AU2011348479A1

AU2011348479A1 - Optically variable element, in particular a security element for a data storage medium

Info

Publication number: AU2011348479A1
Application number: AU2011348479A
Authority: AU
Inventors: Peter Franz; Christian Fuhse; Thanh-Hao Huynh
Original assignee: Giesecke and Devrient GmbH
Current assignee: Giesecke and Devrient Currency Technology GmbH
Priority date: 2010-12-20
Filing date: 2011-12-16
Publication date: 2013-06-20
Anticipated expiration: 2031-12-16
Also published as: EP2655081A1; AU2011348479B2; WO2012084169A1; EP2655081B1; DE102010055236A1

Abstract

The invention relates to an optically variable element, in particular a security element for a data storage medium, having a substrate (6) comprising a reflective layer (7), which is provided with a pattern-forming surface structure having a first and a second sub-region (4, 5), wherein the two sub-regions (4, 5) can each be optically perceived as protruding and/or receding, respectively, the optically perceptible and the haptically detectable impressions of the first sub-region (4) agree with each other, and the optically perceptible and the haptically detectable impressions of the second sub-region (5) do not agree with each other.

Description

- I Optically variable element, in particular security element for a data carrier [0001] This invention relates to an optically variable element, in particular security element for a data carrier. [0002] Data carriers, such as value documents, identity documents, or objects of value, such as branded articles, are often provided for safeguarding purposes with an optically variable element which permits a check of the authenticity of the data carrier and which at the same time serves as protection from unauthorized reproduction. For this purpose, the optically variable element has an optical effect that varies for example upon a change of viewing direction and that cannot be copied with conventional copiers. [0003] On these premises, the invention is based on the object of stating an optically variable element, in particular a security element for a data carrier, which combines high forgery-proofness with good recognizability and easy verifiability. [0004] This object is achieved by an optically variable element, in particular a security element for a data carrier, having a substrate comprising a reflective layer having a motif-forming surface structure with a first and a second partial region, the two partial regions being optically perceptible respectively as protruding and/or receding, the optically perceptible and the haptically detectable impressions of the first partial region matching, and the optically perceptible and the haptically detectable impressions of the second partial region not matching. [0005] There is thus provided an optically variable element which is optically very attractive due to the optically protruding and/or receding partial regions, and wherein the haptically detectable impression surprisingly matches the optically perceptible impression only for the first partial region and not for the second partial region. This variation of the haptic and thus palpable perception of the motif produces a high recognition value and leads to easy verifiability of the authenticity of the optically variable element.

-2 [00061 A partial region that is optically perceptible as protruding and/or receding is understood here to mean in particular that the corresponding partial region is perceptible as a continuously bulged area. Thus, the partial region can be perceived optically with a bulge that deviates from the curvature or actual spatial form of the reflective layer in the region of the corresponding partial region. In particular with the second partial region it is e.g. possible to imitate an accordingly bulged surface by simulating the corresponding reflection behavior. [0007] The two partial regions can be respectively configured as a contiguous region. It is also possible, however, that the partial regions have gaps or even comprise non-contiguous portions. In particular, the two partial regions can be interlaced with each other and/or with other security features. [0008] Further, one of the two partial regions can surround the other of the two partial regions. [00091 In the optically variable element, the motif-forming surface structure can be embossed. This is advantageous e.g. in that such an optically variable element is easy to manufacture. In particular, the embossing can be carried out by means of gravure printing (without ink) and thus as a so-called blind embossing. [0010] Further, in the optically variable element according to the invention, the motif-forming surface structure can have in the second partial region a multiplicity of reflective facets which are so oriented that there is optically perceptible to a viewer a reflective area that protrudes and/or recedes relative to the macroscopic spatial form of the reflective layer in the second partial region. With the second motif region there can thus be imitated a real bulged reflective surface. It is also possible, however, to simulate with the second motif region a reflective areal form whose reflection behavior cannot be produced with a real bulged surface. Thus, the second partial region of the security element according to the invention can be configured e.g. so as to be perceptible to a viewer as an imaginary area. For example, such an imaginary area can be perceptible as a rotating mirror which rotates the visible mirror image e.g. by 900.

