EP2828093B1 - Security document having a perforation window, and method for the production thereof - Google Patents

Description

The invention relates to a security document and to a method for its production, in particular a security document having at least one security feature, which is optically verifiable and has different optical effects depending on the viewing side of the security document.

A variety of security documents are known in the art. As such, all those objects are referred to which comprise at least one security feature which makes falsification, imitation, unauthorized duplication or the like difficult or preferably impossible.

Security documents include, for example, ID documents, passports, identity cards, identification cards, driving licenses, vehicle registration documents, vehicle registration documents, access cards, company identity cards, access cards, bank cards, credit cards, visas, but also counterfeit-proofed labels, entrance tickets, banknotes, postage stamps, securities or the like. Such security documents embodying a value, such as postage stamps, securities or banknotes, are also referred to as value documents. A distinction between value and security documents is not always clearly possible and in view of the subject invention also not essential. In the sense of the objects described here, value documents are always understood as security documents.

From the prior art, different security features are known, which are optically verifiable. As optically verifiable security features, all such features are considered that can be verified by detecting light transmitted through the security feature or reflected or remitted thereto. As light here is understood all electromagnetic radiation, which may be in the visible, infrared or ultraviolet wavelength range.

For example, a group of security features exhibiting a different effect depending on the viewing side includes volume holograms, in particular reflection volume holograms, which underlie from the one viewing side when illuminated with white light under a predetermined direction of illumination make detectable at least one direction a detectable stored in the hologram image. When viewed in phantom, a different optical effect can be observed, since here the light reflected at the hologram during the reconstruction of the reflection volume hologram is "missing".

From the WO 2005/058610 A2 a data carrier according to the preamble of claim 1 is known in which are introduced by a laser beam markings in the form of patterns, letters, numbers and / or images due to caused by the laser beam, resulting from material changes local changes in the optical properties of the data carrier are visible. The data carrier comprises a transparent in the visible spectral range, laser-sensitive recording layer, which is provided with a surface relief in the form of a lenticular grid. The markings are introduced into the recording layer with the laser beam from different directions through the lenticular grid and can be recognized from the same directions when viewed later. The data carrier is transparent at least in the area of the introduced markings.

From the WO2009 / 062229 A1 For example, a security document is known that includes an arch having a front surface of a back surface and side edges. The arch comprises one or more windows or half windows made of transparent or translucent material. In this case, a half-window is not completely transparent, so that although light penetrates through the half-window, without, however, an object located behind the half-window being clearly perceptible by the half-window. At least one of the windows or half-windows extends to one of the side edges, the window or the half-window comprising a feature, for example an indication of value or a self-contained security feature.

A further group of security features is embodied in security documents in that a multiplicity of lens elements are formed at a distance from visually perceptible information stored in the security document. An example of this is the so-called CLI (Changeable Laser Image) and MLI (Multiple Laser Image) features, which have a viewing angle dependence when viewed from a side where the lenses are located between the viewer and the stored information. When viewed from the other side where the information stored in the document is before the Lens elements are arranged, this angle-dependent effect is not perceived by the viewer, since the lenses in this case do not modify a light propagation from the information stored in the document to the viewer.

From the DE 199 34 434 A1 is a value and security document with perforations known in which micro-channels are arranged as additional security and authenticity. Embodiments are described in which microchannels are introduced at different angles with respect to a surface normal of the layers from which the security document is formed.

From the WO 03/022598 A1 For example, a record carrier is known which has an upper layer which has on its outer side a plurality of lenticular lenses and on the back a display element which appears to be movable about at least one axis when the record carrier is tilted. The lenticular lenses extend only over a portion of the entire outside. The presentation element is a security element printed on an inner card layer. It is not stated how the lenticular lenses are inserted into the document body.

From the DE 10 2008 008 044 A1 a cost-effective method for producing security and / or value documents is known, which are suitable for producing flexible and tamper-proof structures with low thermal stress, wherein the Surface structure in the top and / or bottom of substrates used for the production of documents with an embossing device having at least one embossing tool, each having a contact surface is embossed using an embossing pressure and using ultrasound, wherein the contact surface is the same size as or is greater than the top or bottom of the substrate. Embodiments of the manufacturing method are described which impress microlenses in a document body.

