AU2011276149B2

AU2011276149B2 - Transparent ink-accepting layer

Info

Publication number: AU2011276149B2
Application number: AU2011276149A
Authority: AU
Inventors: Markus Krombholz; Katharina Kugele; Ralf Liebler; Patrick Renner; Rudolf Seidler
Original assignee: Giesecke and Devrient GmbH
Current assignee: Giesecke and Devrient GmbH
Priority date: 2010-07-05
Filing date: 2011-07-01
Publication date: 2014-04-24
Anticipated expiration: 2031-07-01
Also published as: WO2012003947A1; MX2013000033A; EP2590822B1; EP2590822B2; DE102010026071A1; AU2011276149A1; EP2590822A1

Abstract

The invention relates to a security element (2) for the production of valuable documents, comprising at least one transparent ink-accepting layer (5), which is arranged above a first surface of a substrate (1) over the entire area or in at least one sub-region. An opaque ink-accepting layer (9) is applied to a sub-region.

Description

Transparent ink-receiving layer [0001] This invention relates to a security element for manufacturing value documents and to a value document comprising such a security element. [0002] Value documents for the purposes of the present invention are for example bank notes, shares, bonds, deeds, vouchers, checks, lottery tickets, high-value admission tickets, passports, identity cards, credit cards and other planar objects of value. Such planar objects of value can for example also be packages for products that are of high value, where applicable. The term "value document" also comprises for the purposes of the present invention all precursors of finished value documents, which are for example not yet fit for circulation, such as, inter alia, security paper, foil or foil composites. Such a value document can also be only a part within an object of value. [0003] Such value documents are provided for design reasons or for security reasons with security elements which, solely through their presence or their design, permit a check of the authenticity of the value documents and at the same time serve as protection from unauthorized reproduction. A security element for the purposes of the present invention can be e.g. a window or transparent window which is formed e.g. by a transparent foil, a security thread, a feature produced by printing technology such as e.g. a microprint, a foil strip, a patch or a label. A security element, in particular a security element in the form of a security thread or a foil strip, can be configured as an optically variable security element, an optically variable security element being understood for the purposes of the present invention as an optical element whose visual impression produced on a viewer depends on the viewing direction, that is, on the viewer's angle of view of the optical element and, where applicable, also on the direction of incidence of an illumination light beam. Examples of such optically variable security elements are diffractive structures which produce a viewing angle dependent visual impression in particular through reconstruction of optically perceptible patterns, such as for example embossed or volume holograms and other Kinegrams, such as achromatic matt structures. A further example of such optically variable elements is optical elements showing a so-called color-shift effect, such as for -2 example single- or multi-ply thin-film interference layers or liquid-crystal layers, which can respectively be present as a continuous layer or in pigment form (so-called effect pigments such as for example Iriodins). Further examples are lens or micromirror structures within an optically variable security element. Such optical elements have in common that they are usually constructed on the basis of a polymer layer, e.g. a plastic foil, or at least comprise a polymer layer as a cover layer or protective layer. For the purposes of the present invention, such elements are designated in a general way as security elements. In the specific case that the optical element is constructed on the basis of a plastic foil, the element can be designated as an optical foil element. [0004] To increase the forgery-prooffiess, that is, make an imitation more difficult, to facilitate a check of the authenticity or as an additional design element, it is desirable to overprint such security elements, or value documents comprising such security elements, with a further imprint in addition to an imprint already applied, where applicable. However, the ink reception is normally unsatisfactory when such security elements are overprinted. Hence, it is known to provide on such security elements print- or ink-receiving layers (hereinafter designated as ink-receiving layers for simplicity's sake). However, the ink-receiving layers suitable for such security elements are opaque, or at least have an unwanted hazing effect, at the necessary layer thicknesses or as a result of fillers. This has an adverse effect on the visual perceptibility or the machine detectability of the security element. For example, it is then no longer possible to have a good, undisturbed view through a window. When the security element is an optically variable element, its optically variable effect can be impaired or completely prevented. [0005] One counter-measure would be to provide the ink-receiving layer with a reduced layer thickness or with a filler content, so that the opacity and/or the hazing effect of the ink-receiving layer is reduced, to thereby guarantee an improved perceptibility of a security element. This has the disadvantage, however, of worsening the adhesion and drying of the printing ink of the further imprint to be applied. When - 3 there is the requirement of a good ink reception, a more or less strongly pronounced hazing above the security element must be accepted. When there is instead the requirement to manufacture a clear transparent window for example, a satisfactory ink reception of the printing ink of the further imprint on the window has hitherto not been 5 possible. [0006] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general 10 knowledge in the field relevant to the present disclosure as it existed before the priority date of each claim of this application. [0007] Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated 15 element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. [0008] A first aspect of the invention relates to a value document comprising a substrate and a security element which comprises at least a transparent ink-receiving 20 layer which is arranged above a first surface of the security element over the full area or in at least a partial region and which is arranged in or on the substrate such that the first surface of the security element forms a common surface with a first surface of the substrate, wherein the transparent ink-receiving layer is arranged above the common surface over the full area or at least in a first partial region of the common surface and 25 wherein above the common surface an opaque ink-receiving layer is arranged in a partial region of the common surface, which region does not lie above the security element upon viewing of the value document in incident light. [0009] The transparent ink-receiving layer can comprise a filler which is 30 preferably chosen from the group consisting of boehmite, pseudoboehmite, zeolite, -4 A1 2 0 3 and silica gel, and a binder, preferably polyvinyl alcohol. The filler-to-binder ratio preferably lies in the range of 6:1 to 30:1. [0010] The security element can be configured e.g. as a window, security thread, 5 foil strip, as a feature produced by printing technology, patch or label. [0011] In the value document, a transparent layer, preferably a plastic foil, can be arranged between the common surface and the transparent ink-receiving layer. 10 [0012] The next paragraph is [0014] [00141 The value document according to the invention can be characterized in that above the common surface an opaque ink-receiving layer is arranged in at least a second partial region of the common surface, which region does not lie above, i.e. lies 15 outside, the security element upon viewing of the value document in incident light, has a first, preferably unvarying layer thickness there, and has a gap or a reduced layer thickness compared with the first layer thickness in a third partial region of the common surface, which region lies above the security element upon viewing of the value document in incident light. The layer thickness of the opaque ink-receiving layer 20 within the third partial region and/or in a fourth partial region of the common surface, which region lies between the second and third partial regions, can preferably have a course decreasing in a staircase shape or steplessly, preferably with a constant gradient, starting out from the first layer thickness in the second partial region, the layer thickness of the opaque ink-receiving layer decreasing down to zero or approximately 25 zero in the third and/or fourth partial region and particularly preferably amounting to zero in the entire third partial region. The fourth partial region preferably borders directly on the second partial region and the third partial region and completely surrounds the third partial region. 30 [0015] The transparent ink-receiving layer can preferably be arranged below or above the opaque ink-receiving layer within the second, third and, where applicable, -5 fourth partial regions and have an unvarying layer thickness there or have an elevated layer thickness compared with the second partial region in the third and, where applicable, fourth partial regions, preferably such that the sum of the layer thicknesses of transparent ink-receiving layer and opaque ink-receiving layer in the second, third and, where applicable, fourth partial regions is unvarying. [0016] The transparent ink-receiving layer can preferably be arranged below or above the opaque ink-receiving layer only within the third and, where applicable, fourth partial regions, and the layer thickness of the transparent ink-receiving layer can preferably have a course increasing in a staircase shape or steplessly, preferably with a constant gradient, starting out from a layer thickness of zero in the second partial region, such that the sum of the layer thicknesses of transparent ink-receiving layer and opaque ink-receiving layer in the second, third and, where applicable, fourth partial regions is unvarying. [00171 The transparent ink-receiving layer can have a first configuration in a first subregion of the transparent ink-receiving layer and a second configuration in at least a second subregion of the transparent ink-receiving layer, such that the two subregions produce an optically identical impression on a viewer at least upon viewing from a predetermined direction, preferably upon viewing from all directions, the two subregions differing in a technical property, in particular in their ink-receiving behavior or their embossing behavior. [0018] The opaque ink-receiving layer can have a first configuration in a first subregion of the opaque ink-receiving layer and a second configuration in at least a second subregion of the opaque ink-receiving layer, such that the two subregions produce an optically identical impression on a viewer at least upon viewing from a predetermined direction, preferably upon viewing from all directions, the two subregions differing in a technical property, in particular in their ink-receiving behavior or their embossing behavior.

