DE10322794B4 - Sensor for authenticating a luminescent security element of a value document, value document and method for producing a value document - Google Patents

Abstract

Value document (4) with at least one security element (2) designed for authenticity recognition, the security element (2) having a marking layer (18) with a luminescent anti-Stokes phosphor (20) with an excitation wavelength between 940 in a marking area (14) nm to 990 nm excitable anti-Stokes pigments which emit in a luminescence response with a response wavelength at 800 nm +/- 10 nm, characterized in that the marking layer (18) is formed by a body (16, 40) is, in which the anti-Stokes pigments with particle diameters of less than 5 μm are embedded in a matrix and in lateral subregions of the marking layer (18) radiation absorbers which can absorb emission radiation of an anti-Stokes phosphor by selective irradiation with a Lasers with a wavelength of 1064 nm are generated, and those of a NIR for wavelengths of more than 780 nm and less than 1200 nm transparent top layer is covered.

Description

The invention relates to a document of value having at least one security element designed for authentication, in particular by a sensor, and to a method for producing such a document according to the preamble of claim. In particular, the sensor is for authenticating a luminescent security element of the value document, comprising an emitter for generating a scanning signal having an excitation wavelength and a radiation receiver for detecting a response signal emitted by the security element with a response wavelength.

To protect against counterfeiting or counterfeiting value or security documents, such as banknotes, identity cards or smart cards, provided with so-called security features or security elements that should exclude for example in paper-shaped documents of value, inter alia, an imitation by making color copies safely. The security elements can be designed in particular as optically variable elements, such as holograms or interference layer elements, which convey different color impressions when viewed depending on the viewing angle, but are not transferred to the copy during the copying process. However, such security elements are difficult or impossible to machine-read or evaluate, so that an automated security check of the respective value documents is possible only conditionally and with great technical effort.

Especially in the design of a value document as a data carrier, such as an identification card, credit card, passport, driver's license or the like, however, in addition to a visually recognizable authenticity check and the possibility for automatic authenticity checking with high security against counterfeiting of particular importance. For this purpose it is for example from the DE 101 13 266 A1 and from the DE 101 13267 A1 known to use luminescent anti-Stokes pigments in a security element of a value document. Advantageous compositions of such pigments as well as excitation and emission wavelengths are in the DE 102 03 397 A1 disclosed in the priority of this application and relevant only to novelty.

When using such anti-Stokes pigments via a suitable sensor, the irradiation of a scanning signal generated by an emitter, in particular a laser, in the marking area in which the anti-Stokes pigments are provided. In response to the irradiated scanning signal, the anti-Stokes pigments emit in the so-called "up-conversion-mode" a response signal with a shorter compared to the excitation wavelength response wavelength, which is detected in a suitably designed radiation receiver. The excitability of the anti-Stokes pigments is dependent on the radiated excitation wavelength, wherein also the emitted response wavelength is characteristic of the material properties of the anti-Stokes pigment used, in particular for its activator and codoping with respect to the host lattice used. By evaluating the emitted response wavelength compared to the irradiated excitation wavelength, possibly with additional evaluation of the waveform of the radiated response signal, therefore, a comparatively reliable assignment of the signature of the response signal to expected for certain anti-Stokes pigments signatures is possible. If the detected signature corresponds to an expected signature, it is therefore possible to deduce the expected presence of a certain group of anti-Stokes pigments and, moreover, the authenticity of the value document provided with such a luminescent security feature. Advantageous approaches to this are in the US 2002/0130303 A1 and US 2002/0130304 A1 disclosed.

For use in the authentication of value documents with such luminescent security elements are from the EP 1170707 A2 and the EP 1160719 A2 known sensors particularly suitable. Such sensors include an emitter for generating the scanning signal and a radiation receiver for detecting the response signal and may be statically-stationary or mobile designed as a hand-held sensor. With a sensor of the type mentioned above, a particularly high detection sensitivity and accuracy should be achievable in the authenticity check of the value document.

