Method and device for producing a document and document

Abstract

A method for producing a document, wherein a first document layer (2) and at least one further document layer (3) are provided, wherein the at least one further document layer (3) is arranged above or below the first document layer (2), wherein the document layers (2, 3) are arranged relative to one another in such a way that an unjoined layer composite (1) provided from the first and the further document layer (2, 3) has at least one thickened or thinned partial region (14), wherein the layer composite (1) is joined, wherein the first document layer (2) and the at least one further document layer (3) consist of a laminatable material, wherein the joining is carried out by lamination, characterized in that the first document layer (2) has at least one printed region (6), wherein the document layers (2, 3) in the unjoined layer composite (2) are arranged relative to one another in such a way,that the thickened or thinned partial area (14) comprises at least a partial area of ​​the printed area (6).,

Description

[0001] The invention relates to a method and a device for producing a document, in particular a security document, and to such a document.

[0002] WO 2014 / 076046 A1 discloses a method for producing a multi-layer security product, comprising the method steps of providing an inlay layer or a layer composite containing the inlay layer and applying at least one personalized and / or individualized lamination layer to the inlay layer or the layer composite containing the inlay layer.

[0003] DE 10 2009 007 552 A1 also discloses a method for producing multi-layer security products, consisting of at least one card and at least one polymer film applied to at least one side of the card, which is provided as a roll and is provided with at least one security feature. Here, a roll of polymer film and at least one strip with an n-fold number of blanks are fed to a laminating station and laminated.

[0004] DE 10 2010 033 049 A1 discloses a method for producing a laminate composite for a security and / or value document, comprising at least a first polymer layer, a second polymer layer and a security feature to be laminated between the first and the second polymer layer.

[0005] DE 197 32 712 A1 discloses a particularly forgery-proof passport and a method for producing such passports.

[0006] DE 10 2015 003 187 A1 discloses a method for producing a multi-layer value document substrate, value document substrates obtainable by the method and value documents, in particular banknotes, comprising such a value document substrate.

[0007] US 2011 / 0089676 A1 discloses a method for checking the authenticity of a security document and a document comprising co-laminated layers.

[0008] In this process for producing multi-layer security documents, different layers can be joined and bonded together, for example by lamination.

[0009] Furthermore, it is known that attempts are being made to counterfeit security products, particularly valuables and / or security documents. Counterfeiting can be achieved by imitating process steps used in the production of the security product and / or by manipulating the finished security product.

[0010] The technical problem is to create a method and a device for producing a document, in particular a valuable and / or security document, as well as such a document, which increase the security of the document against forgery.

[0011] The solution to the technical problem results from the objects having the features of claims 1, 9 and 12. Further advantageous embodiments of the invention result from the subclaims.

[0012] A method for producing a document is proposed. The document can, in particular, be a valuable and / or security document. The document can be produced as a card body, in particular as a multilayer card body. In particular, the document or a part of the document can be made of plastic.

[0013] A security document can be any document that is a physical entity that is protected against unauthorized production and / or falsification by security features. Security features can be features that at least make falsification and / or duplication more difficult than simple copying. Physical entities that comprise or form a security feature are referred to as security elements. A security document can comprise multiple security features and / or security elements. Within the meaning of the definition given here, a security document can always represent or comprise a security element. Examples of security documents that also include valuable documents that represent value include passports, identity cards, driving licenses, identity cards, banknotes, postage stamps, credit cards, smart cards, and labels.Smart cards are security documents that contain a chip module that can exchange information with a verification device without contact.

[0014] In the method, a first document layer and at least one further document layer, which can also be referred to as a second document layer, are provided. A document layer can be designed, in particular, as a film. A document layer can be a single layer, in particular a single film.

[0015] Thus, the document to be produced can be a document made of or consisting of multiple layers. The first document layer and the at least one further document layer consist of a laminatable material. In this case, the first document layer can also be referred to as the first lamination layer, and the at least one further document layer can be referred to as the further lamination layer.

[0016] A laminatable material can, in particular, be a plastic material. Derivatives or combinations of the following plastics are particularly suitable: polycarbonate (PC), especially bisphenol A polycarbonate; polyethylene terephthalate (PET), its derivatives such as glycol-modified PET (PET-G); polyvinyl chloride (PVC); acrylonitrile butadiene styrene (ABS); thermoplastic elastomers (TPE), especially thermoplastic polyurethane (TPU). Other polyurethanes can also be used. Additionally, thermosetting resins and / or plastics or multi-component systems can be used.

[0017] Preferably, the first document layer is made of PC or PET, and the subsequent document layers are also made of PC or PET. In this case, the first and subsequent document layers can form a monolithic body after joining as explained below.

[0018] In addition to the first document layer and at least one further document layer, the document to be produced may also comprise further document layers, in particular further lamination layers. Thus, the first document layer may be part of a layer composite, which may comprise another document layer in addition to the first document layer.

[0019] Additional document layers may also be protective layers or an inlay layer, which is described, for example, in the previously explained WO 2014 / 076046 A1.

[0020] The document, in particular a document layer, further in particular the first and / or further document layer, can have or contain at least one piece of detectable information. This is also referred to below as document-specific or layer-specific information.

[0021] The information may have a predetermined representation, in particular an optical, particularly graphic, representation, an electrical representation, or a magnetic representation. The representation may also be detectable, in particular with a suitable detection device. The information may be encoded by the representation. The information may also be determinable depending on the representation.

[0022] Information can be provided, for example, by at least one graphic element, e.g., by at least one character or a photograph. Information can also be provided or encoded by data stored in a storage device of the document, in particular an inlay layer. Information can also be provided by a hologram.

[0023] The information can be captured by a corresponding capture device and / or by a human user. The information can be captured optically, e.g., by an image capture device or visually. However, it is also possible for the information to be captured non-optically, e.g., electrically, mechanically, inductively, or capacitively.

[0024] The information may constitute a security feature of the document or the document layer, or a part thereof. Security features of or for documents are known to those skilled in the art and include, but are not limited to, photographs, holograms, kinegrams, digital watermarks, interference patterns (copy traps), and transmitted light registers.

[0025] A document layer, in particular the first document layer, can be, for example, a personalized and / or individualized lamination layer. A personalized and / or individualized lamination layer can refer to a layer that contains information that individualizes the security product and / or information that personalizes a person authorized to manage the document. This information can be contained, for example, as security features or elements in or on the personalized and / or individualized document layer. Such information can be, for example, a name, a document or serial number, a signature, a photograph, or a hologram.

