WO2001029764A1

WO2001029764A1 - Data carrier comprising authentication tags and a production method therefor

Info

Publication number: WO2001029764A1
Application number: PCT/EP2000/010069
Authority: WO
Inventors: Frank Kappe; Benedikt Ahlers; Arnim Franz-Burgholz; Hermann Hecker
Original assignee: Bundesdruckerei Gmbh; Orga Kartensysteme Gmbh
Priority date: 1999-10-16
Filing date: 2000-10-13
Publication date: 2001-04-26
Also published as: DE19949945A1; AU1024601A

Abstract

The invention relates to a card-type data carrier, consisting of laminated layers. According to the invention, visually irreversible modifications (elements 8, 9) are made to the interior of the data carrier using a laser beam (28, 29), in such a way that different graphic images can be recognised when viewed from different angles of vision (25, 26) and that they can be used to verify the authenticity of the data carrier. The invention also relates to a production method for a data carrier of this type.

Description

Data carriers with authenticity features and manufacturing processes therefor.

The invention describes a data carrier consisting of various laminate layers, in which visually irreversible changes in the interior of the data carrier are brought about by means of a laser beam in such a way that when viewed from different perspectives, different graphic structures are recognizable and can be used to verify the authenticity of the data carrier and manufacturing processes thereof.

description

The present invention relates to a novel method and an inexpensive method for laser processing systems for producing wiggle-like effects on laminate composites with generally transparent or translucent cover foils.

EP 0 216 B1 and EP 0 219 012 B1 describe the basic principles of such methods and processes, a polycarbonate film composite of several thin films with security prints in between being produced by lamination in the usual credit card format. The authenticity features are written into the card network by means of a laser beam. Here, a top of the card is provided with a so-called lens grid in a melting process in a thermal transfer press. The upper edge of the lens grid is preferably arranged in one plane with the card body, so that the lens surface is protected to a certain extent. The lenses of the lenticular screen formed in this way now direct a laser beam in an oblique orientation to the card surface, which is focused in the area of the respective lens and directed onto a specific inner plane of the card. At this level, defined darknesses are created - as an authenticity feature. In this way, at least two authenticity features, which are dependent on the viewing direction of the observer, can be written into the card.

The usual lens diameters can be calculated very easily on the basis of the refractive indices of thermoplastics that are available and technically possible, and lens diameters of approximately 250 to 400 micrometers are usually used, which are arranged in a grid shape next to one another in a cylindrical shape. Grid distances are used which are slightly below the lens diameter, so that the lenses partially overlap in the edge area. This results in embossing depths of typically 70 to 100 micrometers. With a refractive index of approximately 1.5, the irreversible and visible material changes lie at a depth of, for example, 200 to 450 micrometers in the card network and are therefore well protected against mechanical damage and counterfeiting.

European Patent EP 0 219 012 B1 now further states that the change in the optical properties is limited to areas (pixels) whose radial extent is smaller than the diameter of a single lens, and that the information that is obtained using laser beams were recorded from at least two different directions in the lenticular area, can be read under the same directions in limited angular ranges and / or recorded by measurement.

A disadvantage of the production of such lenticular screens is the fact that a relatively deep embossing during the lamination process - cf. EP 0 842 791 A2 - and / or even more complex in the single card - cf. EP 0 843 281 A2 - has to be carried out, in the single card in general the already graphically designed and laminated card generally results in a relatively strong distortion or a strong material flow due to the material displacement to form the lens grid.

In the case of stamping by means of press plates in a multi-day thermal transfer press, it must also be taken into account that such stamping press plates are extremely expensive and the entire process is therefore very expensive.

The object of the invention is accordingly a simplification of the embossing process of any customer-specific designed lenticular structure to achieve a comparable or improved wiggle effect due to laser processing and an additional increase in the complexity of the method and thus increase the difficulty of counterfeiting such a wiggle-like effect.

This object is achieved by a method according to the technical teaching of claim 1, which has the main content that the laser inscription of the card takes place in a first process step without the aid of a lens grid and that the lens grid is applied only in a second process step becomes. According to the invention, there is therefore a different order in which the authenticity features are introduced into the card, because the authenticity features are first written in and then the lens system is only generated in order to ensure a reading that is separate according to the viewing direction.