The object of the invention is to provide a value document which is particularly suitable for authentication of authenticity, in particular by means of such a sensor, and to a method for producing the value document.

With regard to the sensor, the emitter is advantageously designed for generating the scanning signal with an excitation wavelength of about 940 nm to 990 nm and the radiation receiver for detecting the response signal with a response wavelength of about 800 +/- 10 nm.

With regard to the value document, the object is achieved by a value document of claim 1 solved. With respect to the method, the object is achieved by a method of claim 24. The invention is based on the consideration that for a particularly high detection sensitivity, the evaluation of the luminescence properties of the security element should be targeted specifically to a particularly high achievable signal intensity of the anti-Stokes pigments. Especially with regard to the type classes of anti-Stokes pigments which are particularly suitable for use in value documents, it has surprisingly been found that the actually invisible anti-Stokes band located in the near infrared (NIR) region is particularly high compared to the Emission in the visible range has about 100 to 500-fold excessive luminescence intensity. Through a targeted use of this anti-Stokes luminescence, therefore, a signal quality that can be well and reliably evaluated is achievable even with relatively small admixtures of the anti-Stokes pigments in the marking region of a value document. The sensor is thus designed specifically for the evaluation of this NIR luminescence.

As has also surprisingly been found, a controlled variation of the activator concentration and the codoping concentration in the anti-Stokes pigment can be used to influence the onset and decay behavior of the respective luminescences. By evaluating the onset and decay behavior of luminescence, a more in-depth conclusion to the exact composition of the anti-Stokes pigments used is thus made possible. In order to make this also usable for the authenticity check in the sense of a large number of different kinds of conceivable types of pigment, the radiation receiver of the sensor is advantageously designed for detecting a start-up time and / or a decay time of the response signal.

Advantageously, the sensor is integrated in a stationary card reader or designed as a mobile and / or body-worn reading device.

According to the invention, the security element of the value document in a marking area comprises a luminescent marking layer comprising anti-Stokes phosphor which is covered by an NIR-transparent cover layer. According to the invention, the anti-Stokes phosphor is present in the form of anti-Stokes pigments with a particle diameter of less than 5 μm.

It is intended to specifically align the value document in its entirety to a common use with the sensor for authentication. Thus, there should be a marking layer comprising anti-Stokes pigments which can be excited by the excitation wavelength of the sensor and which emit in their luminescent response at the intended response wavelength. In order to protect the anti-Stokes pigments held in the marking layer for high document security but also against external influences and in particular against manipulation, the marking layer should be covered by a cover layer in the manner of a hidden, encapsulated or protected embodiment. The targeted evaluation of the Luminezsenzerscheinungen in the NIR range remains unimpeded by the cover layer for radiation in the near infrared, d. H. is kept transparent according to the invention for wavelengths of more than 780 nm and less than 1200 nm.

In a particularly advantageous embodiment, the NIR-transparent cover layer is formed as a print layer, as a film or as an opaque layer. In an alternative advantageous embodiment, the NIR-transparent cover layer is designed as an opaque substrate with a thickness of more than 20 .mu.m, preferably more than 50 .mu.m.

In a particularly advantageous embodiment, anti-Stokes pigments used are particularly fine-grained safety pigments which can be processed in all known security printing techniques and adhesion promoter layers as well as in paper bodies and plastic films. For this purpose, the anti-Stokes phosphor is advantageously designed in the form of a rare-earth-activated, preferably thulium-activated and ytterbium-co-doped host lattice. In particular, gadolinium oxysulfide (Gd0 ₂ S), yttrium oxysulfide (Y0 ₂ S), lanthanum oxysulfide (La0 ₂ S) and / or lutetium oxysulfide (Lu0 ₂ S) are suitable as host lattice or matrix material. Such anti-Stokes pigments can be incorporated in a very small amount of both a single ink in the visible subject as well as be executed as a separate, invisible machine-readable printing features, such as bar codes or 2D codes or symbols, diagrams, patterns or letter numbers Combinations for, for example, an OCR reader and the like readers.

