Security device having a machine-readable feature region, value document and test method
By arranging IR characteristic areas with atypical and typical absorption behaviors on the foil carrier of the safety device, effective distinction between forgery and enhanced anti-counterfeiting is achieved, the problem of easy counterfeiting of IR absorbed substances in the prior art is solved, and safety is improved The protective effect of the device.
Patent Information
- Application Number
- CN202410841721.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-06-29
- Filing Date
- 2024-06-27
- Publication Date
- 2024-12-31
AI Technical Summary
Existing safety devices with IR absorbing substances are easy to forge, have small protective effects, and it is difficult to effectively distinguish between forged and true IR signals in authenticity testing.
Design a safety device with two machine-readable feature regions arranged on the foil carrier, one of which contains IR absorbing substances with absorption maximums between 800 nm and 1000 nm, exhibiting atypical absorption behavior, and the other IR substances containing typical absorption behaviors are subject to bilateral detection and signal comparison of IR signals to evaluate authenticity.
It significantly improves the barrier properties of counterfeiting, and it is difficult to forge IR substances through atypical absorption behavior, enhances the anti-counterfeiting of security devices, and provides multiple authentication features through multiple encoding possibilities.
Smart Images
Figure CN119227715A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a security device having a machine-readable characteristic region, which has an IR-absorbing substance, a valuable document having such a security device, and a method for testing such a security device. Background Art
[0002] For protection, data carriers (eg securities or identification documents, as well as other valuable objects, such as branded articles) are usually equipped with a security element which allows the authenticity of the data carrier to be tested and at the same time serves as protection against unauthorized copying.
[0003] In order to facilitate automatic authenticity testing and, if applicable, advanced sensor-based detection and processing of the data carrier provided therewith, the security element is usually formed to be machine-readable. For this purpose, the security element is provided with, for example, an infrared (IR) absorbing substance, the IR signature of which can be detected by an infrared sensor machine and can be evaluated when testing authenticity.
[0004] However, known security elements with IR-absorbing substances are generally relatively easy to reconstruct and therefore have only a small protective effect. Summary of the invention
[0005] Starting from this, the object of the present invention is to specify a universal security device with increased resistance to forgery. The present invention is also intended to provide a value document with such a security device and a method for testing such a security device.
[0006] This object is achieved by the features of the independent claim. Developments of the invention are the subject matter of the dependent claims.
[0007] The present invention includes a security device having a foil carrier with opposing major surfaces and having two machine-readable feature areas arranged on the opposing major surfaces of the foil carrier.
[0008] The machine-readable feature regions comprise in each case an IR-absorbing substance, at least one of the machine-readable feature regions comprising an IR-absorbing substance having an absorption maximum between 800 nm and 1000 nm.
[0009] In the following, for the sake of simplicity, IR absorbing substances are also often referred to as IR substances or IR materials for short. As explained in more detail below, IR absorbing substances usually show an absorption behavior with a relatively gentle absorption minimum in the wavelength range between 800 nm and 1000 nm. Therefore, the IR remission of such IR substances shows a relatively gentle maximum in the wavelength range of 800 nm to 1000 nm and then slowly decreases again towards larger wavelengths.
[0010] Thus, the IR substances used according to the invention having an absorption maximum and a corresponding reflection minimum between 800 nm and 1000 nm show an atypical absorption behavior and can therefore be reliably distinguished from conventional IR substances in authenticity tests. Since IR substances with an atypical absorption behavior are more difficult for counterfeiters to obtain than conventional IR substances, the barrier to counterfeiting is significantly increased.
[0011] Additionally, since the machine-readable feature areas with IR absorbing substance are present on two opposing sides of the foil carrier, the security device can be tested from both sides in an authenticity test and the presence of the IR signal can be compared to the expected signal to assess the authenticity of the security device.
[0012] In an advantageous embodiment, both machine-readable feature regions comprise an IR substance having an absorption maximum between 800 nm and 1000 nm.
