WO2012045567A1 - Method for reading a value and/or security document - Google Patents

Abstract

In order to be able to verify, using simple means, the authenticity of a value and/or security document by means of a security feature that is not easily detectable by a user, so that the presence thereof is not normally expected, the invention relates to a method for reading a value and/or security document comprising at least one document layer comprising a first polymer. According to the method, a second polymer different from the first polymer is present in or on at least one document layer of the document. According to the invention, the method comprises the following method step: reading the document by detecting the presence of at least the second polymer by spectral analysis in the infrared range.

Description

 Method for detecting a value and / or security document

Description: The present invention relates to a method for detecting a value and / or security document, which comprises at least one document layer.

Such documents are known: they are typically

Identification documents, such as a passport or identity card, which generally consist, at least in part, of a multilayer plastic laminate. Such documents are known, for example, from DE 10 2008 008 044 A1. Thereafter, card-shaped data carriers, in particular security and / or value documents, for example by lamination of several individual layers

(-foils) or be executed in one layer. The material of

Single layers may be, for example, polycarbonate (PC), polyurethane-based thermoplastic (TPU), ABS, polyethylene terephthalate (PET), polyethylene, a composite of PC and TPU or paper, paperboard or fabric or a composite of individual ones of these materials. The core of the cards may for example consist of a light-absorbing material, while the Au ßenlagen consist of a transparent material.

Other security and / or security documents are, for example, the driver's license, a check or credit card, a company card, authorization card or

Membership card, which is generally provided in the form of a card in ID-1 format, also laminated and made of plastic. Also, banknotes, checks, gift and shopping vouchers can at least partly

Plastics exist. The documents mentioned each consist of at least one document layer and usually more than one document layer. At least some of the document layers of said ID-1 cards are made wholly or at least partly of plastics.

Furthermore, it is known from DE 10 2007 052 947 A1 to produce a value and / or security document which has at least one polycarbonate layer of a material based on bisphenol A and an inkjet printing layer arranged thereon. The ink jet printing layer contains, inter alia, a binder with a Polycarbonate derivative based on a geminal disubstituted

Dihydroxydiphenylcycloalkane, for example based on 4,4 '- (3,3,5-trimethylcyclohexane-1,1-diyl) diphenol, 4,4' - (3,3-dimethylcyclohexane-1,1-diyl) diphenol or 4, 4 '- (2,4,4-trimethylcyclopentane-1,1-diyl) diphenol.

Security features are used to verify the authenticity of these documents. When

Security features are, for example, in DE 10 2007 015 934 A1 guilloches, microchip, metameric systems, imprints with fluorescence, phosphorescence and / or upconversion colors, barcodes, optically variable colors, holograms and kinegrams, digital watermarks, register prints, see-through windows, Melierfasern, security threads and micro perforations called. In addition, imprints with infrared color are given as a security feature. For example, it is in the

Security feature in this document in one embodiment to a non-solid print in a color that absorbs infrared light, but transmits visible light.

Furthermore, DE 10 2005 032 704 A1 specifies a sheet-shaped value document which has a machine-readable code, which is formed in particular in the form of a barcode. The barcode can be detectable, for example, in the infrared spectral range. For this purpose, the barcodes can be made of IR-absorbing and luminescent

Feature substances. An infrared-absorbing tracer may be substantially colorless in the visible spectral region.

The present invention has for its object to provide a method for detecting a value and / or security document that is particularly suitable to verify the authenticity of the document. Above all, the security feature should not be immediately recognizable, so that its presence is usually not expected. In addition, the verification should be possible with simple means. The object is achieved by the method for detecting, in particular verifying the authenticity, of a value and / or security document comprising at least one document layer containing a first polymer. According to the present invention, a second polymer other than the first polymer is present in or on at least one document layer. According to the invention, the method comprises the following method step: detecting the document by detecting the presence at least the second polymer by spectral analysis in the infrared range. This does not exclude that for practical reasons, for example, to increase the security of the verification, in addition, the presence of the first polymer by spectral analysis in the infrared range is detected.

