Valuable document, valuable document system, manufacturing method and inspection method having a luminescent feature

Abstract

The invention relates to a planar value document (10) having a face area with a longitudinal direction (L) and a transverse direction (Q) and provided with a luminescent feature (12) in the face area. According to the invention it is provided that the luminescent feature (12) comprises a first luminescent marking in a first sub-area (14) and a second luminescent marking in a different second sub-area (16). The first and the second luminescent marking are excitable to luminescence at the same wavelength and luminesce after excitation substantially in the same emission band in the infrared spectral range. The first and the second luminescent marking have spectrally similar infrared emission spectra, i.e. infrared emission spectra with a spectral difference of between 0.5% and 15%. The first and the second sub-area are arranged in the face area so as to overlap one another in a projection in the longitudinal direction (L) and / or in a projection in the transverse direction (Q).

Description

[0001] This invention relates to a valuable document with luminescent features, and more particularly to a planar valuable document, such as a banknote, having planar areas with longitudinal and transverse directions, and having luminescent features disposed in these planar areas. The invention also relates to a valuable document system comprising a plurality of different such valuable documents, a method for manufacturing such a planar valuable document, and a method for inspecting such a planar valuable document.

[0002] To protect valuable documents and to verify or classify their authenticity, it is known to introduce or apply machine-examined, especially optically-examined, security features to or on valuable documents. These features may be, for example, luminescent features or luminescent markings, wherein luminescent features that are normally invisible to the human eye and emit light in the infrared (IR) spectrum are used as concealed security features.

[0003] In authenticity checks or classifications, for example, sensors illuminate a valuable document with excitation light and detect the light emitted by the document in response to detect characteristic properties or feature intensity. The detected properties are then compared with reference values ​​or thresholds to classify the features and thus the valuable document. For example, in an authenticity check, a valuable document could be classified into one of the categories of "genuine" or "suspected forgery."

[0004] It is known that during the manufacture of valuable documents, luminescent features in the form of powdered materials or pigments are added to semi-finished products, such as pulp, masterbatch / polymer melts, or printing colors, varnishes, or color concentrates. The semi-finished products are, for example, pulp, valuable document substrates in sheet or sheet form, printed matter in sheet form, sheets or single sheets, film elements such as blocks, lines, strips or plates, fibers, or printing colors or color concentrates, which are further processed into finished valuable documents. In particular, luminescent feature powders can be added to printing colors and leave an imprint on the valuable document substrate.

[0005] Different combinations of luminescent materials can be used to generate unique codes for different categories of valuable documents.

[0006] To generate unique coding categories that reliably separate different valuable documents under real-world usage conditions, such as on a banknote processing machine, the expected production fluctuations in luminescent characteristics, as well as the expected tolerances of the sensing devices during measurement, must be considered when defining different categories. This significantly limits the number of reliably separable coding categories in practice. This is particularly true in banknote processing, where different banknotes are inspected or sorted on high-speed banknote processing machines. Processing speeds can reach 12 m / s, placing high demands on the reliable separation of different coding categories.

[0007] Based on this, the technical problem to be solved by the present invention is to provide a valuable document of the type described at the beginning, which allows for reliable inspection or classification of valuable documents while providing high anti-counterfeiting security. The present invention also provides a manufacturing method and a method for inspecting such a valuable document.

[0008] This technical problem is solved by the features of the independent claim. The improved design of the present invention is the content of the dependent claim.

[0009] According to the present invention, the luminescent features of this planar valuable document include a first luminescent mark in a first sub-region and a second luminescent mark in different second sub-regions.

[0010] The first and second luminescent markers can be excited to emit light at the same wavelength, hereinafter also referred to as the excitation wavelength, and after excitation, they emit light substantially within the same emission band in the infrared spectral range. The emission band can preferably be an associated wavelength range or wavelength interval near the maximum intensity of the emission spectrum in the infrared spectral range, wherein the intensity is greater than 5% of the maximum intensity of the emission spectrum in the infrared spectral range. If the emission bands overlap by more than 90% of the width of the wider emission band, the emission bands are preferably substantially the same.

[0011] The first and second luminescent markers have similar infrared emission spectra, i.e., infrared emission spectra with a spectral difference between 0.5% and 15%.

[0012] The spectral difference between the emission spectra of the first and second luminescent markers can be given, in particular, as the maximum value of the difference spectral quantity of the two emission spectra, which are respectively normalized to the emission maximum value, within the spectral range formed by or including the emission band.

[0013] Furthermore, the first and second sub-regions are arranged in the surface region to overlap each other in the longitudinal projection and / or the transverse projection.

[0014] In particular, the face region is identical to the valuable file, meaning that the edge of the face region corresponds to the edge of the valuable file.

[0015] In the case of rectangular areas, the vertical direction typically represents the direction of the longer dimension, while the horizontal direction represents the direction perpendicular to the shorter dimension of the area. For square areas, the vertical and horizontal dimensions are the same.

[0016] In particular, valuable documents can be designed to resemble banknotes.

[0017] However, a valuable document can also be a book-shaped document, such as a page from a passport. The first and second sub-regions can, in particular, be located on the same page as a book-shaped document. Portrait or landscape orientation can indicate the longer or shorter dimensions of the page.