-6 [00191 The subregions of the transparent ink-receiving layer and/or the subregions of the opaque ink-receiving layer can form an information item recognizable to a viewer. 10020] This paragraph has been left blank [0021] The security element according to the invention, e.g. an optical foil element, for the manufacture of value documents comprises at least a transparent ink-receiving layer which is arranged above a first surface of the security element over the full area or in at least a first partial region of the security element. 10022] Ink-receiving layers have the function of guaranteeing the ink reception, that is, the absorption, of the printing ink of a further imprint or of certain ingredients of such printing inks, such as oils, and thus the adhesion and drying of the printing ink of the further imprint. For the purposes of the present invention, the term "ink-receiving layer" is also understood to include layers promoting an improved adhesion to a surface, in particular to a polymer surface, plastic surface or foil surface. The ink-receiving layer can be constructed in single layer fashion or multilayer fashion, that is, from several partial layers, the individual layers being respectively homogeneous. For example, a first partial layer of the ink-receiving layer arranged directly on the surface -7 of the security element, where applicable, mainly promotes an elevated adhesion of a further partial layer of the ink-receiving layer to the security element, while the further partial layer mainly guarantees the ink receptivity of the printing ink of a further imprint. The first partial layer arranged directly on the surface of the security element and having an adhesiveness is also designated as a primer layer or adhesive layer. [0023] According to the invention, the transparent ink-receiving layer is arranged above a first surface of the security element, that is, the transparent ink-receiving layer is e.g. either applied directly to a foil or polymer layer or plastic layer of the security element or is separated therefrom by one or several further, preferably transparent intermediate layers. Upon the printing of the security element with a further imprint, the transparent ink-receiving layer advantageously forms the uppermost layer and thus ensures the ink reception, the adhesion and the drying of the printing ink of the further imprint. The further imprint can be applied using an offset process, a gravure printing process or another suitable printing method. It may involve a background print. [0024] The employment, according to the invention, of a transparent ink-receiving layer makes possible an unimpaired perception of the security element at least before the applying of a further imprint. In particular, there arises no impairment of the perceptibility through a matting or hazing. When the security element involves a simple window or transparent window which is e.g. formed on the basis of a transparent foil, the employment of the transparent ink-receiving layer further makes possible a clear view through the window. When the security element consists of an optically variable security element, the transparent ink-receiving layer permits a perception of an unimpaired optically variable effect. [0025] The transparent ink-receiving layer according to the invention comprises at least a filler and a binder. [0026] As a filler there is preferably employed boehmite, pseudoboehmite, zeolite, A1 2 0 3 or silica gel or a mixture of these substances. With regard to the transparency of the transparent ink-receiving layer, these fillers preferably have a particle size in a -8 range of I nm to 1 stm, the range of 5 nm to 200 nm being particularly preferred. The employment of boehmite or pseudoboehmite is preferred. Boehmite is understood according to "Roempp Lexikon der Chemie", 10th edition, Georg Thieme Verlag, 1996, to be the rhombic crystalline metahydroxide y-AlO(OH), which is obtainable for example from crystalline Al(OH) 3 by heating at 150'C in a sealed tube for 14 days with elimination of water. Pseudoboehmite is an agglomerate from aluminum oxide hydroxide having the formula A1 2 0 3 * n H20 (n = 1 to 1.5). [0027] As binders there are employed for example polyvinyl alcohol, modified polyvinyl alcohol, polyurethane dispersions, acrylate dispersions, as well as derivatives or mixtures of the same. Preferably, the filler-to-binder ratio lies between 6:1 and 30:1, the stated ratio referring to the mass. Thus, the transparent ink-receiving layer comprises considerably more filler than binder. The filler-to-binder ratio can amount to for example 6:1, 8:1, 10:1, 12:1, 15:1, 20:1, 25:1 or 30:1, whereby each of the stated ratios can represent a lower or upper limit of the above-mentioned range. [0028] Besides the stated filler and binder, the ink-receiving layer preferably comprises a cross-linker, in particular from the family of isocyanate, aziridine, carbodiimide or glycidic ether. Further, the transparent ink-receiving layer can comprise further additives such as deaerators or monoprotic acids. [0029] A thus constructed ink-receiving layer is characterized by a good adhesion to plastic layers, in particular plastic foils, and further ensures a good ink receptivity of the printing ink to be applied for the further imprint as well as its drying and adhesion. Hence, this formulation can also be employed as the starting point for developing non transparent ink-receiving layers. For this purpose there are added to the formulation of the ink-receiving layer further additives, such as for example pigments, which produce the desired property. These may be for example pigments such as TiO 2 , BaSO 4 , CaCO 3 , silicic acids, or polymer-based hollow-sphere pigments such as e.g. "ROPAQUE" from the company Rohm & Haas, or also effect pigments producing a pearl luster or a metallic luster, interference pigments, liquid-crystal pigments, -9 thermochromic or magnetic pigments, or pigments producing a phosphorescence or fluorescence or having an antistatic effect. When such an ink-receiving layer has for example a high opacity due to its additives, it is advisable to realize a desired basic color of the security element or of a substrate via the ink-receiving layer, where applicable. [0030] The adhesion of the ink-receiving layer according to the invention to plastic layers, in particular plastic foils, can be improved by means of a primer layer serving as an adhesion promoter. [0031] In a preferred configuration of the security element according to the invention, the element is configured as a window or transparent window, feature produced by printing technology, security thread, foil strip, patch or label, and the transparent ink-receiving layer is applied over the full area. The security element further preferably comprises a polymer layer, e.g. a plastic foil on which the transparent ink-receiving layer is applied. Such a security element can be produced directly on a value document to be protected, or be prepared on a separate carrier as a transfer element. Such a separate carrier preferably has a plastic or polymer material and can be, or have, for example a foil material, in particular a transfer material. For the foil material there come into consideration plastics such as PET (polyethylene terephthalate), PBT (polybutylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PA (polyamide) and PE (polyethylene). This foil material can further be stretched uniaxially or biaxially. [0032] The fastening of the security element on a value document to be protected is effected here using an adhesive layer, there preferably being employed therefor a hot melt adhesive. After the transfer of the security element to a value document to be protected, the carrier material is stripped again, where applicable, so that the security element remains on the value document to be protected. The transparent ink-receiving layer serves here as a separation layer or release layer.