[0026] The information of the personalized and / or individualized document layer can be incorporated into or on the document layer in various ways.

[0027] Thus, a document layer can be a print layer, with information being printed on or in the document layer formed as a print layer. Corresponding printing processes, in particular gravure, letterpress, digital, inkjet, and offset printing processes, are known to those skilled in the art.

[0028] Alternatively, the information can be engraved, for example, using a laser engraving process. Of course, other methods for incorporating or attaching the information into the personalized and / or individualized document layer are also conceivable.

[0029] Preferably, but not necessarily, the first document layer is a printed layer, with information, in particular optically detectable information, and more particularly visually detectable information, being printed on or into the first document layer. In particular, this information can be the personalizing and / or individualizing information explained above.

[0030] Furthermore, at least one further printing layer is arranged above or below the first printing layer.

[0031] In this case, directional information such as “above” or “below” can refer to a document layer-specific vertical direction. This vertical direction can be oriented perpendicular to a, in particular non-curved, surface of the document layer, in particular a bottom or top surface. An upper side of the document layer can refer to a side which, in the finished state of the document, is oriented towards the front of the document. Accordingly, a bottom side of the document layer can refer to a side which, in the finished state of the document, is oriented towards the back of the document. Furthermore, the vertical direction can be oriented from the bottom of the document layer to the top of the document layer.

[0032] A document layer-specific or document-specific coordinate system can be defined by this vertical direction as well as a longitudinal direction and a lateral direction. The bottom and / or top surface of the document layer, or a front and back side of the document, can be oriented parallel to a plane spanned by the longitudinal and lateral directions.

[0033] The vertical direction, the longitudinal direction, and the lateral direction can each be oriented perpendicular to one another. In particular, the longitudinal direction can extend parallel to a longitudinal edge of the document layer / document, and the lateral direction can extend parallel to lateral edges of the document layer / document.

[0034] In other words, a length of the document layer / document may be a dimension along the longitudinal direction, and a width of the document layer / document may be a dimension along the lateral direction. A thickness of the document layer / document may be a dimension of the document layer along the vertical direction.

[0035] The first document layer can have a rectangular edge profile. This can be present in a projection plane oriented perpendicular to the previously explained vertical direction. The first document layer can have a constant or varying thickness. The thickness can range from 200 µm to 750 µm.

[0036] The remaining document layer can also have a constant or varying thickness. The thickness can range from 200 µm to 750 µm.

[0037] The additional document layer can, for example, be transparent or translucent. Alternatively, the additional document layer can have a predetermined color. The additional document layer can also be opaque. Furthermore, the additional document layer can be formed from a material with a predetermined density. The density can differ from the density of the material of the first document layer. In particular, the density of the additional document layer can be lower than the density of the first document layer.

[0038] In particular, the additional document layer can be arranged on or at the top surface of the first document layer. Alternatively, the additional document layer can be arranged on or at the bottom surface of the first document layer. If the additional document layer is arranged above a region of the first document layer that has or contains information, the additional document layer can preferably be transparent. If the additional document layer is arranged below such a region of the first document layer, the additional document layer can preferably be opaque.

[0039] This will provide a layered assembly comprising the first document layer and the additional document layer arranged above or below the first document layer. The layered assembly provided in this way can also be referred to as an unjoined layered assembly.

[0040] Furthermore, to create the unjoined layer composite, the additional document layer can be (pre-)attached to the first document layer. This can be achieved, for example, by ultrasonic stapling. Of course, other fastening methods are also conceivable, such as heat welding.

[0041] Furthermore, the document layers are arranged relative to one another in such a way that the unjoined layer composite provided from the first and the further document layer has at least one thickened or thinned partial area.

[0042] In particular, the document layers can be arranged and / or configured relative to one another such that the thickened or thinned partial region has a predetermined spatial position, a predetermined size, and / or a predetermined shape. In other words, properties of the predetermined partial region, in particular a size, a shape, and a spatial position of the partial region, can be predetermined.

[0043] A thickened partial region, which can also be referred to as a thickened section, can refer to a partial region of the unjoined layer composite that has a thickness that is greater than an average thickness of the unjoined layer composite. Alternatively or cumulatively, a thickened partial region can refer to a partial region in which a thickness is greater than in an adjacent partial region of the unjoined layer composite or than in an area outside the partial region. In particular, a thickness of the unjoined layer composite can increase at a transition to a thickened partial region, e.g., abruptly, linearly, or continuously. A thickness in the thickened partial region can be greater than an average thickness of the unjoined layer composite or a thickness outside the thickened partial region by more than a predetermined percentage, e.g., by more than 10%, more than 30%, or more than 50%.In a thickened partial area, the thickness of the unjoined layer composite can, for example, be in a range from 400 µm (exclusive) to 2,250 µm (inclusive).

[0044] Accordingly, a thinned partial region, which can also be referred to as a thinned section, can refer to a partial region of the unjoined layer composite that has a thickness that is smaller than an average thickness of the unjoined layer composite. Alternatively or cumulatively, a thinned partial region can refer to a partial region in which a thickness is smaller than in an adjacent partial region of the unjoined layer composite or than in an area outside the partial region. In particular, a thickness of the unjoined layer composite can decrease at a transition to a thinned partial region, e.g., abruptly, linearly, or continuously. A thickness in the thinned partial region can be smaller than an average thickness of the unjoined layer composite or a thickness outside the thinned partial region by more than a predetermined percentage, e.g., by more than 10% or more than 30%, but less than 50%.In a thinned sub-area, a thickness of the unjoined layer composite can, for example, be in a range from 280 µm (inclusive) to 1,050 µm (inclusive).

[0045] A thickness in the thickened or thinned partial area may be outside the tolerance limits of a layer composite provided without a thickened or thinned partial area.

[0046] A thickening can be formed, for example, by an elevation, a projection or a raised partial area on a surface of the first document layer and / or on a surface of the further document layer, the surfaces being mutually facing surfaces in the unjoined layer composite.

[0047] A thinning can be formed, for example, by a depression or a recess on a surface of the first document layer and / or on a surface of the further document layer, the surfaces being mutually facing surfaces in the unjoined layer composite.

