WO2009021737A1

WO2009021737A1 - Coloured security document individualization

Info

Publication number: WO2009021737A1
Application number: PCT/EP2008/006695
Authority: WO
Inventors: Malte Pflughoefft; Oliver Muth; Andreas Hoppe
Original assignee: Bundesdruckerei Gmbh
Priority date: 2007-08-10
Filing date: 2008-08-08
Publication date: 2009-02-19
Also published as: DE102007037981A1; PL2183116T3; PT2183116E; RU2010108251A; CN101772421B; RU2506167C2; CN101772421A; EP2183116B1; ES2452295T3; EP2183116A1

Abstract

The invention relates to a method and a device (41) for the coloured individualization of security documents (42) and to security documents (42) having a document body (43) for coloured individualization. In the case of such a document body (43), starting materials are kept inside it, which starting materials can be excited by means of a localized energy input in a targeted manner for formation of nanoparticles (21; 49) of different shapes and/or different local concentrations, wherein a colour impression of the nanoparticles is dependent on their shape and/or their concentration. For the individualization of a security document (42) having such a document body (43), energy is locally introduced in a targeted manner at a location at which a coloured colour impression is intended to be brought about in the document body (43), in order to store an individualizing information item about the colour impression brought about. The device (41) for individualization comprises an energy source by means of which energy can be introduced in a targeted manner into the document body (43) in a controlled manner.

Description

Colored security document customization

The invention relates to a method and a device for colored individualization of security documents that comprise a document body, as well as security documents for color customization with a document body and a method for the production thereof.

Security documents are documents that are protected against counterfeiting, falsification and / or duplication with the help of security elements. Security documents thus include, for example, identity cards, passports, ID cards, access control cards, tax stamps, tickets, driver's licenses, motor vehicle papers, banknotes, checks, postage stamps, credit cards, any smart cards and adhesive labels (for example for product security). Such security documents, which are sometimes referred to as Wertdokumenie, typically have a substrate, a printing layer and optionally a transparent cover layer. A substrate is a support structure to which the print layer is applied with information, images, patterns, and the like. Suitable materials for a substrate are all customary materials based on paper and / or plastic in question.

Many modern security documents comprise a document body comprising at least one, preferably a plurality of, most preferably only a plurality of interconnected layers made of plastics. This document body has one or more security elements. One type of security element is individualizing information introduced into such a card body, such as a serial number, a card number, personal data, for example name and / or date of birth, biometric data, for example pictures (passport pictures), size and / or eye color, etc . may include.

From the prior art it is known to introduce such individualizing information inside the document body consisting of plastic materials. For this purpose, energy is introduced into the plastic material via a laser and this causes a pyrolysis, which leads to a carbonization and thus blackening leads to the places where energy is introduced into the plastics. Such a method is described, for example, in EP 0 975 148 A1. The attachment of the individualizing information inside the document body has the advantage that they are particularly well protected against wear and falsification.

From the prior art, it is also known to introduce colorful individualizations in card body. From DE 100 53 264 A1, for example, a method for writing data, in particular personalization data, on and / or in a data carrier by means of electromagnetic radiation is known, wherein in the method any data carrier is provided on and / or in which at least one colorant is provided at least locally, and this colorant is irradiated by means of the electromagnetic radiation of at least one wavelength range, so that there is a change in the color of the colorant by bleaching in the field of Bestrahiung, said color is determined by machine and / or by a human eye.

DE 199 55 383 A1 describes a method for applying colored information to an object, wherein the article has at least two different coloring particles at least in a near-surface layer, which change the color of this layer under the influence of laser radiation, the laser radiation having At least two different wavelengths is used to change the color of this layer, and the irradiation of the article with laser radiation in vector and / or raster method via a two-coordinate beam deflector and a focusing device for focusing the laser radiation is applied to the layer of the object. In this method, absorbing color pigments are bleached by the different wavelengths in different wavelength ranges in order to change a color impression.