- 10 [00331 On known security elements, in particular on transfer elements, there is frequently employed a transparent UV lacquer as a cover layer and protective layer. In the preferred configuration, this UV lacquer layer is either covered with the transparent ink-receiving layer, or replaced by the transparent ink-receiving layer. [0034] The transparent ink-receiving layer forms the uppermost layer of the security element upon the printing of the foil strip or transfer element with the further imprint, thereby increasing the ink receptivity for the printing ink of the further imprint, because the transparent ink-receiving layer has an improved printing-ink receptivity compared with the known transparent UV lacquer. [0035] In a preferred configuration, the security element can be configured as a patch or label and have for example a planar form with comparable length dimensions in all directions or have an elongate form for example in the form of a strip, as is the case with security threads or foil strips, for example so-called LEAD strips. When such a security element is configured as a transfer element with a foil that is transparent, where applicable, as a carrier, it is also designated as a foil element, foil patch or foil strip. [0036] In a preferred configuration of the invention, a value document comprises a substrate as well as a security element according to the invention which is arranged on the substrate of the value document such that the first surface of the security element forms a common surface with a first surface of the substrate. The transparent ink receiving layer here is arranged above the common surface either over the full area or at least in a first partial region of the common surface. The transparent ink-receiving layer can thus also be arranged in a region outside the security element. The formulation "outside the security element" is intended to mean that the transparent ink receiving layer is not arranged above the security element upon viewing of the value document in incident light. [0037] As the substrate of the value document there can be employed single- or multi-ply substrates. In the case of single-ply substrates, any kind of paper or paper- - 11 like material comes into consideration, in particular cotton vellum paper. There can also be used paper containing a certain content x of a polymer material in the range of 0 to 100 wt.%. Further, there can be employed as the substrate a plastic layer, for example a plastic foil, or a foil composite. Such a foil can additionally be stretched uniaxially or biaxially. Such stretching of the foil results, inter alia, in it acquiring polarizing properties, which can be utilized as a security feature in the value document. [0038] As a multi-ply substrate there can be employed a multi-ply composite having for example a layer of paper or a paper-like material. On this layer there is laminated for example from both sides a transparent plastic or polymer layer, thereby giving such a multi-ply composite an exceptionally great stability and durability. Here, security papers with plastic- or polymer-coated paper layers are employed for manufacturing foil-composite bank notes. Conversely, the multi-ply composite can also have a central layer of a plastic or polymer material which is coated on both sides with a respective ply of paper or paper-like material. As a multi-ply substrate material there can also be used a multilayer, paper-free composite material. [0039] The security element can be arranged on the surface of the substrate. However, it can also be arranged within the substrate and pass to the surface of the substrate for example only in certain regions, as is the case with security threads such as windowed or pendulating security threads. The security element can also fill a gap in the substrate, as is the case with windows, in particular transparent windows. Also, in the case of a composite consisting of several layers, such as a foil-composite bank note, the security element can also be arranged below a transparent layer, e.g. a plastic foil, or be embedded within the transparent layer. [0040] A security element configured as a transfer element and having a full-area transparent ink-receiving layer is particularly suited for application on a value document whose substrate surface consists of paper or a paper-like material, in particular when the transparent ink-receiving layer is realized such that it has the same, or a similar, ink receptivity as the paper or paper-like substrate surface of the value -12 document, because there can thus be realized a value document having a security element which has a high ink receptivity on its entire surface without necessitating any further coating steps. [00411 The transparent ink-receiving layer can be arranged directly on the common surface of security element and substrate. In a preferred configuration, however, a further transparent layer, for example a plastic foil, in particular a PET foil or polyester foil, is arranged between the common surface and the transparent ink-receiving layer. The transparent layer forms here for example a cover layer or protective layer for the security element and the substrate. The transparent ink-receiving layer then ensures the printability with the printing ink of a further imprint. Preferably, the further transparent layer is arranged directly on the common surface, and/or the transparent ink-receiving layer is arranged directly on the further transparent layer, e.g. a plastic foil. {0042] In a preferred configuration of the value document, there is arranged above the common surface additionally an opaque ink-receiving layer besides the transparent ink-receiving layer. In a second partial region of the common surface, which region lies outside the security element, that is, not above the security element upon viewing of the value document in incident light, the opaque ink-receiving layer has a first, preferably unvarying layer thickness. A third partial region of the common surface is located above the security element and is preferably defined by the extension of the security element. In this third partial region, the opaque ink-receiving layer has a gap, that is, a layer thickness of zero or at least a reduced layer thickness compared with the first layer thickness. Therefore, the security element is covered completely only by the transparent ink-receiving layer. The opaque ink-receiving layer is arranged only in regions outside the security element. [0043] Such a configuration permits an arrangement of an opaque ink-receiving layer on the value document without impairing the perceptibility of the security element, while simultaneously guaranteeing a good printability of the value document also above the security element.