[0048] It is further possible for at least one of the document layers to be configured such that, in a desired relative arrangement, the unjoined layer composite has at least one thickened or thinned partial region. For example, the first document layer can have at least one thickened or thinned partial region. Alternatively or cumulatively, the further document layer can have a thickened or thinned partial region. However, it is also possible for the first and the further document layer to each have a constant thickness, wherein, however, the further document layer has a smaller width and / or a smaller length than the first document layer.

[0049] In particular, the further document layer is arranged and / or the further document layer is designed in such a way that the unjoined layer composite provided from the first and the further document layer has at least one thickened or thinned partial region.

[0050] The thickness of the unjoined layer composite can be the sum of the thickness of the first document layer and the thickness of the further document layer in the unjoined state. In particular, the thicknesses of partial regions / sections of the document layers arranged one above the other in the vertical direction can be summed to determine the thickness of the unjoined layer composite.

[0051] At least one third document layer can also be arranged above the uppermost document layer of the unattached layer composite. Alternatively or cumulatively, at least one third document layer can be arranged above the lowermost document layer of the unattached layer composite. This third document layer can have the same width and / or the same length and / or the same thickness as the first document layer. Thus, the unattached layer composite can comprise more than two document layers. In particular, the previously explained further document layer (second document layer) can be arranged in the unattached layer composite between the first and third document layers.

[0052] Next, the unjoined layer composite is joined. This creates a joined layer composite. The joining can be carried out, in particular, by a method for producing a material-to-material bond between the first and the further document layer. The joining can be carried out using at least one predetermined joining parameter, for example, a joining temperature, a joining pressure, and / or a joining time.

[0053] Preferably, the joining can be achieved by lamination. During lamination, pressure from a predetermined pressure range can be applied to the layered composite. Furthermore, thermal energy can be transferred to the layered composite. The lamination can therefore be either hot lamination or cold lamination.

[0054] The joined layer composite can be designed as a card body or as a card body part.

[0055] After joining, the layer composite can have a constant thickness, in particular no thickened or thinned areas.

[0056] During joining, the changing thickness of the unjoined layer composite can be changed to a constant thickness. During joining, a material shift or displacement, in particular a local material displacement, can occur at least in at least one partial area of ​​the layer composite, in particular in at least one partial area of ​​the first and / or the further document layer. This can occur in particular in a thickened or thinned partial area or in an area of ​​the layer composite encompassing this partial area.

[0057] The displacement of material can also change information, in particular layer-specific information, and furthermore in particular an information content of this information. A change in the information can in particular refer to a change in the representation of the information. The representation can, for example, be a graphical representation, although the invention is not limited to graphically representable information. In other words, a representation of the information in or on the unjoined layer composite can differ from a representation of the information in the joined layer composite. If such a graphical representation is changed, the appearance of the information can be altered.

[0058] The change can be a targeted change, in particular a change to produce a desired piece of information, e.g., a desired representation of the information. In particular, the change can be made in such a way that a desired target representation, e.g., a graphic target representation, is produced from an initial representation, e.g., a graphic initial representation, of the information.

[0059] For example, joining can change the position and / or orientation of at least one spatial region of the document layer, wherein the spatial region contains or provides at least part of the information. The position and / or orientation can change in a coordinate system fixed to the document layer.

[0060] Furthermore, joining the unjoined layer composite can result in a geometric transformation of at least one spatial region of the document layer, wherein the spatial region contains or provides at least part of the information or its representation. The geometric transformation can, in particular, be a defined geometric transformation, in other words, a targeted geometric transformation.

[0061] In particular, the geometric transformation can be a transformation that creates a desired target representation, e.g., a graphic target representation, from an initial representation of the information, e.g., from a graphic initial representation. If the information is, for example, printed information, in particular characters or part of a photograph, then, as explained in more detail below, a geometric transformation of the printed information can be achieved by joining.

[0062] As explained in more detail below, the document layers can also be arranged relative to one another and / or at least one of the document layers can be designed in such a way that the joined layer composite has a changing density, in particular optical density.

[0063] For example, the joined layer composite can have a partial region with a predetermined density, wherein this density is higher or lower than an average density of the joined layer composite. Alternatively or cumulatively, the joined layer composite can have at least one partial region with a density that is higher or lower than a density outside the partial region.

[0064] Such a partial area can form a watermark in the joined layer composite. Thus, the partial area can be detected and verified using incident light-based or transmitted light-based methods.

[0065] In particular, the thickened or thinned portion of the unjoined layer composite can be provided in such a way that joining results in a desired, in particular targeted, information change. In other words, a thickness profile of the unjoined layer composite can be selected in such a way that joining results in a desired, in particular targeted, information change.

[0066] The change in information can depend, among other things, on properties, in particular material properties, the document layers and joining parameters.

[0067] This advantageously results in a higher security against forgery of the document produced as proposed.

[0068] Due to the previously explained information change due to joining, it can be ensured that the layer composite contains information after joining that differs from the information before joining. In particular, the information after joining can correspond to a target information, while the information before joining differs from the target information by more than a predetermined amount.

[0069] Thus, the authenticity of the joined layer composite or of a document comprising this joined layer composite can be verified if the information change does not deviate from a target change by more than a predetermined amount and / or if the information in the joined layer composite corresponds to target information. The authenticity of the joined layer composite or of a document comprising this joined layer composite cannot be verified if the information change deviates from the target change by more than a predetermined amount and / or if the information in the joined layer composite does not correspond to the target information.

[0070] This can be clearly explained using the example of visually perceivable information. In an unstitched layered composite, the information may have an initial representation, in particular a representation that deviates from the target representation, e.g., a distorted representation. Only if the document layers in the unstitched layered composite are arranged in a predetermined manner relative to one another and / or are designed in a predetermined manner and / or are joined using predetermined joining parameters, can the target representation of the information, e.g., a non-distorted representation, be created from the initial representation by joining.If the document layers in the unjoined layer composite are not arranged in a predetermined manner relative to one another and / or the document layers are not formed in a predetermined manner and / or the document layers are not joined with predetermined joining parameters, the desired representation of the information cannot be created by joining from the initial representation.

[0071] The target information can be known in advance or can be determined.

[0072] For example, the target information can be present in or on the joined layer composite or in or on a document that comprises this layer composite, in particular in a representation that is different from the representation that can be changed by joining. For example, the target information can also be present multiple times in or on the joined layer composite or in or on a document that comprises this layer composite, in particular with different representations. The target information can thus be captured by the joined layer composite. The target information can be information that does not change or can be changed by joining. For example, it is conceivable that the target information can be stored and retrieved in a storage device of the document or the layer composite, e.g. a storage device of an inlay layer.