From DE 103 16 034 A1 a method for generating information in a carrier body is known, in which a simple long-term stable information against light and moisture is to be generated in the carrier body by simple means. These are for a number of in the carrier body Stored starting materials in a localized portion of the support body by laser irradiation set those reaction conditions that cause these starting materials to a synthesis reaction. Here, complex reaction processes are selected, which can only be specifically triggered by laser irradiation and not by sunlight to synthesize colored substances. A colored substance here is a substance that is colored regardless of its size and shape. In this way, different colored substances can be synthesized. However, the problematic is the targeted controllability of the individual colors. Another problem is to perform the color-forming reactions spatially resolved and without quenching to achieve a clear color.

The invention is therefore based on the technical problem of providing a method and an apparatus as well as a document body of a security document and a method for its production, with which it is possible to carry out a colored individualization, preferably after a production of the document body itself, in a simple manner ,

The problem is solved according to the invention by a method having the features of patent claim 1, a security document having the features of patent claim 11 and a device having the features of patent claim 22. Advantageous embodiments of the invention will become apparent from the dependent claims.

For this purpose, it is intended to use nanoparticles whose interaction with electromagnetic radiation, ie also with light in the visible wavelength range, depends on quantum mechanical effects which are influenced by their shape and / or a local concentration of the nanoparticles. For this purpose, a method for colored individualization of security documents comprising a document body are held in the starting materials, which are locally stimulated by a localized targeted energy input to create or change nanoparticles that produce a color impression, wherein a shape and / or a concentration of the nanoparticles locally in the document body is dependent on the energy input and wherein the color impression the nanoparticles is dependent on their shape and / or local concentration, proposed in which locally targeted energy is introduced at a point at which a colored color impression is to be brought about in the document body in order to store an individualizing information about the color impression caused. It is thus a security document, which includes a personalized color document body, created in the interior of the document body starting materials are provided, which are targeted by means of a localized energy input targeted for the formation of nanoparticles of different shapes and / or different concentration, the shape and / or concentration is dependent on the energy input and wherein a color impression of the nanoparticles is dependent on their shape and / or their concentration. A device for individualizing a said security document with a security document body comprises a document body receptacle for receiving the document body, a Energiequeiie for iokaiisierten introduction of energy input into the document body to change the color impression targeted so that an individualizing information is stored in the document body by the color effect effected , A security document with a document body that can be personalized in color is created by incorporating the starting materials into the document body during production.

In the case of a document body produced from several layers by means of lamination, the starting materials, for example by printing, can be introduced between two layers before lamination.

The shape of the nanoparticles, on the one hand, is understood to be their size and, on the other hand, their geometric shape. Nanoparticles made of semiconductor materials which have a band gap of preferably less than 2 electron volts in the solid state material (BuIk) often exhibit a so-called size quantization effect when a particle size is varied to smaller and smaller nanoparticles in the range of a few nanometers or below. The smaller the nanoparticle of this semiconductor becomes, the larger the bandgap becomes. Thus, the band gap energy is dependent on the size, ie the shape, of the nanoparticles. With the bandgap energy, in turn, the absorption behavior is electromagnetic Radiation linked. Thus, changing the bandgap energy also changes a color of the nanosheet, ie the color impression obtained when viewing the nanotech. In certain types of nanoparticles, the color impression, ie their absorption behavior, is influenced mainly by their surface shape. In the particles so-called surface plasmons are excited. These are critically dependent on a form of nanoparticles. Without a change in the volume, solely by a change in the shape of the nanoparticle, for example an aspect ratio in the case of a rod-shaped nanoparticle, formed from longitudinal expansion to transverse expansion, its absorption behavior can be changed as a function of wavelength. By color impression is thus meant primarily an absorption behavior of the nanoparticle. In addition, it will be apparent to those skilled in the art that the color impression also depends, of course, on the number of nanotubes present in a volume or area, since the number of particles affects the total absorption in the volume or area. However, this does not change the course of the absorption spectrum, but only the absorption efficiency. When talking about a change in the color impression in the context of the invention, such is not meant to be due to an increased / decreased absolute absorption.