- 13 [0044] In the edge regions of the opaque ink-receiving layer, for example where the opaque ink-receiving layer borders directly on the transparent ink-receiving layer, however, there can occur unwanted shiny edges (sticky-tape effect). Such shiny edges stand in the way of a desired uniform appearance of the surface of the value document. In a preferred configuration, the layer thickness of the opaque ink-receiving layer within the third partial region and/or in a fourth partial region hence decreases in a staircase shape or steplessly, preferably down to zero or approximately zero, starting out from the first layer thickness of the opaque ink-receiving layer in the second partial region. This decreasing course preferably shows a constant gradient. The fourth partial region of the common surface lies between the second and the third partial regions and preferably borders directly on the third partial region and surrounds it completely. In the simplest case, the third partial region defines the region of the security element, by which the fourth partial region defines an edge region of the security element which lies outside the security element and directly surrounds it. The fourth partial region preferably has a constant width. The layer thickness of the opaque ink-receiving layer decreases in the third and/or fourth partial region down to zero or approximately zero. Particularly preferably, the layer thickness of the opaque ink-receiving layer in the entire third partial region amounts to zero, and the layer thickness of the opaque ink receiving layer decreases in the fourth partial region from the first layer thickness to zero starting out from the edge region toward the second partial region up to the edge region toward the third partial region. [0045] Through such a gradual course of the layer thickness of the opaque ink receiving layer, the edge region of the opaque ink-receiving layer is only slightly recognizable and spurious shiny edges for example at the transition region between opaque and transparent ink-receiving layers are avoided. [0046] In a further preferred configuration, the transparent ink-receiving layer is arranged within the second, third and, where applicable, fourth partial regions below or above the opaque ink-receiving layer, has an unvarying layer thickness there, and is preferably configured as a contiguous layer. In the simplest case, the transparent ink- - 14 receiving layer is for this purpose applied on the value document with unvarying layer thickness. Alternatively, the transparent ink-receiving layer can have in the third and, where applicable, fourth partial regions an elevated layer thickness compared with the second partial region, in order to completely or at least partly compensate the reduced layer thickness of the opaque ink-receiving layer in this region. Particularly preferably, the layer thickness of the transparent ink-receiving layer is configured here such that the sum of the layer thicknesses of transparent and opaque ink-receiving layers in the second, third and, where applicable, fourth partial regions is unvarying, preferably over the full area on the entire surface of the value document. In this case, the layer thickness of the transparent ink-receiving layer in the third and/or fourth partial region has a course increasing in a staircase shape or steplessly in the direction of the third partial region, said course corresponding to the opaque ink-receiving layer, preferably with a constant gradient, starting out from the second partial region. Particularly preferably, the transparent ink-receiving layer has a constant layer thickness in the third partial region and shows a different layer thickness only in the fourth partial region. [0047] Through such configurations of opaque and transparent ink-receiving layers on the value document there is created a completely planar common surface of opaque and transparent ink-receiving layers. [0048] In a further preferred configuration, the transparent ink-receiving layer is arranged only within the third and, where applicable, fourth partial regions, that is, the layer thickness of the transparent ink-receiving layer in the second partial region amounts to zero. Within the third and/or, where applicable, fourth partial region the layer thickness of the transparent ink-receiving layer again shows a course increasing in a staircase shape or steplessly in the direction of the third partial region, preferably with a constant gradient, starting out from the layer thickness zero at the edge region toward the second partial region, so that the sum of the layer thicknesses of transparent and opaque ink-receiving layers in the second, third and, where applicable, fourth partial regions is unvarying, preferably over the full area on the entire value document.