[0018] The spectral similarity between the two luminescent markers or their infrared emission spectra ensures that environmental influences and / or variations in the sensors used to detect the emission have the same effect on the measurements of the two luminescent markers and can therefore be well compensated for through difference assessment.

[0019] The minute spectral differences between the two emission spectra also contribute to increased security against counterfeiting of valuable documents, because potential counterfeiters, when analyzing the original valuable document, can only identify a single, seemingly identical emission within the range of measurement accuracy, and at most attempt to mimic that single emission.

[0020] Advantageously, the first and second luminescent markers, or their infrared emission spectra, have a spectral difference of between 1% and 11%, preferably between 2% and 7%.

[0021] Suitably, the first and second luminescent markers can be excited within a wavelength range of 700 to 2500 nm, preferably within a wavelength range of 900 to 2100 nm. Alternatively or additionally, the first and second luminescent markers are selected such that they emit light within a wavelength range of 700 to 2500 nm, preferably 900 to 2100 nm, after excitation. Preferably, the emission wavelength is greater than the excitation wavelength, especially by up to 100 nm.

[0022] These two luminescent markers advantageously exhibit virtually no upconversion and, in particular, emit virtually no light in the visible spectrum after excitation, i.e., less than 1% of their total emission power, for example. Therefore, the luminescence of the luminescent features is imperceptible to the naked eye and constitutes a concealed security feature with a high level of security.

[0023] The first and / or second luminescent markers advantageously comprise organic, organometallic, or inorganic luminescent materials. Advantageous examples of such luminescent materials are doped inorganic pigments containing dopants neodymium and / or ytterbium and / or erbium and / or thulium and / or holmium, or doped with a defined transition metal such as manganese. Furthermore, organometallic composites containing neodymium and / or ytterbium and / or erbium or defined organic color materials are preferred. Suitable inorganic matrices are, for example:

[0024] Oxides, especially trivalent and tetravalent oxides, such as titanium oxide, aluminum oxide, iron oxide, boron oxide, yttrium oxide, cerium oxide, zirconium oxide, and bismuth oxide; and more complex oxides, such as garnets, including yttrium iron garnet, yttrium aluminum garnet, and gadolinium gallium garnet; perovskites, including yttrium aluminum perovskite and lanthanum gallium perovskite; spinels, including zinc aluminum spinel, magnesium aluminum spinel, and manganese iron spinel; or mixed oxides, such as ITO (indium tin oxide); halide oxides and chalcogenides, especially oxychlorides, such as yttrium oxychloride and lanthanum oxychloride; and oxysulfides, such as yttrium oxysulfide and gadolinium oxysulfide; sulfides and other chalcogenides. Examples include zinc sulfide, cadmium sulfide, zinc selenide, and cadmium selenide; sulfates, especially barium sulfate and strontium sulfate; phosphates, especially barium phosphate, strontium phosphate, calcium phosphate, yttrium phosphate, and lanthanum phosphate, as well as more complex phosphate-based compounds, such as apatite, including calcium hydroxyapatite, calcium fluorapatite, and calcium chloroapatite; or fluorapatite, including, for example, calcium fluorapatite and calcium chlorofluorapatite; silicates and aluminosilicates, especially zeolites, such as zeolite A and zeolite Y; zeolite-related compounds, such as sodalite; feldspars, such as alkali feldspar and plagioclase; and other inorganic compounds, such as vanadates, germanates, arsenates, niobates, and tantalates.

[0025] In a favorable design, it is specified that the first and second luminescent markers each contain only a single luminescent material.

[0026] Alternatively, the first and / or second luminescent markers may also contain multiple luminescent materials. The latter allows for a very precise difference between the two luminescent markers with ease of manufacturing. In particular, it can be specified that the first and second luminescent markers contain a common luminescent material, and at least one of the luminescent markers contains an additional luminescent material that produces a small spectral difference between the two luminescent markers.

[0027] For example, the first luminescent marker M1 can contain only a single luminescent material A, and the second luminescent marker M2 can be generated by mixing luminescent material A with a small amount of additional luminescent material ε, thereby slightly altering the emission spectrum of luminescent material A. This process can be schematically illustrated by M1=A and M2=A+ε.

[0028] Optionally, the two luminescent markers may each contain a small amount but different amounts of additional luminescent material ε, λ1 and λ2, respectively, i.e., schematically M1=A+λ1ε and M2=A+λ2ε, where λ1≠λ2. The two luminescent markers may also each contain a small amount of different luminescent materials ε1 and ε2, i.e., schematically M1=A+ε1 and M2=A+ε2.

[0029] Furthermore, two luminescent markers can be made from different luminescent materials with very similar emission spectra, which can be achieved, for example, by controlling slightly different processes in production or by slightly different chemical compositions of the raw materials.

[0030] In a favorable design, in addition to the aforementioned spectral differences, the first and second luminescent markers differ in the initiation and / or decay times of emission at one, several, or even all emission wavelengths. This further enhances the separability of the luminescent markers and thereby increases the number of possible distinguishable codes.

[0031] According to a suitable design, the first and second luminescent marks are respectively arranged in the printed color areas on the valuable document. In particular, the first and second luminescent marks can exist in visually invisible printed color areas. Alternatively, it can be specified that the first and second luminescent marks exist in visually visible printed color areas, advantageously in infrared-transparent printed color areas. The latter prevents possible absorption in the printed color from interfering with the measurement of infrared emission. Again, alternatively, a combination of visually invisible and visually visible printed color areas is also feasible. This increases design freedom.