This is to be distinguished from a change in the color impression of the nanoparticles due to their local concentration. In the case of nanoparticles, where the absorption behavior in the visible spectral range is determined mainly by an excitation of surface plasmons, a further concentration-dependent effect is added, which changes a wavelength dependence of the absorption and thus a color of the nanoparticles. Quantum-mechanical effects, which are based on the fact that the nanoparticles influence each other and, without forming a chemical bond, change the quantum-mechanical state functions of the electronic system of the individual nanoparticles in such a way that their absorption spectra and hereby their color is changed. For these nanoparticles, the concentration does not lead to a more intense color impression, but to a different color shifted color impression. This effect is referred to herein as the nonotope concentration-quantizing effect. Over a targeted local energy input into the Dokurnentenkörper can thus be a formation of nanoparticles, ie a creation or change of nanoparticles targeted effect and set targeted about almost any color of the optical spectral range localized. This makes possible a simple, colored individualization of security documents.

Importantly, most proposed systems do not require the introduced energy, usually also not as activation energy, to begin or execute nanoparticle formation that causes a change in color impression. Rather, the starting materials are introduced into the document body so that it prevents the systems at normal ambient temperatures, to form such a color impression producing nanotechnology. For example, tiny nanotechts that are not stabilized by embedding in a matrix, chemical solution, or the like, tend to grow together into larger nanoparticles. As a result, a total surface energy of the nanoparticles involved is reduced. Such a process is prevented by the embedding in the document body at ambient temperature and runs only where the document body is locally heated by the energy input.

In a preferred embodiment, the energy is introduced by means of one or more lasers. Lasers offer the advantage that their light can be focused well, so that energy can be supplied to the focus in a targeted manner. With a suitable choice of the laser wavelength, it is possible, depending on the material from which the document body is made, to make a colored individualization inside the document body and not only on a surface. Furthermore, the energy input by means of one or more lasers offers the advantage that the laser intensity and / or the laser frequency can be modulated in order to control the energy input and, via this, the formation process of the nanoparticles producing a desired color impression.

In a preferred embodiment, the starting materials comprise nanoparticles whose bank-gap energy is greater than that due to the size-quantization effect Photon energy of visible light is. These nanoparticles of the starting materials can be caused by a targeted introduction of energy into the document body to grow together to form larger nanoparticles and thus change their absorption spectrum and thus their color and the color impression due to the size quantization effect.

Thus, in one embodiment, the starting materials are preferably incorporated into a matrix. This is preferably designed so that the constituents of the starting materials can only move in the matrix when energy is introduced into the matrix and this is heated thereby.

In a particularly preferred embodiment, it is provided that the matrix consists of a polycarbonate, in particular bisphenol A polycarbonate. Polycarbonates are particularly suitable because they are transparent in the visible wavelength range for electromagnetic radiation. Nevertheless, by means of a laser so high radiation energy densities can be generated that the polycarbonate material can be heated locally targeted.

However, in order to improve an absorption of the laser light, it is provided in one embodiment of the invention that the starting materials contain activator material which has a good laser absorption. The activator material can be introduced in concentrations that do not adversely affect a transparency impression of the document body and yet significantly increase a locally targeted absorption of laser light. A laser wavelength can be adjusted to achieve good absorption in an activator material.

In a preferred development of the invention, it is provided that the activator material comprises zinc oxide ZnO. However, it can be used as activator, other substances, such as carbon black or Iriodin ^®.