From the DE 10 2008 031 653 A1 discloses a method and apparatus for introducing a security feature into a security or security document, the security or security document comprising a document body having at least one thermoplastic surface layer, the method comprising the steps of: providing the document body; Providing and / or creating a structured sonotrode that is or will be coupled to a sound source; Arranging the document body relative to the sonotrode; Contacting the sonotrode and the surface layer of the document body and simultaneous coupling of sound waves via the sonotrode into the value or security document, so that a relief structure is formed in the surface layer, wherein the sonotrode is provided and / or manufactured with a structuring which is a target intrusion plane and the sonotrode is patterned such that protruding portions project from the target intrusion plane and recessed portions project into the target intrusion plane, the sonotrode being moved into the document body during sonic engagement by applying pressure until the target intrusion plane coincides with a document body surface target level and the protruding portions recessed relief structures and the recessed areas create protruding relief structures in the surface layer.

From the EP 0 216 947 A1 a card-shaped data carrier with a substrate and at least one transparent cover film is known. The substrate is provided with information detectable by the cover sheet using a laser beam, the transparent cover sheet carrying a relief applied at least partially overlapping the information area prior to recording the information, which characteristic changes the information recording by virtue of its optical lens action. Depending on the irradiation direction of the laser light, the information is stored at different locations in the substrate. Likewise at a Visual inspection perceived different information as a function of a viewing angle.

From the EP 0 219 012 B1 a data carrier is known in which information is introduced by means of a laser beam in an inner volume region, which are visible in the form of changes in the optical properties due to an irreversible, caused by the laser beam material change. For example, card-shaped data carriers which have a lenticular grid on a surface are described. The lenticular grid can be embossed during a laminating process by incorporating a negative of the lenticular grid into a corresponding laminating plate. Likewise, a thermostable embossing die can be used, which is inserted between the transparent cover layer and the lamination plate. It is further described that the card can be produced by means of a lamination process and the lenticular screen is subsequently introduced by means of an embossing punch or embossing roller. The information is introduced via a laser beam, which introduces information through the lens grid into the card body under different directions. This makes it easy to implement tilt pictures.

In the known from the prior art method and resulting security documents in which first an optical structure, preferably an optical structure in the form of a lenticular grid, is introduced into a surface and then the information is introduced by means of a laser beam on causing irreversible material changes, In essence, only information in the form of gray values can be stored. In addition, a subsequent addition of information can be used by re-laser irradiation to falsify the security document. Full color or colorful information storage is usually not possible. In the from the WO 03/022598 A1 Although the information can be printed in color, in particular colorful, but an achievable resolution for a viewing angle-dependent security feature is limited by the fact that shrinking processes occurring during insertion and integration of the printing information in the document body in the lamination process and an exact alignment of the printing information within the document body and in particular relative to the same time introduced in a lamination process microlenses is insufficiently guaranteed.

The person skilled in the art is aware of other different security features which show an optical effect which depends on the viewing side. In particular, diffractive and refractive structures formed on a surface or inside the security document can cause such effects.

Since the issuers of security documents have the interest to create ever new, as difficult to forge security features and to integrate in security documents, there is a need to create new, cost-effective, in particular mass-produced security features and thus novel security documents, methods for their production and to create new verification procedures.

The invention is based on the idea of specifying a security document, a method for its production and a verification method in which a security feature which, depending on the viewing side of the security document, produces different optical effects can be used in a security document which at the same time comprises at least one opaque layer having. In many security documents, it is desirable that a document body, which is often assembled from different layers of plastic, comprise at least one opaque layer, for example, to prevent transparency in at least some areas of the document. Although it is basically possible to combine a document made of a plurality of transparent material layers, for example in a lamination process, and to print one of the otherwise transparent substrate layers over a large area, in order to create an opaque background for other information and / or security features arranged in other layers. However, it has been found that large area printed substrate layers are often vulnerable to delamination, i. a separation of the document body at an originally existing layer edge represents. Therefore, it is desirable to provide the opaque layer by integrating a self-supporting, volume-opaque layer.

In order to be able to use viewing-page-dependent, optically verifiable security features in such security documents and to be able to use them with regard to the different effects observable when viewed from different sides, it is proposed to use a perforation of a plurality of To provide openings through the opaque layer, so that a view through the opaque layer is possible. It has been found that, despite the introduction of a plurality of perforations, even in a region which is extended over a wide area, a tendency to delaminate a document body assembled via lamination is virtually unaffected.