According to the invention, the lens system is therefore no longer used to write in the authenticity features. This has the advantage that the cards are labeled with the two (or more than two) different authenticity features in a relatively simple labeling process and that the lens system is only subsequently generated when the card is finally finished.

According to the invention, the necessary information is thus introduced into the card body without a surface relief or without an optical lens effect in such a way that the information previously introduced is optically recognized or measured by at least two different directions from a viewer and / or from a technical point of view through a subsequent application of appropriately coordinated surface reliefs or optical lens effects can be detected.

According to the subsequently applied surface relief and its optical lens effect, two or more different pieces of information, which were placed in close proximity by means of a laser in the interior of a laminate composite, can be recognized or read out. Three fundamentally new methods and processes are described for the production of these surface reliefs.

Such a method therefore does not require a laser beam from at least two different directions, as mentioned in the documents EP 0216947 B1 and EP 0 219 012 B1, but rather the closely adjacent information can be juxtaposed in the desired depth by means of a very small laser beam focusing or location can be arranged. The subsequently applied surface relief must therefore be applied in the correct position so that the focal point of the optical lenses enables the information generated by laser beams to be recognized and read out. The precise application of the lenticular grid is not of crucial importance. If the lenticular array is only applied offset to the laser image underneath, the readout will only change the direction of readout. One image can then possibly only be recognized from a viewing angle of 40 degrees to the card surface, while the other image can be recognized at an angle of 70 Degree is recognized. The quality or the visibility of the reading is not affected.

The advantage is therefore that there is no need for costly, register-accurate production of the lenticular screen.

Surface reliefs that have already been applied would automatically focus a laser beam and a locally limited, increased energy density can be achieved in the desired depth of a laminate composite. In the known method, however, the laminate composite must be tilted and / or the laser beam angle must be changed in each case, which is not necessary according to the invention. In addition, the new method enables a significantly greater design freedom with regard to the optical lens parameters and, above all, a less expensive manufacturing process.

An important feature of the invention is that certain authenticity features are first introduced into a laser-capable structure by means of laser inscription, these authenticity features being generally referred to as elements.

In this case, these elements can be introduced by blackening in the area of a laserable film, a volume element or a multilayer laminate, or color structures can also be introduced. Color structures of this type are generated by laser irradiation and by a corresponding chemical conversion process, so that different color impressions arise in the corresponding irradiated volume element.

It is very important in this type of laser processing to use finely focused Nd-YAG laser light at preferably 1064 nm, that is to say in the infrared range, so that when using so-called laser-transparent or transparent films and also conventional IR-transparent ones Printing inks, the laser beam passes through such laminate layers without significant thermal stress and only causes blackening due to carbonization or carbonization in laminate films and / or printing inks with high IR absorption. However, the authenticity features can also be achieved by a photochemical reaction with a suitably selected laser wavelength (s) and corresponding, suitable pigments or fillers or printing ink combinations in the form of color effects. The invention is therefore not limited to the introduction of only black and white colored elements, but any colored elements can also be introduced into a volume element of a data carrier.

The desired tilting effect is now achieved in that the corresponding microstructures, with which it is possible to view the introduced elements differently from two different angles, are applied subsequently only after the introduction of such elements by means of a laser beam into a volume element of a data carrier.

It is a significant advance over the prior art, because the prior art required that the optical microstructure be attached first using expensive embossing processes, and that the security elements in the volume element of the data carrier be introduced through this optical microstructure. This is now dispensed with according to the invention and instead elements are first introduced into the unprepared data carrier (which therefore does not yet have the microstructures necessary for optical differentiation), and only then are the microstructures necessary for optical differentiation (production of the tilted image) applied to the card.

Within the scope of the present invention, all optically effective microstructures are claimed that can consist of different elements:

1. any form of cylindrical or other converging lenses

2 especially Fresnel lenses

3 microstructures in the form of applied hologram layers, which must be at least translucent, wherein such applied hologram-effective microstructures can work both with a diffraction effect and with a refraction effect

In the case of such holograms, preference is given in particular to those hologram structures in which a high first order diffraction efficiency is achieved.