[0073] Alternatively, the target information can be stored and retrieved, for example, in a storage device external to the system.

[0074] If the information is, for example, a biometric feature, e.g., an interpupillary distance, which can be determined based on a graphic representation of a photograph that changes during the joining process, a target value or a target value range of this feature can be stored in a memory device of the document or in a memory device external to the document in a retrievable manner. If the value of the biometric feature, which is determined based on the graphic representation of the photograph after joining, deviates from the target value by more than a predetermined amount or lies outside the target value range, the authenticity of the document with the joined layer composite cannot be verified.If the value of the biometric feature, which is determined depending on the graphic representation of the photograph after joining, does not deviate from the target value by more than a predetermined amount or if it lies within the target value range, the authenticity of the document with the joined layer composite can be verified.

[0075] In other words, the information change and / or the result can be used to verify the document. In particular, the document can be classified as a forgery if information in the document with the joined layer composite deviates from the predetermined target information.

[0076] Furthermore, the document can be identified as a forgery if no evidence of the first and the further document layer, in particular of material from the first and the further document layer, and / or evidence of a predetermined material distribution can be provided in a cross-section of the document.

[0077] In other words, producing a document with desired properties is made more difficult because a forger must have information about the configuration of the document layers, in particular their geometric configuration, material-specific configuration, and other properties of the document layers, as well as information about the arrangement of the additional document layer relative to the first document layer in order to provide the desired information during assembly. Following the proposed manufacturing process, forgery is made more difficult because it is no longer possible to simply separate the document into the first and additional document layers.

[0078] According to the invention, the first document layer has at least one printed area. Thus, the first document layer can be designed as the previously explained printed layer. Furthermore, to produce the unjoined layer composite, the document layers are arranged relative to one another such that the thickened or thinned partial area comprises at least a partial area of ​​the printed area. For example, a further document layer can be arranged above or below at least a partial area of ​​the printed area. In this case, a (maximum) width of the further document layer can be less than or equal to a maximum width of the printed area. Alternatively or cumulatively, a (maximum) length of the further document layer can be less than or equal to a maximum length of the printed area.In other words, the additional document layer can be arranged within the printed area in a common projection plane, which can be oriented perpendicular to the vertical direction. The area of ​​the additional document layer in the common projection plane can be smaller than or equal to the area of ​​the printed area.

[0079] However, it is also conceivable that the area of ​​the further document layer in the common projection plane is larger than the area of ​​the printed area, whereby the printed area in the common projection plane is arranged within the further document layer.

[0080] In this case, material displacement can occur during the joining process in at least a portion of the printed area. This, in turn, can alter the printed information. In particular, the representation and thus the appearance of the printed information can be altered by the joining process.

[0081] Preferably, at least part of the information can be geometrically transformed. The geometric transformation can be a defined, in particular predetermined, geometric transformation.

[0082] The printed area may contain or contain, in particular, a piece of printed information that can be captured, in particular optically captured, and furthermore, in particular machine- and / or visually captured. For example, the information may be image-based capture information. For this purpose, it may be necessary to create an image of the printed area. However, the printed information may also be information that can be visually captured by a human.

[0083] Thus, the arrangement of the additional document layer advantageously allows printed and thus easily detectable information to be altered during assembly. This also makes any changes to the information easy to detect. In particular, the printed information may have a different appearance after assembly. Based on this change, as previously explained, an authenticity check, in particular a verification, of the document can be performed.

[0084] In a further embodiment, a maximum width of the further document layer is smaller than a maximum width of the first document layer. Alternatively, but preferably cumulatively, a maximum length of the further document layer is smaller than a maximum length of the first document layer. In this case, the length and width of the document layers are each recorded along the same spatial direction. In other words, the further document layer has a smaller dimension than the first document layer. In this case, both the first and the further document layer can have a constant thickness.

[0085] Alternatively, it is possible for the document layers to have the same width and the same length, but at least one of the document layers, in particular the further document layer, to have a varying thickness.

[0086] However, by providing the further document layer with smaller dimensions compared to the first document layer, it is advantageously easier to produce the further document layer, in particular by extrusion.

[0087] In a further embodiment, the additional document layer has a rectangular edge contour. The edge contour can be defined in a projection plane oriented perpendicular to the previously explained vertical direction.

[0088] This advantageously results in a simple design of the further documentation.

[0089] Alternatively, the additional document layer can have a circular or oval edge. This advantageously results in more uniform material displacement during joining, which in turn enables a more reliable production of the desired document properties after joining.

[0090] However, it is also possible for the edge contour of the additional document layer to have a further geometric shape, in particular a freeform shape. The geometric shape of the additional document layer and also the thickness can be selected in such a way that the desired information change occurs upon joining. Thus, the geometric configuration, in particular the geometric configuration of the border, of the additional document layer can be determined through simulation or testing.

[0091] In a preferred embodiment, a photograph or part thereof is printed in the printed area. The photograph can be printed using an offset printing or an inkjet printing process. Of course, other printing processes are also applicable.

[0092] The photograph can, in particular, be an image of the person authorized to keep the document. The photograph, in a desired appearance, can enable the determination of a value for at least one biometric characteristic.

[0093] As explained above, a target value or target value range of the biometric feature can then also be encoded in another form in or on the document, for example, in an electrical or electronic storage device of the document. Such a storage device can be read using wireless methods, for example, via RFID-based methods.

[0094] A target value of the biometric feature can also be determined by generating a facial image of the person authorized to manage the document, e.g. by means of an image capture device, whereby the target value of the biometric feature is determined depending on the facial image generated.

[0095] For example, an interpupillary distance, also known as interpupillary distance, can be determined as a biometric characteristic. For example, a target range for an interpupillary distance can be in a range of 50 mm to 75 mm.

[0096] This advantageously results in a particularly reliable authenticity check of information that can be changed by joining and thus increased security against forgery.

[0097] In a further embodiment, the document layers in the unjoined layer composite are arranged relative to one another in such a way that at least a partial region of the layer composite is deformed by the joining process in such a way that information in or on the unjoined layer composite is modified, in particular, specifically modified. The information can be contained in or on a thickened or thinned partial region of the layer composite.

[0098] The information in or on the unjoined layer composite can be layer-specific information of the first or further document layer or information provided by the combination of both document layers.