- 15 When the layer thickness of the opaque ink-receiving layer in the third partial region amounts to the value zero, the layer thickness of the ink-receiving layer in the third partial region is unvarying and equal to the layer thickness of the ink-receiving layer in the second partial region. [0049] Through such configurations of opaque and transparent ink-receiving layers on the value document there is created a completely planar common surface of opaque and transparent ink-receiving layers. [0050] In a further preferred configuration of the value document, the transparent ink-receiving layer has a first and a second subregion, the transparent ink-receiving layer possessing in the first and second subregions a first and a second configuration which are mutually different. The region in which the transparent ink-receiving layer is applied is thus subdivided into at least two subregions which preferably border on each other. The configuration in the two subregions is such that the two subregions produce an optically identical impression on a viewer at least upon viewing from a predetermined viewing direction and preferably upon viewing from all viewing directions, while the two subregions differ in a technical property. This can be for example the ink-receiving behavior with respect to the further imprint to be applied or the behavior upon embossing of the value document and/or of the security element. [0051] Likewise, the opaque ink-receiving layer can alternatively or additionally have a first and a second subregion, the opaque ink-receiving layer possessing in the first and second subregions a first and a second configuration which are mutually different. The region in which the opaque ink-receiving layer is applied is thus subdivided into at least two subregions which preferably border on each other. The configuration in the two subregions is such that the two subregions produce an optically identical impression on a viewer at least upon viewing from a predetermined viewing direction and preferably upon viewing from all viewing directions, while the two subregions differ in a technical property. This can be for example the ink-receiving -16 behavior with respect to the further imprint to be applied or the behavior upon embossing of the value document and/or of the security element. [0052] Directly after the applying of the opaque and/or transparent ink-receiving layer, the respective two subregions are indistinguishable to a viewer at least upon viewing from a predetermined viewing direction and preferably upon viewing from all viewing directions. When the respective two subregions differ for example in their ink receiving behavior with respect to the printing ink of the further imprint to be applied, the two subregions are indistinguishable in the unprinted state, as described above. Upon the applying of the printing ink of the further printed image to the respective two subregions of transparent or opaque ink-receiving layer, they become distinguishable to a viewer at least upon viewing from a predetermined direction, preferably upon viewing from all viewing directions, by producing a different optical impression on the viewer, for example a different color brilliance. It is advantageous here when the printing ink of the further printed image is applied to the respective two subregions as a background print over the full area. [0053] Alternatively or additionally, the respective two subregions can also differ in their behavior with respect to an embossing, that is, they have for example a mutually different mechanical stability. 100541 The necessary different configuration of the respective two subregions of opaque and/or transparent ink-receiving layers can be obtained in the case of a multilayer construction by a different layer construction or by different formulations for the ink-receiving layers in the respective subregions. For example, there can be provided in a subregion additional pigments in the ink-receiving layer whose presence is recognizable only upon viewing in a predetermined viewing direction, as is the case for example with effect pigments such as interference pigments or liquid-crystal pigments which show for example a color-shift effect. Alternatively, upon employment of such effect pigments the same formulations can also be employed for the ink receiving layer in both subregions, the orientation of the effect pigments being - 17 configured mutually differently in these subregions. For the different subregions of an opaque ink-receiving layer, different ingredients changing the transmission behavior can also be employed, thereby causing the two subregions of the opaque ink-receiving layer to produce an identical optical impression in incident light but to be mutually distinguishable in transmitted light. [0055] In a further preferred configuration, the respective subregions of opaque and/or transparent ink-receiving layer are arranged such that a recognizable information item results for the viewer when these subregions are mutually distinguishable. The substructure formed by the two respective subregions forms for example a motif or a graphical or alphanumeric character. [00561 In the security element according to the invention as well as the value document according to the invention, the transparent ink-receiving layer can additionally be provided with an overlacquering, through which a matting and/or a lengthening of the life and fitness for circulation can be obtained. A suitable lacquer layer is e.g. a lacquer system consisting of a lower and an upper lacquer layer, which is disclosed e.g. in WO 2004/072378 Al, whose disclosure is also incorporated herein by reference. The lower lacquer layer can be a water-based dispersion lacquer layer which is based e.g. on water-based dispersions of aliphatic polyester polyurethanes or acrylic styrene polyurethanes. The upper lacquer layer is preferably a radiation-curing and/or physically drying lacquer layer. Suitable for a physically drying lacquer layer are water-based dispersions, preferably without polyurethane content, e.g. based on acrylic-styrene. However, the upper lacquer layer can also contain a hybrid lacquer which contains a physically drying as well as a radiation-curing lacquer content. [00571 Further embodiment examples and advantages of the invention will be explained hereinafter by way of example with reference to the accompanying figures. The examples represent preferred embodiments which in no way limit the invention. The shown figures are schematic representations which do not reflect the real - 18 proportions but rather serve to improve the clearness of the different embodiment examples. [0058] Specifically, the figures show: Figure L a a bank note having a security element in plan view; Figure lb a section through the bank note from Figure 1a; Figures 2a to 2f sectional views through further embodiment examples; Figures 3a to 3c plan views of different configurations of partial regions; and Figure 4 a plan view of a further embodiment example of a value document. 