If in the description of the present invention and in the claims the terms "polymer", "first polymer", "second polymer", "other polymers" etc.

which include not only pure polymers, including copolymers, but also polymer combinations, for example blends (physical

Polymer blends) to understand. Thus, the second polymer of the first polymer may inter alia also differ by a polymer component additionally contained in the second polymer, which is not contained in the first polymer. If the two polymers are otherwise identical, the difference is caused solely by this further blended polymer component.

Preferably, the first and second polymers and optionally any further polymer are visually indistinguishable from each other, i. possible additives, such as

Dyes are added to both / all polymers equally. The infrared range used for the spectral analysis (wavelength: 800 nm to 1 mm) is in particular the middle infrared range in which vibration modes of the polymers can be detected, ie, modes in the range of, for example, 4000 cm ^-1

(Wavelength: 2.5 μm) to 400 cm ^-1 (wavelength: 25 μm) These vibration modes are primarily vibration modes which detect individual bonds (localized vibrations) as well as scaffold vibration modes In addition, it is also possible to evaluate harmonics and combination oscillations In principle, other infrared ranges can also be used, provided that differences in the spectral characteristics of the two polymers (luminescence, absorption) are evident in these other regions.

According to a preferred embodiment of the invention, the presence of the second polymer is detected by detecting the presence of an IR band characteristic of the second polymer, in particular IR absorption band. By taking advantage of the fact that a genuine document contains at least two different polymers which have different IR spectra, while in comparable documents only the first polymer is used, it can be determined by simple means of IR spectroscopy whether an examined

Document actually contains these two polymers. For this purpose, it is not necessary for the first polymer also to be detected spectrally, for example because the presence of the usually used first polymer in the document is normally expected anyway. For the verification of the authenticity of the document, the detection of the IR properties of the additionally introduced second polymer is therefore fundamentally first according to the invention. Visually and without additional aids, it is not evident whether a document contains the second polymer in addition to the first polymer. Therefore, the authenticity of such a complex composed document can not be verified without these aids and only visually. Thus, however, the presence of the second polymer in addition to the first polymer in the document is not apparent, so that a construction of a document with two

different polymers can be used as a security feature. Such a structure is not recognizable as such to a user. The

security feature according to the invention is thus a so-called "second level" - or even "third level" security feature that on the one hand already in one

Comparable document usually existing materials (first polymer) and on the other hand from materials that are only slightly changed compared to the existing materials in the document (second polymer) exists. The

Security feature is therefore neither visible nor forfeitable, but can be detected with a suitable device.

It is advantageous that IR spectroscopic methods have long been established.

In particular, the identification of substances by means of absorption spectroscopy in the infrared range is an everyday practice in chemical laboratory operation. Therefore, the

conditions for a sufficiently safe and robust use of this technique in routine operation given. This technique is inexpensive, providing a cost-effective solution for verifying the document.

In addition to the aforementioned method for detecting the document, a value and / or security document according to the invention, which is at least one of a first polymer document layer containing, in or on at least one

Document position of the document is a different from the first polymer second polymer and the two polymers have different IR absorption spectra, in particular different vibration spectra.

For detecting the document and in particular for determining the presence of one or more characteristic IR bands of at least the second polymer in the document, suitable detection devices can be used for this purpose. These are also within the meaning of the present application according to the invention. They are capable of differentiating the two polymers in the document by means of infrared spectral analysis.

The detection device may for example be constructed on the basis of a Fourier transform infrared spectrometer (FTIR) or on the basis of a Raman spectrometer and be arranged to be in transmission or reflection, for example ATR

(attenuated total reflection). In the case of an FTIR spectrometer arrangement, such a device comprises in particular an infrared radiation source which is capable of emitting the infrared radiation required for the detection. Preferably, this radiation source can emit infrared radiation in the mid-infrared spectral range. As a radiation source, for example, a globar can be used. Basically, the emission spectrum of the

 Radiation source to adapt to the area in which the differences in the infrared absorption of the first polymer and the second polymer manifest. Furthermore, the detection device comprises an infrared sensor, for example a photodiode, a thermal or pyroelectric detector. Continue

typically uses an optical arrangement based on an interferometer, which additionally has a suitable support for the document to be examined.