[0032] In another equally advantageous design, the first luminous marker is arranged in the printed color area on the valuable document, while the second luminous marker is arranged in the security element applied to the valuable document, particularly in the strip or block.

[0033] The first and second sub-regions can be arranged in different ways. Preferably, the first and second sub-regions do not intersect, that is, there is no overlapping area in which both the first and second luminescent marks exist. This simplifies production, such as the printing process, and also simplifies the evaluation of luminescent characteristic measurements.

[0034] Other designs contain overlapping areas with two luminous markers. However, it is preferred here that each sub-region also contains a non-overlapping area, in which only the first or second luminous marker exists alone. Designs with overlapping areas allow for greater design freedom without sacrificing the functionality provided by the non-overlapping areas.

[0035] If the first and second sub-regions overlap only in projection along a single direction, that direction is preferably the shorter lateral direction. This ensures that, as the valuable document is transported longitudinally past the usual short-side guide sensor, the same measurement trajectory of the feature sensor can measure both the first luminous marker in the first sub-region and the second luminous marker in the second sub-region.

[0036] Advantageously, the first and second sub-regions are arranged to overlap each other, even in projections in two directions, namely longitudinal and transverse. This has the advantage that banknotes can be inspected on a processor that measures both longitudinally and laterally, and the same measuring track can be used to measure the two luminous markers separately. In the advantageous design, the two sub-regions themselves do not overlap.

[0037] In a favorable design, the luminescent feature comprises only a unique first sub-region and a unique second sub-region, wherein the first and second sub-regions are arranged in the planar region to overlap each other both in the longitudinal projection and in the transverse projection.

[0038] Alternative locations, the first and / or second sub-regions can each consist of multiple unrelated sub-regions.

[0039] In a favorable specific design, the luminescent features form the barcode, whose bar elements are formed by sub-regions with different luminescent markers. The barcode can be one-dimensional, multi-row, or two-dimensional. If A represents the first luminescent marker and B represents the second luminescent marker, then the sub-regions can be constructed, for example, in the form of ABA, ABBA, ABBAB, etc. In the case of multiple barcodes in multiple rows, it is advantageous to use the same luminescent marker A as a reference marker in each row.

[0040] One-dimensional or multi-line barcodes can, in particular, be formed by multiple, for example, three different luminescent markers A, B, and C, where one luminescent marker, for example, luminescent marker A, serves as a reference marker for accurately measuring the spectral signatures of the other luminescent markers B and C. In the case of a single barcode with multiple lines, it is advantageous to use the same luminescent marker A as a reference marker in each line. In this case, for example, only two different luminescent markers can be used for each line, i.e., for example, luminescent markers A and B in even-numbered lines, and luminescent markers A and C in odd-numbered lines.

[0041] In all designs, it can be advantageously specified that, in addition to the first and second sub-regions, the luminescent characteristics include at least one third sub-region with a third luminescent mark, different from the first and second sub-regions. This third luminescent mark has an infrared emission spectrum similar to that of the first luminescent mark, and especially even the second luminescent mark, with a spectral difference between 0.5% and 15%. It should be understood that additional sub-regions with other luminescent marks can also be provided in the same manner.

[0042] The present invention also includes a valuable file system comprising multiple valuable files of different types, wherein the valuable files in the valuable file system have all identical illuminated markers in a first sub-region and different illuminated markers in a second sub-region. The illuminated markers in the first sub-region serve as common reference markers, and the different illuminated markers in the second sub-region are used for the inspection and / or classification of valuable files.

[0043] A valuable asset file system may, for example, include a series of different banknotes with multiple different denominations. Banknotes of different denominations contain different luminescent markings in a second sub-region, but share the same reference marking in a first sub-region. By measuring the difference, banknotes of different denominations can be reliably distinguished from each other, despite the spectral similarity of the luminescent markings in the corresponding second sub-regions.

[0044] The present invention also includes a method for manufacturing a planar valuable document of the type said in which a valuable document substrate having planar regions extending in both longitudinal and transverse directions is provided.

[0045] The valuable document substrate has luminescent markers set in the surface area. The method is to place the first luminescent marker in the first sub-region and the second luminescent marker in different second sub-regions in the surface area, so that the first and second sub-regions overlap each other in the longitudinal projection and / or the lateral projection.

[0046] The first and second luminescent markers can be excited to emit light at the same wavelength and, after excitation, emit light in essentially the same emission band within the infrared spectral range. Furthermore, the first and second luminescent markers have spectrally similar infrared emission spectra, i.e., infrared emission spectra with a spectral difference between 0.5% and 15%.

[0047] In an advantageous method, the first and second luminescent marks are printed onto a substrate of a valuable document, preferably by different printing methods. Advantageous printing methods that can be used here include offset printing, gravure printing, engraving, digital printing, flexographic printing, or screen printing.

[0048] In another advantageous method, the first and second luminescent marks are printed onto the valuable document substrate using the same printing method.

[0049] In another equally advantageous method, a first luminescent mark is printed onto the valuable document substrate. A second luminescent mark is arranged in a security element, particularly in a strip or block, and the security element having the second luminescent mark is applied to or introduced into the valuable document substrate.