-3 Such an imaginary area and in particular such a rotating mirror is very easy for a viewer to detect and to verify. [00111 In principle, any real bulged reflective or transmissive surface can be modified to an imaginary area by means of the second partial region of the security element according to the invention. This can be realized e.g. by changing the azimuth angles of all facets, for example rotating them by a certain angle. This enables interesting effects to be achieved. When all azimuth angles are rotated to the right by 450 for example, an areal region is a bulged area that is apparently illuminated from the top right for a viewer when illuminated directly from above. When all azimuth angles are rotated by 900, the light reflexes move upon tilting in a direction perpendicular to the direction that a viewer would expect. This unnatural reflection behavior then for example also makes it impossible for a viewer to decide whether the area perceptible as bulged goes forwards or backwards (relative to the areal region). [0012] Advantageously, the reflective area can also be perceptible to a viewer as a non-planar area. [0013] Further, in the optically variable element according to the invention, the orientations of several facets can be changed relative to the orientations for producing the protruding and/or receding reflective area such that the protruding and/or receding reflective area is still perceptible but with a surface appearing matt. Also, in the optically variable element according to the invention, the orientations of several facets can be changed relative to the orientations for producing the protruding and/or receding reflective areas such that the protruding and/or receding reflective area is still perceptible but as a surface with a glitter effect, i.e. as a glittering surface. For producing such a matt or glittering surface the procedure is as follows: The change of the orientations of several facets is given by a random deviation from a specified target orientation within certain limits. In particular, several neighboring facets can also deviate from the target orientation by the same respective random deviation. Depending on the size of the random deviation and size or number of the facets with the same respective deviation there can thus be produced for example a surface -4 appearing matt or also a glittering surface, i.e. surface with a glitter effect. Such security elements having a surface reflecting matt or a glittering surface have a very high recognition value and thus very high forgery-proofness. [0014] Further, in the optically variable element, the facets can be configured as achromatic facets. This is understood to mean in particular that the reflection behavior of the facets is determined or at least dominated by ray-optical effects. The facets thus do not act as a diffractive structure, or only hardly. t0015] In the optically variable element, the highest facets can have a minimum height of 10 pm. In particular, the height of the highest facets lies in the range of 10 pm to 300 jim, preferably 15 im to 200 pm, further preferably 20 pim to 120 jim, and particularly preferably 25 jim to 110 jim. The above specification of the highest facets takes account of the fact that the facets of the security element according to the invention normally vary within the second partial region. In a very particularly advantageous embodiment it is further preferred in such a security element that substantially all facets have a minimum height of 10 jim, and in particular the height of the facets lies in the range of 10 [tm to 300 jm, preferably 15 jim to 200 jim, further preferably 20 jim to 120 jm, and very particularly preferably 25 jim to 110 pm. All facets having the above-mentioned (highest) heights greater than 10 pm can be precisely fabricated by the method according to the invention and hence have very high forgery-proofness. [00161 The facets can be configured with a spatial frequency of 5 to 500 facets/cm, preferably 10 to 300 facets/cm, and particularly preferably 20 to 150 facets/cm. The lateral dimension of the facets can preferably lie in the range of 10 jim to 500 jim, particularly preferably 20 jim to 180 jim, and in particular 30 jim to 150 jm. [0017] The embossing distance of the two partial regions can lie between 0 jim and 500 pim, preferably between 0 jim and 150 jim, and particularly preferably between 0 tm and 50 jm.