Although the said anti-Stokes pigments also have anti-Stokes bands in the visually visible range, in particular between 460 and 490 nm and between 630 and 670 nm and between 680 and 720 nm, which, however, are substantially less intense than those now for evaluation provided anti-Stokes luminescence in the NIR range. The security features produced with such anti-Stokes pigments can be used in very fine particle size distribution of a few micrometers in size and are invisible to whitish, depending on the degree of filling in preferably internal printing structures. Especially in the absence of the use of the emission in the visible wavelength range in the authenticity test, such an anti- Stokes pigment are also used internally in documents, for the evaluability is only to ensure that the surrounding layers are kept NIR transparent. Such anti-Stokes pigments can thus be arranged completely invisible on the document of value for printing or areal to full surface for the human eye.

In order to ensure a high read-out speed during the authenticity check and, on the other hand, also to ensure authenticity checking differentiated by differentiated pigments by targeted setting of the decay or decarbelling behavior, the anti-Stokes pigment advantageously has an ytterbium content of 0.05 ≦ x ≦ 0. 80, preferably from 0.20 ≦ x ≦ 0.60, and a rare earth content of 0.0001 ≦ Y ≦ 0.10, preferably from 0.0001 ≦ Y ≦ 0.05. For targeted influencing the arrival and Abklingcharakteristik the anti-Stokes pigment also more cation and / or anions can be incorporated into the host lattice. By a suitable choice of the concentrations, it can be achieved, in particular, that the decay time can be set in a range from 1 to 200 μs and in particular from 10 to 50 μs.

In a particularly advantageous embodiment, the value document is particularly suitable for printing production methods. In order to allow the incorporation of the anti-Stokes pigment in the security element in a particularly simple manner, preferably via a conventional printing method, the anti-Stokes pigment according to the invention has an average particle size of less than 5 microns, in a particularly advantageous embodiment less than 3 μm, in particular less than 2 μm. The anti-Stokes pigments are advantageously incorporated in the form of small inorganic particles in a printing ink, wherein the degree of filling in the range of 1 to 30 weight percent, advantageously in the range of 1 to 20 weight percent and preferably in the range of 5 to 10 weight percent so that the graphic and in particular color design is not disturbed.

The document of value can be designed, in particular in the form of a data carrier, as so-called ID card, passport, visa, driving license card, credit card, postage stamp, coupon, general stamp, banknote or the like, with authenticity being checked with high reliability at speeds of up to 10 m / m. s is feasible. The security element with the luminescent anti-Stokes pigments is further in a particularly advantageous embodiment in a form invisible to the human eye as a machine-readable encoding in the form of individual or constant codes in the form of bar codes, 2-D codes, digit number Symbol elements or the like mounted in the disk, the authenticity detection with the sensor and its evaluation takes place such that the code by means of a secret and arranged in the evaluation algorithm in the form of a software module or preferably in the form of an electronic module and / or in an external evaluation in conjunction with another information element on the disk can be verified for authenticity, with information elements such as magnetic stripe, bar codes, EAN codes and the like printing codes or contact-based and / or contactless chip cards or RFID elements in the form of ROM Speicherele menten with unique IC serial numbers of, for example, some 10 bits to 128 bit length against counterfeiting and / or copying are secured.

As has been found, the luminescence provided for evaluation in the NIR range can be used in a particularly favorable manner by laminating the marking layer comprising the luminescent anti-Stokes pigments into a surrounding layer system. The document of value therefore advantageously comprises a carrier body, which is designed as a basic body for the formation of a value or ID card, in which the marking layer is laminated. The marking layer is advantageously covered by a plurality of NIR-transparent cover layers to form a laminate body.

Advantageously, the marking layer is formed by an extruded or injection-molded plastic body, in which the anti-Stokes pigments are embedded in a matrix. In this case, at least one, preferably both, surfaces of the substrate or the core layer comprising the marking layer with a graphic design and optionally with. be provided an upper cover laminate and / or a lower cover laminate.