[0013] In another likewise advantageous embodiment, only one of the machine-readable characteristic regions comprises an IR substance having an absorption maximum between 800 nm and 1000 nm, while the other of the machine-readable characteristic regions comprises an IR substance having no absorption maximum between 800 nm and 1000 nm. The latter IR substance is in particular a conventional IR substance having a typical absorption behavior, i.e. a flat absorption minimum in the mentioned wavelength range.
[0014] In a particularly advantageous embodiment, the IR substance present in at least one of the characteristic regions and having an atypical absorption behavior has a significantly higher absorption at a wavelength of 950 nm than at a wavelength of 850 nm, in particular at least 3% higher, at least 5% higher or even at least 8% higher.
[0015] IR substances with atypical absorption behavior have their absorption maximum in particular between 940 nm and 980 nm.
[0016] It is advantageously provided that the IR substance which is present in at least one of the characteristic regions and has an atypical absorption behavior has a reflection of 60% or less in the wavelength range of 800 nm to 1000 nm.
[0017] On the security device, in the projection, the two machine-readable characteristic regions advantageously overlap each other at least in some regions. This enables the two characteristic regions to cooperate in the overlapping region and, in doing so, to form, for example, a machine-readable transparent register or a shared machine-readable code.
[0018] In a preferred embodiment, the two machine-readable characteristic regions each form a machine-readable code, which can be formed in particular by the shape and size of the machine-readable characteristic region and / or by the shape and size of the gap in the machine-readable characteristic region. The two machine-readable characteristic regions together particularly advantageously form an additional machine-readable code, the presence of which can be evaluated as an authentication feature. In this way, the security device can provide a variety of coding possibilities.
[0019] Furthermore, a specifically selected combination of the IR substances of the two characteristic regions can also be used as a secret code for characterizing the security device or a valuable document provided therewith.
[0020] According to an advantageous embodiment, two machine-readable characteristic regions are present continuously on the foil carrier in each case. Also in the continuous characteristic regions, the position dependence of the IR signal can be caused, for example, by different concentrations of the IR substance in some regions, or by the embedding of the security device in the target document. For example, a window security thread can be provided continuously on both sides with machine-readable characteristic regions and partially embedded in the paper substrate of the banknote, so that when measuring the front side, the IR reflection signal is detected only in the window area, and not in the middle web area of the paper substrate. Similarly, when measuring the reverse side, the IR reflection signal can be detected only in the area opposite to the web area of the front side, and not in the area opposite to the window area of the front side, as described in more detail below.
[0021] However, it is currently particularly preferred that one or both of the machine-readable characteristic regions are structured in the form of a pattern, character or code. The structured formation of the characteristic region in particular allows easy generation of spatial codes, such as bar codes.
[0022] In a development of the invention, the at least one machine-readable feature area is covered in some areas by a paper web or an IR barrier.The paper web or the IR block may also be part of the target document in which the security device according to the invention is embedded.
[0023] The safety device is advantageously a safety element, in particular a safety wire or a safety belt.
[0024] Here, the invention also includes a valuable document, in particular a banknote, having such a security element, wherein in an advantageous embodiment the security element is at least partially embedded in the interior of the valuable document.
[0025] In another equally advantageous development, the security device itself is a valuable document, in particular a banknote.
[0026] Finally, the invention also comprises a method for testing a security device of the described type, wherein the security device is irradiated with IR radiation, the IR radiation reflected by the security device is measured as an IR signal, and based on the measured IR signal it is determined whether the security device comprises a characteristic area having an IR-absorbing substance, the absorption maximum of which is between 800 nm and 1000 nm.
[0027] In the method, advantageously both the front side and the back side of the security device are irradiated with IR radiation and the IR radiation reflected by the security device is measured in each case as an IR signal.
[0028] Here, it may be advantageously determined whether the security device comprises two characteristic regions of IR substance with atypical absorption behavior or one characteristic region of IR substance with atypical absorption behavior and one characteristic region of IR substance with typical absorption behavior. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Further exemplary embodiments and advantages of the invention are explained below with reference to the accompanying drawings, in which the depiction of comparative scales is omitted in order to improve their clarity.
