in the context of the invention are also labels, passports or cards into consideration, as they are today z. B. for the identification of persons or goods, or to carry out other transactions or services.

All security elements according to the invention have in common that they and the resulting effects using the currently known reproduction techniques, in particular copying machines, can not be imitated, since these devices can only reproduce the respective side of the security element in supervision, so that the see-through effect is lost. In addition, the imitation will usually fail due to the low resolution of the reproductive devices. Finally, the reproduction techniques naturally do not reproduce the embossed structure, which also contributes to the protection against counterfeiting.

In the following, examples of two preferred embodiments of the invention will be explained with reference to the figures. The representation of the figures is highly schematized for better understanding and does not reflect all the facts.

The embodiments described below are reduced to the essential core information for the sake of clarity. In practical implementation, single or multi-color print patterns may be used as the first and second line print patterns, respectively. As a rule, the embossing structure has an embossing height in the range from 10 μm to 250 μm, preferably from 50 μm to 120 μm. The described 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 only the design and mutual association of the first and second printing pattern or the embossed structure is shown in order to illustrate the optical effects of the security element according to the invention.

How out Fig. 1 it can be seen, has the security element 3 on the first side of the carrier material, which in the present case is a cotton vellum paper of the banknote, a first printed in intaglio printed pattern. The print pattern is around a line pressure pattern with a constant screen ruling. The grid width is chosen so that it fits visually into the design of the surrounding guilloche pattern 11. The printing of the line printing pattern 1 and the guilloche 11 on the front side 12 of the banknote was carried out in a color-guiding intaglio printing method, wherein at the same time an embossing pattern of the same screen width was produced.

On the back 13 of the banknote 10 and thus on the second side of the security element 3 is according to Fig. 2 a line pressure pattern 2 that can be generated from the mirror image of the first print pattern by producing a print pattern that is substantially mirror-inverted relative to the first print pattern, portions of which are offset from the rest of the gel image.

Fig. 3 now shows the front side 12 of the banknote 10 in review. It can be seen that the first and second line printing patterns 1 and 2 overlap in transmitted light in such a way that information 7 is visually detectable, which represents the denomination of the banknote, namely "500". The information 7 is in reality still detectable in two further subregions of the security element 3 (above and below the information 7), but with a different contrast, which coincides with the in Fig. 3 selected reproduction technique can not be sufficiently represented.

In the following, details of the security element according to the invention will be described with reference to FIG FIGS. 4 to 6 described.

The line printing pattern 2 has partial areas in which the lines are offset from the surrounding lines. According to Fig. 4 the areas 4a, 4b and 4c represent a pattern which has the same screen width as the printing pattern 1 and is printed in mirror image on the back 13 of the banknote 11.

Furthermore, the line pressure pattern 2 has areas in which the lines are offset relative to the lines of the remaining areas of the print pattern 2, in particular of the areas 4a, 4b and 4c. For example, these are the areas 5a, 5b and 5c and 6a, 6b and 6c. In the present case, the regions 5a to 5c interact with the corresponding regions 6a to 6c in such a way that they encode information. In the illustrated embodiment, this is the denomination "500". The coded information is visually very difficult to detect when viewing the print pattern 4 in supervision. However, when viewed through the security element 3 according to the invention, the information can be perceived simply and clearly. In addition to the in Fig. 3 when the print pattern 1 is viewed, the mirror-image information of "500" can be seen by looking at the line print pattern 2. The same applies to the subareas 5a, 6a and 5c, 6c and the information that can be read in these subareas.

An exemplary security element is shown in FIG Fig. 5 shown in more detail. The carrier material 30 has an embossed structure with embossed areas 31 and valleys 32 produced by intaglio printing. The embossed structure is designed in the form of a line grid with grid spacing R1. Simultaneously with the embossing structure, the first line printing pattern 1 was printed on the carrier material 30 in the color-guiding intaglio printing. In Fig. 5 three lines 1a, 1b and 1c are shown in cross-section, which in Substantially congruent to the raised areas 31 of the stamping matrix are arranged.

On the back of the carrier material 30, a second line print pattern 2 is arranged, which was applied by offset printing. This is a line grid with the grid size R2, where in Fig. 5 the lines 2a, 2b, 2c and 2d of this grid are shown in cross section. In the case shown, the grid widths of the front and rear grids R1 and R2 match.

In plan view of the line print pattern 1, a line structure can be seen, which stands out due to the use of a dark ink from the bright, pressure-free areas of the substrate 30. In a corresponding manner, the line pressure pattern 2 can also be perceived in a plan view as a sequence of lines 2 a to 2 d executed in dark hue and printing-pressure-free regions of the carrier material 30 that contrast therewith.