In another embodiment of the invention it is provided that the starting materials additionally or alternatively precursor for the formation of nanoparticles whose absorption behavior of their shape and / or their local concentration depends. This means that their color impression depends on their shape and / or their local concentration. As precursors, therefore, such substances are present in the starting materials which form nanoparticles by a chemical reaction when energy is introduced into the document body and / or cause growth of already present smallest nanoparticles. By means of a targeted control of the energy supplied, in such an embodiment both a number of the nanoparticles created and their size can be specifically influenced. If a high energy input in a short time, so that a heating to a high temperature, for example 180 ⁰ C, is effected locally in the material, so a formation of a large number of nuclei is excited. If, on the other hand, an energy supply is selected such that locally a lower temperature, for example of 120 ^° C., results, then only a small formation of new crystallization nuclei takes place, but a size growth of the already existing nanoparticles proceeds at this low temperature.

The local temperature can thus be varied over time by means of a targeted energy supply and a process control can be achieved by way of this, so that an optimum desired color impression, ie a desired color, can be set. As a particularly suitable substance have Il-Vl Halbleitemanoteilchen turned out. However, other suitable systems or substances, for example cadmium phosphide Cd ₃ P ₂ , etc. are also known. In principle, it is possible to use all substances which exhibit a shape-dependent absorption behavior in the visible wavelength range, in particular a large-, shape- and / or concentration-dependent absorption behavior (again meaning a change in the absorption spectrum (whose wavelength-dependent profile) as a function of the concentration). ,

The IL-VI semiconductor nanoparticles found to be particularly suitable generally have a large size quantization effect. The preferred materials include, for example, cadmium or mercury sulfide, cadmium or mercury selenide, cadmium or mercury telluride and ternary or quaternary compounds of the aforementioned elements. To effect formation of these nanoparticles or size growth already existing To support or excite nanoparticles, the starting materials may comprise, for example, cadmium acetate and / or mercuric acetate and thioacetamide, from which cadmium sulfide or mercury sulfide forms upon energy input.

In a further embodiment, the starting materials comprise form-quantisable nanoparticles which change their shape as a function of the energy input, the color impression of which depends on the mold. Form-quantisable nanoparticles may, for example, consist of gold and / or silver and / or alloys thereof. The starting materials may comprise, for example, gold rod-shaped nanoparticles. By introducing energy, these nanoparticles can be excited to transform toward a spherical shape. Here, the absorption spectrum changes, which is mainly dominated by surface plasmon excitations.

In particular, nanoparticles of gold and silver alloys have a concentration-dependent color impression. Their absorption behavior is dependent on an average distance to an adjacent nanoparticle. In a preferred embodiment of the invention, starting materials comprise precursors of substances which form colloidal nanoparticles whose color impression depends on a local concentration of the colloidal nanoparticles. For example, the starting materials may contain zinc oxide (ZnO) and gold or silver salts. In laser irradiation, the ZnO acts as an electron supplier to reduce gold or silver. This can be a growth of nano-colloids of gold and / or silver are excited.

The introduction of the energy is carried out so that a chemical degeneration, in particular a depolymerization, pyrolysis or carbonization, of the material of the document body is omitted.

In a preferred embodiment, there are optical sensors which monitor a color impression. The energy supply is then controlled as a function of the monitored color impression. Particularly preferably, the energy is localized at several points in a targeted manner introduced into the document body to bring about a color impression at the plurality of locations due to the shape and / or concentration of the nanoparticles, wherein the plurality of locations provide a pattern containing the individualizing information. Preferably, different color impressions are caused by the energy input at the different points. This means that the energy input takes place differently at the different locations.

The invention will be explained in more detail with reference to a preferred embodiment. Hereby show:

Fig. 1 shows schematically potentials for different sized particles, each for

Valence and conduction band;

Fig. 2 absorption curves for different sized particles;

3 shows a course of the band gap as a function of the particle size for size-quantisable particles;

Fig. 4 nanoparticles of different shape; and

5 shows a device for individualizing a security document with a document body that can be personalized in color.