In a further embodiment of the invention, it is preferred if the optically active lens system consists of Fresnel lenses. In this case, the strong material displacements for the production of cylindrical lenses according to the prior art are avoided by the division into lenses arranged in a stepped manner (Fresnel lenses), and this results in great design freedom.

The advantage is that when producing such a Fresnel lens embossing with the reduction of the embossing depth by a factor of 2 to 10, only very short cycle times are required compared to conventional lens systems. The Fresnel lenses can therefore be applied to an already finished single card without any significant material displacement and thus without optical distortion problems, and the card previously labeled with the laser can be further processed with the existing positioning system to produce the lens system.

The high initial costs for a number of stamping press plates can be dispensed with, and small orders can also be produced inexpensively with the new process, since only a single stamp is required, the service life of which is almost unlimited and which only has to be eliminated by mechanical operator errors.

It has turned out to be a particularly advantageous enhancement of the visual effect that a surface embossed with a Fresnel lens structure is additionally provided with a so-called high index coating in such a way that an approximately lambda / 4 effect is preferably achieved.

This achieves an optimal diffraction efficiency.

When using such Fresnel lenses, it is preferred if the tips of the lenses do not protrude beyond the card surface, since otherwise an undesirable material removal of these tips would result.

In the second method according to the invention and in the second production variant, so-called 2-channel holograms are used and in particular a) sinusoidal gratings are used, and b) toothed gratings This manufacturing process can also be used in combination with the embossed lens structures. Incidentally, all of the different optical readout methods described here (including also those to be described later) can be combined with one another, for example by diffraction gratings being superimposed on the embossments or assigned adjacent to them.

Diffraction effects on the grating structure are therefore used to read out the information below from different viewing directions. What is important here is the wavelength variants of the laser and the aperture-shaped intensity distribution of the laser beam, which leads to novel effects. The small thickness in the range from less than 2 to a maximum of 10 micrometers of such holographic elements has proven to be particularly advantageous.

The two-channel holograms mentioned are merely a preferred embodiment when it comes to introducing two different microstructures into the surface (hologram layer) of the card. Of course, the present invention is not limited to this, but multichannel holograms can also be attached, in which case more than two microstructures are attached and the entire optical elements which lie below in the volume element of the data carrier are then from more than one two viewing angles visible separately from each other.

The term “toothed grating with a sawtooth structure” is understood to mean so-called “blazed” grating.

These gratings are preferred because they have a higher diffraction efficiency than sinusoidal gratings.

In the third method according to the invention and in the third production variant, so-called volume holograms are used, which are typically 10 μm thick layers or foils. Different effects can be effective alone and in combination. Namely a diffraction without refraction or a combination of both physical effects, i.e. diffraction and refraction.

Usual kinegram or hologram foils (eg TKO foil) can realize a maximum of 0.5 my steps; with laminating TKO films, however, 2 to 3 my structures would very likely be realizable. In the fourth method according to the invention and in the fourth manufacturing variant, the three methods mentioned can now be produced in such a combined manner that initially conventional laminate cards with high-gloss surfaces are produced and these are preferably provided with the information necessary for a wobble security image in a laser engraving process and the corresponding optical microstructures are subsequently applied, which are optionally embossed as a Fresnel lens structure and / or are embossed as corresponding additive optical microstructures. Attention should be paid to a translucent design of all these optical elements.

It is therefore lasered into a data carrier or generally a security or value product into the unprepared surface (without any surface lenticular design), whereby an inclination of the laser or the card is no longer necessary. Therefore, the laser processing process according to the invention is faster because tilting the card and / or the laser extends the process.

Another advantage is that there is no need to have exactly focusing lenses which automatically focus the laser beam at a depth of about 100 to 300 micrometers in order to be able to write the authenticity elements at all in a defined, constant depth. The lens and / or diffraction system subsequently applied only has to permit an approximate reading of the information from different (not necessarily complementarily identical) viewing directions. However, it is preferred if, during the subsequent application of the optical element, to a relatively precise registration, i.e. Positioning of a few 5 micrometers is taken into account.