[0050] Finally, the present invention also includes a method for inspecting planar valuable documents of the type described above, wherein the emission of light from two luminescent markers in first and second sub-regions is detected together, or the planar valuable document is transported and the emission of light from two luminescent markers in the first and second sub-regions is detected by a sensor during transport, and wherein the spectral characteristics of the second luminescent marker are evaluated relative to the spectral characteristics of the first luminescent marker. Based on the evaluation result, a truth signal representing the evaluation result can then be formed and output. To detect emission, the sub-regions are excited by a radiation source through excitation radiation of an excitation wavelength. The radiation source may preferably be part of a sensor.

[0051] The emission of light from the two luminescent markers is advantageously detected together, i.e., the emission of light from the two luminescent markers is detected directly and sequentially, for example, along a measurement trajectory that sweeps across two sub-regions during the continuous transport of a valuable document through the sensor. The measurement trajectory is advantageously parallel to the longitudinal or transverse orientation of the surface region. Therefore, in this method, the valuable document can be transported, in particular, parallel to its longitudinal or transverse direction.

[0052] Advantageously, the emission of light from two luminescent markers is detected by a single-track or multi-track luminescent sensor with at least two spectral channels. The sensor may therefore include a single-track or multi-track luminescent sensor with at least two spectral channels.

[0053] Other embodiments and advantages of the present invention are described below with reference to the accompanying drawings, in which no scale or proportion is shown in order to improve readability.

[0054] In the attached image:

[0055] Figure 1 The diagram shows a banknote extending in a face region with a vertical axis L and a horizontal axis Q.

[0056] Figure 2 Emission spectra of the first and second luminescent markers are shown in (a), and the difference spectrum between the two emission spectra is shown in (b).

[0057] Figure 3 The emission spectra of the two different combinations of luminescent markers are shown in (a) and the corresponding difference spectra are shown in (b).

[0058] Figure 4 and Figure 5 The emission spectra of the two luminescent markers are shown in (a) and the corresponding difference spectra are shown in (b).

[0059] Figure 6 A schematic diagram of another banknote design showing sub-regions with spectrally similar luminescent markers is shown.

[0060] Figure 7 Other layouts of sub-regions with spectrally similar luminescent markers in the planar region are shown in (a) to (c).

[0061] Figure 8 (a) shows two comparative banknotes with two luminescent markers, and (b) shows a histogram of the number of measurement results plotted based on spectral position.

[0062] Figure 9 (a) shows two banknotes with two luminescent markers and one reference marker, and (b) shows a histogram of the number of measurement results plotted based on relative spectral positions.

[0063] Figure 10 Showing the inspection Figure 1 A schematic diagram of the device for making banknotes, and

[0064] Figure 11 Showing through Figure 10 Device inspection Figure 1 A rough schematic flowchart illustrating the process of making banknotes.

[0065] The invention will now be explained using an example of banknote authenticity verification. Figure 1 A schematic diagram of banknote 10 is shown, which has a surface area with a vertical axis L and a horizontal axis Q. The banknote 10 has a luminous feature 12 in the surface area, which includes a first luminous mark in a first sub-region 14 and a second luminous mark in a second sub-region 16.

[0066] exist Figure 1 In this embodiment, the first and second sub-regions 14 and 16 do not intersect, i.e., they do not overlap, but are arranged spaced apart from each other in the surface region. Importantly, the two sub-regions 14 and 16 are arranged in the surface region such that they overlap in their projections onto the transverse direction Q of the banknote 10. The projections 14-P of sub-region 14 and 16-P of sub-region 16 on the transverse direction Q overlap. Figure 1 As shown on the right. As shown in the figure, the two projections 14-P and 16-P overlap in the overlapping region 18.

[0067] This ensures that when the banknote 10 is scanned by the feature sensor along the longitudinal direction L of the measurement trajectory 20 in the inspection device, not only the sub-region 14 with the first luminous mark, but also the sub-region 16 with the second luminous mark are scanned successively at short time intervals.

[0068] The luminescent markers in subregions 14 and 16 can be excited at the same wavelength, or excitation wavelength, and after excitation, they emit light in essentially the same emission band within the infrared spectral range. The emission bands are respectively given by the associated wavelength range or interval near the maximum intensity of the emission spectrum in the infrared spectral range, where the intensity is greater than 5% of the maximum intensity of the emission spectrum in the infrared spectral range. As explained in detail below, the luminescent markers are matched to each other such that their emission spectra are very similar to each other spectrally and are affected by environmental and measurement conditions in the same way. By directly comparing the emission of two luminescent markers when measured along the same measurement trajectory using the same detector or sensor, subtle differences between two spectra that are usually undetectable due to fluctuations in the measurement signal under different structurally identical detectors, different measurement trajectories, or different environmental conditions can also be reliably identified and separated.

[0069] To explain in more detail, Figure 2 Figure 30 in (a) shows the emission spectrum 34 of the first luminescent marker in the first sub-region 14 and the emission spectrum 36 of the second luminescent marker in the second sub-region 16, recorded in arbitrary units based on wavelength as intensity normalized to the emission maximum. As can be seen from the figure, emission spectra 34 and 36 are very similar to each other, except that the emission maximum of the spectrum 36 of the second luminescent marker is slightly offset relative to the emission maximum of the spectrum 34 of the first luminescent marker.