[0030] Figure 1 Schematically showing a cross-sectional view of a banknote with a window security thread according to the present invention,
[0031] Figure 2 Schematic diagram showing the detection of the IR sensor Figure 1 Appearance of the banknotes in the diagram, in each case from above, (a) from the front, (b) from the back,
[0032] Figure 3 Schematic diagram showing the IR reflection of an IR substance with atypical absorption behavior compared to the IR reflection of two IR substances with typical absorption behavior,
[0033] Figure 4 yes Figure 2 a modification of the exemplary embodiment of , in which the window security thread comprises an IR substance with atypical absorption behavior only in its bottom side coating,
[0034] Figure 5is another exemplary embodiment of the present invention, wherein (a) schematically shows a cross-sectional view of a banknote with a window security line according to the present invention, (b) and (c) schematically show the appearance detected by an IR sensor when the banknote is viewed from the front and back, respectively,
[0035] Figure 6 In such Figure 5 On the basis of the illustrated figure, another exemplary embodiment of the present invention is shown, in which both the upper coating and the lower coating of the window security thread are developed to be structured,
[0036] Figure 7 In such Figure 5 On the basis of the figures shown, a further exemplary embodiment of the invention is shown, in which the security element according to the invention is not embedded in a paper bank note, but forms part of a polymer bank note, and
[0037] Figure 8 In such Figure 5 On the basis of the figures shown, a further exemplary embodiment of the invention is shown, in which the security device is formed by a polymer banknote. DETAILED DESCRIPTION
[0038] The invention will now be explained using the example of a bank note and a security element for a bank note. Figure 1 A banknote 10 according to the invention with a window security thread 20 is schematically shown in cross section. Here, the window security thread 20 is partially embedded in the paper substrate 12 of the banknote 10, so that it appears on the surface of the banknote in the window area 14, while it is embedded in the interior of the paper substrate 12 in the middle web area 16.
[0039] The window security thread 20 comprises a carrier foil 22 having opposite upper and lower main surfaces. As a distinguishing feature, the two main surfaces in each case form a machine-readable feature area which is continuously provided with a coating 24 or 26 comprising a specific IR substance 28. The specific IR substance 28 is an IR substance with an atypical absorption behavior, i.e. with a clear absorption maximum between 800 nm and 1000 nm.
[0040] To explain in more detail, Figure 3The IR reflection of the IR substance 28 used (reflection curve 40) is schematically shown in comparison with the IR reflection of two IR substances with typical absorption behavior (reflection curves 42, 44). In the wavelength range between 800 nm and 1000 nm, IR substances with typical absorption behavior include a generally flat absorption minimum, so that the IR reflection in the wavelength range thus shows a flat maximum and slowly decreases again towards higher wavelengths. Here, the reflection curve 42 originates from a first IR substance with relatively low absorption and therefore high reflection, while the reflection curve 44 originates from a second IR substance with relatively high absorption and therefore low reflection.
[0041] In contrast, the IR reflection 40 exhibited by the specific IR substance 28 has a high reflection value at a wavelength of about 850 nm and a distinct minimum at a wavelength of about 950 nm, after which the reflection increases again toward a wavelength of 1000 nm. At the same time, in the range of 800 nm to 1000 nm, the reflection of the IR substance 28 advantageously does not exceed 60%.
[0042] One such specific IR substance can be produced, for example, using an IR-absorbing printing ink which is available from the company SICPA under the trade name NFB was obtained commercially.
[0043] It will be appreciated that the exact progression of the reflectance curve and the precise magnitude of the IR reflectance will depend on the specific IR material used. Figure 3 It is used schematically only to illustrate the difference between typical and atypical absorption behavior.
[0044] Figure 2 Now the schematic diagram of the IR sensor is shown. Figure 1 The appearance of the banknote 10 in each case is from the front ( Figure 2 (a)) and from the reverse side ( Figure 2 (b)) is a top view. Figure 2 In the front measurement in (a), an IR signal 30 is measured in the window area 14, while no IR signal is detected in the web area 16. Figure 2 In the reverse side measurement in (b), the opposite appearance is produced: there, an IR signal 32 is obtained in the area 16-R opposite to the web area 16 of the front side, while no IR signal is obtained in the area 14-R opposite to the window area 14 of the front side.