[0099] In addition to the relative arrangement, it may also be necessary to select the properties of the document layers, in particular their material properties and / or geometric properties, and / or joining parameters in such a way that the targeted change is achieved.

[0100] In particular, the information in or on the unjoined layer composite can be information that deviates from the desired information, in particular a representation that deviates from a desired representation. This can be changed by joining into desired information, in particular into a desired representation. Information that deviates from the desired information can in particular also be referred to as distorted information. Desired information can also be referred to as corrected information. The information content of distorted information can deviate from the desired information content by more than a predetermined amount or lie outside a permissible range of information content. The desired information content or the range can be known in advance or determinable.

[0101] For example, if the representation of the information comprises a character of a predetermined font with a predetermined font size, the target representation of the character, i.e., a target appearance, may have previously known properties. A distorted representation may have properties that deviate from the target properties. A distorted representation may have the target properties.

[0102] If the representation of the information enables the determination of a value of a characteristic, in particular a biometric characteristic, a target value or a target value range may be known or determinable, as explained above. A distorted representation of the information in this case may refer to a representation that enables the determination of a value of the characteristic that deviates from the target value by more than a predetermined amount or lies outside the target value range.

[0103] This advantageously results in increased security against forgery, since a forger can only create the desired representation of information if they have information about the relative arrangement of the document layers and, if applicable, the properties of the document layer and the joining parameters. Thus, if a forger obtains the first document layer, for example, in the form of a blank, it becomes more difficult to produce the desired document.

[0104] In a further embodiment, the information is modified by a geometric transformation of at least a partial area. In particular, this can change a graphical representation of the information, i.e., its appearance.

[0105] The geometric transformation can be caused by the joining, in particular by the material displacement. The geometric transformation can in particular be a predefined geometric transformation. A geometric transformation can be carried out according to a predetermined transformation rule, in particular a rule for an affine or bilinear transformation. A geometric transformation can in particular result in a compression and / or extension and / or translation and / or rotation and / or mirroring and / or scaling and / or shearing of the information.

[0106] A geometric transformation can change the spatial position, i.e., the position and / or orientation, of the information or a sub-area containing the information. In other words, joining results in a targeted deformation of a sub-area of ​​the first document layer and / or the further document layer.

[0107] The geometric transformation can, in particular, be carried out in such a way that an appearance deviating from the desired appearance is transformed into the desired appearance by joining. For example, graphic information with a distorted appearance can be present in the unjoined layer composite, with the appearance being corrected by joining. The distorted appearance can, for example, be a distorted character or a distorted photograph.

[0108] The change in the form of geometric information advantageously enables a simpler production or provision of the first and / or further document layer with distorted information, since due to the previously known transformation the information can be introduced into the first and / or further document layer in such a way that distorted information is generated by subsequent joining.

[0109] In a further preferred embodiment, information in or on the unjoined layer composite that differs from the desired information is changed into the desired information by joining. In other words, a representation of the information that deviates from the desired representation can be changed into the desired representation by joining. In still other words, distorted information can be corrected by joining. This and corresponding advantages have been explained previously.

[0110] In particular, the information in or on the unjoined layer composite can be information that is geometrically transformed relative to the target information. In particular, the representation of the information in or on the unjoined layer composite can be determined by a geometric transformation of the target representation. Joining can result in a reverse transformation. In other words, the document layers can be arranged relative to one another in such a way that at least a partial area of ​​the layer composite is deformed in such a way that the information in or on the unjoined layer composite is reverse-transformed into target information.

[0111] To determine the representation of the information in or on the unjoined layer composite for a manufacturing phase, an unjoined layer composite with a target representation of the information can be provided in a determination phase according to the previous explanations. The layer composite can then be joined, in particular with specified joining parameters.

[0112] After joining, the representation of the information, now modified by joining, can be captured, and a deviation from the original target representation can be determined, for example, based on an image. Then, at least one parameter of a geometric transformation, which can also be referred to as a forward transformation, can be determined, through which the target representation was transformed into the modified representation by joining.

[0113] Depending on the forward transformation determined in this way, a back transformation can then be determined, for example as a transformation inverse to the forward transformation.

[0114] For a manufacturing phase, an unjoined layer composite with a back-transformed representation of the information can then be provided, where the back-transformed representation denotes a representation that was determined by a geometric transformation of the target representation according to the back transformation determined in the determination phase.

[0115] By joining during production, the re-transformed representation is then transformed back into the target representation.

[0116] For example, the deviating representation can be captured by an image capture device, with a computing device determining the at least one transformation parameter and the corresponding inverse transformation. Furthermore, the computing device can control a device for inserting or applying the information, for example, a printing device, such that the information is inserted or applied in or onto one of the document layers in a correspondingly inversely transformed manner.

[0117] This advantageously results in easy verification of the produced document with increased security against forgery, particularly since the information is available after joining in a target representation that can be easily evaluated by a corresponding verification system or a user. For example, it is easy to verify whether a photograph is present in the document in a representation that differs from the target representation.

[0118] In a further embodiment, the layer composite has a changing density after joining.

[0119] In particular, after joining, the layer composite can have a density in a predetermined sub-region that is higher or lower than an average density of the layer composite. Alternatively or cumulatively, a sub-region can refer to a sub-region in which a density is higher or lower than in an adjacent sub-region of the joined layer composite or than in an area outside the sub-region. In particular, a density of the joined layer composite can increase or decrease at a transition to a sub-region, e.g., abruptly, linearly, or continuously. A density in such a sub-region can be higher or lower than an average density of the joined layer composite by more than a predetermined percentage, e.g., by more than 10%.

[0120] In this case, the partial area of ​​the joined layer composite with a higher or lower density can be a partial area of ​​the layer composite which, before joining, was a thickened or thinned partial area of ​​the unjoined layer composite, comprised such a thickened or thinned partial area or was comprised by such a partial area.

[0121] The predetermined partial region with a higher or lower density can have a predetermined geometric shape. For example, the partial region can have a rectangular, circular, or oval edge profile, in particular in a cross-sectional plane oriented perpendicular to the vertical direction explained.

[0122] The changing density can, in particular, provide a watermark. A watermark can be detected, in particular, by transmitted light illumination, for example, visually by a user or by a suitably designed detection device. In other words, a watermark is created by joining a layer composite with a changing density.