100591 In Figures la and lb there is represented as a value document a bank note having a substrate 1. On the substrate 1 the denomination "50" is imprinted. The substrate I of the value document consists in this embodiment example of a paper or a paper-like material and has an accordingly high ink receptivity and good printability for a further imprint to be applied, not represented in Figure la. On the substrate L there is further arranged a security element 2, e.g. an optical foil element, which is a transfer element in the shown embodiment example. The security element 2 comprises an adhesive layer 3 which comprises an activatable adhesive, for example a hot-melt adhesive. Using the adhesive layer 3 the central foil component 4 of the optical foil element 2 is fixed on the surface of substrate 1. To guarantee a good printability of the optical foil element 2 and in particular of the central foil component 4, the optical foil element 2 further comprises a transparent ink-receiving layer 5. Accordingly, the resulting surface of the bank note consists of the transparent ink-receiving layer 5 in the region of the optical foil element 2, and of the surface of the substrate 1 in the remaining region. There is accordingly created a high ink receptivity and thus a good printability on the entire value document over the full area, that is, the ink receptivity - 19 of the substrate is not impaired by the applying of the described optical foil element configured as a transfer element. [0060] In Figure 2a there is represented a second embodiment example of a value document in the form of a bank note. The value document again comprises a substrate 1 which can consist of paper or a paper-like material or also of plastic or a foil. The substrate is typically opaque. In the case of a plastic bank note, however, the substrate is usually a transparent foil. In the substrate 1 there is arranged a first optical foil element in the form of a window 6 (through window) and a second optical foil element in the form of a security thread 7. Window 6 as well as security thread 7 pass to the surface in the substrate 1, by which the common surface of substrate 1, window 6 and security thread 7 generally consists of different materials. To guarantee a uniform ink receptivity for the further imprint to be applied, a transparent ink-receiving layer 5 can be arranged directly on this common surface. The embodiment example represented in Figure 2a, however, is a foil composite bank note in which substrate 1 as well as window 6 and security thread 7 are covered by a plastic layer 8, for example a PET foil. The transparent ink-receiving layer 5 is in this case arranged directly on the plastic layer 8. Further, the bank note represented in Figure 2a can have further layers not represented, such as for example adhesive or primer layers, which for example guarantee a sufficient adhesion of the different layers to each other. The transparent ink-receiving layer 5 thus forms a uniform surface of the value document, thus creating a uniform and high ink receptivity on the entire value document. [00611 The further embodiment example represented in Figure 2b in cross section differs from the embodiment example represented in Figure 2a by an additional opaque ink-receiving layer 9. The transparent ink-receiving layer 5 can be arranged on the value document over the full area, as represented in this embodiment example, or else only in a first partial region above the common surface of substrate 1, window 6 and security thread 7, that is, above the surface of the value document, the transparent ink receiving layer 5 being arranged at least above the optical foil elements, that is, above window 6 and security thread 7. The opaque ink-receiving layer 9 is not applied over - 20 the full area on the surface of the value document. The surface of the value document is divided into respective one or several second partial regions B, third partial regions C and fourth partial regions D. The second partial regions B are completely outside the optical foil elements, that is, they do not overlap with window 6 or security thread 7. In the embodiment example represented in Figure 2b, the third partial regions C correspond to the regions of the optical foil elements, that is, they are arranged above window 6 and security thread 7. In this embodiment example, the third partial regions C possess the dimensions of the optical foil elements, but they can alternatively also cover a greater or a smaller region. The fourth partial regions D are transition regions between the second partial regions B and the third partial regions C and are directly adjacent to the second partial regions B and the third partial regions C. Because the third partial regions C correspond to the regions of the optical elements, the fourth partial regions D form an exterior edge region around the optical foil elements. The fourth partial regions D preferably have a constant width. 100621 In the second partial regions the opaque ink-receiving layer 9 is applied with a first, unvarying layer thickness. In the third partial regions C the layer thickness of the opaque ink-receiving layer 9 amounts to zero, that is, in the third partial regions C no opaque ink-receiving layer 9 is applied. Thus, the optical perceptibility of the optical foil elements is not impaired by the presence of the opaque ink-receiving layer 9. In the fourth partial regions D the layer thickness of the opaque ink-receiving layer 9 shows a course decreasing toward the third partial regions C, which course can be stepless, as represented in this embodiment example, or can also be configured in a staircase shape. Through this decreasing course of the layer thickness of the opaque ink-receiving layer 9 in the fourth partial regions D there is created a transition region of the opaque ink-receiving layer 9, which for example prevents the occurrence of so called shiny edges and the occurrence of the so-called sticky-tape effect. [0063] In the embodiment example represented in Figure 2b, the opaque ink receiving layer 9 is arranged above the transparent ink-receiving layer 5. However, it is also possible to arrange the transparent ink-receiving layer 5 above the opaque ink- -21 receiving layer 9, as is represented in the embodiment example represented in Figure 2c. This has the advantage of thereby creating a surface of the value document that is uniform with respect to the ink receptivity. [0064] In the embodiment example represented in Figure 2c, the layer thickness of the transparent ink-receiving layer 5 is unvarying on the entire value document and thus in the second B, third C and fourth D partial regions. In the embodiment example represented in Figure 2d, the layer thickness of the transparent ink-receiving layer 5 in the third partial regions C and fourth partial regions D is elevated in comparison to the layer thickness in the second partial regions B, so that the reduced layer thickness of the opaque ink-receiving layer 9 in these