For a Raman arrangement, in particular a laser light source as

Radiation source and a high-resolution monochromator as a dispersive element and a photomultiplier used for detection. Also in this case, the optical arrangement must have a holder for the document to be examined.

The FTIR measuring device is preferably used when the document layer to be examined, in or on which the second polymer is located, is within one Range of a few μηι, for example, up to 10 μηι, located below the surface of the document, since the IR radiation used for the investigation can not escape from a greater depth and the detection is therefore limited to the surface area. In contrast, the second polymer is in or on one

Document layer, which is at a greater distance, for example, more than 10 μηι, below the surface, i. inside the document is located, the Raman measuring arrangement is chosen, which works with visible light, so that the

Excitation radiation and the radiation also scattered in the visible spectral range can pass through one or more other document layers. Thereby, the information about the presence of the second polymer can also be obtained from inside the document.

For example, for the document capture, the entire surface of the

Document of the radiation or, alternatively, only a part of the surface, so that information about the identity of this subarea is detected only with respect to that part of the surface of the document. The measuring arrangement can be in

Transmission or by superficial absorption and scattering of the unabsorbed light work. In principle, it is also possible that a pattern is detected spatially resolved, which has been generated with the second polymer, so that the additional

Information encoded in this pattern can be detected. For this purpose, an imaging optics may be provided, or the pattern is detected by means of a scanning technique, such as the laser beam of the required for the Raman spectrometer laser light source, for example, line by line over the surface containing the pattern and thereby sequentially obtained signal sequence are converted into an image.

Examples of the value and / or security documents according to the invention are

Passports, identity cards, driving licenses, vehicle registration documents, vehicle registration documents, visa, check cards, credit cards, checks, banknotes, company ID cards,

Credentials, membership cards, gift certificates, shopping vouchers and tokens. It is particularly preferred if the value and / or

Security document conforms to the ID-1 or ID-2 format in accordance with ISO 7810 or the data page of a document in ID-3 format in accordance with ISO 7810. The security and / or security documents according to the invention are usually produced by lamination of films. The slides can be the same or

various materials, in particular polycarbonate (PC), in particular bisphenol A polycarbonate, polyethylene terephthalate (PET), its derivatives, such as glycol modified PET (PETG), polyethylene naphthalate (PEN), polyvinyl chloride (PVC),

 Polyvinyl butyral (PVB), polymethyl methacrylate (PMMA), polyimide (PI), polyvinyl alcohol (PVA), polystyrene (PS), polyvinylphenol (PVP), polypropylene (PP), polyethylene (PE), thermoplastic elastomers (TPE), in particular thermoplastic polyurethane ( TPU), acrylonitrile-butadiene-styrene (ABS), paper, Teslin® and their derivatives, coextruded films containing, inter alia, these materials, as well as

 Hybrid materials containing, among others, the above-mentioned materials.

Particularly preferred are security and / or security documents which at least partially consist of PC and / or PET and / or PE and / or polymers similar thereto. The films are laminated under pressure and heat.

Documents from PC are typically produced at 180 ° C to 210 ° C and at a pressure of more than 5 bar (maximum 20 bar) within 1 s to 1 h. Short cycle times are common for single card lamination, long cycle times for batch lamination of multiple uses. According to a preferred embodiment of the present invention, in addition to the presence of the second polymer, in the method according to the invention, the presence of the first polymer is also detected by spectral analysis in the infrared range. According to a preferred embodiment of the invention, the first polymer and the second polymer each contain a first monomer and a second monomer. The respective first monomers of the first and second polymers are in this

Embodiment identical and the respective second monomers of the first and the second polymer different. Although the two polymers are thus different overall, they also have certain similarities (via the first monomers), so that a user can not perceive the difference visually and without any aids.

Insofar as the term "monomer" is given in the description relating to the invention and in the claims, it includes both those for the preparation, i.