As further out Fig. 5 is apparent, the line 2c is offset from the adjacent lines 2b and 2d. The offset is identified by the reference R21. Along the substrate surface, the periodically recurring distance 40 of the lines of the line pressure pattern 2 is reduced by the offset to the distance 41 or increased by the distance 42, which is clearly visible in the area of the line 2c.

From the front side 12 of the banknote 10 or of the security element 3, a sequence of dark print areas and light, pressure-free areas of the carrier material 30 can be perceived by looking through the interaction of the line print patterns 1 and 2. In the area of the front and back line grid 1 and 2, in which lines are not offset from each other, thus results in a regular light / dark contrast in review. In the present case, as viewed from the direction A1, the area S0 appears as a pressure-layer-free region of the front and rear sides of the security element 3 in a light color, which results from the color of the carrier material 30 in transmitted light. On the other hand, the offset of the line 2c causes the observer of the line grid 1, viewed from the direction A1 between the lines 1b and 1c, to perceive a larger, pressure-layer-free area S1. Because of the larger pressure-free area S1, the area between the lines 1b and 1c in the transmitted light from the direction A1 appears brighter than the area between the lines 1a and 1b. The above examples apply mutatis mutandis to a consideration of the lines 2a, 2b and 2b, 2c of the line pressure pattern 2 in the transmitted light from the direction A2.

The offset of the line 2c shows an example of how the staggered arrangement of a plurality of lines of the line pressure pattern 2 information in transmitted light is visible, which is encoded in a plan view of the security element 3 and is not substantially visible.

Out Fig. 5 It can also be seen that the introduction of the embossed structures into the substrate 30 on the second side creates a negative embossing pattern that cooperates with the second line print pattern 2 to yield an optically variable structure. While a sequence of lines and pressure-free regions results in the view from the direction A2 for the viewer, the lines of the line screen 2 are partially obscured or shadowed when viewed from the direction B2, which is why the Hue compared to viewing from A2 changed, and lightened. Accordingly, at least part of the pressure-layer-free regions 40, 41 is masked from the direction C2 by raised regions 33 of the carrier material 30, so that the visual impression from the viewing direction C2 differs from the visual impression that the viewer perceives from the directions A2 or B2 , and darkened. This optically variable tilting effect is relatively pronounced on the back 13 of the banknote 10, while it is practically barely perceptible when viewing the line pressure pattern 1 on the front side 12 of the banknote 10 due to the substantially congruent arrangement of the line grid 1 and the raised areas 31 of the embossed structure , Consequently, from the viewing directions A1, B1 and C1 for the print pattern 1, substantially the same visual impression is obtained for the viewer.

In Fig. 6 FIG. 3 shows a cross section through a security element 3 given as an example, in which a line pressure pattern 1 and 2 is arranged on first and second side of the carrier material 30. While the line printing pattern 2 substantially corresponds to the line printing pattern 2 of the example of FIG Fig. 5 corresponds, the line printing pattern 1 differs significantly from the in Fig. 5 illustrated linear pressure pattern 1. In contrast to the color-guiding intaglio printing of the example according to Fig. 5 , the print pattern 1 of the security element became the Fig. 6 printed in offset printing and combined in a separate process step with an embossing structure in intaglio printing. In this way it is possible to arrange the lines 1a, 1b and 1c of the line grid 1 respectively on one flank of the embossing structure, while the amplitudes 31 remain unprinted. If the grid widths R1 and R2 of the two line grids 1, 2 are chosen to be the same size, substantially similar effects result in transmitted light, as is the case for the example of FIG Fig. 5 described, but with changed distances of the light and dark areas. The latter results directly from the exact arrangement of the lines 1a, 1b, 1c and 2a, 2b, 2c on the carrier material 30th

On the other hand, an optically variable effect of the line pressure pattern 1 on the front side of the security element 3 can now be recognized, since the visual impression differs from the viewing direction A1, B1 and C1. Analogous to the tilting effect of the rear side already described, a change of light, unprinted and dark, printed areas of the carrier material 30 also results for the front-side line pattern 1 from direction A1. The line pattern looks darker from direction B1, while brighter from direction C1. In supervision of the security element 3 of the Fig. 6 Consequently, there is an optically variable effect of the printed patterns 1 and 2 of the first and the second side. Furthermore, in the transmitted light due to staggered lines 2c, the authenticity of the security element 3 characterizing additional information 7 can be seen, as already at Fig. 5 has been described.

Incidentally, the illustrated negative embossing pattern of the second side of the substrate 30 can be reinforced if the printing of the line pattern 2 is supplemented by a so-called blind embossing in intaglio printing.

Furthermore, the back or front line print patterns 2 and 1 can be superimposed or underlaid by an additional translucent, optically variable layer, resulting in further color shift effects on the respective page, depending on the respective viewing direction. Such an additional layer is not shown in the figures for reasons of clarity.