regions is compensated, so that the total layer thickness of opaque 9 and transparent 5 ink-receiving layers is unvarying and there thus results a completely planar surface of the value document. [0065] In the embodiment example represented in Figure 2e, the layer thickness of the transparent ink-receiving layer 5 is zero in the second partial regions B and is only non-zero in the third partial regions C and fourth partial regions D. The transparent ink-receiving layer 5 thus fills the gaps in the opaque ink-receiving layer 9, thereby creating a completely planar surface of the value document in this way as well. [0066] In the embodiment examples represented in Figures 2c, 2d and 2e, the transparent ink-receiving layer 5 is arranged above the opaque ink-receiving layer 9, that is, the transparent ink-receiving layer 5 is applied in a later method step than the opaque ink-receiving layer 9. In the embodiment example represented in Figure 2f, however, the transparent ink-receiving layer 5 is applied to the value document in an earlier method step than the opaque ink-receiving layer 9, by which the transparent ink receiving layer 5 lies below the opaque ink-receiving layer 9. It is possible to provide a completely planar surface of the value document in this case as well. [0067] In a non-represented variant of the embodiment example represented in Figure 2f, the transparent ink-receiving layer 5 is arranged on the value document over the full area and has an elevated layer thickness in the third partial regions C and fourth - 22 partial regions D, such that the total layer thickness of opaque 9 and transparent 5 ink receiving layers is again unvarying. [0068] In Figure 3a there is represented in plan view the window 6 shown in Figures 2a to 2f. It is of circular configuration and the third partial region C is arranged exactly above the window 6, thus itself being of circular configuration. The fourth partial region D forms a ring of constant width around the third partial region C, the fourth partial region D being directly adjacent to the third partial region C. The second partial region B is directly adjacent to the fourth partial region D. Thus, the layer thickness of the opaque ink-receiving layer 9 shows a gradual course in the radial direction starting out from the center of the circular window 6 in a ring region which is directly adjacent to the window 6 outwardly in the radial direction. [0069] The third partial region C can also form a region deviating from the region of the optical foil element, however, as is represented by way of example in Figure 3b, where the third partial region C is a a strip-shaped region in which the circular window 6 comes to lie completely. The fourth partial regions D and second partial regions B form further strip-shaped regions which are directly adjacent. [00701 Such a strip-shaped third partial region C is suited in particular for elongate optical foil elements, such as for example the security thread 7 already represented in Figures 2a to 2f. In the embodiment example represented in Figure 3c, the third partial region C is wider than the security thread 7, the fourth partial regions D again being adjacent to the third partial region C as further strip-shaped regions, and directly adjacent thereto further the second partial regions B. [0071] Thus, the configuration of the third partial regions C, of the fourth partial regions D and of the second partial regions B can be adapted to the application method of the opaque and transparent ink-receiving layers. These can be applied by common printing methods such as gravure printing, screen printing or flexographic printing, but also by coating methods in which the transparent and/or opaque ink-receiving layer is poured or sprayed onto the surface or is applied with rollers. A strip-shaped -23 configuration of the third C, fourth D and second B partial regions as represented in Figures 3b and 3c is suited in particular when the opaque and/or transparent ink receiving layer is applied to the value document using print rollers. [0072] In the embodiment example represented in Figure 4 there is arranged over an optical foil element 2, which can be configured as a transfer element, a transparent ink-receiving layer 5 which has different configurations in the subregions 5a and 5b. Before the overprinting with a further imprint, the subregions 5a and 5b are not recognizable to a viewer. However, the configurations of the transparent ink-receiving layer 5 in the subregions 5a and 5b differ in their ink-receiving behavior. Therefore, the applied further imprint appears for example with different brilliance in the subregions 5a and 5b. Thus there can be created in the transparent ink-receiving layer an additional substructure formed by the subregions 5a and 5b, which becomes recognizable only after overprinting with a further imprint. Alternatively or additionally, the configurations of the transparent ink-receiving layer in the subregions 5a and 5b can also differ in other properties. For example, effect pigments can be provided in one of the two subregions in the transparent ink-receiving layer 5, thereby causing the subregions to be distinguishable only upon viewing from a predetermined viewing direction. Further, the transparent ink-receiving layer can differ in its embossing behavior in the subregions 5a and 5b, thereby causing the different subregions 5a and 5b to become recognizable only after an embossing of the value document. [0073] The subregions 5a and 5b can, in so doing, form a substructure which conveys to the viewer an information item, for example a motif or a graphical or alphanumeric symbol. [0074] Likewise, the opaque ink-receiving layer 9 can also have a subregion 9a in which the opaque ink-receiving layer has a configuration resulting in an ink-receiving behavior different from the remaining region of the opaque ink-receiving layer 9, or resulting in a different embossing behavior. Likewise, effect pigments can also be - 24 provided only in a subregion 9a of the opaque ink-receiving layer, or effect pigments differing in their composition and/or orientation from the effect pigments in the remaining ink-receiving layer. In the case of the opaque ink-receiving layer, the possibility also presents itself of producing in the subregion 9a, through the employment for example of different fillers, a transmitted light behavior differing from the remaining opaque ink-receiving layer 9. The subregion 9a is then not recognizable in incident light, but perceptible in transmitted light. [0075] In the embodiment examples shown in Figures 1 to 4, the invention was described with reference to security elements configured as optical foil elements and formed on the basis of a foil. However, the present invention is not limited to optical foil elements. There might equally well be employed security elements having a polymer layer instead of a plastic foil. Likewise, the security element may be e.g. a feature produced by printing technology, e.g. a microprint.