In particular, there is thus proposed a security document which comprises: a document body having a front side and an opposing rear side, the document body being manufactured using at least one flat, self-supporting opaque layer integrated in the document body between the front side and the back side, and wherein in the document body at least one optically verifiable security feature is formed, which has different optical effects with respect to viewing via the front and a view on the back, wherein in the opaque layer, a plurality of apertures formed and arranged so that an optical detection the at least one optically verifiable security feature is possible both when viewed through the front and when viewed through the back, wherein one of the two considerations a Durchsichtb Considering the openings in the opaque layer, and the other is a direct view, which does not occur through the openings, and the at least one optically verifiable security feature is formed, that in the direct observation and in the reviewing different optical effects are detected whose difference is not due to the presence of the opaque layer and / or the perforations.

Such a security document having a document body having a front side and an opposite back side can be verified by a method comprising the steps of detecting an optical effect of at least one security feature when the security feature is viewed through the front side, and detecting another optical effect when viewing the same by the back side at least one security feature, wherein one of the two considerations is performed as a see-through observation, wherein the viewing of the at least one security feature by a plurality of openings in a flat, self-supporting opaque layer, the the document body is integrated, and the other of the two considerations is performed as a direct observation in which the viewing is not performed by the plurality of apertures of the opaque layer, and comparing the detected optical effect and the further detected optical effect and deriving verification information.

For the production of such a security document, a method is provided comprising the steps of: inserting a plurality of apertures into an opaque self-supporting layer; Integrating the opaque layer having the plurality of apertures into a document body having a front side and an opposite rear side; Forming at least one optically verifiable security feature in the document body in such a way, wherein the at least one optically verifiable security feature is formed and arranged with respect to the plurality of openings, that an optical detection of the at least one optically verifiable security feature both in a view through the front and is possible when viewed through the back, wherein one of the two considerations is a review, which is done through the openings in the opaque layer and the other is a direct view, which does not occur through the openings, and the at least one optically verifiable security feature is formed in that it has different optical effects with respect to front-side viewing and rear-side viewing of the document body, and thus in the direct viewing and in the see-through tion different optical effects can be detected, the difference is not caused by the presence of the opaque layer and / or the perforations.

A novel security document and a novel method for the production of a security document are provided, which permits reliable verification, as a rule, without the aid of further aids.

definitions

As a self-supporting layer is called, which can be handled without support by other substrate layers.

A layer which opposes a transmission of light in a certain wavelength range almost completely is called opaque. It will be understood by those skilled in the art that the term opaque refers to each wavelength range of light that is relevant to verification of a corresponding optically verifiable security document. For example, if an optically verifiable security feature can only be verified by the use of ultraviolet light, then the opaque layer is, of course, opaque in the ultraviolet wavelength range. If light from different wavelength ranges is used for the verification, then the opaque layer is to be regarded as opaque at least in the wavelength range whose light is detected during the verification.

As a document body, an entity is understood, which is composed of different individual components into a whole. Preferably, the plastic-based document body is assembled from a plurality of plastic layers. Suitable plastic materials are, in particular, those which are based on a polymer material from a group comprising PC (polycarbonate, in particular biphinol A polycarbonate), PET (polyethylene terephthalate), PMMA (polymethyl methacrylate), TPU (thermoplastic polyurethane elastomers) PE (polyethylene) , PP (polypropylene), PI (polyimide or polytransisopropene), ABS (acrylonitrile-butadiene-styrene), PVC (polyvinyl chloride) and copolymers of such polymers. However, the document body may also comprise other materials, such as pulp based, such as paper or the like. Further, a document body can be integrated with other elements such as metal foils, metal strips, exposed hologram films, but also microelectronic devices such as microchips, devices, or the like.

Document bodies are particularly preferably designed as card-shaped documents whose areal extent at a front side and an opposite back side is substantially greater than a distance between the front and the back side.

As a breakthrough of a layer, a through-hole is denoted by the layer. However, the opening need not be filled with a material whose material properties differ at least from the material through which an opening is formed. As perforations in particular microholes are considered, which are formed as perforations.

Preferred embodiments

Preferably, the plurality of openings is formed only in a localized area of the opaque layer.

Particularly advantageously, the openings can be introduced by means of a laser perforation in the opaque layer. For this purpose, focused laser radiation is directed onto the opaque layer, which is usually generated pulsed. The laser radiation is able to locally introduce sufficient energy into the opaque layer that openings are formed in the film.

The perforations are preferably produced in the form of microholes having diameters in the range from 0.5 μm to 200 μm, particularly preferably in the range from 10 μm to 20 μm. A shape of a cross-sectional area of the openings can be varied within wide limits. Preference is given to circular or elliptical cross-sectional areas, since they can be generated without much effort by means of laser radiation of lasers which are freely available in the state of the art, without the need for further optical elements forming a beam profile.