[0123] This advantageously results in further increased security against forgery. In particular, after joining, the density of the produced document can be determined, particularly a spatial density distribution. Depending on the properties of the first and subsequent document layers, as well as the relative arrangement of the document layers prior to joining, a specific sub-area with a predetermined density and, if appropriate, a predetermined geometric shape can be created by joining. If the finished document has such a sub-area, the document can be verified.

[0124] Further proposed is a device for producing a document, in particular a security document. The device serves to carry out a method according to one of the embodiments explained in this disclosure. In particular, the device is designed such that such a method can be carried out using the device.

[0125] The device comprises a first device for positioning a first document layer. The positioning device can, in particular, change a spatial position, i.e., a position and / or orientation, of the first document layer. The positioning device can, for example, be a conveyor belt or comprise such a conveyor belt.

[0126] Alternatively or cumulatively, the device comprises a further device for positioning a document layer, in particular the further document layer.

[0127] The positioning device(s) can be used to establish a desired relative position between the two document layers. In particular, the positioning device(s) can be used to arrange the additional document layer below or above the first document layer, in particular in a desired relative position.

[0128] The device further comprises a joining device.

[0129] It is conceivable that the device further comprises a device for (pre-)attaching the additional document layer to the first document layer. This can be designed, for example, as a device for ultrasonic stapling.

[0130] Thus, the at least one further document layer can be arranged above or below the first document layer by means of the proposed device, in particular in a desired relative position.

[0131] According to the invention, the document layers can be arranged relative to one another in such a way that an unjoined layer composite provided from the first and the further document layer has at least one thickened or thinned partial region.

[0132] Furthermore, at least one of the document layers can be designed such that the unjoined layer composite has at least one thickened or thinned partial region in a desired relative arrangement, in particular with a desired geometric configuration and / or in a desired position.

[0133] Furthermore, the layer composite can be joined, in particular by means of the joining device, in particular a laminating or covering device.

[0134] The device advantageously enables a method according to one of the embodiments explained in this disclosure to be carried out, thus enabling a document with improved forgery security to be produced. This has already been explained above.

[0135] In a further embodiment, the device comprises at least one device for arranging detectable information in or on the first and / or the further document layer. The information can, for example, be printed information. This can, for example, comprise at least one step character or a graphically representable symbol and / or (part of) a photograph. The arranging device can, for example, be a printing device. Of course, other devices, for example embossing devices, can also be used to arrange detectable information in or on one of the document layers.

[0136] In particular, the information can be arranged in a distorted representation in or on a document layer. This has already been explained above. Providing the device for arranging detectable information advantageously results in a simpler production of a document with increased forgery security.

[0137] In a further embodiment, the device comprises at least one computing device for calculating an arrangement of the information on or in the first document layer and / or further document layer such that target information is generated by the joining. In particular, an undistorted representation of the information can be generated by the joining. This and corresponding advantages have already been explained above. The computing device can be designed as a microcontroller or comprise one.

[0138] A document is also proposed. The document is produced by a method according to one of the embodiments explained in this disclosure. The document can also be produced by a device according to one of the embodiments explained in this disclosure.

[0139] The document exhibits a varying density, created by joining a first and at least one further document layer. This and the corresponding advantages have already been explained above.

[0140] Alternatively or cumulatively, the document has captureable information that has been geometrically transformed by joining the first and at least one further document layer, in particular from a representation that deviates from a target representation into the target representation. In particular, the document can have at least one document layer with a printed area. Before joining, the printed area can be arranged in a plane of the document layer, for example on a top side or on a bottom side of the document layer. After joining, a dimension of this plane, in particular a length, a width and / or a thickness of this plane, can change. For example, information that was printed on a top side or bottom side of the first document layer can be displaced into the document body by joining.

[0141] The invention is explained in more detail using an exemplary embodiment. The figures show: Fig. 1 a schematic cross section through a layer composite before joining according to a first embodiment, Fig. 2 a schematic cross section through a layer composite before joining according to a further embodiment, Fig. 3 a schematic cross-section through a layer composite after joining, Fig. 4 a schematic plan view of a layer composite before joining, Fig. 5 a schematic plan view of the Fig. 4 shown layer composite after joining, Fig. 6 a schematic plan view of a layer composite after joining according to a further embodiment, Fig. 7 a schematic flow diagram of a method according to the invention, Fig. 8 shows a further schematic flow diagram of a method according to the invention and Fig. 9 a schematic block diagram of a device according to the invention.

[0142] In the following, the same reference symbols designate elements with the same or similar technical features.

[0143] In Fig. 1 shows a schematic cross-section through an unjoined layered composite 1 prior to joining, in particular prior to lamination. The layered composite 1 can be a document produced according to the invention or a part of such a document. The layered composite 1 comprises a first document layer 2 and a further document layer 3. It is further shown that a printed area 5 is arranged on an upper side 4 of the first document layer 2. Also shown are a vertical direction z and a longitudinal direction x of a document-fixed coordinate system and a document-fixed coordinate system, respectively.

[0144] The further document layer 3 is arranged on a bottom side 5 of the first document layer 2. An upper side of the further document layer 3 rests against this bottom side 5.

[0145] It is shown that a thickness D1 of the first document layer 2 along the vertical direction z can be in a range of 400 to 600 µm. A thickness D2 of the further document layer 3 can also be in the stated range.

[0146] It is further shown that a length L1 of the further document layer 3 along the longitudinal direction x is smaller than a length L2 of the first document layer 2. It is not shown that a width of the further document layer 3 along a lateral direction y (see Fig. 4) can also be smaller than a width of the first document layer 2. The lateral direction y can enclose a right angle with the vertical direction z and the longitudinal direction x, whereby the coordinate system consisting of the directions x, y, z can be a Cartesian coordinate system.

[0147] The further document layer 3 can be made of a predetermined material, in particular PC or PET. The first document layer 2 can also be made of a predetermined material, for example PC or PET.

[0148] In Fig. 1 shows that the additional document layer 3 is strip-shaped. Of course, the additional document layer 3 can also have a different geometric shape.

[0149] The unjoined layer composite 1 has a varying thickness. The thickness changes along the longitudinal direction x and the lateral direction y. In particular, the unjoined layer composite 1 has a thickened partial region 14. This is formed by the partial region in which the further document layer 3 is arranged on the underside 5 of the first document layer 2. In particular, the thickness of the layer composite is greater in the region in which the further document layer 3 is arranged on the underside 5 of the first document layer 2 than in the regions in which no further document layer 3 is arranged on the underside 5 or the top side 4 of the first document layer 2.