Claims

1. A value document comprising a substrate and a security element which comprises at least a transparent ink-receiving layer which is arranged above a first surface of the security element over the full area or in at least a partial region and which is arranged in or on the substrate such that the first surface of the security element forms a common surface with a first surface of the substrate, wherein the transparent ink-receiving layer is arranged above the common surface over the full area or at least in a first partial region of the common surface and wherein above the common surface an opaque ink-receiving layer is arranged in a partial region of the common surface, which region does not lie above the security element upon viewing of the value document in incident light.

2. The value document according to claim 1, wherein the transparent ink-receiving layer comprises a filler and a binder.

3. The value document according to claim 2, wherein the filler is chosen from the group consisting boehmite, psuedobeohmite, zeolite, A1 2 0 3 and silica gel.

4. The value document according to claim 2 or 3, wherein the binder is polyvinyl alcohol.

5. The value document according to any one of claims 2 to 4, wherein the filler-to-binder ratio lies in the range of 6:1 to 30:1.

6. The value document according to any one of the preceding claims, wherein the security element is configured as a window, security thread, foil strip, feature produced by printing technology, patch or label.

7. The value document according to any one of the preceding claims, wherein a transparent layer is arranged between the common surface and the ink-receiving layer.

8. The value document according to claim 7, wherein the transparent layer is a plastic foil. - 26

9. The value document according to any one of the preceding claims, wherein above the common surface an opaque ink-receiving layer is arranged in at least a second partial region of the common surface, which region does not lie above the security element upon viewing of the value document in incident light, has a first layer thickness there, and has a gap or a reduced layer thickness compared with the first layer thickness in a third partial region of the common surface, which region lies above the security element upon viewing of the value document in incident light.

10. The value document according to claim 9, wherein the first layer thickness is unvarying.

11. The value document according to claim 9 or 10, wherein the layer thickness of the opaque ink-receiving layer within the third partial region and/or in a fourth partial region of the common surface, which region lies between second and third partial regions, has a course decreasing in a staircase shape or steplessly, starting out from the first layer thickness in the second partial region, the layer thickness of the opaque ink-receiving layer decreasing down to zero or approximately zero in the third and/or fourth partial region.

12. The value document according to claim 11, wherein the course decreases with a constant gradient.

13. The value document according to claim 11 or 12, wherein the layer thickness of the opaque ink-receiving layer decreases down to zero in the entire third partial region.

14. The value document according to any one of claims 9 to 13, wherein the fourth partial region borders directly on the second partial region and the third partial region and completely surrounds the third partial region.

15. The value document according to any one of claims 9 to 14, wherein the transparent ink-receiving layer is arranged below or above the opaque layer within the second, third and, where applicable, fourth partial regions and has an unvarying layer thickness there or has an elevated layer thickness compared with the second partial region in the third and, where applicable, fourth partial regions. -27

16. The value document according to claim 15, wherein the sum of the layer thicknesses of transparent ink-receiving layer and opaque ink-receiving layer in the second, third and, where applicable, fourth partial regions is unvarying.

17. The value document according to any one of claims 9 to 14, wherein the transparent ink-receiving layer is arranged below or above the opaque ink-receiving layer only within the third, and where applicable, fourth partial regions, wherein the layer thickness of the transparent ink-receiving layer has a course increasing in a staircase shape or steplessly starting out from a layer thickness of zero in the second partial region, such that the sum of the layer thicknesses of transparent ink-receiving layer and opaque ink-receiving layer in the second, third and, where applicable, fourth partial regions is unvarying.

18. The value document according to claim 18, wherein the course increases with a constant gradient.

19. The value document according to any one of the preceding claims, wherein the transparent ink-receiving layer has a first configuration in a first subregion of the transparent ink-receiving layer and a second configuration in at least a second subregion of the transparent ink-receiving layer, such that the two subregions produce an optically identical impression on a viewer at least upon viewing from a predetermined direction or upon viewing from all directions, the two subregions differing in a technical property.

20. The value document according to any one of claims 9 to 19, wherein the opaque ink receiving layer has a first configuration in a first subregion of the opaque ink-receiving layer and a second configuration in at least a second subregion of the opaque ink-receiving layer, such that the two subregions produce an optically identical impression on a viewer at least upon viewing from a predetermined direction, preferably upon viewing from all directions, the two subregions differing in a technical property.

21. The value document according to claim 19 or 20, wherein the technical property is ink receiving behavior or embossing behavior. -28

22. The value document according to any one of claims 19 to 21, wherein the subregions of the transparent ink-receiving layer and/or the subregions of the opaque ink-receiving layer form an information item recognizable to a viewer.