Polymerization, used chemical compounds as well as after Implementation, ie polymerization, structural units contained in the polymer, resulting from their underlying chemical compounds used to understand. In a variant of this embodiment, it is also possible to use first and second polymers, of which at least one, for example the second polymer, consists of three, four, five or even more monomers and wherein only one of the monomers, namely the first monomer, in both polymers is identical. Alternatively, the second monomer in the second polymer may be identical to the second monomer in the first polymer. Alternatively, the first polymer may also consist of more than two monomers, namely three, four, five or even more monomers. In this case, there are several alternative possibilities, namely only the respective first monomer in both polymers is identical, and the respective second, third and further monomers are different, or the first and the respectively second monomer in both polymers are identical, and each third and further monomers

different, etc.

Among others, the following variants result (each first term: first polymer / second term: second polymer, Α, Α ', Β, Β', C, C: first, second, third

Monomer, in addition to the monomer of the second polymer different from the monomer of the second polymer, with up to three monomers in the two polymers):

1) AB / AB ', 2) AB / AB'C, 3) AB / ABC, 4) ABC / AB'C, 5) ABC / ABC.

Of course, many other variants are possible, especially if the polymers are made up of more than three monomers. What is significant in all these variants is that among the respective monomers of the first and second polymers is at least one monomer of the one polymer which is different from the corresponding other monomer of the other polymer. Therefore, every polymer of n ¹ (first polymer) or n ² (second polymer)

Be formed monomers (n ¹ , n ² are integers), wherein at least one of the n ¹ monomers of the first polymer with one of the n ² monomers of the second polymer is identical (identity pairs) and the others are different. Furthermore, it is to be demanded that if several pairs of identical monomers occur between the two polymers, at least one monomer of the two polymers forms no identity pair and these two polymers are thus different. In addition to the first and second polymers, it is also possible to include in the document further polymers which in turn differ from one of the two polymers only in one or a few of the monomers, or which are completely different from the first and the second polymer.

By this selection of at least two different polymers from which or with which the document is formed, it is virtually impossible to distinguish the polymers without any aids. Due to the two different monomers in the polymers, however, these are distinguishable by detection by means of infrared spectroscopy, so that a verification of the authenticity of the document on the

Presence of the second polymer is possible, which is done by means of spectral IR analysis.

According to a particularly preferred embodiment of the present invention, the first polymer and the second polymer are each polyester.

According to a particularly preferred embodiment of the present invention, the first monomer is selected from the group comprising terephthalic acid, isophthalic acid, phthalic acid, their derivatives and phosgene. Terephthalic acid, isophthalic acid, phthalic acid or their derivatives are used together with a diol for the preparation of

Polyphthalates using polyterephthalates using

Terephthalic acid as the first monomer are particularly preferred. Phosgene as the first monomer is used together with a diol to make polycarbonates. The second monomers may be mainly diols. Particular preference is given to diols which are selected from the group comprising 4,4'-dihydroxy-2,2-diphenylpropane, geminally disubstituted dihydroxydiphenylcycloalkanes, derivatives thereof, ethylene diol and 1,4-bis (hydroxyalkyl) cyclohexane, in particular 1, 4-bis (hydroxy (C 1 -C ₄ -alkyl)) cyclohexane and most preferably 1, 4-bis (hydroxymethyl) cyclohexane.

The first polymer may be, for example, polyethylene terephthalate (PET). For its preparation, terephthalic acid or a derivative thereof is used as a first monomer and ethylene diol (HO-CH ₂ CH ₂ -OH) as a second monomer. In order to provide a second polymer which is only slightly different, 1,4-bis (hydroxymethyl) cyclohexane is used instead of ethylene diol as the second monomer. The resulting second polymer is then PETG. Alternatively, the second polymer may also be a copolymer

Terephthalic acid with both ethylenediol and with 1,4-bis (hydroxymethyl) cyclohexane. Depending on the proportion of 1,4-bis (hydroxymethyl) cyclohexane in this copolymer, the resulting second polymer differs to a greater or lesser extent from the first polymer.