-5 [0018] The spatial frequency of the facets as well as the height of the facets can be constant or also vary in the second partial region. Particularly preferable here are facets that are arranged periodically or at least locally periodically with a constant period. Particularly preferable are also facets whose height changes substantially continuously in the second partial region. [0019] In any case, the dimensions of the facets are so chosen that the optically detectable impression of the second partial region does not match the tactile or palpable impression of the second partial region. [0020] The structure sizes of the motif-forming surface structure for the first partial region can have substantially the same single dimensions as the facets. In particular, the motif-forming surface structure can contain in the first partial region line-shaped embossed elements arranged substantially parallel. The line density can amount to approx. 10 lines/cm to 1000 lines/cm, preferably 20 lines/cm to 300 lines/cm and very particularly preferably 40 lines/cm to 150 lines/cm. [0021] The dimensions of the surface structure are in any case so chosen that the haptic impression matches the optical one. This can be adjusted in particular via the aspect ratio (height of corresponding embossed structure to width of embossed structure). Particularly preferable aspect ratios are in the range of approx. 1: 4 to approx. 4: 1. The aspect ratio for the second partial region also preferably amounts to approx. 1: 4 to approx. 4: 1 and is so chosen in terms of absolute sizes that the optical impression does not match the haptic impression. [0022] It is particularly preferable when the maximum height of the surface structure in the first partial region is greater than the maximum height of the surface structure in the second partial region. In particular, the maximum height in the first partial region can amount to at least 30 pm and preferably at least 50 Rm. [0023] The reflective layer can be configured as a metal layer. The material employed can be for example aluminum, silver, copper, chromium, iron and/or another -6 metal or alloys thereof. The reflective layer can also be provided as a metal foil which is applied to the substrate. [0024] The reflective layer can be configured as a single layer or also in multi-ply form. Further, it can have effect pigments. [0025] Furthermore, it can contain a further security feature, such as e.g. a machine-readable feature. This may be e.g. aligned magnetic pigments. [0026] The optically variable element can be configured in particular as a security thread, tear thread, security band, security strip, patch or as a label for application to a security paper, value document or the like. In particular, the optically variable element can span transparent or at least translucent regions or recesses. [0027] The term security paper is understood here to be in particular the not yet circulable precursor to a value document, which can have besides the security element of the invention for example also further authentication features (such as e.g. luminescent substances provided within the volume). Value documents are understood here to be, on the one hand, documents manufactured from security papers. On the other hand, value documents can also be other documents and objects that can be provided with the optically variable element according to the invention in order for the value documents to have uncopiable authentication features, thereby making it possible to check authenticity and at the same time preventing unwanted copying. [0028] There is further provided a data carrier having an optically variable element according to any of the above claims. The data carrier may be a value document, identity document, security paper or other object of value. [0029] There is further provided a method for manufacturing the optically variable element according to the invention (including its developments) wherein the reflective layer is applied to the substrate and thereafter the motif-forming surface structure is produced (permanently) by blind embossing.

-7 [00301 Thus, it is easy to manufacture the optically variable element according to the invention in large numbers. [0031] In particular, the two partial regions are embossed in a single embossing step, there preferably being employed for this purpose only a single embossing die. This facilitates the manufacture. [0032] Further, there is provided a method for manufacturing a data carrier having an optically variable element according to the invention (including its development) wherein the optically variable element is provided on and/or in the data carrier. [0033] In so doing, the reflective layer can be formed on the data carrier and thereafter the motif-forming surface structure be embossed into the reflective layer. Preferably, the two partial regions are embossed in a single embossing step. For this purpose there can be employed e.g. a single embossing die. [0034] The embossing step preferably involves gravure printing without ink and thus a so-called blind embossing. [0035] Further, the optically variable element can first be partly manufactured by only one of the two partial regions being formed. In this case the partly manufactured optically variable element is connected to the data carrier and thereafter the lacking partial region formed. At least one of the two partial regions can be formed by embossing (in particular blind embossing). [0036] There is further provided an embossing die having an embossing area with which the motif-forming surface structure of the optically variable element according to the invention (including its development) can be embossed. [0037] The embossing area can be produced e.g. by material removal by means of laser radiation. For this purpose it is preferable to use pulse-operated lasers, preferably in particular picosecond lasers. The use of laser radiation enables a very high resolution to be obtained. In particular, the aspect ratio can be formed considerably higher in comparison to classical manufacturing methods for embossing dies.