[0045] The mechanism of signal formation in reflection measurement is not fully understood theoretically, because the back side signal appears in the geometry of the web area 16 on the front side, so without wishing to be bound by a certain interpretation, the IR signal 32 measured on the back side is currently attributed to the reflection of IR radiation on the web area 16 on the front side.
[0046] When tested for authenticity by an IR sensor, for example in a banknote processing machine, the banknote 10 can be tested from both the front and back sides, and the presence of an IR signal with a suitable spatial distribution on both sides can be evaluated as an indication of the authenticity or lack of authenticity of the banknote. In addition, due to its atypical absorption behavior (reflection curve 40), the IR substance 28 is easily distinguishable from other conventional IR substances with typical absorption behavior (reflection curves 42, 44).
[0047] Figure 4 Shows Figure 2 A modification of the exemplary embodiment in which the window security thread 20 comprises a specific IR substance 28 having an atypical absorption behavior only in its bottom side coating 26, while the top side coating 24 comprises an IR substance 25 having a typical absorption behavior, e.g. Figure 3 The reflectance curves 42 and 44 are of IR materials with smooth absorption minima.
[0048] Also in this exemplary embodiment, when testing authenticity by an IR sensor, the banknote 10 can be tested from both the front and back sides, and the presence of an IR signal with a suitable spatial distribution and suitable absorption behavior on both sides can be evaluated as an indication of the authenticity or lack of authenticity of the banknote.
[0049] exist Figure 5 Another exemplary embodiment of the present invention is shown in FIG. Figure 5 (a) shows a schematic cross-sectional view of a banknote 50 having a window security thread 20 according to the present invention, Figure 5 (b) and 5(c) schematically show the front view of a banknote detected by an IR sensor ( Figure 5 (b)) and the reverse side top view ( Figure 5 (c)) appearance.
[0050] Here, the characteristic regions formed by the coatings 24, 26 of the window security thread 20 each comprise an IR substance, and for the sake of simplicity, the IR substance is no longer represented by Figure 5 and symbols in subsequent figures are shown separately.
[0051] exist Figure 5 In an exemplary embodiment of Figure 2 and Figure 4 In contrast to the exemplary embodiment in FIG. 2 , the upper coating 24 of the window security thread 20 is structured, ie is present only in a sub-region of the thread surface, whereas the lower coating 26 is continuous.
[0052] exist Figure 5In the front side measurement shown in (b), IR signals 30 are obtained only at locations in the window region 14 where coating material 24 is also present, whereas no IR signal is detected in the web region 16, even if coating material is present there.
[0053] Since the lower coating layer 26 is formed continuously, Figure 5 In the reverse measurement shown in (c), the Figure 2 (b) Same appearance: in each case, an IR signal 32 is obtained in the region 16 -R opposite to the web region 16 , while no IR signal is obtained in the region 14 -R opposite to the window region 14 .
[0054] At least one of the coatings 24, 26 comprises an IR substance with atypical absorption behavior, i.e., with an absorption maximum between 800 nm and 1000 nm, and the other of the two coatings may also comprise an IR substance with typical absorption behavior. However, both coatings 24, 26 particularly preferably comprise IR substances with atypical absorption behavior.
[0055] exist Figure 6 In another exemplary embodiment of the present invention shown, Figure 6 (a) shows a cross-sectional view of a banknote 52 having a window security thread 20 according to the present invention, Figure 6 (b) and Figure 6 (c) shows the appearance of a bank note 52 detected by an IR sensor, in each case from the front side of the bank note ( Figure 6 (b)) and the reverse side ( Figure 6 (c) Schematic top view of the observation.
[0056] exist Figure 6 In the exemplary embodiment of the window security thread 20, both the upper coating 24 and the lower coating 26 are structured. At least one (advantageously both) coatings 24, 26 include an IR substance with atypical absorption behavior (ie, with an absorption maximum between 800nm and 1000nm).
[0057] exist Figure 6 In the front measurement of (b), IR signals 30 are obtained only at locations where coating material 24 is also present in window region 14, while no IR signals are detected in web region 16, even when coating material is present in web region 16. Figure 6 In the reverse measurement in (c), in the region 16 -R opposite to the web region 16 , an IR signal 32 is obtained only where the coating material 26 is still present, while no IR signal is obtained in the region 14 -R opposite to the window region 14 .