Alternatively, the first polymer may be polycarbonate (PC). For its preparation, phosgene is used as the first monomer and bisphenol A (4,4'-dihydroxy-2,2-diphenyl-propane) as the second monomer. In order to provide a second polymer which is only slightly different, instead of bisphenol A, a geminally disubstituted

 Dihydroxydiarylcycloalkane, especially dihydroxydiphenylcycloalkane, used as second monomer. For example, the geminally disubstituted

Dihydroxydiphenylcycloalkane 4,4 '- (cyclohexane-1,1-diyl) diphenol or a derivative thereof, for example 4,4' - (3,3,5-trimethylcyclohexane-1,1-diyl) diphenol, 4,4'- (3,3-Dimethylcyclohexane-1,1-diyl) diphenol or 4,4 '- (2,4,4-trimethylcyclopentan-1,1-diyl) diphenol. Alternative compounds of this type which can be used as the second monomer instead of bisphenol A are described, for example, in DE 10 2007 052 947 A1. The disclosure of all polycarbonates specified therein is expressly incorporated in the present application as being in accordance with the invention. The functional carbonate structural units mentioned in DE 10 2007 052 947 A1 of the formula (I) given there are formed when the diphenols are used there

given formula (Ia). In particular, it is also stated that the

Polycarbonates may further contain other diphenols, for example

Hydroquinone, resorcinol, dihydroxyphenols, bis (hydroxyphenyl) alkanes, 4,4'-dihydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) -propane and other diphenols. For the rest, express reference is made to the variants of the invention disclosed in this document

Polycarbonate derivative with the formal (I) directed. The in this document

The polycarbonate described includes inter alia also the polymer APEC® marketed by Fa. Bayer, DE. Also, this material is expressly incorporated as the second polymer in the disclosure of the present application.

Of course, the second polymer can also be formed with the additional use of bisphenol A, so that, depending on the proportion of bisphenol A in this polymer, IR properties of the second polymer which are more or less similar to those of the first polymer are obtained. According to a further preferred embodiment of the present invention, the first polymer and the second polymer differ in terms of

Degree of crosslinking. This concept of the presence of two only a little

different polymers in the value and / or security document differs from the aforementioned concept in that no different monomers are used for the preparation of the two polymers but only by selecting suitable parameters for the polymerization process the respective

Structural properties of the first and the second polymer are different. Of course, this concept can also be combined with the aforementioned concept that partially different monomers are used to prepare the first and second polymers.

According to a particularly preferred embodiment of this second concept, the first polymer and the second polymer are each polyethylene. For example, the first polymer may be PELD (with highly branched polymer chains) and the second polymer may be PEHD (with lightly branched polymer chains).

Of course, other concepts for providing at least two or more only slightly different polymers for producing a value and / or security document are conceivable, such as polymers with different molecular weight and otherwise preferably the same composition, or polymers with different degrees of crystallinity and otherwise preferably the same

Composition. Furthermore, polymer combinations can be used in which the first and the second polymer are copolymers and the first polymer

For example, a block copolymer and the second polymer are a random copolymer. It is of course essential that in each case differences in the spectral properties, in particular spectral absorption properties, of the respective first and second (and optionally third, fourth and further) polymers in the infrared range show that can be evaluated, whereby not exclusively the middle infrared range must be used, but possibly other areas, provided that they give a suitable difference in the IR properties.

Another way to provide at least two polymers that are different from one another in the document is to provide at least one document layer of a first polymer and at least one second polymer in or on the first Document layer by / ns / fu-modify the first polymer to produce. The second polymer is formed in this case from the first polymer. For this purpose, the first polymer either over the entire surface or only locally limited in or on the first