-8 [0038] As the material for the substrate of the security element and/or for the data carrier (such as e.g. a bank note) there can be employed a plastic material. In particular, a paper substrate is also possible. [0039] Thus, there can be used paper with synthetic fibers, i.e. paper with a content x of polymeric material in the range of 0 < x < 100 wt.%, a plastic foil, e.g., a foil of polyethylene (PE), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polypropylene (PP) or polyamide (PA), or a multilayer composite, in particular a composite of several different foils (compound composite) or a paper-foil composite (foil/paper/foil or paper/foil/paper). The optically variable element can be provided in, on or between each of the layers of such a multilayer composite. [0040] It will be appreciated that the features mentioned hereinabove and those to be explained hereinafter are usable not only in the stated combinations but also in other combinations or in isolation without going beyond the scope of the present invention. In particular, the optically variable element can have all features that are produced in the described manufacturing method for producing the optically variable element. Also, the method for manufacturing the optically variable element can be so developed that all described examples and embodiments of the optically variable element can be manufactured. The same applies to the described data carrier and the description for manufacturing methods for such a data carrier. The embossing die according to the invention can be so developed that each optically variable element described herein is manufacturable. 100411 Hereinafter the invention will be explained more closely by way of example with reference to the attached drawings, which also disclose features essential to the invention. For clarity's sake, the representation in the figures is not true to scale or to proportion. There are shown: Fig. 1 a plan view of a bank note having an optically variable element 1 according to the invention; -9 Fig. 2 an enlarged sectional view of the optically variable element I along the sectional line A-A in Fig. 1; Figs. 3A - 3D steps for explaining the manufacture of the optically variable element according to Figs. 1 and 2; Fig. 4 a schematic plan view of a further embodiment of the optically variable element according to the invention, Fig. 5 a schematic plan view of a further embodiment of the optically variable element according to the invention, and Figs. 6A - 6B a schematic plan view of yet a further embodiment of the optically variable element according to the invention at two different viewing angles. [00421 In the embodiment shown in Fig. 1, the optically variable element 1 according to the invention is applied to the front side, shown in Fig. 1, of a bank note 2 and serves as a security element or security feature in order to enable the authenticity of the bank note 2 to be examined. [0043] The optically variable element or security element 1 is configured as a reflective security element 1 with a rectangular outside contour, and has a motif 3 having a first partial region 4 and a second partial region 5 which in this case is surrounded by the first partial region 4. The first partial region 4 forms a circular edge for the second partial region 5. [0044] As can be seen best in Fig. 2, which schematically shows a section of the security element 1 along the line A-A, the security element 1 comprises a substrate 6 with a reflective layer 7. The upper side of the reflective layer 7 facing away from the substrate 6 is embossed and hence has a surface structuring, but the latter is configured differently in the first and second partial regions 4, 5.