In a preferred embodiment, the apertures are arranged in a grid in order to achieve the highest possible transparency in the region of the majority of the introduced apertures of the opaque layer.

In a particularly preferred embodiment, a grid is used, which is created from hexagonal cells. At each grid point an opening is formed. In this way, transparencies of up to about 60% transmission can be created without a tendency to delamination in the area of the majority of the openings can be seen.

In one embodiment, the apertures introduced into the opaque layer are filled with a transparent or translucent material before or during a lamination process. Preferably, backfilling takes place with a plastic material made from the same base stock as the opaque layer, but having a different opacity. If a document body, for example, made of several layers of film, which on Base are made of polycarbonate, of which the opaque layer is colored in volume, the introduced openings are filled, for example, with a transparent polycarbonate-containing material. This can be scribed, for example, in liquid form.

It is also possible to use a polycarbonate-based ink by means of a printing process, which is "sucked" into the openings due to capillary forces, provided that the ink is printed in a targeted manner over the perforations.

Other embodiments may provide that for filling a granule based on the same polymer is used, from which the opaque layer itself is formed.

If the opaque layer is made of a base material that deviates from the base material of the adjacent layers in the finished document body, it is advantageous to fill the openings with a material that is similar to the base material of the adjacent layers. As a result, reliable lamination compounds are formed through the apertures.

Overall, however, it is preferred to produce as many layers as possible, preferably all layers, of the document body on the basis of the same plastic material, since a monolithic document body can thus be produced in which no phase boundaries at the original layer boundaries of the films are recognizable after the lamination process with regard to the plastic structure where the document body is made. The layer boundaries can then be recognized only on the basis of insinuations, which, for example, determine the opaque property of the material layer.

The novel security feature results from the combination of a see-through window formed by the apertures in the opaque layer with a security feature that shows different, contingent effects. For example, diffractive structures can be used as security features because an observable effect is contingent-side dependent.

If, for example, a hologram is used as the security feature, then this can be inserted between the layers during the lamination process.

Volume holograms are particularly preferred since, because of the high color and angle selectivity, they are also illuminated with white light, i. Light of a continuous spectrum, can be reproduced. While the reflection hologram reconstructs the information in reflection from a viewing side under a particular viewing and illumination geometry, complementary information can be seen from the opposite viewing direction under suitable illumination and viewing directions. The transmitted light is deprived of the light of the particular wavelength which is reflected by the hologram.

Another very suitable security feature is designed as a so-called CLI or MLI feature. This comprises an array of lens elements and spaced therefrom optically visible marks in the document body. The array of lens elements is preferably imprinted into an outer surface of the document body. The embossing can be done for example via a preformed lamination during the lamination process.

Preferably, the lens array covers only a portion of the surface so as not to hinder the perception of other security features that may be integrated into the document body. With respect to a direction which is predetermined by a surface normal of the front side or the rear side of the Dökumentkörpers, the lens array is thus formed above or below the plurality of openings.

A particularly preferred method for forming the lens array is an embossing method, in particular an ultrasonic embossing method, in which a sonotrode is brought into contact with the surface of a film or the document body blank prefabricated as a composite body, and the lens structure is impressed into the surface by ultrasound. During insertion, the sonotrode can be pressurized in addition to the application of ultrasound.

Other methods provide for structuring the lens structures by means of a laser ablation process.

The information stored in the document body can be introduced, for example, via a laser marking into an interior material or substrate layer of the document body. Preferably, for introducing the information, the already formed lens structures are used to direct laser light under different directions onto the lens structures and to mark information in a material layer underlying the lens structure. This layer of material may contain substances which promote absorption of laser light in this layer without appreciably restricting transparency. The marking via a carbonization then takes place, for example, only in such a layer. The other layers of the same plastic base material pass the marker light. Darkening then takes place in the focus points to which the individual lenses of the lens structure focus the incident light. Since the focus varies depending on the direction of irradiation relative to a main lens axis in the document, it is possible to store different information in the document body under different irradiation directions.

In a subsequent consideration of the stored information through the lens structures, the different stored information can thus be detected under different viewing directions depending on the viewing angle. If the opaque layer is below the stored information viewed from the upper side, in which the lens structures are formed, different information components are to be detected in a direct viewing of the information as described above, depending on the viewing angle. However, if one sees the security feature looking through from the opposite side of the document body, one obtains a static information of the introduced via the laser marking in the document information.