Document layer by energy input in the presence of additional chemical agents (such as oxygen) or even without such additional agents in a chemically altered species, the second polymer converted. For example, -C (= 0) - groups can be cleaved in a polyester polymer chain by energy input, so that polyether groups (-0-) arise. For example, the energy can be registered in the material of the first polymer by means of a laser over the entire area or over a limited area. Thus, it is also possible to form patterns on the surface of the first document layer. Of course, it is also possible, by introducing energy into the first polymer, to bring about a change in the modification, for example to change the crystallinity of the material. Also contemplated are chemical rearrangements that result in chemically altered species, or even chemical reactions on functional groups that occur in the presence of suitable chemical agents, such as halogenation via gaseous phase halogenating agent (e.g., bromine or iodine) in contact with the first polymer. and under irradiation with UV light. The polymers used can be mixed with other substances to provide suitable dosage forms, such as for forming a film or for producing a printing ink, for example for a print, for example screen printing or

Inkjet printing, or paint for application by other techniques. For example, colorants and fillers for the production of films and colorants, fillers, solvents, Antischaummitel, adjusters, wetting agents, surfactants, flow agents, dryers, catalysts, (light) stabilizers, preservatives, biocides, other organic viscosity adjusting polymers, buffer systems, etc. for Production of a printing ink can be used. According to a preferred embodiment of the present invention, the security and / or security document comprises at least a first document layer and a second document layer, wherein the first document layer at least partially consists of the first polymer and the second document layer at least partially of the second polymer. In particular, the first document layer can essentially consist of the first polymer and the second document layer essentially consist of the second polymer.

For example, the first polymer may form a first document layer of the document and the second polymer may form a second document layer of the document. In this case, the two document layers of the document consist almost completely of the respective polymers. For example, according to a preferred embodiment of the method according to the invention, the document may have an upper outer first

Document layer of the first polymer and a lower outer second

Document layer of the second polymer include.

In principle, the method according to the invention may comprise the following method steps: i) optionally detecting the presence of the first polymer of the first document layer and ii) detecting the presence of the second polymer of the second document layer, wherein the first document layer is preferably the upper outer document layer and the second document layer is preferably the second document layer lower outer document layer.

Alternatively, the first polymer may form a first document layer of the document and the second polymer may form a pattern printed or otherwise applied to the first document layer, or to any other document-accessible document layer of the document. For example, the pattern using

Screen printing or inkjet printing applied. Once again alternatively, the second polymer in the last-mentioned variant can form a pattern made in the first document layer or the other document layer of the document, for example by filling in depressions. Such depressions can

For example, be imprinted.

In addition to the first and second document layers, the document usually contains further document layers, for example outer overlay films, provided the first and second document layers are not on the outside, as well as

optionally a carrier layer and other function-related document layers.

Furthermore, the second polymer may also be used in the preparation of the paper for

Banknotes, for instance in the form of stripes, but also over the entire surface or in the form of other patterns, such as diamonds, wavy lines, guilloches, etc., are applied to the paper web, or the second polymer is applied to the banknote paper directly or as part of a printing ink after papermaking in the production of banknotes. Thus, according to a preferred embodiment of the method according to the invention, a material essentially consisting of the second polymer is in the form of a pattern on or in at least one first document layer or the other document layer consisting essentially of the first polymer.

The information encoded in the pattern may be a value of the document or a

Identification, for example, for the owner. The pattern may be formed by any symbols. For example, the pattern may be a

be one-dimensional or two-dimensional barcode or encode, for example, either in plain text or coded form present signs. Also in this case, the method according to the invention may comprise the following method steps: i) optionally detecting the presence of the first polymer of the first document layer and ii) detecting the presence of the second polymer of the sample. If the pattern is scanned, for example line by line, the code can be read and the information encoded therein can be captured.

In a further embodiment of the invention, the first polymer may form a first document layer and the second polymer may form a localized area at a defined location of the document on or in the first document layer or on or in another document layer of the document limited area completely or only partially, for example in the form of a pattern can fill. Of course, however, this can also be realized in that an entire second document layer consists of the second polymer and can be detected from the outside only in a localized area via a window permeable to the IR detection. For the detection of the presence of the second

In addition, polymers require the area of the document in which the second polymer is or is expected to be examined. In a forgery, the second polymer may optionally be present in a different range and therefore can not be detected by the method according to the invention. Of course, combinations of the variants indicated above can be realized, for example, a first document layer of a first polymer, a second document layer of a second polymer, a in the first