- 10 [0045] In the first partial region 4 the surface structuring is configured as an elevation 8 having two flanks 9, 10 and a rounded peak 11 connecting the two. The height of the elevation is dl here, with the height dl and the lateral dimension (maximum distance of the two flanks 9, 10 in the sectional view according to Fig. 2) of the elevation 8 being so chosen that the first partial region 4 is perceptible optically as an elevated ring and the haptically detectable impression matches this. [0046] In the second partial region 5 the embossing is so configured as to provide a multiplicity of reflective facets 12 which simulate for a viewer a reflective area 13 which appears bulged relative to the actual macroscopic spatial form of the reflective layer 7 in the second partial region 5. In the embodiment described here, the reflective area 13 is a portion of a sphere, as indicated in the sectional representation in Fig. 2 by the dashed line with the reference sign 13. [0047] This optical effect is obtained by the inclination of the facets 12 being so chosen that incident light on the facets 12 is reflected in the same direction in which a bulged area 13 would reflect the light. [0048] Thus, the incident light ray 15 is reflected in direction 16 which is parallel to the direction 16' that would correspond to the direction of reflection on the surface 13. The same applies to the light rays 17 and 19, which are reflected in the directions 18 and 20. These directions 18 and 20 are parallel to the directions 18' and 20' that would be the reflection directions upon reflection on the surface 13. [0049] The maximum height d2 and the maximum dimension of the facets 12 are preferably so chosen that an observer cannot resolve the facets 12 with the unarmed eye. The preferred embodiment shown in Fig. 2 has facets that are arranged periodically with a substantially constant period. Also, the facets of this embodiment have a height that increases substantially continuously from a middle region of the second partial region toward an outer region of the second partial region, i.e. toward the first partial region, and reaches the maximum height d2 there.

- 11 [0050] From the reflection behavior of the second partial region 5 a viewer hence infers that in the second partial region 5 the bulged surface 13 is present with a height d3 that is considerably greater than the maximum height d2 of the facets 12. Thus, for example for the light ray 15 the reflection behavior suggests that the local surface normal points in direction 21, which is clearly different from the macroscopic surface normal (arrow 22) of the reflective layer 7 in the second partial region 5. In the second partial region 5 a bulge is thus imitated by directional reflection on the facets 12, thereby resulting only indirectly in an impression of depth or a 3D impression. This impression can hence also be designated as a "2 1/2"-dimensional representation or relief-like representation. [0051] Due to the small dimensions of the individual facets 12, the haptically detectable impression of the second partial region differs clearly from the optically perceptible impression. Thus, a viewer will expect a forwardly bulged area on the basis of the optical impression. When touching the second partial region 5, however, he will finger or feel substantially only a plane area. [0052] While the optically perceptible impression thus matches the haptic perception in the first partial region 4, the optically perceptible impression and the haptically detectable impression diverge in the second partial region 5. Thus, the security element 1 according to the invention is advantageously verifiable easily and unambiguously for the user without additional auxiliary means. [0053] The optically variable element 1 according to the invention can be manufactured as follows. First, a metal layer as a reflective layer 7 is formed by vapor deposition on the substrate 6, which can be configured for example as a plastic foil (step from Fig. 3A to Fig. 3B). [00541 Thereafter the desired surface structure is embossed with a gravure printing plate 25 into the upper side of the reflective layer 7 and thus of course also into the substrate 6, with the two partial regions 4 and 5 of the motif 3 being embossed with the one gravure printing plate 25 in a single method step (step from Fig. 3C to Fig. 3D).