A preferred security document is thus characterized in that a viewing angle dependence of the review and the direct view is different. Such an embodiment is designed such that the at least one optically verifiable security feature comprises a plurality of lens elements to which a visually perceptible information is stored at a distance in the document. This storage can take place, for example, via a laser marking, in particular a carbonization of a part of the transparent plastic. However, the visually perceptible information can also be applied to an internal, otherwise transparent substrate layer to be printed and the lens elements are aligned aligned with the printed information in the document body.

In a further development, it is provided that the lens elements are not formed on the surface of the document body, but on the inside. For this purpose, the lens structure must first be introduced in a transparent film, for example by means of an ultrasonic embossing process. Subsequently, the resulting surface relief structure is filled by a transparent plastic material, which in the finished document body, for example, after a lamination process in which different layers are connected to each other to the document body, a different optical refractive index of the material from which the layer is formed, in the the lens structure is first impressed. In such an embodiment, the lens structure, the information stored in the document as well as the see through the plurality of openings in the opaque layer see-through windows are arranged to each other that, for example, a review of the security feature viewing angle dependent and direct viewing of the security feature provides static information. However, embodiments are also feasible in which the direct consideration shows an angle dependence and the reviewing shows a static information.

Fig. 1:

eine schematische Darstellung eines Sicherheitsdokuments mit einem CLI-Sicherheitsmerkmal sowie einem über eine Vielzahl von Durchbrechungen in einer opaken Schicht gebildeten Durchsichtfenster;

Fig. 2a-2e:

unterschiedliche Ansichten des Sicherheitsdokuments nach Fig. 1;

Fig. 3:

eine schematische Darstellung eines Sicherheitsdokuments, welches ein Reflexionsvolumenhologramm als Sicherheitsmerkmal und ein über Durchbrechungen in einer opaken Schicht gebildetes Durchsichtfenster umfasst;

Fig. 4-6:

unterschiedliche Ausführungsformen von Sicherheitsdokumenten mit einem CLI/MLI-Sicherheitsmerkmal und einem über Durchbrechungen in einer opaken Schicht gebildeten Durchsichtfenster;

Fig. 7:

eine schematische Darstellung eines Sicherheitsdokuments mit einer innenliegenden Linsenstruktur für ein CLI-Sicherheitsmerkmal und einem durch eine Mehrzahl von Durchbrechungen in einer opaken Schicht gebildeten Durchsichtfenster;

Fig. 8:

eine schematische Darstellung eines Herstellungsprozesses eines Sicherheitsdokuments; und

Fig. 9:

ein schematisches Ablaufdiagramm einer Ausführungsform eines Verifikationsverfahrens.

The invention will be explained in more detail with reference to a drawing. Hereby show:

Fig. 1:

a schematic representation of a security document with a CLI security feature and a through a plurality of openings formed in an opaque layer through-window;

2a-2e:

different views of the security document Fig. 1 ;

3:

a schematic representation of a security document, which comprises a reflection volume hologram as a security feature and an apertured through openings formed in an opaque layer;

Fig. 4-6:

different embodiments of security documents with a CLI / MLI security feature and a see-through window formed through openings in an opaque layer;

Fig. 7:

a schematic representation of a security document with an internal lens structure for a CLI security feature and a through-window formed by a plurality of openings in an opaque layer;

Fig. 8:

a schematic representation of a manufacturing process of a security document; and

Fig. 9:

a schematic flow diagram of an embodiment of a verification method.

In Fig. 1 a security document 1 is shown schematically in perspective. This comprises a document body 2, which is made of a plurality of superimposed and interconnected originally self-supporting layers, in particular based on plastic. From a front side 11 to a rear side 12 of the document body 2, the latter is formed from a transparent layer 3, a transparent layer 4 provided for a laser marking, a flatly extended opaque layer 5 and a further transparent layer 6. It will be understood by those skilled in the art that security documents may be made from a different number of originally self-supporting layers. In the illustrated embodiment, the layers are similar to 3 to 6 in terms of their areal extent. The other embodiments may be different in terms of expansion.

Preferably, the layers are all based on the same plastic material, for example all made of a polycarbonate material. As a result, during a lamination process, a monolithic document body 2 can be manufactured, at which no phase transition boundaries between the material layers, which are originally made of different self-supporting layers of the same material, are recognizable. For example, become two identical transparent layers laminated on one another, the original material layer thicknesses can no longer be determined in the finished document body. If, for example, photosensitizers for improved laser marking or pigments for bringing about an opaque substrate layer are originally contained in the individual material layers, the material layers can of course also be determined in the finished document body on the basis of these additions. With regard to the plastic structure, which is decisive for a possible delamination, however, no phase boundaries can be determined in the monolithic document body.