Documents embedded pattern of the second polymer and / or embedded in the second document layer pattern of the first polymer, wherein one of the two patterns or both may additionally be present only at localized locations of the respective document layer and thus more information about the location of the second Deliver polymers. According to a particularly preferred embodiment of the invention

Process is the presence of the first and the second polymer in the

Method steps i), namely detecting the presence of the first polymer, and ii), namely detecting the presence of the second polymer, in each case at least one predetermined spectral position detected. In this case, a first absorption caused by the first polymer and a second absorption caused by the second polymer are determined. In a third method step iii), the first and the second absorption are then determined. The first absorption and the second absorption are preferably compared in a fourth method step iv). For this purpose, the respective attenuation of the radiation is determined in the form of the respective extinction values.

In still another preferred embodiment of the present invention, in step iii) an index is formed, which consists of the first absorption

(Attenuation of the radiation) and the second absorption (attenuation of the radiation) gives, for example, the quotient of the first absorption and the second absorption. This measure indicates whether or not the second polymer is actually present, thus giving the authenticity of the document.

Alternatively, only the absorption of the second polymer in the document can be detected. The presence of the second polymer in this case is indicated by an absorbance in a suitable wavelength range.

Again, alternatively, the shift of an IR band can be detected to determine if the second polymer is present in the document. The figures given below serve to illustrate the invention. They merely illustrate embodiments. They show in detail:

1 shows a schematic representation of a detection device for the

 inventive method;

 2 shows a document having a first document layer of a first polymer which has a barcode printed from a second polymer;

3 shows a comparison of two IR spectra taken with an FTIR

Measuring arrangement.

Elements with the same function are designated in the figures with the same reference numerals.

Fig. 1 shows a detection device based on an FTIR measuring arrangement. The document is designated 1. It is held by a document holder 2. The document holder 2 has an opening at the bottom so that measuring radiation can reach the document 1 from below. A radiation source 4 emits IR radiation in the middle frequency range. This radiation is first passed through a beam splitter 5 via an optical arrangement (Michelson interferometer) and arrives at a stationary mirror 6. At the same time, radiation also reaches the beam splitter 5 on a movable mirror 7. The radiation of both radiation paths is then transmitted through a beam splitter 5 another mirror 8 passed to the document 1. The scattered radiation is detected in the detector 3 and in a downstream evaluation system (not shown). FIG. 2 shows an example of a document 10 having a first document layer 11 made of a first polymer (bisphenol A-based polycarbonate). This document layer is one of several document layers in the document. It is located at the surface of the document. In order to be able to detect the presence of a second polymer in the present case, an FTIR measuring arrangement is used.

On the first document layer 10, a barcode 12 is applied, which with a

Printing ink containing a second polymer, which differs from the first polymer only in terms of the modification of the bisphenol A used. This barcode 12 is virtually invisible to the naked eye because both polymers look identical. The difference between the two polymers can however with the FTIR measuring arrangement are detected. For this purpose, the barcode 12 is scanned line by line, so that on the one hand, the coded in the barcode 12 information can be detected. For this purpose, the fact is exploited that the IR absorption in the area of the barcode strip differs from that between the strips. The other is

According to the invention detects the identity of the two polymers.

By way of example, FIG. 3 shows two IR spectra, the first polymer being designated PC1 and the second polymer PC2. The spectrum of PC1 is recorded at a location of the first document layer 10 where the barcode 1 2 is not printed, and the spectrum of PC2 at the location of the barcode 12.

Both polymers show significant differences in the IR spectrum, it being noted that the spectrum shown here represents only a small portion of the entire IR spectrum of 4000 cm ^"1 to 400 cm ^{" 1} . In the remaining IR spectral range, the two spectra are virtually identical, so that at a

 Verification of the document by means of IR spectroscopy no differences would be found. The intensity plotted on the ordinate is the radiation intensity detected by the detector. PC1 and PC2 are polycarbonate materials based on cyclohexane-modified bisphenol A.