FIG. 1 shows box potentials for the conduction band 1a, 1b, 1c and corresponding box potentials for the valence band 2a, 2b, 2c for three different particle sizes a, b, c. A width 3a, 3b, 3c of the individual box potentials 1a, 2a, 1b, 2b, 1c, 2c is dependent on a particle size in the box model in each case. The larger the particle, the wider the corresponding box potentials. Here the particle a is the smallest particle and c the largest particle.

If one determines in these box potentials 1a-1c, 2a-2c, respectively, the energetically lowest results taking into account quantum mechanics Energy levels 4a-4c of the conduction band and the highest energy states 5a-5c of the valence band, resulting for the different large particles ac different energy difference 6a-6c, each of which can be associated with a band gap energy. The energy difference 6a-6c decreases with increasing particle size. The larger the bandgap of a particle, the higher the energy must be the radiation that is absorbed by this particle.

By contrast, photons whose energy is less than the bandgap energy are not absorbed. This means that as the particle size increases, there is a red shift in the absorption edge. This is shown schematically in Fig. 2. There, the absorption for differently sized particles is plotted against the wavelength. Absorption edges 11a-11c of the absorption curves 12a-12c show a shift to longer wavelengths, i. a redshift with increasing particle size, whose increase is indicated by an arrow 13. When changing the particle size, a corresponding behavior is shown.

For cadmium phosphide Cd ₃ P ₂ the band gap in the solid is 0.55 eV. At a mean particle diameter of 3 nm, the material no longer appears black, but brown. As the diameter decreases further, the color changes to red, orange and yellow until the material appears white at about 1.5 nm and has a bandgap of about 4 eV.

In Fig. 3, the energetic course of the conduction band 15 and the valence band 16 is in each case schematically plotted against the particle size. With small particle size, the bandgap energy 17 is large, for example in the region of 4 eV. Particles of this size appear white. With increasing particle size, the bandgap energy 17 decreases and the color changes from yellow to orange, red to brown and finally black.

A similar energetic effect occurs, for example, with rod-shaped gold particles. FIG. 4 schematically shows a nanoparticle 21 whose aspect ratio, a ratio of a length 22 to a width 23, decreases. Such a rod-shaped nanoparticle, a nanoparticle with a high aspect ratio, is used as a starting material, for example, in one of polycarbonate embedded matrix embedded. When this matrix is heated, the nanotechings are given the opportunity to change their shape. A reduction of the aspect ratio leads to a reduction of the surface and thus a surface energy, so that this conversion of the originally rod-shaped nanoparticle 21 is prevented only by the matrix. Only when the matrix and the nanotechts warm up is the nanotech cake given the opportunity to change its shape to a spherical shape. Here, the volume of the nanoparticle remains unchanged. As the aspect ratio changes, its absorption behavior also changes from the infrared to the visible.

FIG. 5 schematically shows a device 41 for laser personalization of a security document 42, which comprises a document body 43 that can be individually colorized. The document body 43 is preferably a composite body made of several layers 44 by lamination. These layers 44 are preferably formed from one or more thermoplastic materials. Single layers or all layers may be printed before laminating. Furthermore, microchips or other security elements may be incorporated in single or multiple layers. At least one layer, preferably a plurality of layers, are formed in such a way that starting materials for forming size-scalable nanotechings are incorporated in them. The nanotech can also be introduced between two layers, for example by printing technology. A layer is for example made of bisphenol A polycarbonate. This material provides a matrix for the starting materials. In this matrix, for example, smallest nanotechnology of substances are embedded whose bandgap energy is above the energy of photons of visible light. Additionally or alternatively, precursors, for example cadmium acetate and thioacetamide, may be embedded in the matrix. For example, zinc oxide ZnO is incorporated into the matrix as activator material.

The document body is held in a document body receptacle 55.