However, other embodiments may provide that also plastic materials based on different polymers are joined together. Other joining methods such as gluing can be used individually or in combination in individual embodiments. In the document body, a contemplation-side-dependent security feature 14 is formed.

In the document body 2 of Fig. 1 is a so-called CLI security feature 13 is formed. The CLI security feature 13 comprises a lens structure 15 which is embossed in the transparent layer 3 facing the front side 11. For example, the lens structure may consist of parallel cylindrical lenses. These can all be designed identically or differently with regard to their optical properties. In addition, the CLI security feature 13 comprises an optically detectable information 20, which is formed, for example, via a laser marking in the transparent layer 4 specially prepared for this purpose. The optically detectable information 20 comprises a first information component 21, which is indicated by dots, and a second information component 22, which is indicated by crosses.

The information portions 21, 22 are arranged alternately nested. For example, the first piece of information 21 stores a letter "A" and the second piece of information 22 stores, for example, the letter "B". The two pieces of information can be introduced in a simple manner by utilizing the lens structure 15 in the document body 2 by means of laser radiation, which is irradiated from an irradiation direction A 23 and a Einstrahlrichtung B 24 for the corresponding information portions 21, 22. The incident laser radiation is focused in the document depending on the direction of irradiation at different positions, so that the partial information 21, 22 are stored nested depending on the direction of irradiation at different positions.

The CLI security feature 13 can be directly verified upon viewing the front panel 11. This means that viewing the security document 1 across the front page 11 is a direct consideration. Depending on the viewing directions, which are referred to as direct viewing direction A 25 and direct viewing direction B 26 and coincide correspondingly with the irradiation directions 24, 25, the different information portions can be perceived. When verifying in the direct view, a viewing direction-dependent information content of the stored information 21 is thus perceived. This represents a first optical effect which is viewing angle dependent.

In Fig. 2a and 2b the direct views on the direct observation directions A 25 and B 26 are presented accordingly. If a distance of the cylindrical lenses is selected to be correspondingly low, the fact that the information components originally consist of strips is not perceived by a human observer. Rather, the information components are perceived as complete graphical representations.

In the opaque layer 5, a plurality of apertures 30 is formed, which together form a see-through window 31. This see-through window 31 is arranged in the document body 2 relative to the CLI security feature 13 so that it is possible via the back 12 to detect through the see-through window 31 the stored information 20 of the CLI security feature 13. The considerations about the back side 12, which take place through the see-through window 31, ie through the apertures 30 in the opaque layer 5, are referred to as see-through views along the see-through viewing directions C 35, D 36. Regardless of the viewing direction, static information of the CLI security feature 13 is detected, which shows a superposition of the two letters "A" and "B" in diffuse illumination. However, if the document is viewed in transmitted light and illuminated with directional radiation from the direction originally the letter "A" was stored, ie illuminated from the direction from which the letter "A" when viewed directly through the front 11 through the lens structures 15 would be visible so an inverse "A" is perceived. This is in Fig. 2d shown. If the document is illuminated in transmitted light from the direction of directional light, from which, in direct viewing, the letter "B" would be seen, an inverse "B" would be perceived. this shows Fig. 2e , In Fig. 2c FIG. 2 shows the view of the security document 2 for viewing viewing directions C 35, D 36 over the back 12 of the security document 1 under diffuse illumination.

In Fig. 3 a further embodiment of a security document 1 is shown. The same technical features are provided in all figures with the same reference numerals. In Fig. 3 For example, the document body 2 has a reflection volume hologram 51 as contemplation-side-dependent security feature 14. When viewed directly via the front side 11, with a suitable irradiation of white light 52 under a viewing direction, an information 53 stored in the volume reflection hologram 51 is perceived in a spectral color, for example green. When looking through the through-window 30 formed through the apertures 30, complementary information 54 is detected under a suitable viewing direction in which the spectral portion which has contributed to the reconstruction of the hologram is removed from the light. Depending on the viewing side of the security feature 14 thus different optical effects are detected. It goes without saying for the person skilled in the art that embodiments are also possible in which the volume reflection hologram 51 is reconstructed, for example during the review examination, and the complementary information is perceptible in the direct examination.

In Fig. 4 Another security document 1 is shown schematically in a sectional view. In this embodiment, which also includes a CLI security feature 13, the stored information 20 is not introduced via a laser blackening of plastic, but via printing, for example, the underside of the transparent layer 3, in which the lens structure is embossed, before joining. This makes it possible to realize a colored CLI security feature 13. It should be noted at this point that the terms CLI and MLI, although actually created for laser-marked security features, are nowadays also used for viewing-angle-dependent security features that incorporate Lens structure and spaced therefrom stored optical information, which is not generated by a laser.