However, this is easily feasible in terms of production technology when using one and the same 3-point registration system in the laser processing process and when applying the optical element.

Typical application examples according to the invention are described in more detail in the following points:

1. Laser Typical: Nd: YAG laser with 1,064 nm and a focus of typically 50 micrometers (preferred range between 25 to 300 micrometers).

1.1 Frequency-doubled Nd: YAG Laser SHG ... Second harmony → 25 my focus

1.2 Frequency tripled Nd: YAG Laser THG ... Third Harmony → 12 my focus In other words, with such new / novel laser systems, laser focus areas in the visible and UV range can be used for extremely small lettering / marking effects and can be realized even more efficiently.

2. Color: generation of color effects by laser, i.a. photochemical effects are used, since thermal effects in a thermoplastic laminate structure are not particularly suitable. The color effect can, on the one hand, enable very special wiggle effects through such new systems based on appropriately selected layers (pigments, etc.). However, a color effect can also be obtained holographically.

3. Aperture: a new generation of lasers will have apertures and very different geometric laser points can be generated with it.

4. Laser pulse length: with the new laser systems extremely short pulses can be generated, or with the number of pulses / length the blackening / multiple labeling can be realized.

The advantage of laser processing is that the tilting or wobble effect cannot be verified (resolved) in one operation without using an optical system.

Not only can cylindrical and / or tilting effects be generated from two sides, but image sequences are also possible and isotropic arrangements can also be implemented.

There is also the advantage of a full-surface design of the card, because even larger areas can be used when applying a subsequent (patch) optical element.

The present invention is based on the knowledge that not only the known lens raster in the form of cylindrical lenses allow interesting and difficult to falsify effects for the realization of a wobble image, but also that spherically arranged Fresnel lenses or holographically arranged structures when using special laser Optics enable such effects and the type of arrangement of the lenses from a regular to a statistical distribution is possible. Modulated and, in particular, frequency-modulated distributions of the lenses can also be selected. The corresponding embossing stamps or embossing plates or holographic layers must be adjusted or matched to the laminate layer structure and here in particular to the thicknesses of the individual layers with the corresponding refractive indices or to the refraction and diffraction properties.

A further exemplary embodiment of the invention relates to the fact that a holographic microstructure can be introduced into a volume of the multi-layer data carrier by means of different insertion methods.

In a first insertion process, a transmission surface hologram is laminated as a film body in the multilayer card structure, where it forms a specific volume element of this data carrier.

In another embodiment, a volume hologram can be introduced, which is also introduced into a film and this is laminated in the card assembly.

Such volume holograms are typically photopolymer layers.

It is important here that the hologram is first introduced into the data carrier in a specific layer or on the surface and only then are the authenticity features written into the card using a laser.

This lasering of authenticity features takes place exactly according to the state of the art, e.g. according to EP 0 216 947 B1 or EP 0 219 012 B1.

An important difference in the present invention, however, is that it is a microstructure integrated into the card structure and that no optically effective lens system is required on the surface of the card structure.

The subject matter of the present invention results not only from the subject matter of the individual patent claims, but also from the combination of the individual patent claims with one another.

All information and features disclosed in the documents, including the summary, in particular the spatial depicted in the drawings Training are claimed as essential to the invention, insofar as they are new compared to the prior art, individually or in combination.

In the following, the invention will be explained in more detail with reference to drawings showing several possible embodiments. Here, from the drawings and their description, further features and advantages of the invention that are essential to the invention emerge.