-12 [0055] The structuring of the upper side of the reflective layer 7 for forming the first and second partial regions 4, 5 of the motif 3 can thus be produced by means of blind embossing in a single step. Hence, the motif 3 can be easily manufactured e.g. under the machine and speed specifications of a typical security printing plant. [0056] The thus manufactured optically variable element 1 can then be applied to the upper side of the bank note 2 in order to manufacture the bank note 2 according to Fig. 1. [0057] It is of course also possible to form the reflective layer 7 not on the substrate 6, but directly on the upper side of the bank note 2. In this case the bank note 2 is the substrate for the reflective layer 7. The already (partly) finished bank note 2 (with the reflective layer 7) can then be subjected to the gravure printing step according to Fig. 3C and Fig. 3D in order to permanently manufacture the desired motif 3 by embossing. [0058] Further, it is possible to first manufacture the optically variable element 1, in which case the latter only has the first or second partial region 4, 5, however. This partly finished optically variable element 1 is then applied to the bank note 2, and thereafter the lacking partial region 4 or 5 is formed in a separate gravure printing step. [0059] When the reflective layer 7 is configured as a metal layer, there can be employed as a material for example aluminum, silver, copper, chromium, iron and/or another metal or alloys thereof. [00601 The reflective layer can not only be configured as a single layer, as hitherto described, but can also be multi-ply and/or have effect pigments. The substrate can also be single- or multi-ply. [0061] Further, the reflective layer 7 can be realized by a printing method wherein e.g. a silver ink and/or gold ink is applied to the substrate 6. As a printing method there can be used known printing methods, such as e.g. screen printing, offset printing or indirect printing. Flexographic printing methods are also possible. Furthermore, the reflective layer 7 can be present as a foil which is applied to the substrate 6. Besides - 13 the metallic inks already mentioned by way of example, there can also be used Iriodins (trade name of pearl luster pigments from Merck) or pearl luster inks. Furthermore, there can be used so-called effect inks with effect pigments. These may e.g. be effect pigments manufactured on the basis of liquid crystal polymers, said pigments being translucent taken alone. In this case the effect pigments are arranged on a corresponding reflective layer on the substrate. [0062] Furthermore, there can be used the effect pigments described in WO 2009/074284 A2. [0063] So-called thin-film pigments which show different colors in a viewing angle-dependent manner due to interference effects can also be used. Furthermore, the effect pigments can be self-reflective when being configured for example as metal pigments. [0064] In Fig. 4 there is shown a further embodiment of the optically variable element 1 according to the invention wherein the first partial region represents the number 5 six times in an optically elevated form and also palpably in this form. The second partial region 5 has rhombi appearing three-dimensional optically but not being palpable in this three-dimensional form, being rather palpable only as a plane area. [0065] In Fig. 5 there is shown a further embodiment of the optically variable element 1 according to the invention, the motif in this case being intended to be a portrait, which is shown very schematically here. In this portrait, individual parts can bc configured as the first partial region 4, such as e.g. the nose and mouth. The remaining parts of the portrait are then configured as the second partial region 5. [0066] Finally, there is shown in Fig. 6 yet a further embodiment of the optically variable element according to the invention. The embodiment of Fig. 6 differs from the embodiment shown in Fig. 5 only in that the second partial region 5 of the portrait has an additional information item, in this case the number "50". The number "50" may be e.g. the denomination number of the object of value to be protected by the optically variable element. However, there might ultimately also be used any other information, -14 e.g. in the form of an alphanumeric character, a logo, a geometrical shape, etc. The additional information item is designated in Fig. 6A and Fig. 6B with the reference sign 30. [00671 There follows a closer treatment of the structure, manufacture, and pictorial impression resulting for the viewer, of the additional information item 30. [0068] As mentioned above, the motif-forming surface structure according to the invention on the optically variable element 1 is advantageously obtained by embossing. Hence, it is also preferred with reference to Fig. 6A and Fig. 6B to produce the additional information item 30 by embossing a reflective area. For example, the additional information item 30 can be formed by a multiplicity of facets and/or sawtooth structures with constant orientation. Upon viewing of the optically variable element 1 at a first viewing direction and with a defined illumination direction, which is produced e.g. by a light source, the additional information item 30 appears to the viewer with a first brightness value. As shown in Fig. 6A, the viewer perceives from the first viewing direction for example the bright denomination number "50". The other regions of the optically variable element according to the invention, in particular the first partial region 4 and the second partial region 5, are likewise perceived by the viewer from the first viewing direction with the first brightness values