With regard to the method for producing the value document, the stated object is achieved by applying the marking layer by means of a coating method such as brushing, spraying, spraying, coating, dipping, but preferably by means of a printing method, preferably by screen printing, intaglio printing, offset printing, statistical printing, screenprinting or letterpress printing, is applied to the carrier body. This allows a comparatively simple production of the security document equipped with the value document, wherein in addition a particularly high flexibility in a possibly desired graphical embodiment of the marking layer, for example as a print image, can be achieved. Furthermore, gravure gravure printing, steel intaglio printing, flexographic printing, digital printing in the form of inkjet printing and / or liquid and solid toner or the Application via the adhesive layer of a thermal transfer and / or Thermosublimationsbandes into consideration. A particularly simple processability is achievable bar by advantageously an ink is used in applying the marking layer, in addition to the anti-Stokes pigments, a solvent and / or a binder is included.

In order to further increase the security function of the security element, the specification of a lateral structure in the marking layer can be provided, so that a distinction can be made between spatially resolved active and non-active regions in the evaluation of the luminescence phenomena. In order to make this possible, radiation absorbers are produced according to the invention in lateral partial regions of the marking layer by selective irradiation with a laser, preferably with an ND: YAG laser with a wavelength of 1064 nm. In particular, soot particles which absorb the emission radiation of the anti-Stokes phosphors can be generated by the laser irradiation, so that no emission is registered from the outside in these areas.

The advantages achieved by the invention are, in particular, that a particularly high signal intensity can be achieved by the targeted use of the luminescence phenomena of the anti-Stokes pigments in the NIR range, so that a reliable detection of the pigments in the authenticity check even with only comparatively low pigment concentrations can be reached in the marking layer. The luminescence security feature is also largely invisible in the visible wavelength range, but activatable and verifiable by means of infrared radiation, so that the authenticity check is particularly suitable for a machine evaluation. A replica of the security element is thus due to the hidden arrangement of the security element not or only with considerable effort even conceivable. The targeted influencing of the Ankling- and Abklingverhaltens the anti-Stokes luminescence also makes it possible to increase the available variety of anti-Stokes pigments very strong, so that a replica or counterfeiting are considerably more difficult.

An embodiment of the invention will be explained in more detail with reference to a drawing. Show:

1 1 schematically a sensor for authenticating a luminescent security element in an associated value document,

2 an alternative embodiment of the value document after 1 .

3 to 6 schematically each the construction of further alternative embodiments of the value document according to 1 and

7 the value document 1 in supervision.

Identical parts are provided with the same reference numerals in all figures.

The in 1 only schematically shown sensor 1 is for the authenticity detection of a luminescent security element 2 an associated value document 4 designed. The sensor 1 can be configured as a stationarily installed or transportable sensor and in particular with regard to its functional components the same or similar to those from the publications EP 1160719 A2 and EP 1170707 A2 , the disclosure of which is hereby fully incorporated, known sensors are configured. As essential functional components includes the sensor 1 to 1 an emitter 6 for generating one by the arrow 8th symbolized scanning signal and one for detecting one by the arrow 10 symbolized by the security element 2 emitted response signal designed radiation receiver 12 ,

The security element 2 of the value document 4 includes in a marking area 14 one on a carrier body 16 applied marking layer 18 containing as active components for authenticity testing luminescent anti-Stokes pigments 20 includes. The marking layer 18 from a topcoat 22 covered.