Claims (15)

1. A security element having a transparent carrier material that exhibits, on a first side, a first line print pattern producible from dots or lines and, on a second side, a second line print pattern producible from dots or lines, the first line print pattern being producible from the mirror image of the second line print pattern in that a line print pattern that is substantially a mirror image of the first line print pattern is produced, of which fractional regions are offset with respect to the remainder of the mirror image, and the first line pattern coacting with the second line pattern in such a way that, when looked through, the fractional regions exhibit a piece of visually perceptible information that indicates the authenticity of the security element, characterized in that the first line pattern is a first line grid having a constant line screen,
   in that the first line grid is combined with an embossing pattern that is producible with an intaglio printing method,
   in that the first line grid is a printing layer producible in intaglio printing, the printing layer being arranged substantially congruently to the raised regions of the embossing pattern,
   in that the embossing pattern is a line grid having a constant line screen,
   in that the first line grid and the line grid of the embossing pattern exhibit the same line screen, and
   in that the fractional regions are arranged offset by a fraction of the line screen with respect to the remainder of the mirror image.
2. The security element according to claim 1, characterized in that the embossing pattern of the first side forms, on the second side, a substantially negative embossing pattern that, to form an optically variable pattern, coacts with the second line pattern in such a way that at least portions of the second line pattern are completely visible when viewed vertically, but are hidden when viewed at a slant.
3. The security element according to claim 1 or 2, characterized in that the fractional regions are arranged offset by one third of the line screen with respect to the remainder of the mirror image.
4. The security element according to one of claims 1 to 3, characterized in that the fractional regions form a two-dimensional matrix that exhibits, in a horizontal direction, m fractional regions, and in a vertical direction, n fractional regions, where m, n ≥ 1, preferably m, n ≥ 2 applies.
5. The security element according to claim 4, characterized in that the fractional regions are arranged offset by different fractions of the line screen with respect to the remainder of the mirror image.
6. The security element according to at least one of claims 1 to 5, characterized in that the second line pattern is a printing layer producible in intaglio, offset, screen, flexo, xerographic, inkjet or thermographic printing or by a laser printer.
7. The security element according to at least one of claims 1 to 6, characterized in that the first line grid and/or the second line pattern is a portion of an image motif or geometric pattern arranged on the first or second side.
8. The security element according to at least one of claims 1 to 7, characterized in that the first line grid and/or the second line pattern is an at least partially multicolored layer.
9. The security element according to at least one of claims 1 to 8, characterized in that the first line grid and/or the second line pattern is formed from an optically variable printing ink or a metallic effect ink.
10. The security element according to at least one of claims 1 to 9, characterized in that at least one side of the security element exhibits an additional translucent, optically variable layer or a foil element.
11. The security element according to one of claims 1 to 10, characterized in that the piece of visually perceptible information of the fractional regions is an alphanumeric character, symbol and/or geometric pattern.
12. The security element according to at least one of claims 1 to 11, characterized in that the carrier material is paper, especially a cotton-vellum paper, or a plastic foil, especially a foil composed of PET (polyethylene terephthalate), PBT (polybutylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PA (polyamide) or PE (polyethylene).
13. A data carrier having a security element according to one of claims 1 to 12, the data carrier preferably being a security paper, especially a banknote.
14. A method for manufacturing a security element having a transparent carrier material, in which, on a first side, a first line print pattern produced from dots or lines is imprinted and, on a second side, a second line print pattern produced from dots or lines is imprinted, the second line print pattern being producible from the mirror image of the first line print pattern in that a line print pattern that is substantially a mirror image of the first line print pattern is produced, of which fractional regions are offset with respect to the remainder of the mirror image, and the first line pattern coacting with the second line pattern in such a way that, when looked through, the fractional regions exhibit a piece of visually perceptible information that indicates the authenticity of the security element, characterized in that the first line pattern is a line grid having a constant line screen, in that, in an intaglio printing method, an embossing pattern is produced and is combined with the first line grid,
    the first line grid and the embossing pattern being produced simultaneously in an intaglio printing method such that the first line grid is arranged substantially congruently to the raised regions of the embossing pattern,
    in that the embossing pattern is produced as a line grid having a constant line screen, the first line grid and the line grid of the embossing pattern being produced having the same line screen, and in that the fractional regions are produced to be offset by a fraction of the line screen with respect to the remainder of the mirror image.
15. The method according to claim 14, characterized in that the second line pattern is produced in planographic printing, such as in the offset method, in relief printing, such as in letterpress printing or in the flexographic printing method, in screen printing, in gravure printing, such as in photogravure printing or in intaglio printing, in an inkjet or thermographic method, such as in the thermotransfer method, or in laser printing.

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