[0150] The thickness of the unjoined layer composite 1 in the thickened partial area 14 corresponds to the sum of the thicknesses D1, D2 of the first document layer 2 and the further document layer 3. Outside the thickened partial area 14, the thickness of the layer composite 1 corresponds to the thickness D1 of the first document layer 2.

[0151] In Fig. 2 shows a schematic cross section through a layer composite 1 in a further embodiment. Here, it is shown that the further document layer 3 has a changing thickness along the vertical direction z. In particular, the further document layer 3 has a thickened partial region with a thickness D2' that is greater than a thickness D2 of the further document layer 3 outside this thickened partial region. Furthermore, the further document layer 3 can have the same length L and the same width as the first document layer 2. It is also shown that the further document layer 3 is arranged on the underside 5 of the first document layer 2. In this case, a thickened partial region 14 of the unjoined layer composite 1 is formed by the partial region in which the thickened region of the further document layer 3 is arranged on the underside 5 of the first document layer 2.

[0152] Both in Fig. 1 as well as in Fig. 2 shows that a printed area 6 is arranged in the thickened area 14, in particular on the upper side 4 of the first document layer 2 in this thickened area 14, of the unjoined layer composite 1.

[0153] Furthermore, the unjoined layer composite 1, which is Fig. 1 or Fig. 2 is shown schematically, joined, in particular laminated.

[0154] In Fig. 3 shows a schematic cross-section through a joined layer composite 1, i.e. a layer composite after joining. Fig. 3 can be produced in particular by joining the Fig. 1 shown unjoined layer composite 1 with specified joining parameters.

[0155] It is shown that the layer composite 1 has a constant thickness D after joining. Dashed lines indicate a partial area of ​​the layer composite that is created by the penetration of the additional document layer 3 into the first document layer 2. The illustration is only schematic and serves to visualize a material displacement of material from the first document layer 2 by material from the additional document layer 3 in the partial area 14 that was thickened before joining.

[0156] Due to the penetration of the further document layer 3 into the first document layer 2 during joining, material displacement can occur in a partial area of ​​the first document layer 2, in particular in a partial area that lies below the printed area 6 along the vertical direction z. The material can be displaced in or against the lateral direction y and / or in or against the longitudinal direction x.

[0157] The material displacement can lead to a change in the size of the printed area 6. The spatial position of sub-areas of the printed area 6 can also be changed. Thus, the information present in the printed sub-area 6 is also changed.

[0158] In particular, a graphic representation, i.e., an appearance, of information present in the printed area 6 can be changed by joining. In particular, the change can be described by a geometric transformation of the representation.

[0159] This may mean that printed information, in particular a graphic symbol, a character, or a photograph, or a part thereof, is geometrically transformed by the material displacement. In particular, scaling, shearing, stretching, or compression of the printed area 6 and thus the graphic representation of the information may occur.

[0160] The geometric transformation generated by joining and the associated material displacement can be a targeted transformation. Thus, depending on the properties of the document layers 2, 3, in particular a material and a geometric shape of the document layer 2, 3, depending on joining parameters, in particular a temperature and a pressure as well as a duration, as well as depending on the relative position of the document layers 2, 3 in the unjoined layer composite 1, a desired geometric transformation of the graphic representation of information present in the printed area 6 can occur.

[0161] The geometric transformation can be performed in such a way that a desired target representation of the information is created after joining. In particular, the representation of the information in the printed area 6 before joining can deviate from the desired target representation. After joining, the representation of the information changed by joining can correspond to the desired target representation or deviate from it by no more than a predetermined amount.

[0162] This is done using the Fig. 4 and Fig. 5 explained in more detail. In Fig. 4 shows a schematic plan view of a layered composite 1, in particular of a first document layer 2, before joining. This schematically shows the printed area 6, in which a photograph 7 is printed on the first document layer 2. The photograph 7 is printed in a distorted manner. Not shown is the further document layer 3 (see e.g. Fig. 1), which is arranged under the printed area 6 or under a partial area of ​​the printed area 6.

[0163] In other words, the detectable, in particular visually detectable, representation of the photographic image of the photographic image 7 deviates from a target representation. For example, in the distorted representation of the photographic image 7, a distance A between the eyes of the face depicted by the photographic image 7 may lie outside a predetermined range of permissible distances.

[0164] By joining, especially lamination, the Fig. 4 shown layer composite 1 of the Fig. 5 can be produced, wherein again a schematic plan view of the layer composite 1, in particular the first document layer 2, is shown. Here, it is shown that a rectified representation, i.e. a target representation, of the photograph 7 is now present in the printed area 6. The joining and the associated material displacement / displacement result in a geometric transformation of at least part of the printed area 6 and in particular of the photograph 7 printed in this part. The transformed distance B between the eyes of the face now lies within a range of permissible distances.

[0165] In particular, the first document layer 2 and the further document layer 3 are designed in such a way, and the arrangement of the first document layer 2 relative to the further document layer 3 is selected prior to joining in such a way that joining results in a desired geometric transformation of the graphic representation of information, in this case the photograph 7. In particular, the geometric transformation can be carried out in such a way that a target representation of the information is created, in particular from a representation that deviates from this target representation.

[0166] Fig. 6 shows a schematic plan view of a joined layered composite 1 according to a further embodiment. This shows a partial region 8 which has a lower density than a region of the layered composite 1 outside the partial region 8. This partial region 8 can be detected optically, and in particular also visually, particularly with transmitted light illumination. It is shown here that the partial region 8 has an oval geometric shape. The partial region 8 can be a partial region of the joined layered composite 1 which corresponds to the thickened region 14 of the unjoined layered composite 1, which is encompassed by this thickened region 14, or which encompasses the thickened region 14.

[0167] Thus, by providing a thickened partial area 14 of the unjoined layer composite through joining, a partial area with a modified density can also be provided. This can also be used for document verification.

[0168] In Fig. Figure 7 shows a schematic flow diagram of a method according to the invention. In a first method step S1, a first and a further document layer 2, 3 (see Fig. 1). In a second method step S2, the further document layer 3 is arranged above or below the first document layer 2 in a desired arrangement relative to the first document layer 2. In this case, the first and / or the further document layer 2, 3 can be positioned. In particular, the document layers 2, 3 can be arranged relative to one another such that the unjoined layer composite 1 is thickened in a predetermined region 14, i.e. has the thickened region 14. In particular, the unjoined layer composite 1 can contain or have information in the thickened region 14.