For the purpose of authentication, the emitter emits 6 of the sensor 1 a scanning signal having a predetermined excitation wavelength into which the anti-Stokes pigments 20 comprehensive marking layer 18 one. The scanning signal causes the anti-Stokes pigments 20 excited to luminescence and emit by means of up-conversion a response signal whose response wavelength is smaller than the excitation wavelength. The radiation receiver 12 detects the emitted response signal, wherein in particular a time-resolved evaluation can be provided. On the basis of the characteristics of the response signal, in particular on the basis of a comparison of the response wavelength with the emitted excitation wavelength and possibly an analysis of the signal shape, the evaluation provides a conclusion on the type and possibly also the number of anti-Stokes pigments 20 in the marking layer 18 possible. Thus it can be detected whether an expected type of anti-Stokes pigments 20 in the marking layer 18 is present, in which case for authenticity of the value document 4 is recognized.

The sensor 1 and the value document to be used with this 4 are designed for a particularly high reliability in the authenticity test with comparatively simple means. For this purpose, it is provided to carry out both the excitation of the luminescence and the evaluation of the luminescence in wavelength ranges in the NIR (near infrared). To make this possible, the emitter is 6 for generating the scanning signal with an excitation wavelength of about 940 nm to 990 nm and the radiation receiver 12 designed to detect the response signal with a response wavelength of about 800 +/- 10 nm. The adaptation of the radiation receiver in particular can be made possible or facilitated by the selection of suitable detectors and / or, if necessary, by the specification of a suitable optics in the beam path.

In order to enable the consistent use of the luminescent in the NIR range provided in the exemplary embodiment, but also a reliable protection of the marking layer 18 To prevent damage or mechanical damage is the cover layer 22 provided, which is designed by suitable choice of materials NIR-transparent.

The security feature 2 can be designed all over or graphically on the carrier body 16 to be appropriate. Alternatively, the marking layer 18 with the embedded anti-Stokes pigments 20 in the form of a polymer matrix also for adhesion promotion to the cover layer 22 also be used under or on the marking layer 18 a graphic design not shown may be arranged. The carrier body 16 may be formed in particular from plastic or paper.

The anti-Stokes pigments 20 are based on a thulium (Tm) -activated and Ytterbium (Yb) -coded host lattice, as a host lattice gadolinium oxysulfide (Gd ₂ O ₂ S), yttrium oxysulfide (Y ₂ O ₂ S), lanthanum oxysulfide (La ₂ O ₂ S) and / or Lutetiumoxysulfid (Lu ₂ O ₂ S) may be used. The anti-Stokes pigment 20 is thus represented by the formula (Gd _{1 -xy} Yb _x Tm _y ) ₂ O ₂ S or (Gd _1-xy ) ₂ O ₂ S: Yb _x Tm _y , (Y _1-xy Yb _x Tm _y ) ₂ O ₂ S or (Y _1-xy ) ₂ O ₂ S: Yb _× Tm _y , (La _{1 -xy} Yb _× Tm _y ) ₂ O ₂ S or (La _1-xy ) ₂ O ₂ S: Yb _× Tm _y , (Lu _1-xy Yb _x Tm _y ) ₂ O ₂ S or (Lu _1-xy ) ₂ O ₂ S: Yb _x Tm _y describable, wherein to set a detail evaluable Ankling- and Abklingverhaltens in the luminescence concentration values of 0.20 ≤ x ≤ 0.60 for the ytterbium content and from 0.001 ≤ y ≤ 0.05 for the thulium content.

The anti-Stokes pigments 20 are matrix-like in the marking layer 18 arranged. It was used that the anti-Stokes pigments 20 can be produced with comparatively small average particle diameters of, for example, less than 2 μm, and without reducing the intensity of the response at comparatively high temperatures of up to 200 or 300 ° C in a matrix-like manner into the marking layer 18 can be integrated, wherein a polymer matrix can be prepared and thereby extrusion, thin film casting, calendering or injection molding can be used. The anti-Stokes pigments 20 Moreover, they are very good chemically resistant, so that they could also be incorporated into a paper matrix, whereby such opaque paper substrates with matrix-like arranged anti-Stokes pigments 20 and / or be provided with a graphic arrangement or in the form of stripes, dots or generally recurrent patterns and can be used for authentication.