Show it:

FIG. 1 shows schematically a layer structure of a data carrier in a preferred embodiment,

FIG. 2: schematically shows the section through the upper part of the data carrier according to FIG. 1 in a first method step,

FIG. 3: section through the data carrier in a second method step,

FIG. 4: a data carrier modified with respect to FIG. 3 with additional layers,

FIG. 5: the explanation of the function of the data carrier,

FIG. 6: an embodiment modified compared to FIG. 4,

FIG. 7: an embodiment modified compared to FIG. 6,

Figure 8: Top view of the data carrier of Figure 7 in the direction of

Arrow VIII,

FIG. 9: a surface structure of the

Disk,

FIG. 10: schematically drawn, enlarged section through a lens structure according to the invention,

FIG. 11: a further enlargement of the lens structure according to FIG. 10, FIG. 12: the representation of a further embodiment and a further production method, in which a holographic microstructure is first introduced into the layer structure of the data carrier,

Figure 13: the exposure of the data carrier according to Figure 12 in section. FIG. 14: the finished data carrier according to FIG. 13

In general, the data carrier is provided with the reference symbol 1, the data carrier being any security element, security document, card or the like. Reference is made to the general description in EP 0 216 947 B1 and EP 0 219 012 B1, the disclosure content of which is used in full for the disclosure of the present invention.

The data carrier 1 preferably consists of a first, non-laserable cover film forming the surface (more generally referred to as layer 2 because this does not necessarily have to form the top layer of the card), which is preferably transparent or translucent or opaque. A transparent, laserable layer 3 is arranged under this non-laserable cover film (layer 2).

Of course, the structure of this data carrier in the manner shown is not to be understood as limiting. The non-laserable layer 2 can also be omitted and instead the surface can be formed directly by the transparent laserable layer 3.

Likewise, it is not shown in the exemplary embodiment that the uppermost layer 2 or 3 can be covered by further protective layers, protective lacquers and the like.

It is also shown in FIG. 1 that an opaque layer 4 made of a carrier material is located below the transparent, laserable layer 3.

This layer can also have a translucent property instead of the opaque property.

Of course, this layer can also be omitted, since it is a pure carrier layer. It is only shown by way of example that the data carrier according to FIG. 1 is constructed mirror-symmetrically to its longitudinal center axis, ie the previously described layer structure from layers 2, 3, 4 is repeated in the lower part with layers 2 ', 3', 4 '. However, this is not a necessary solution. Any other layer structures can be used or the layers 2 ', 3', 4 'can also be completely omitted.

In a first method step, the data carrier according to FIG. 2, of which only the upper half is shown, is irradiated by means of a laser beam 28, 29.

The laser beam 28, 29 is in this case preferably focused on the layer transition or on the surface of the layer 3, so that corresponding optically visible elements 8, 9 are formed, which e.g. can result from blackening of layer 3. A color change can of course also be provided in layer 3 or on the surface of layer 4.

Layer 30 may also be formed as a printing layer, i.e. it can be provided with a printed image in any way, and additionally optically visible elements 8, 9 (authenticity elements) can then be introduced into these printed elements by means of the laser beams 28, 29.

As already stated, the respective laser beam 28, 29 is focused on the surface of the layer 30. However, the invention is not restricted to this. The laser beam 28, 29 can be effective in the entire volume element of the layer 3, so that the elements 8, 9 still protrude far into the layer 3 and form corresponding elements there.

It is now important that after the authenticity features have been introduced by means of a laser (laser beams 28, 29), an optically effective layer is only subsequently applied to the card structure. In the exemplary embodiment according to FIG. 3, a microstructure layer 5 is applied which either has holographically active elements, namely microstructures 6, 7, or which also consists of corresponding lens structures 14, as will be explained later with reference to FIGS. 10, 11 or also from a combination of both systems 5, 14.

It is therefore important that in the process step according to FIG. 2 the laserable elements 8, 9 are first introduced as authenticity elements and only then the optical ones Structure (microstructure layer 5) is applied to achieve the desired tilt effect.

In the exemplary embodiment according to FIG. 3, the tilting effect is achieved in that different microstructures 6, 7 are applied in the microstructure layer 5, one element 8 preferably being located centrally below the microstructure layer 6, while the other element 9 is located centrally below the microstructure 7.

Reference is made here to FIG. 5, where it is then explained how the different elements 8, 9 become visible from different viewing directions.

In comparison to FIG. 3, FIG. 4 also shows that the microstructure layer 5 is introduced as the embossing layer 10 into the uppermost, non-laserable layer 2, the embossing layer 10 preferably not projecting beyond the surface of the layer 2.

This structure can also be covered by a highly refractive protective layer 13, whereby the diffraction effect of the underlying, embossed microstructure layer 5 'is further improved.