[0070] To quantify spectral similarity, Figure 2 (b) Figure 32 shows the difference spectrum 38 of the two emission spectra 34 and 36, which has a maximum and a minimum value due to the relative shift in the peak wavelengths of the two spectra. Within the scope of this description, the spectral difference between the two emission spectra 34 and 36 is defined, for example, as the maximum value of the difference spectrum 38 of the emission spectra normalized to the emission maximum value, expressed as a percentage. Figure 2 In one embodiment, the maximum value of the difference spectrum 38 at the position of the maximum value 38-Max or the minimum value 38-Min is 0.1, so that the spectral difference between the two emission spectra is 10%.

[0071] Figure 3 China and Israel Figure 2 The diagram illustrates the emission spectrum of another combination of the first and second luminescent markers, where the peak wavelengths of the emission spectra shift even less when excited by the excitation wavelength. Figure 3 Figure 40 in (a) shows the emission spectrum 44 of the first luminescent marker and the emission spectrum 46 of the second luminescent marker. Figure 3 (b) Figure 42 shows the difference spectrum 48 of the two emission spectra 44 and 46. The maximum value of the difference spectrum 48 in the two luminescent markers is only 0.043, so the spectral difference between the two emission spectra is 4.3%.

[0072] Figure 4 The same diagram shows another combination of emission spectra of the two luminescent markers, which show the same primary emission 50 and differ only in the position of the maximum value of the secondary emission 52. Figure 4 (a) shows the emission spectrum 54 of the first luminescent marker and the emission spectrum 56 of the second luminescent marker. Figure 4 (b) shows the difference spectrum 58 of the two emission spectra 54 and 56. Since the main emission 50 of the two luminescent markers is the same, the difference spectrum 58 deviates by approximately zero only in the region of the secondary emission 52, and shows a maximum deviation of 0.024 between the two spectra, which is a spectral difference of 2.4%.

[0073] Figure 5 Another variation is shown, in which the emission spectra of two luminescent markers are shown, displaying the same primary emission 60 but secondary emission 62 with different intensities.

[0074] Figure 5 (a) shows the emission spectrum 64 of the first luminescent marker and the emission spectrum 66 of the second luminescent marker. Intensity Int is plotted on the vertical axis and wavelength λ is plotted on the horizontal axis.

[0075] Figure 5(b) shows the difference spectrum 68 of the two emission spectra 64 and 66. Here, since the same primary emission 60, the difference spectrum 68 is also non-zero only in the region of the secondary emission 62, and shows a maximum deviation of 0.1 between the two spectra, i.e., a spectral difference of 10%.

[0076] To check the banknote 10, you can use Figure 10 The apparatus shown is for inspecting planar valuable documents. This apparatus may be part of an apparatus (not shown) for processing valuable documents. This includes a conveying device 136 for conveying the valuable document 10 along a conveying direction T past a sensor 138, which detects the light emission of the valuable document 10. In this example, the sensor 138 is a light emission sensor configured to detect the valuable document 10. Figure 1 The banknote emits light and forms a detection signal, which reflects the characteristics of the detected light emission, especially its spectral characteristics. The evaluation device 140 is connected to the sensor 138 via a signal connection that processes the detection signal formed by the sensor 138 during the transmission of the valuable document through the same sensor 138.

[0077] Sensor 138 includes, in particular, a radiation source for emitting radiation of an excitation wavelength toward the valuable document to be inspected, and a detector for spectrally resolving the emission of light generated by the excitation radiation.

[0078] To examine valuable documents, for example... Figure 1 The banknote 10 is conveyed by the conveying device 136 through the sensor 138. In this example, the valuable document is oriented relative to the conveying device such that the long side of the valuable document extends parallel to the conveying direction T of conveying the valuable document 10.

[0079] Perform the following steps of the method used to examine valuable documents.

[0080] In step S10, at least one emission from the luminescent marker in the first sub-region is detected by sensor 138, as it is the first to arrive at the detection area of ​​sensor 138. A first detection signal reflecting the spectral characteristics of the detected emission is formed here. This signal is then transmitted to the evaluation device 140.

[0081] In step S12, at least one emission of light from the luminescent marker in the second sub-region is detected by sensor 138, i.e., the same sensor, since it arrives in the detection region of sensor 138 after the first sub-region. A second detection signal reflecting the spectral characteristics of the detected emission is thus formed. This signal is also transmitted to the evaluation device 140.

[0082] In step S14, the evaluation device 140 then evaluates the spectral characteristics of the first luminescent marker, or the emission spectral characteristics of the first luminescent marker, relative to the spectral characteristics of the second luminescent marker, using the transmitted first and second detection signals. Based on the evaluation results, a veracity signal representing the evaluation results is then formed and output. The veracity signal can be output to a device that controls further processing of the valuable document.

[0083] In addition to Figure 1 The design, in which two exactly non-intersecting sub-regions 14 and 16 with spectrally similar luminescent markers overlap only in their lateral projections, is feasible and advantageous in other ways. For example, refer to... Figure 6 The luminescent feature 72 of the banknote 70 may include a first sub-region 74 and a non-intersecting second sub-region 76, wherein the sub-regions 74 and 76 overlap in both the projection of the banknote 70 onto the longitudinal direction L and the transverse direction Q.