associated with the respective regions. [0069] When the optically variable element 1 is tilted relative to the viewer at a fixed illumination direction, or when the viewer changes his viewing direction relative to the optically variable element 1, he will perceive a change in the brightness of the additional information item 30. For example, for the observer's second viewing direction the additional information item recognizable to him is represented as a dark denomination number "50". The change in the brightness of the denomination number "50" upon a change of viewing direction can be determined by the arrangement of the sawtooth structures with constant orientation, in dependence on a specified illumination direction. That is to say, the denomination number "50" changes its brightness for the viewer, at a specified illumination direction, upon tilting of the - 15 security element or upon a change of the observer's viewing direction relative to the security element in an intended way. The different brightness impressions for the viewer are achieved by shadow effects, i.e. at a specified illumination direction the light is partly shadowed, i.e. reflected away from the viewer, by the sawtooth structures upon tilting of the optically variable security element or upon a change of viewing direction, so that the observer perceives a darker brightness impression than without shadowing. It will be appreciated that the other regions 4, 5 of the optically variable element can likewise be perceived by the viewer with different first and second brightnesses from the different viewing angles according to Fig. 6A and Fig. 6B. At a given viewing direction and illumination direction, the embossed structures of the optically variable security element, in particular in the second partial region 5, and in the region of the additional information item 30, can also be chosen, however, such that the additional information item appears approximately with the same brightness as the surrounding optically variable security element, so that the additional information item is substantially unrecognizable under these illumination and viewing conditions. The pictorial impression perceptible to the viewer in such a variant then corresponds substantially to the pictorial impression shown in Fig. 5, because the information item 30 does not stand out from the rest of the security element in a contrasting manner. The additional information item can be perceived by the viewer, at a given illumination direction, normally by simple tilting of the security element or else upon a change of viewing direction relative to the security element, and thus constitutes an additional security feature which further increases the forgery-proofness of the optically variable element I and also the optical attractiveness of the security element according to the invention for the viewer. [00701 Besides the embodiment shown in Fig. 6 with only one additional information item in the form of the denomination number "50", the additional information item can of course also have several parts. For example, there could also be provided besides the denomination number "50" a further symbol, for example a euro sign ("6"). For the region of the euro sign there would then be provided sawtooth structures with a multiplicity of sawteeth with an orientation differing from the - 16 orientation of the sawtooth structures in the region of the denomination number "50". Upon viewing at a first viewing angle the denomination number "50" could then appear bright according to Fig. 6A and the euro sign dark, while upon viewing of the security element at a second viewing angle the denomination number "50" appears dark according to Fig. 6B while the euro sign appears bright to the viewer under these observation conditions. Furthermore, it is also conceivable that the additional information item is formed from e.g. two regions which are arranged in overlap. For this purpose, the sawtooth structure of the discussed example with the denomination number "50" and with the euro sign could be configured such that the sawtooth structure associated with the denomination number "50" and the sawtooth structure associated with the euro sign are interlaced, which is effected e.g. by a strip- or pixel shaped breakdown of the total region of the additional information item and alternating arrangement of a strip/pixel with sawtooth structures of the denomination number "50" and of the euro sign. The strips or pixels respectively associated with the denomination number "50" and the euro sign can have an extension, in particular strip width, of e.g. 100 gim. Through such an overlapping arrangement of two regions of the additional information item there can be provided a security element with exceptionally high protection from forgery and optical attractiveness, because the effects of optical perception and haptic detectability according to the invention are supplemented by the further effect of the additional information item. [0071] With regard to the additional information item, it should be noted that it can also be arranged in a multiple manner, with the sawtooth gratings within an arrangement having sawteeth with a fixed orientation, and this orientation differing from the orientation of the other representations. Upon tilting of the security element with such a multiply arranged, additional information item there occurs for the viewer a so-called "kinematic effect", i.e. the viewer can perceive in the above-mentioned example with the denomination number "50" an additional information item 30 which, upon tilting, seems to move over the optically variable element and thereby also changes its brightness (running effect).