In Figure 5 further details of the function of the invention in this embodiment of Figures 2 to 4 are now explained in more detail.

If you now look at the surface of the data carrier from a viewing direction 25 with a viewing beam 20, then this viewing beam is bent, for example at an angle 22 of 60 ° in the first microstructure 6, and the element 8 underneath is thus visible in the viewing beam 20 under the viewing direction 25 ,

The same applies analogously to the viewing direction 26 and the viewing beam 21, which falls obliquely on the surface of the data carrier at a complementary angle of 60 degrees and is thereby bent on the microstructure 7, so that the element 9 lying next to it is thereby visible. Instead of the term “diffraction”, the more general term “deflection” will be used in the following, because such microstructure layers have both diffraction and refraction properties. If you look at element 9 from the direction of view 25, then element 9 should not be visible.

The route 23 (A ') means that the deflection with respect to the route 23 or 24 should take place in such a way that the neighboring element is not seen as far as possible in the viewing direction. That is, the element 9 should not be visible from the viewing direction 25.

If one imagines to explain the lines 23, 24 that the element 9 is a point light source that emits in all directions, then it should be ensured that the beam of the line 23 does not spread while the beam of the line 24 is spreading and is visible. The routes 23, 24 are complementary to one another.

The beam of the path A 'should therefore not penetrate through the microstructure 6. The rays a 'and a "thus behave complementarily to one another.

FIG. 6 shows, as a modification of the previously described exemplary embodiment, that the microstructure layer 5 can also be introduced in the region of a highly refractive lacquer layer 11, which is covered at the top by a low-refractive protective layer 12.

FIG. 7 shows the reversal of the exemplary embodiment according to FIG. 6, where it is shown that the microstructure layer 5 is introduced in a low-refractive layer 12 which is covered at the top by a highly refractive protective layer 13.

FIG. 8 shows, as an exemplary embodiment, the structure of the microstructure layer in plan view, where it can be seen that the different microstructures 6, 7 form, for example, parallel bar-shaped grids.

In another exemplary embodiment according to the invention it is provided that three microstructure elements form the microstructure layer of a data carrier, in addition to the microstructures 6, 7 there is also another microstructure 27 and the microstructures 6, 7, 27 all have different refractive / diffractive properties ,

These structures are preferably arranged hexagonally and complement one another, so that they extend approximately in a tiled shape over the surface. However, the invention is not restricted to this; the microstructures can form the surface in any manner, for example point-shaped, grid-shaped, line-shaped, wavy, elliptical and the like.

In addition to the three microstructures 6, 7, 27 described, any other microstructures with other diffractive, refractive effects can also be provided.

This only increases the number of viewing directions from which the underlying elements 8, 9 become visible in the data carrier.

The exemplary embodiment in FIGS. 10, 11 describes that the microstructure layer 5 is now designed as a lens layer with individual Fresnel lenses arranged next to one another.

As already stated in the general description section, the arrangement of Fresnel lenses has the advantage that only a small embossing depth is required with such stepped lenses, which is a factor of 2 or 3 less than the embossing depth of conventional cylindrical lenses.

A Fresnel lens is a lens with a large aperture ratio and collecting effect, the part of the Fresnel lens in the middle is formed by a spherical or aspherical thin lens. Ring-shaped zones are attached around this central part. The whole arrangement is dimensioned so that the center piece and the individual zones have the same focus and almost the same thickness. The radii of curvature belonging to the individual zones become larger with increasing zone height, so that the different centers of curvature are not on the optical axis.

The structure of the Fesnel lenses according to FIGS. 10 and 11 means that each Fresnel lens is symmetrical about the central axis 19. The lens diameter is generally shown at 18.

It is now important that the embossing depth 17 or structure depth for a lens diameter 18 of, for example, 300 micrometers is only, for example, 17 micrometers. The grid here is approximately 270 micrometers, ie the lens structures 14 according to FIG. 10 overlap slightly in each case in the edge region. The upper edge 15 of the lens structure 14 should, if possible, be below or flush with the surface of the data carrier 1 in order to protect the lens structure 14 from mechanical damage from the top.