[0084] Thus, when scanning banknotes along the longitudinal measurement trajectory 20 and the transverse measurement trajectory 22, the two sub-regions 74 and 76 can be scanned by the feature sensor respectively, enabling banknotes 70 to be inspected not only in the longitudinal direction but also in the transverse direction in the banknote processing machine.

[0085] Figure 7 Other advantageous layouts with spectrally similar luminescent markers are shown in the diagram. Figure 7 (a) Here is shown a surface region 80 of a valuable document having multiple spaced-apart first sub-regions 84 with first luminous markers and a single second sub-region 86 with a second luminous marker. Measurement trajectories 20, 22 also detect the first and second sub-regions in the longitudinal or transverse direction, respectively, so that the valuable document having surface region 80 can be examined by longitudinal or transverse measurement.

[0086] The same function can be achieved by... Figure 7 (b) is designed and implemented in a manner in which the surface region 80 has multiple spaced-apart first sub-regions 84 with first luminous markers and multiple spaced-apart second sub-regions 86 with second luminous markers. Measurement trajectories 20 and 22 detect the first and second sub-regions respectively in the longitudinal or transverse direction.

[0087] In other designs, the first and second sub-regions are not non-intersecting, but rather constructed in a regional overlapping manner, such as... Figure 7 As shown in (c), the surface region 80 in this design includes a first sub-region 84 with a first luminous marker and a second sub-region 86 with a second luminous marker, which overlap in the overlapping region 88. Importantly, there are also non-overlapping regions where only the first or second luminous marker exists. Figure 7As shown in (c), measurement trajectories 20 and 22 detect non-overlapping areas of the first and second sub-regions 84 and 86 in the longitudinal or transverse directions, respectively, thus allowing for difference assessment of the measurement signals as described in the design so far.

[0088] To demonstrate the advantages of the present invention, a comparison is made between the luminescence measurement on a banknote according to the present invention and the corresponding measurement on a comparative banknote having conventional luminescence characteristics.

[0089] first, Figure 8 (a) shows two comparative banknotes 90 and 94, each printed with an infrared-excited and infrared-emitting luminescent mark in sub-region 92 or 96, respectively. Sub-region 92 of the first comparative banknote 90 contains the luminescent mark "B", and sub-region 96 of the second comparative banknote 94 contains the luminescent mark "C", wherein the spectral difference between the two luminescent marks is 3%.

[0090] To simulate banknote inspection under real-world usage conditions, banknotes 90 and 94 are compared at multiple transport speeds between 1 m / s and 11 m / s using three structurally identical feature sensors, and measurements are taken at multiple measurement points within corresponding sub-regions 92 and 96. The measured values ​​are used to determine a measure of the spectral position of the emission of the two luminescent markers, such as a local emission maximum or the spectral centroid of the emission band. Alternatively, the spectral centroid of the emission band, for example, the wavelength of the emission maximum or another spectral feature, such as the second maximum, minimum, or shoulder wavelength in the emission spectrum, can also be used as a measure of the spectral position.

[0091] Figure 8 (b) Histogram 100 shows the number N of measurement results recorded based on the determined spectral positions for the two luminescent markers “B” and “C”, respectively. As can be seen from the figure, the distributions 102 and 104 of the determined spectral positions for the two luminescent markers have non-negligible overlap, making it impossible to reliably distinguish the two markers due to the magnitude of the fluctuations. These fluctuations could be caused by variations, for example, between sensors with nominally identical structures, or by changes in environmental conditions, such as temperature, transport distance, or transport speed.

[0092] Figure 9 (a) Two banknotes 110 and 120 according to the present invention are shown, which may, for example, be part of the aforementioned valuables file system. In addition to the aforementioned luminescent marks “B” and “C”, banknotes 110 and 120 each include an additional luminescent mark “A” as a reference mark. The emission spectrum of luminescent mark “A” is located between the emission spectra of luminescent marks “B” and “C”, and is therefore spectrally similar to both luminescent marks, with a spectral difference of about 0.5% or about 3%.

[0093] Specifically, in such Figure 1In the configuration shown, banknote 110 has an luminous mark "A" for comparison banknote 90 printed in the first sub-region 114, and an luminous mark "B" for comparison banknote 90 printed in the second sub-region 116. The two sub-regions 114 and 116 overlap in their projection onto the horizontal direction Q, and both can be detected by measuring the trajectory.

[0094] The 120 banknote is also in such a situation. Figure 1 In the configuration shown, the luminous mark "A" of the comparison banknote 94 is printed in the first sub-region 124, and the luminous mark "C" of the comparison banknote 94 is printed in the second sub-region 126. These two sub-regions 124 and 126 also overlap in their projection onto the horizontal Q direction, and both can be detected by measuring the trajectory.

[0095] According to the invention, banknotes 110 and 120 are then measured at multiple measurement points in corresponding sub-regions 114, 116, or 124, 126, using the same three feature sensors with the same structure as the comparison banknotes and the same conveying speed between 1 m / s and 11 m / s.

[0096] Here, the spectral positions of the light emission of the second sub-region 116 of banknote 110 with the light-emitting mark "B" and the second sub-region 126 of banknote 120 with the light-emitting mark "C" are not absolute, but are determined relative to the light emission of the light-emitting mark "A" of the corresponding first sub-region 114 or 124.