In Fig. 5 is a sectional view of a security document analogous to the security document according to Fig. 1 in which the information about laser marking is stored in the specially prepared laser marking substrate layer 4.

In the embodiment according to Fig. 6 For example, the opaque layer 5 with the apertures 30 formed therein is disposed between the lens structure 15 and the stored optically discernible information 20. In this embodiment, viewing through the back side 12, in which the perceived information is viewed through the see-through window 31, is considered to be a review. This shows a viewing angle dependent effect. By viewing through the front side 11, which is the direct view, only the stored information 20 is perceived as static information. For example, analogous to the embodiment according to Fig. 1 a superimposition of the letters "A" and "B" perceived, while in the review viewing viewing direction-dependent alternatively the letters "A" or "B" are perceived.

In Fig. 7 another embodiment is shown in which the lens structure 15 of the CLI security feature 13 is not formed on the uppermost substrate layer, ie on the front side of the security document 2. In this embodiment, the "free spaces" 61 created during the formation of the lenses of the lens relief in the substrate layer 4 are filled with a plastic material 62 whose refractive index deviates from that of the substrate layer 4 into which the lens relief is embossed. This substrate layer 4 is superimposed on another transparent layer 3, so that the front side 11 of the document 1 is smooth and flat. Preferably, the substrate layer 4, into which the lens structure 15 is originally embossed, is more highly refractive than the remaining substrate layers 3, 6 and than the plastic material 62 used to fill in the free spaces 61 created during embossing. However, embodiments are also possible in which the refractive indices are chosen to be opposite. The decisive factor for a lens effect is merely that the layer 4, in which the structures are embossed, and the plastic material 62, which fills the free spaces 61, have a different refractive index. With regard to the observable effects similar to the embodiment Fig. 7 those of FIGS. 1 . 4 and 5 ,

In Fig. 8 schematically the production of a security document is shown. Substrate layers 3-6 are provided on different rollers 101-104, following the substrate layers 3-6 of the embodiment Fig. 1 correspond. In this embodiment, for example, the prepared for a laser marking substrate layer 4 is printed in those areas where the CLI security feature is not to be formed later. The remaining substrate layers can also be printed. For this purpose, one or more pressure devices 121 may be provided. The apertures 30 are formed in the form of microperforations in a perforation device 131, for example via the irradiation of laser light, in the opaque, extensively extended substrate layer 5. In a laminating device 141, the various substrate layers 3-6 are joined together to form a monolithic layer composite 152. In a lens embossing device 151, microlenses of a lens structure 15 are impressed via a sonotrode on the front side 11 of the layer composite.

In a laser marking device 161, different information 20 about the microlenses of the lens structure 15 are stored in the document body from different directions. Finally, a separating device 171 separates the security documents 1 produced in this way, which in the case of the exemplary production process described below Fig. 1 same.

In the illustrated method, the openings are not filled. Since lamination takes place under preferably vacuum or negative pressure, this is possible. If the apertures are executed as microperforations, it has also been found that the apertures in the lamination process are at least not filled with opaque substrate material. In addition, it has been shown that the surfaces remain smooth and just in the area formed by the see-through window. In other embodiments, it can be provided that, for example in a doctoring station (not shown), transparent plastic material for filling in the perforations is doctored in before the lamination step.

In Fig. 9 schematically a flowchart of a verification method is briefly explained. First, a security document 201 is provided. The at least one security element, which shows different optical effects depending on the viewing side, is first of all detected in a direct view 202. Subsequently, a look through is made through the see-through window formed in the opaque layer 203. In a comparison step 204, in the information can be included in a database 207, the detected visual effects of the review and the direct viewing are compared and evaluated, and from this a verification decision is derived 205 and output 206.

It should be understood that the verification method and method of manufacture described herein are merely simple embodiments that may be refined by additional steps.