The lower layer 16 thus defines the embossing depth or structure depth 17, down to which the microstructure layer 5 is introduced into the data carrier 1.

It is now important that the element 8 is visible with the viewing beam 21 only because of the refractive properties of this lens structure 14, while the element 9 lying next to it is visible with the viewing beam 20 and the viewing direction 25.

It is important in this exemplary embodiment according to FIGS. 10 to 12 that the lens structure 14 is only applied after the introduction of the authenticity elements 8, 9 by means of corresponding laser beams 28, 29, e.g. by embossing.

However, other manufacturing methods for manufacturing the lens structure 14 can be used, such as e.g. Surface application of hologram and kinegram foils which form such microstructure layers in order to form the lens structure 14.

However, the invention is not restricted to the application of hologram and kinegram foils; any microstructures can generally be applied subsequently.

In a different form of alternative, for which separate protection is claimed and which is independent of the previously described exemplary embodiment, a different manufacturing method is claimed.

According to FIG. 13, it is shown that the layers 2, 3, 4 are again present in a data carrier, the microstructure layer 5 now being introduced into the layer 3 in this exemplary embodiment. This microstructure layer 5 is introduced by lamination of this layer in the layer structure. This means that the microstructure layer 5 is introduced as a separate film element between the layers, for example by lamination. Such microstructure layers can of course also be introduced into layer 3 in a different way.

After the introduction of the microstructure layer 5, which forms the microstructures 6, 7, the elements 8, 9 are now introduced by appropriate lasering with the laser beams 28, 29, these laser beams 28, 29 being known per se at an angle to the surface of the data carrier 1 are applied in order to penetrate the microstructures 6, 7 in a specified manner.

This is a modified method compared to the main method, because according to this variant the microstructure and then the authenticity elements 8, 9 are introduced first. Protection is also sought for this variant because the penetration of the already existing microstructure for the purpose of writing in the authenticity elements 8, 9 does not necessarily depend on the focusing ability of this microstructure, as is a requirement in the prior art. If only a diffractive microstructure is used, then it is irrelevant for writing elements 8, 9 into the volume of the card whether the microstructure already exists or not.

However, the following description applies to both variants, namely to the first variant in which the elements 8, 9 are written without the microstructure 5, 6, 7, 14, 27 present and also to the second variant in which the elements are written 8, 9 happens with existing microstructure 5, 6, 7, 14, 27.

Depending on the angle of the laser beam 28, 29, either the element 8 or the element 9 is accordingly burned into the laserable layer 3 and applied.

Here again it applies that instead of baking, a corresponding color change can also be carried out in this layer.

It is important in this exemplary embodiment that the authenticity elements are introduced through the microstructure layer integrated in the card structure by means of laser beam 28, 29, but that any optically effective lens systems can be dispensed with because the microstructure layer 5 is present in the card structure itself. FIG. 14 shows the finished data carrier, where it can be seen that the microstructures 6, 7 overlap and overlap one another in order to bring about the angle-specific introduction of the laser beams 28, 29 for the production of corresponding elements 8, 9.

An advantage of the invention is that a superimposed registration of the microstructure film 5 and the elements 8, 9 located underneath it in the layer 3 is not absolutely necessary.

If there is a Passer offset, then it can at most happen that one element 8 is visible, for example, from a viewing angle of 20 °, while the other element 9 is only visible from a viewing angle of 60 °.

However, the register offset does not play an important role in the recognizability of the different elements 8, 9.

Zeichnunqs-Leqende

disk

Layer (non-laserf.)

Layer (transp. Laserf.)

Layer (opaque)

Microstructure layer 5 '

Microstructure 1

Microstructure 2

Element 1

Element 2

embossing layer

Lacquer layer (high refractive index)

Protective layer (low refractive lacquer)

Protective layer (high refraction)

lens structure

top edge

layer

structure depth

Lens diameter

mid-axis

view bundle

angle

Route a '

Route a "

line of sight

microstructure

laser beam

layer

Claims

claims

1. A method for producing a data carrier with at least one transparent cover film (2) and an underlying card body (3, 4), in which authenticity elements (8, 9) pass through the cover film (2) using a laser beam (28, 29). be written into the card body, which have different information content from different angles on the data carrier (flip or wobble image), characterized in that in a first process step the authenticity elements (8, 9) are first inserted into the card body (3, 4) through the cover film (2) are written through and that in a second process step the microstructure (5, 6, 7, 14, 27) required for reading from different viewing directions is attached to or in the cover film (2).