In the embodiment according to 2 schematically is a particularly simple held technical embodiment of the value document 4 shown. As a carrier body 16 In this case, a paper or plastic substrate or another usual in the security industry substrate is used. The flat and / or graphically designed security element 2 is applied by means of printing in the graphic industry usual, but can also be laminated or embossed or otherwise applied in the form of a sheet-like layer-like element. In addition, the cover layer may now be in the form of a graphic design 22 arranged. In the embodiment according to 2 are both the carrier body 16 as well as provided in the form of a graphic design cover layer 22 transparent in the NIR wavelength range, so that an undisturbed authenticity check on the in the marking layer 18 contained anti-Stokes pigments 20 by using the sensor 1 is possible. For example, using common opaque white papers having a grammage of 70 to 120 per square meter, a clear verification could be made.

In 3 are the individual layers of a value document 4 shown as separate segments. In this embodiment shown in cross section, the value document 4 the construction of a laminate-like composite of several layers. The electroluminescent pigments 20 or anti-Stokes phosphors comprising marking layer 18 is part of a substrate that due to its relatively massive design and the carrier body 16 forms. This substrate can be on both sides, each with a graphic design 30 be provided, for example, a printed image or pattern, wherein the respective graphical design 30 in turn, with an upper or lower cover laminate 32 is covered. The deck laminates 32 and the graphic designs 30 are there to form the respective cover layer 22 NIR-transparent executed.

The according to the embodiment according to 3 executed value document 4 For example, it may be used as a simple ID card or as a deposit in a passport and the like, where the marking layer 18 comprehensive carrier body 16 a plastic substrate or a paper substrate may be. The cover laminates 32 For example, thin PET films with internal diffractive diffraction structures and a corresponding adhesion-promoting layer may be used, the cover laminates 32 may be microperforated to further increase the security against counterfeiting. To further increase the safety standard, an ND: YAG laser beam with a wavelength of 1064 nm can be used to code into the marking layer 18 or in the foil 30 be written, wherein laterally selective irradiation of the ND: YAG laser beam lateral portions of the marking layer 18 be deactivated, so that with respect to the Lumineszenzeigenschaften a lateral, also usable as a security feature structure arises.

In the embodiment according to 4 is the value document 4 carried out as a disk in which the electroluminescent pigments 20 in a matrix-like arrangement in the adhesion-promoting layer 34 a transparent hologram 36 are arranged. In this embodiment, therefore, the hologram is used 36 as a cover layer 22 for those through the bonding layer 34 formed marking layer 18 , That's why the hologram is 36 performed transparent in the NIR wavelength range, so that a verification of the luminescence can be done by appropriate irradiation from above. Alternatively, the present in the form of a substrate carrier body 16 NIR-transparent, so that the verification can be done by irradiation from below. The hologram 36 in this case denotes diffractive diffraction structures in the corresponding layer constituent.

In the likewise explosive representation of the embodiment according to 5 is the value document 4 as a typical ID document based on two interconnected paper substrates 38 carried out by means of a primer layer 40 connected to each other. The primer layer 40 serves as a marking layer 18 , wherein the electroluminescent anti-Stokes pigments 20 in the primer layer 40 are integrated. The paper substrates 38 are each on their respective outside with a graphic design 42 provided, for example, with a printed image. The incorporation of anti-Stokes pigments 20 in the primer layer 40 can be done evenly matrix-like or graphically designed, in particular, a coding design can be provided in particular. The graphic design 42 may be provided in a further embodiment with further transparent protective layers.

In this case, customary graphic printing techniques or rollers can coat, curtain pour, spray and squeegee and the like coating technologies be used.