LIST OF REFERENCE NUMBERS

1

The security document

2

document body

3

transparent layer

4

provided for the laser marking layer

5

opaque layer

6

transparent layer

11

front

12

back

13

CLI security feature

14

View page-dependent security feature

15

lens structure

20

optically detectable information

21

first piece of information

22

second piece of information

23

Direction of irradiation A

24

Irradiation direction B

25

Direct Viewing A

26

Direct Viewing Direction B

30

perforations

31

Through window

35

Reviewing direction C

36

Reviewing direction D

41

View at direct viewing direction A

42

View at direct viewing direction B

47

optical background

51

reflection hologram

52

White light

53

information

54

complementary information

101-104

roll

121

print Setup

131

perforation

141

laminating

151

Lens embosser

152

laminate

161

Laser marking device

171

separating device

201-206

steps

207

Database

Claims (10)

1. A security document (1) comprising:

   a document body (2) having a face (11) and an opposite reverse (12), wherein the document body (2) is produced using at least one two-dimensionally extended, self-supporting opaque layer (5) which is integrated into the document body (2) between the face (11) and the reverse (12),

   and wherein at least one optically verifiable security feature (13, 14, 15) is formed, said security feature exhibiting different optical effects when viewed from the face (11) and when viewed from the reverse (12),

   characterised in that said security feature is formed in the document body (2) and in that a plurality of through-holes (30) are formed in the opaque layer (5) and arranged in such a way that the at least one optically verifiable security feature (13, 14, 15) can be optically detected both when viewed from the face (11) and when viewed from the reverse (12), wherein one of the two viewings is an indirect viewing (35, 36) through the through-holes in the opaque layer, and the other a direct viewing (23, 24) that is not effected through the through-holes, and the at least one optically verifiable security feature (13, 14, 15) is designed in such a way that different optical effects can be detected in the direct viewing (23, 24) and in the indirect viewing (35, 36), the difference of said optical effects not being caused by the presence of the opaque layer (5) and/or the through-holes (30).
2. The security document (1) of claim 1 wherein the at least one optically verifiable security feature (13, 14, 51) exhibits a viewing-angle dependence at least for one of the two viewings.
3. The security document (1) of claim 1 or 2 wherein a viewing-angle dependence of the indirect viewing (24, 25) and of the direct viewing (35, 36) is different.
4. The security document (1) of any one of the preceding claims wherein the at least one optically verifiable security feature (13, 14) comprises a plurality of lens elements (15) at a distance from which optically perceivable information (21) is stored in the document.
5. The security document of any one of the preceding claims wherein the at least one security feature (14) comprises a volume hologram (51), in particular a volume reflection hologram.
6. A method for the verification of a security document (1) which exhibits a document body (2) having a face (11) and an opposite reverse (12), comprising the steps:

   Detecting an optical effect of at least one security feature (14) when viewing the security feature (14) through the face (11), and detecting a further optical effect when viewing the same at least one security feature (14) through the reverse (12), with one of the two viewings being carried out as an indirect viewing (35, 36) in which the at least one security feature is viewed through a plurality of through-holes (30) in a two-dimensionally extended, self-supporting opaque layer (5) incorporated into the document body (2), and the other of the two viewings being carried out as a direct viewing (24, 25) in which the viewing is not effected through the plurality of through-holes (30) in the opaque layer (5), then comparing the detected optical effect and the further detected optical effect and deriving verification information.
7. A method for producing a security document (1) comprising the steps:

   Introducing a plurality of through-holes (30) into an opaque self-supporting layer (5); Incorporating the opaque layer (5) provided with a plurality of through-holes (30) into a document body (2) which has a face (11) and an opposite reverse (12);

   Configuring at least one optically verifiable security feature (14) in the document body in a manner in which the at least one optically verifiable security feature (14) is configured and arranged relative to the plurality of through-holes (30) such that an optical detection of the at least one optically verifiable security feature (14) is possible both when viewed through the face (11) and when viewed through the reverse (12), with one of the two viewings being an indirect viewing (35, 36) effected through the through-holes in the opaque layer and the other being a direct viewing (24, 25) not effected through the through-holes (30), and the at least one optically verifiable security feature (14) being configured so that it exhibits different optical effects when viewed through the face (11) and when viewed through the reverse (12) of the document body with the result that in direct viewing (24, 25) and in indirect viewing (35, 36) different optical effects are detectable, the difference of said optical effects not being caused by the presence of the opaque layer and/or the through-holes (30).
8. The method of claim 7 wherein the through-holes (30) are introduced into the opaque layer by way of laser perforation.
9. The method of claim 7 or 8 wherein the opaque layer (5) that is provided with the plurality of through-holes (30) is laminated with other layers (3, 4, 6) to form the document body (2) and the plurality of through-holes (30) is filled before or during lamination with a transparent or translucent material.
10. The method of any one of claims 7 to 9 wherein the plurality of through-holes (30) is applied in a grid pattern formed from hexagonal cells.

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