- 17 [0072] Finally, it should be mentioned that the structure with e.g. embossed sawtooth gratings or embossed facets provided for the additional information item can be produced either subsequently in an additional embossing step or else especially advantageously at the same time as the embossing of the first and second partial regions of the optically variable element. In such a case the gravure printing plate 25 shown with regard to Fig. 3 would have corresponding engravings which are required for producing the sawtooth structures or facets. In the embossing step the structures of the first partial region, of the second partial region and of the additional information item would then be incorporated into the substrate of the security element at the same time.

- 18 List of reference signs 1 Optically variable element 2 Bank note 3 Motif 4 First partial region 5 Second partial region 6 Substrate 7 Reflective layer 8 Elevation 9 Flank 10 Flank 11 Peak 12 Facet 13 Reflective area 15 Light ray 16, 16' Direction 17 Light ray 18, 18' Direction 19 Light ray 20, 20' Direction 21 Direction 22 Arrow 25 Embossing die 26 Embossing area 30 Additional information item

Claims

1. An optically variable element, in particular security element for a data carrier, having a substrate (6) comprising a reflective layer (7) having a motif-forming surface structure with a first and a second partial region (4, 5), the two partial regions (4, 5) being respectively perceptible optically as protruding and/or receding, the optically perceptible and the haptically detectable impressions of the first partial region (4) matching, and the optically perceptible and the haptically detectable impressions of the second partial region (5) not matching.

2. The optically variable element according to claim 1, wherein the motif-forming surface structure is embossed.

3. The optically variable element according to claim 1 or 2, wherein the motif forming surface structure has in the second partial region (5) a multiplicity of reflective facets (12) which are so oriented that there is optically perceptible to a viewer a reflective area (13) which protrudes and/or recedes relative to the macroscopic spatial form of the reflective layer (7) in the second partial region (5).

4. The optically variable element according to claim 3, wherein the reflective area (13) is perceptible to a viewer as a non-planar area.

5. The optically variable element according to claim 3 or 4, wherein the orientations of several facets (12) are so changed relative to the orientations for producing the protruding and/or receding reflective area (13) that the protruding and/or receding reflective area (13) is still perceptible but with a surface appearing matt and/or glittery.

6. The optically variable element according to any of claims 3 to 5, wherein the facets (12) are so oriented that the second partial region (5) shows a reflection behavior that cannot be produced with a real macroscopically bulged reflective surface. - 20

7. The optically variable element according to any of claims 3 to 6, wherein the facets (12) are configured as achromatic facets (12).

8. The optically variable element according to any of claims 3 to 7, wherein the highest facets (12) have a minimum height of 10 ptm and preferably a height of 25 jim to 110 jim.

9. The optically variable element according to any of claims 3 to 8, wherein the facets are arranged periodically or at least locally periodically with a constant period.

10. The optically variable element according to any of the above claims, wherein the maximum height of the surface structure in the first partial region (4) is greater than the maximum height of the surface structure in the second partial region (5).

11. The optically variable element according to claim 10, wherein the maximum height in the first partial region (4) amounts to at least 30 pim and preferably at least 50 jim.

12. A data carrier having an optically variable element according to any of the above claims.

13. A method for manufacturing the optically variable element according to any of claims 1 to 11, wherein the reflective layer (7) is applied to the substrate (6) and thereafter the motif-forming surface structure is produced by blind embossing.

14. The method according to claim 13, wherein the two partial regions (4, 5) are embossed in a single embossing step, there preferably being employed for this purpose a single embossing die.

15. A method for manufacturing a data carrier having an optically variable element according to any of claims 1 to 11, wherein the optically variable element is provided on and/or in the data carrier. - 21

16. The method according to claim 15, wherein the reflective layer is formed on the data carrier, and thereafter the motif-forming surface structure is embossed into the reflective layer.

17. The method according to claim 16, wherein the two partial regions (4, 5) are embossed in a single embossing step.

18. The method according to claim 15, wherein the optically variable element is first partly manufactured by only one of the two partial regions being formed, the partly manufactured optically variable element being connected to the data carrier, and thereafter the lacking partial region being formed.

19. The method according to claim 18, wherein the two partial regions are respectively formed by embossing.

20. An embossing die having an embossing area with which the motif-forming surface structure of the optically variable element according to any of claims 1 to 11 can be embossed.