In the embodiment according to 6 is the value document 4 also as a typical ID document based on two interconnected paper substrates 38 carried out with a primer layer 40 interconnected with the anti-Stokes pigments 20 in the primer layer 40 are integrated. Also in this embodiment are the paper substrates 38 on their respective outside, each with a graphic design 42 Mistake. For further protection against external influences and mechanical damage, the layer composite thus formed is provided with a comprehensive transparent cover laminate 44 surround. The cover laminate 44 is kept transparent especially in the NIR wavelength range. Preferably, as a cover laminate 44 a PET film, a PETG film or a PVC, PC, PMMA or the like transparent polymeric film of a typical thickness of for example 10 to 100 microns may be used. The foils can be provided internally with diffractive diffraction structures, whereby it is also ensured in these diffraction structures that the transparency is given in the NIR wavelength range. The cover laminate 44 may be provided in addition to further increase the security against counterfeiting with a micro perforation.

In the embodiment according to 7 is the value document executed in the form of a prepaid card 4 shown in supervision. The value document 4 is basically designed in accordance with the requirements of ISO / IEC 7810. In this case, the value document comprises 4 areas 50 . 52 which are NIR-transparent and possibly also optically transparent. The areas 50 . 52 are therefore particularly suitable for receiving a marking layer with the electroluminescent pigments 20 according to the present concept. The upper edge 54 of the area 50 is at a distance of at least 21 mm from the top edge 56 of the value document 4 arranged away, with the lower edge 58 of the area 50 at least 33 mm from the top edge 56 is removed. The area 52 closes immediately to the lower edge 58 on, with its lower edge 60 at least 44 mm from the top edge 56 is removed. The side edges 62 of the area 52 are each at least 20 mm from the corresponding side edge 64 of the value document 4 arranged.

LIST OF REFERENCE NUMBERS

1

sensor

2

security element

4

value document

6

emitter

8, 10

arrow

12

radiation receiver

14

marking region

16

support body

18

marking layer

20

Anti-Stokes pigments

22

topcoat

30

graphic design

32

Upper or lower cover laminate

34

Bonding layer

36

Transparent hologram

38

paper substrate

40

Bonding layer

42

graphic design

44

overlaminate

50, 52

NIR-transparent area

54

upper edge

56

top edge

58, 60

lower edge

62, 64

side edge

Claims (26)