In the wavenumber ranges indicated by the arrows, it can be determined whether the second polymer PC2 is present. For this either measuring points of both polymers can be evaluated, or it is only the measuring point of the barcode 1 2 checked only for the presence of the second polymer. The differences in the measured intensity can be used to determine if the second polymer is present. Upon determination of the intensity of the radiation of both polymers in at least one of the wavenumber ranges indicated here, an intensity quotient Qi (v) can be formed, for example the intensity l which is obtained for the measurement of the first polymer PC1 at a certain wavenumber, above the intensity I _{2 obtained} in the measurement of the second polymer PC2 at the same wavenumber: Qi (v) = Ii / 1 ₂ . Its size is a measure of whether the second polymer is present or not. In order to determine the critical size for verification of the authenticity of a document containing the polymer PC2 in the form of the barcode, the corresponding Determined spectra on real documents and thus reference quotients formed. The value for Qi (v) must in any case be different from 1 in the real document, because if Qi (v) = 1, it means that the material of the barcode matches that of the rest

Document location is identical.

Claims

Method for detecting a value and / or security document comprising at least one document layer containing a first polymer, wherein a second polymer other than the first polymer is located in or on at least one document layer, characterized in that the method comprises the following method step Detecting the document by detecting the presence of at least the second polymer by spectral analysis in the infrared range.  A method according to claim 1, characterized in that the detection of the Document for verifying the authenticity of the document.  Method according to one of the preceding claims, characterized in that the presence of the second polymer is detected by the  Presence of a characteristic of the second polymer IR band is detected.  A method according to claim 3, characterized in that the presence of the characteristic IR band of the second polymer is detected by means of an IR or Raman spectrometer.  Method according to one of the preceding claims, characterized in that the document is detected by detecting the presence of the first polymer and the presence of the second polymer by spectral analysis in the infrared range.  The method of any of the preceding claims, characterized in that the first polymer and the second polymer each contain a first monomer and a second monomer, wherein the respective first monomers of the first and second polymers are identical and the respective second monomers of the first and second Polymers are different. Method according to one of the preceding claims, characterized in that the first polymer and the second polymer are each polyester. Method according to one of the preceding claims, characterized in that the first monomer is selected from the group comprising Terephthalic acid, isophthalic acid, phthalic acid, its derivatives and phosgene. Method according to one of claims 7 and 8, characterized in that the second monomers are diols. 10. The method according to any one of claims 7 - 9, characterized in that the second monomers are selected from the group comprising 4,4'-dihydroxy-2,2-diphenyl-propane, geminally disubstituted Dihydroxydiphenylcycloalkane, their derivatives, ethylene diol and 1 , 4-bis (hydroxyalkyl) cyclohexane.  1 1. A method according to claim 10, characterized in that the geminal  disubstituted dihydroxydiphenylcycloalkane is 4,4 '- (cyclohexane-1,1-diyl) diphenol or its derivative.  12. The method according to any one of the preceding claims, characterized in that the first polymer and the second polymer in terms of  Degree of differentiation.  13. The method according to claim 12, characterized in that the first polymer and the second polymer are each polyethylene.  14. The method according to any one of the preceding claims, characterized in that the document comprises at least a first document layer and a second document layer and that the first document layer at least partially from the first polymer and the second document layer at least partially made of the second polymer.  15. The method according to any one of the preceding claims, characterized in that there is on or in at least one essentially consisting of the first polymer document layer consisting essentially of the second polymer material in the form of a pattern.  16. The method according to any one of the preceding claims, characterized in that the document is an upper outer first document layer of the first polymer and a lower outer second document layer of the second  Polymer, and that the method comprises the steps of: i) detecting the presence of the first polymer of the upper outer first document layer and ii) detecting the presence of the second polymer of the lower outer second document layer. 17. The method according to claim 16, characterized in that the presence of the first and the second polymer in the process steps i) and ii) is detected in each case at least one predetermined spectral position, wherein caused by the first polymer first absorption and by the second polymer induced second absorption and iii) comparing the first and the second absorption. A method according to claim 17, characterized in that in step iii) a quotient of the first absorption and the second absorption is formed.