[0058] The characteristic spatial distribution of the IR signals 30 and 32 and the absorption behavior of the IR substance of the coating 24 , 26 (typical or atypical) allow a reliable authenticity test of the banknote 52 to be performed.
[0059] Figure 7 Another exemplary embodiment of the invention is shown, in which the security element is not embedded in a paper bank note, but forms part of a polymer bank note 60 .
[0060] First reference Figure 7 (a), a polymer banknote 60 comprises a polymer substrate 62, with opaque white or ink receiving layers 64 or 66 on both sides thereof. A security element 70 of the present invention is arranged between the polymer substrate 62 and the upper ink receiving layer 64, which comprises an upper feature area 74, a lower feature area 76 and a foil layer 72 located between the feature areas. In addition, an IR barrier 80 is embossed in some areas of the security element 70, so that an IR web area 86 with an IR barrier 80 and an IR window area 84 without an IR barrier are produced on the polymer banknote.
[0061] At least one of the characteristic regions 74, 76 comprises a specific IR substance with atypical absorption behavior, thus having an absorption maximum between 800nm and 1000nm. The other characteristic region may comprise an IR substance with typical absorption behavior, but both characteristic regions 74, 76 particularly preferably comprise said IR substance with atypical absorption behavior.
[0062] exist Figure 7 In the exemplary embodiment of FIG. 5 , the two characteristic regions 74 , 76 are formed to be structured, but similar to the above-described embodiment, they may also be formed to be continuous.
[0063] Figure 7 (b) shows the result of measuring the front side of the banknote 60 using the IR sensor. In the measurement, the IR signal 30 is obtained only in the IR window area 84, and the IR signal 30 is obtained only at the position where the top side feature area 74 with IR substance also exists in the IR window area. On the contrary, in the IR web area 86, due to the absorption effect of the IR barrier 80, when the IR substance exists under the IR web area, no IR signal is detected.
[0064] exist Figure 7 In the back side measurement in (c), the IR signal 32 is obtained only in the area 86-R opposite to the IR web area 86, and in the area 86-R, the IR signal 32 is obtained only at the position where the bottom side feature area 76 with IR substance exists. On the contrary, no IR signal is obtained in the area 84-R opposite to the IR window area 84 of the front side. Figure 2As explained above, the signal generation in the back-side measurement is currently due to reflections on the IR barrier 80 on the front side.
[0065] exist Figure 8 In an exemplary embodiment of the invention, the security device is not formed by a security element which is applied to or introduced into the value document, but by the value document itself.
[0066] Specifically, Figure 8 (a) shows a polymer banknote 90 with a polymer substrate 62 in cross section, the polymer substrate 62 having an opaque white or ink receiving layer 64 or 66 on both sides, respectively. An upper feature area 94 is arranged on the top of the polymer substrate 62, and a lower feature area 96 is arranged on the opposite bottom of the polymer substrate 62. In addition, an intermediate layer 92 can be provided, which can be formed by a foil layer or a printed layer. In addition, an IR barrier 80 is embossed in some areas on the upper feature area 94, so that an IR web area 86 with an IR barrier 80 and an IR window area 84 without an IR barrier are produced on the polymer banknote.
[0067] At least one of the characteristic regions 94, 96 comprises a specific IR substance with atypical absorption behavior, i.e., with an absorption maximum between 800 nm and 1000 nm. The other characteristic region may comprise an IR substance with typical absorption behavior, but both characteristic regions 94, 96 particularly preferably comprise said IR substance with atypical absorption behavior.
[0068] In the exemplary embodiment, the two characteristic regions 94 , 96 are formed to be structured, but similar to the above-described embodiment, they may also be implemented to be continuous.
[0069] Figure 8 (b) shows the front measurement of a polymer banknote 90 with an IR sensor. Here, the IR signal 30 is obtained only in the IR window area 84, and in the IR window area only at the location where the top side feature area 94 with IR substance is also present. In contrast, in the IR web area 86, no IR signal is detected due to the absorption effect of the IR barrier 80, even when IR substance is present below the web area 86.