2. The method according to claim 1, characterized in that the on or in the cover film (2) attached microstructure (5, 6, 7, 14, 27) on the surface additionally by at least one further layer (11, 12, 13) is covered.

3. The method according to claim 1 or 2, characterized in that the elements (8, 9) by blackening in the region of a laserable layer (3), one

Volume element or a multilayer laminate can be introduced.

4. The method according to one or more of claims 1 to 3, characterized in that the elements (8, 9) are generated in the form of color structures by laser radiation and / or by a corresponding chemical conversion process.

5. The method according to one or more of claims 1 to 4, characterized in that an Nd-YAG laser is used with a wavelength of 1064 nm, which generates a localized carbonization (carbonization) in the laserable layer (3).

6. The method according to one or more of claims 1 to 5, characterized in that the authenticity features (elements 8, 9) by a photochemical reaction in the layer (3) with a suitably selected laser wavelength and corresponding, suitable pigments or fillers or Ink combinations in the form of color effects are generated.

7. The method according to one or more of claims 1 to 6, characterized in that the optically active microstructure is produced by embossing the cover film (2).

8. The method according to claim 7, characterized in that a Fresnel lens arrangement (14) is produced by embossing.

9. The method according to claim 7 or 8, characterized in that the embossing is carried out with a single stamp.

10. The method according to one or more of claims 7 to 9, characterized in that the Fresnel lens structure (14) is covered with a highly refractive coating upwards in order to achieve an enhancement of the visual effect by a lambda / 4 effect.

11. The method according to one or more of claims 1 to 10, characterized in that a sinusoidal grating which diffracts the optical rays is used as the microstructure (5).

12. The method according to one or more of claims 1 to 10, characterized in that a toothed grating which diffracts the optical rays is used as the microstructure (5).

13. The method according to one or more of claims 1 to 12, characterized in that a two- or multi-channel hologram layer is used as the microstructure.

14. The method according to one or more of claims 1-14, characterized in that a volume hologram is used as the microstructure layer.

15. Card-shaped data carrier with authenticity elements (8, 9) in the interior, consisting of at least one cover film (2) and an optical readout system arranged on the top, through which the authenticity elements (8, 9) arranged in the interior are viewed from at least two different viewing directions can be read out with different information content, characterized in that the optical readout system consists of a lens structure (14) made of Fresnel lenses.

16. Data carrier according to claim 15, that the lens structure (14) of the Fresnel lenses is embossed (embossing layer 10).

17. A data carrier according to claim 16 that the embossing layer (10) is covered by an optically high-index protective layer (13).

18. Data carrier according to one or more of claims 15 to 17, characterized in that the microstructure layer (5) is introduced in the region of a highly refractive lacquer layer (11) and is covered at the top by a low-refractive protective layer (12).

19. Data carrier according to one or more of claims 15 to 17, characterized in that the microstructure layer (5) is introduced in the region of a low-calculus lacquer layer (12) and is covered by a highly refractive protective layer (11).

20. Card-shaped data carrier with authenticity elements (8, 9) in the interior, consisting of at least one cover film (2) and an optical readout system arranged on the top, through which the authenticity elements (8, 9) arranged in the interior are viewed from at least two different viewing directions can be read out with different information content, characterized in that the optical readout system consists of a microstructure (6, 7) with holographically active elements.

21. Data carrier according to one or more of claims 15 to 20, characterized in that the microstructure consists of a combination of embossed lens structures (14) and one or more diffractive and / or refractive microstructures.

22. Data carrier according to one of claims 20 or 21, characterized in that the microstructures 6, 7, 27 have a regular structure and are preferably arranged in a bar-shaped or tiled (hexagonal) manner next to one another on the data carrier above the elements (8, 9).