Value document ( 4 ) with at least one security element designed for authentication ( 2 ), the security element ( 2 ) in a marking area ( 14 ) a marking layer ( 18 ) with a luminescent anti-Stokes phosphor ( 20 ) having anti-Stokes pigments which can be excited by an excitation wavelength between 940 nm to 990 nm and which emit in a luminescence response with a response wavelength at 800 nm +/- 10 nm, characterized in that the marking layer ( 18 ) of a body ( 16 . 40 ), in which the anti-Stokes pigments with particle diameters of less than 5 μm are embedded in a matrix and in lateral partial areas of the marking layer ( 18 ) Radiation absorbers which can absorb emission radiation of an anti-Stokes phosphor are produced by selective irradiation with a laser having a wavelength of 1064 nm, and those of wavelengths greater than 780 nm and less than 1200 nm NIR-transparent cover layer is covered. Value document ( 4 ) according to claim 1, characterized in that the body is formed in the form of a polymer matrix. Value document ( 4 ) according to one of claims 1 or 2, characterized in that the body is formed in the form of a paper matrix. Value document ( 4 ) according to one of claims 1 to 3, characterized in that the body in the form of an adhesion-promoting layer ( 34 ) is formed. Value document ( 4 ) according to one of claims 1 to 4, characterized in that the marking layer ( 18 ) on a carrier body ( 16 ) is applied. Value document ( 4 ) according to one of claims 1 to 4, characterized in that the marking layer ( 18 ) Is part of a substrate having a support body ( 16 ). Value document ( 4 ) according to one of claims 1 to 4, characterized in that the marking layer ( 18 ) in the carrier body ( 16 ) is laminated. Value document ( 4 ) according to claim 7, characterized in that the carrier body ( 16 ) is designed as a basic body for the formation of a value or ID card. Value document ( 4 ) according to one of claims 1 to 8, characterized in that the marking layer ( 18 ) is formed by an extruded, calendered, injection-molded or film-cast plastic body into which the anti-Stokes pigments ( 20 ) are embedded in a matrix. Value document ( 4 ) according to one of claims 1 to 9, characterized in that the marking layer ( 18 ) is covered by a plurality of NIR-transparent cover layers. Value document ( 4 ) according to one of claims 1 to 10, characterized in that the NIR-transparent cover layer is formed as an opaque layer. Value document ( 4 ) according to one of claims 1 to 11, characterized in that the NIR-transparent cover layer ( 50 . 52 ) is designed as an opaque substrate with a thickness of more than 20 microns. Value document ( 4 ) according to claim 12, characterized in that the NIR-transparent cover layer ( 50 . 52 ) is designed as an opaque substrate with a thickness of more than 50 microns. Value document ( 4 ) according to one of claims 1 to 13, wherein the NIR-transparent cover layer is formed as an adhesive layer or as a film. Value document ( 4 ) according to one of claims 1 to 13, characterized in that the NIR-transparent cover layer ( 22 ) in the form of a hologram ( 36 ) is formed. Value document ( 4 ) according to one of claims 1 to 13, characterized in that the NIR-transparent cover layer ( 22 ) in the form of a paper substrate ( 38 ) with graphic design ( 42 ) is formed. Value document ( 4 ) according to one of claims 1 to 16, characterized in that a layer composite of the value document ( 4 ) with the NIR-transparent cover layer ( 22 ) in the form of a comprehensive transparent cover laminate ( 44 ) is surrounded. Value document ( 4 ) according to one of claims 1 to 17, wherein the anti-Stoke phosphor rare earth-activated Lanthanoidenoxysulfid of the formula (LN _1-xy ) ₂ 0 ₂ S: Yb _x SE _y with LN = La, Lu, Gd, Y and SE = TM, Er, Ho. Value document ( 4 ) according to claim 18, wherein the anti-Stokes phosphor has an ytterbium content of 0.05 ≤ x ≤ 0.80, preferably 0.20 ≤ x ≤ 0.60, and a Steltenerd ratio of 0.0001 ≤ Y ≤ 0.10, preferably from 0.0001 ≦ Y ≦ 0.05. Value document ( 4 ) according to any one of claims 1 to 19, in which the anti-Stokes pigments ( 20 ) have an average particle size of less than 3 microns. Value document ( 4 ) according to claim 20, in which the anti-Stokes pigments ( 20 ) have an average particle size of less than 2 microns. Value document ( 4 ) according to one of claims 1 to 21, characterized in that radiation absorbers are produced with a Nd: YAG bearing. Value document ( 4 ) according to one of claims 1 to 22, characterized in that radiation absorbers are produced in the form of soot particles. Method for producing a value document ( 4 ) with at least one security element designed for authentication ( 2 ), in which the security element ( 2 ) in a marking area ( 14 ) with a marking layer ( 18 ) coated with a luminescent anti-Stokes phosphor ( 20 ) with anti-Stokes pigments which can be excited by an excitation wavelength between 940 nm to 990 nm and emit in a luminescence response with a response wavelength at 800 nm +/- 10 nm, characterized in that the marking layer ( 18 ) is formed by a body in which anti-Stokes pigments are incorporated into a matrix, wherein anti-Stokes pigments ( 20 ) are produced with particle diameters of less than 5 microns and at temperatures of up to 200 ° C or 300 ° C in the matrix of the marking layer ( 18 ) and wherein in lateral partial areas of the marking layer ( 18 ) are generated by selective irradiation with a laser having a wavelength of 1064 nm radiation absorber, which can absorb an emission radiation of an anti-Stokes phosphor, and the marking layer ( 18 ) of an NIR-transparent covering layer (more than 780 nm and less than 1200 nm) ( 22 ) is covered. The method of claim 24, wherein a polymer matrix is produced using extrusion, thin film casting, calendering or injection molding. The method of claim 24 or 25, wherein the laser is a Nd: YAG laser.

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