[0097] Figure 9 (b) Histogram 130 shows the spectral position relative to the luminescent marker “A”. Figure 9 (b) The number of measurements N obtained by plotting the spectral positions of the two luminescent markers “B” and “C” respectively, which are the zero points in the diagram.

[0098] Because fluctuations occurring during measurement, such as variations between three nominally identical sensors (e.g., filter tolerances or optical tolerances) or changes in environmental conditions (e.g., temperature, transport distance, transport speed), have the same impact on the measurement of the spectral positions of the two sub-regions 114 and 116 or 124 and 126, these fluctuations are largely compensated for in the difference assessment and produce a significantly smaller distribution width in the histogram 130 of the relative spectral positions. Figure 9 As shown in (b), the distributions 132 and 134 of the difference measurement results for the luminescent markers “B” and “C” are clearly separated from each other, and the two luminescent markers can be reliably distinguished based on their relative spectral positions.

[0099] The examination of valuable documents according to the invention can be performed, in particular, by a single-track or multi-track emission sensor having at least two spectral channels K1, K2, which can detect differences in the luminescent markings used on the valuable document through the spectral channels. Advantageously, the two spectral channels detect closely adjacent or even directly adjacent spectral regions of the emission spectrum. For example, if the emission bands of the two luminescent markings are approximately centered spectrally between the spectral sensitivity ranges of the two spectral channels, a small shift in the peak wavelength can be determined with high precision.

[0100] For example in Figure 2 In the emission spectra 34 and 36, wavelengths below the center wavelength λ can be selected. z The spectral channel at position K1 and above the center wavelength λ z A second spectral channel at position K2, at the same distance from the center wavelength. It is also advantageous to use a spectral channel with a width of a few nanometers, for example, 2 to 50 nanometers.

[0101] In another design, multiple, such as 4, 10, 20 or even 100 spectral channels are used to precisely scan the shape of the emission spectrum.

[0102] In another variation, the spectral channels of the emission sensor are adapted to define more complex emission spectra, allowing individual peaks of the emission spectrum to be detected through fewer different channels. For example, in Figure 4 In the emission spectra 54 and 56, a feature sensor with three spectral channels can be used to detect the emission at the wavelength positions shown in the figure, that is, on the one hand, in the region of the maximum value of the main emission 50 at position K1, and on the other hand, symmetrically on both sides of the maximum value of the secondary emission 52 at positions K2 and K3.

[0103] exist Figure 5 In the emission spectra 64 and 66, a feature sensor with two spectral channels is sufficient to detect the emission in the maximum region of the primary emission 60 at position K1 and the maximum region of the secondary emission 62 at position K2.

[0104] List of reference numerals

[0105] 10 banknotes

[0106] 12 Luminous Characteristics

[0107] Subregions 14 and 16

[0108] 14-P and 16-P projections

[0109] 18 overlapping regions

[0110] Measurement trajectories 20 and 22

[0111] Charts 30 and 32

[0112] 34, 36 emission spectra

[0113] 38 difference spectrum

[0114] Maximum and minimum values ​​of the 38-Max and 38-Min difference spectra

[0115] Charts 40 and 42

[0116] 44, 46 emission spectra

[0117] 48 difference spectrum

[0118] 50 main launchers

[0119] 52 launches

[0120] 54, 56 emission spectra

[0121] 58 difference spectrum

[0122] 60 main launch

[0123] 62 launches

[0124] 64, 66 emission spectra

[0125] 68 difference spectrum

[0126] 70 banknotes

[0127] 72 luminescence characteristics

[0128] Subregions 74 and 76

[0129] 80-sided area

[0130] Subregions 84 and 86

[0131] Comparison of 1990 and 1994 banknotes

[0132] Sub-regions 92 and 96 with luminescent markers

[0133] 100 histogram

[0134] 102, 104 distribution

[0135] 110 banknotes

[0136] 114 has the first sub-region with luminescent marker A

[0137] 116 has a second sub-region with luminescent marker B.

[0138] 120 banknotes

[0139] 124 has the first sub-region with luminescent marker A

[0140] 126 has a second sub-region with luminescent marker C

[0141] 130 histogram

[0142] Distributions of 132 and 134

[0143] 136 Conveying Device

[0144] 138 light sensor

[0145] 140 evaluation device

[0146] L longitudinal

[0147] Q horizontal

[0148] K1, K2, K3 spectral channels

[0149] T conveying direction

Claims

1. A planar valuable document (10) having a planar region with longitudinal (L) and transverse (Q) dimensions, and having a light-emitting feature (12) disposed in the planar region, characterized in that, - The luminescent feature (12) includes a first luminescent marker in a first sub-region (14) and a second luminescent marker in different second sub-regions (16). - The first and second luminescent markers can be excited to emit light at the same wavelength, and after excitation, they emit light in the same emission band within the infrared spectral range. The first and second luminescent markers have similar infrared emission spectra, i.e., infrared emission spectra with a spectral difference between 0.5% and 15%. - The first and second sub-regions are arranged in the surface region to overlap each other in the projection in the longitudinal direction (L) and / or in the projection in the transverse direction (Q).

2. The planar valuable document according to claim 1, characterized in that, The first and second luminescent markers have a spectral difference between 1% and 11%.