[0070] exist Figure 8 In the opposite side measurement in (c), the IR signal 32 is obtained only in the region 86-R opposite to the IR web region 86, and in the region 86-R, the IR signal 32 is obtained only at the position where the bottom feature region 96 with the IR substance exists. On the contrary, no IR signal is obtained in the region 84-R opposite to the IR window region 84 of the front side.
[0071] Reference numerals
[0072] 10 banknotes
[0073] 12 Paper base
[0074] 14 Window Area
[0075] 14-R Area opposite to the window area
[0076] 16 Web Areas
[0077] 16-R Area opposite to the web area
[0078] 20 Window Security Line
[0079] 22 Carrier Foil
[0080] 24,26 coating
[0081] 28IR substances
[0082] 30,32IR signal
[0083] 40,42,44 reflection curve
[0084] 50,52 banknotes
[0085] 60 polymer banknotes
[0086] 62 polymer substrate
[0087] 64,66 Opaque white or ink receiving layer
[0088] 70 safety elements
[0089] 72 foil layers
[0090] 74,76 Feature Area
[0091] 80IR blocking
[0092] 84IR window area
[0093] 84-R Area opposite to the IR window area
[0094] 86IR web area
[0095] 86-R Area opposite to IR web area
[0096] 90 polymer banknotes
[0097] 92 Middle Layer
[0098] 94,96 Feature Area
Claims
1. A security device having a foil carrier with opposite main surfaces and having two machine-readable feature areas arranged on the opposite main surfaces of the foil carrier, the machine-readable feature areas each comprising an IR-absorbing substance, at least one of the machine-readable feature areas comprising an IR-absorbing substance having an absorption maximum between 800 nm and 1000 nm.
2. The safety device according to claim 1, characterized in that: Both machine-readable feature regions comprise IR material having an absorption maximum between 800 nm and 1000 nm.
3. The safety device according to claim 1, characterized in that: Only one of the machine-readable characteristic regions comprises an IR substance having an absorption maximum between 800 nm and 1000 nm and the other of the machine-readable characteristic regions comprises an IR substance having no absorption maximum between 800 nm and 1000 nm.
4. The safety device according to at least one of claims 1 to 3, characterized in that The IR substance present in at least one of the characteristic areas has a significantly higher absorption at a wavelength of 950 nm than at a wavelength of 850 nm, in particular at least 3% higher, at least 5% higher or even at least 8% higher.
5. The safety device according to at least one of claims 1 to 4, characterized in that The IR substance present in at least one of the characteristic regions has a reflection of 60% or less in a wavelength range from 800 nm to 1000 nm.
6. The safety device according to at least one of claims 1 to 5, characterized in that The two machine-readable feature regions overlap each other in the projection at least in some regions.
7. The safety device according to at least one of claims 1 to 6, characterized in that The two machine-readable characteristic regions in each case form a machine-readable secret code, preferably the two machine-readable characteristic regions together form an additional machine-readable secret code.
8. Safety device according to at least one of claims 1 to 7, characterized in that The two machine-readable feature areas are in each case present consecutively on the foil carrier.
9. The safety device according to at least one of claims 1 to 8, characterized in that One or two of the machine-readable feature regions are structured and presented in the form of patterns, characters or codes.
10. The safety device according to at least one of claims 1 to 9, characterized in that One of the machine readable feature areas is covered by the paper web or the IR barrier in some areas.
11. The safety device according to at least one of claims 1 to 10, characterized in that The safety device is a safety element, in particular a safety wire or a safety belt.
12. Safety device according to at least one of claims 1 to 10, characterized in that The security device is a valuable document, in particular a banknote.
13. A valuable document having a security device according to claim 11, the valuable document being in particular a banknote.
14. A method for testing a safety device according to any one of claims 1 to 12, wherein: The security device is illuminated with IR radiation, the IR radiation reflected by the security device is measured as an IR signal, and from the measured IR signal it is determined whether the security device comprises a characteristic area having an IR absorbing substance having an absorption maximum between 800 nm and 1000 nm.