[0169] In a third step S3, the first and the further document layers 2, 3 are joined. For this purpose, predetermined joining parameters, such as a predetermined temperature, a predetermined pressure, and a predetermined joining time, can be set.

[0170] In Fig. Figure 8 shows a further schematic flow diagram of a method according to the invention.

[0171] The process comprises a determination phase BP and a production phase HP.

[0172] In a first method step S1, a first and a further document layer 2, 3 (see Fig. 1). Furthermore, in the first method step S1, a detectable information according to a desired target representation is applied or introduced onto or into the first document layer 2. In a second step S2, as previously described with respect to the Fig. 7, the further document layer 3 is arranged relative to the first document layer 2. In a third step S3, as previously explained with respect to the Fig. 7, a joining of the first and further document layers 2, 3 is carried out.

[0173] In a fourth method step S4, a graphic representation of information, for example a photograph 7 (see Fig. 5). Furthermore, a geometric transformation, in particular at least one transformation parameter of a geometric transformation, is determined, wherein the geometric transformation describes the transformation with which the representation of the information present in or on the first document layer 2 before joining can be transformed into a representation of the information after joining. This transformation can also be referred to as a forward transformation.

[0174] In a fifth step S5, an inverse transformation, which can also be called a back transformation, is determined.

[0175] The first five steps S1...S5 are steps of the determination phase BP. The first five method steps S1 to S5 can thus be performed before the inventive method for producing a document in order to determine the arrangement of a representation of information on or in the first document layer 2.

[0176] The sixth, seventh and eighth steps S6, S7, S8 are steps of the manufacturing phase HP and correspond respectively to the first step S1, the second step S2 and the third step S3, which are described in Fig. 7. However, in the sixth step S6, the first document layer 2 is provided with a target representation of the information transformed according to the inverse transformation. This representation is then transformed back into the target representation by joining in the eighth step S8.

[0177] Fig. Figure 9 shows a schematic block diagram of an apparatus 9 according to the invention for producing a document. The apparatus 9 comprises a first device 10 for positioning a first document layer 2 (see Fig. 1) and a further device for positioning another document layer 3 (see Fig. 1). Here, the first positioning device 10 is designed as a conveyor belt or comprises such a conveyor belt. Furthermore, the device 9 according to the invention comprises a joining device 12, in particular a laminating device. By means of the Fig. A method according to the invention can be carried out using the device shown in Figure 9. In Fig. 9 further shows that the device 9 can comprise a device 13 for applying information in a desired representation on or in the first and / or further document layer 2, 3, for example a printing device. List of reference symbols 1 layer composite 2 first document situation 3 further documents 4 Top 5 Bottom 6 printed area 7 Photograph 8 sub-area 9 Device 10 Conveyor belt 11 Direction for positioning 12 Joining device 13 Facility for providing information 14 thickened area x Longitudinal direction y lateral direction z Vertical direction S1 first step S2 second step S3 third step S4 fourth step S5 fifth step S6 sixth step S7 seventh step S8 eighth step BP determination phase HP manufacturing phase D Thickness of the joined layer composite D1 Thickness of the first document layer D2 Thickness of the further document layer D2' Thickness of the further document layer

Claims

[1] A method for producing a document, wherein a first document layer (2) and at least one further document layer (3) are provided, wherein the at least one further document layer (3) is arranged above or below the first document layer (2), wherein the document layers (2, 3) are arranged relative to one another in such a way that an unjoined layer composite (1) provided from the first and the further document layer (2, 3) has at least one thickened or thinned partial region (14), wherein the layer composite (1) is joined, wherein the first document layer (2) and the at least one further document layer (3) consist of a laminatable material, wherein the joining is carried out by lamination, characterized byin that the first document layer (2) has at least one printed area (6), wherein the document layers (2, 3) in the unjoined layer composite (2) are arranged relative to one another in such a way that the thickened or thinned partial area (14) comprises at least a partial area of ​​the printed area (6). [2] Method according to claim 1, characterized by that a maximum width of the further document layer (3) is smaller than a maximum width of the first document layer (2) and / or a maximum length (L2) of the further document layer (3) is smaller than a maximum length (L1) of the first document layer (2). [3] Method according to one of the preceding claims, characterized by that the further document layer (3) has a rectangular, circular or oval edge. [4] Method according to one of the preceding claims, characterized by that a photograph or part thereof is printed in the printed area (6). [5] Method according to one of the preceding claims, characterized by that the document layers (2, 3) in the unjoined layer composite (1) are arranged relative to one another in such a way that at least a partial region of the layer composite (1) is deformed by the joining in such a way that information in or on the unjoined layer composite (1) is changed. [6] Method according to claim 5, characterized by that the change in information occurs through a geometric transformation of at least a partial area of ​​the layer composite. [7] Method according to claim 5 or 6, characterized by that information in or on the unjoined layer composite (1), which is different from a target information, is changed into the target information by joining. [8] Method according to one of the preceding claims, characterized by that the layer composite (1) has a changing density after joining. [9] Device for producing a document, wherein the device (9) comprises a first device (10) for positioning a first document layer (2) and / or at least one further device (11) for positioning a further document layer (3), wherein the device (9) further comprises at least one joining device (12), wherein the at least one further document layer (3) can be arranged above or below the first document layer (2), wherein the document layers (2, 3) can be arranged relative to one another in such a way that an unjoined layer composite (1), which is provided from the first and the further document layer (2, 3), has at least one thickened or thinned partial region (14), wherein a joining of the layer composite (1) is possible, wherein the first document layer (2) and the at least one further document layer (3) consist of a laminatable material, wherein the joining is carried out by lamination, characterized by , that the first document layer (2) has at least one printed area (6), wherein the document layers (2, 3) in the unjoined layer composite (2) are arranged relative to one another in such a way that the thickened or thinned partial area (14) comprises at least a partial area of ​​the printed area (6). [10] Device according to claim 9, characterized by that the device (9) comprises at least one device for arranging detectable information in or on the first document layer (2) and / or the further document layer (3). [11] Device according to claim 9 or 10, characterized by that the device (9) comprises at least one computing device for calculating an arrangement of the detectable information on or in the first document layer (2) and / or further document layer (3) in such a way that a target representation of the information is generated by the joining. [12] Document produced by a method according to one of claims 1 to 8, wherein the document has a changing density and / or transformed detectable information by joining a first and at least one further document layer (2, 3).

Images