3. The planar valuable document according to claim 1, characterized in that, The first and second luminescent markers have a spectral difference between 2% and 7%.

4. The planar valuable document according to claim 1, characterized in that, The first and second luminescent markers can be excited by wavelengths in the range of 700 to 2500 nm, and / or the first and second luminescent markers emit light in the range of 700 to 2500 nm after excitation.

5. The planar valuable document according to claim 4, characterized in that, The first and second luminescent markers can be excited by wavelengths in the range of 900 to 2100 nm, and / or the first and second luminescent markers emit light in the range of 900 to 2100 nm after excitation.

6. The planar valuable document according to claim 1, characterized in that, The first and second luminescent markers do not exhibit upconversion.

7. The planar valuable document according to claim 6, characterized in that, The first and second luminescent markers do not emit light in the visible spectrum after excitation.

8. The planar valuable document according to claim 1, characterized in that, The first and / or second luminescent markers contain organic, organometallic, or inorganic luminescent materials.

9. The planar valuable document according to claim 1, characterized in that, The first and second luminescent markers each contain only a single luminescent material.

10. The planar valuable document according to claim 1, characterized in that, The first and second luminescent markers contain a common luminescent material, and at least one of the luminescent markers contains an additional luminescent material.

11. The planar valuable document according to claim 1, characterized in that, The first and second luminescent markers are distinguished by the initiation time and / or decay time of emission at one, multiple, or all emission wavelengths.

12. The planar valuable document according to claim 1, characterized in that, The first and second luminous markers are respectively arranged in the printed color area on the valuable document, or the first and second luminous markers exist in the visually visible printed color area.

13. The planar valuable document according to claim 12, characterized in that, The first and second luminescent marks are located in a visually invisible printed color area, or the first and second luminescent marks are located in an infrared-transparent printed color area.

14. The planar valuable document according to claim 1, characterized in that, The first luminous marker is arranged in the printed color area on the valuable document, and the second luminous marker is arranged in the security element applied to the valuable document.

15. The planar valuable document according to claim 14, characterized in that, The second luminous marker is arranged in a strip or block applied to the valuable document.

16. The planar valuable document according to claim 1, characterized in that, The first and second subregions do not overlap.

17. The planar valuable document according to claim 1, characterized in that, The luminescent features consist of only a unique first sub-region and a unique second sub-region, and the two sub-regions are arranged in the planar region to overlap each other both in the longitudinal projection and in the transverse projection.

18. The planar valuable document according to claim 1, characterized in that, The luminescent features form the barcode, and the bar elements of the barcode are formed by sub-regions with different luminescent markers.

19. The planar valuable document according to claim 1, characterized in that, The luminescence characteristics include at least one distinct third sub-region with a third luminescent marker having an infrared emission spectrum similar to that of the first and second luminescent markers, with a spectral difference between 0.5% and 15%.

20. The planar valuable document according to claim 1, characterized in that, The face-shaped valuable document (10) is a banknote.

21. A valuable file system comprising a plurality of different valuable files according to any one of claims 1 to 20, wherein, The valuable files in the valuable file system have all the same glowing markers in the first sub-region, and different glowing markers in the second sub-region.

22. A method for manufacturing a planar valuable document (10) according to any one of claims 1 to 20, wherein, A valuable file substrate is provided having surface regions extending along the longitudinal (L) and transverse (Q) directions, and luminescent features (12) are provided in the surface regions. - The first luminous marker is placed in the first sub-region (14), and the second luminous marker is placed in different second sub-regions (16) in the surface region such that the first and second sub-regions overlap each other in the projection to the longitudinal direction (L) and / or the transverse direction (Q). -The first and second luminescent markers can be excited to emit light at the same wavelength, and after excitation, they emit light in the same emission band within the infrared spectral range. -In addition, the first and second luminescent markers have infrared emission spectra that are spectrally similar, i.e., infrared emission spectra with a spectral difference between 0.5% and 15%.

23. The method according to claim 22, characterized in that, The first and second luminescent markers are printed onto the valuable document substrate using different printing methods.

24. The method according to claim 22 or 23, characterized in that, A first luminescent mark is printed onto the valuable document substrate, a second luminescent mark is arranged in a security element, and a security element having the second luminescent mark is applied to or introduced into the valuable document substrate.

25. A method for examining a planar valuable document according to any one of claims 1 to 20, wherein - The planar valuable document (10) is transported and the emission of light from two luminous markers in the first and second sub-regions (14, 16) is detected by sensors during transport, or the emission of light from two luminous markers in the first and second sub-regions (14, 16) is detected together. - Evaluate the spectral properties of the second luminescent marker relative to the spectral properties of the first luminescent marker.

26. The method according to claim 25, characterized in that, The emission of two luminous markers is detected together by directly and successively detecting the emission of the two luminous markers along the measurement trajectory that sweeps through the two sub-regions.

27. The method according to claim 26, characterized in that, The measurement trajectory is parallel to the longitudinal or transverse orientation of the surface area, or parallel to the longitudinal or transverse transport of the valuable document.

28. The method according to any one of claims 25 to 27, characterized in that, The emission of light from two luminescent markers is detected by a single-track or multi-track luminescent sensor having at least two spectral channels, or the sensor includes a single-track or multi-track luminescent sensor having at least two spectral channels.

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