The device 41 includes a laser 45 as an energy source. This laser 45 generates electromagnetic radiation in the infrared, visible and / or ultraviolet spectral range. For example, the laser 45 may be selected from the list "YAG: Nd (fundamental or frequency multiplied: 1064 nm, 532 nm, 355 nm, 266 nm), excimer laser (F ₂ 157 nm, Xe 172 nm), exciplex laser (ArF 193 nm, KrF 248 nm, XeBr 282 nm, XeCl 308 nm, XeF 351 nm), titanium sapphire laser, CO ₂ laser (10.6 μm) or diode laser. "This laser radiation 46 is focused with imaging optics 47 localized in a region of the layers 44, In a focus 48, the laser radiation 46 is preferably absorbed by an activator material, for example, zinc oxide (ZnO), which results in a hot spot, which stimulates formation of cadmium sulfide Depending on the laser intensity, different numbers of nanoparticles form, the higher the laser intensity, ie, the higher the temperature of the matrix rises locally, the more nanoparticles are created chooses, fewer or no nanoparticles are created. However, growth of existing nanoparticles continues. In this case, the size of the nanoparticles 49 changes. Depending on the size, a color impression changes.

In another embodiment, irradiation of the activator material, for example, zinc oxide (ZnO), results in the formation of electron-hole pairs, thereby reducing, for example, metal salt ions, particularly silver (Ag ⁺ ) and gold (Au ³⁺ ), to the corresponding metals and form nanoparticles.

By means of an optical sensor 50, which is formed for example as a color CCD camera, the optical impression is monitored. For this purpose, it may be necessary for the document body 43 to be illuminated with a light source 51. The signals detected by means of the optical sensor 50 are evaluated by a control device 52 which controls an energy input via the energy source 41 designed as a laser 45. The energy source 41 may further include a modulator 54 through which the frequency and / or amplitude of the laser is modulated to control the energy input into the document body 43. The modulator may be integrated into the laser 45 in other embodiments. It will be apparent to those skilled in the art that the energy source may also include multiple lasers that emit light of different wavelengths. This makes it possible to optimally excite different activator materials.

In other embodiments, provision can be made for nanoparticles to be created to change the color impression in a plurality of different layers of the document body. If the laser radiation is focused simultaneously or with a time delay at different locations in the document body in order to selectively introduce locally targeted energy and to create nanoparticles that produce an optical color impression in the visible spectral range, a colored pattern can be generated in the document body, which is an individualizing information, for example a name, a passport photo, etc. represents.

In some embodiments, the document body itself is a voiiständiges security document or document of value. In other embodiments, the document body is incorporated, for example, in a passport book.

In some embodiments, the document body is a multi-layer laminated composite in which different layers include different starting materials and / or concentrations thereof. This can be caused in a simple manner in the different layers different color impressions by localized energy input. These can together result in a color pattern. Likewise, however, the layers may also comprise the same starting materials and / or concentrations thereof.

It will be apparent to those skilled in the art that the invention will find application primarily in the visible spectral range. However, embodiments are also conceivable which produce a color impression which is provided only for a machine test. On the one hand because the color impression caused is in the UV or IR spectral range or because a nanoparticle concentration is produced whose absorption intensity is not sufficiently high for a human test. Here is meant the intensity ratio of the absorption and not its wavelength-dependent course. Again, the information by changing a stored wavelength-dependent changed color impression. Only a number of the color-changed nanoparticles produced is deliberately kept low.

The described embodiments are merely exemplary embodiments. It will be apparent to those skilled in the art that there are a variety of modification possibilities.

LIST OF REFERENCE NUMBERS

1a-1c box potential of the conduction band

2a-2c box potential of the valence band

3a-3c width of the box potential

4a-4c energy level of the conduction band

5a-5c energy level of the valence band

6a-6c energy difference

11 a-11 c absorption edge

12a-12c absorption spectra

13 arrow (in the direction of increasing particle size)

15 conduction band

16 valence band

17 Biπduπgsenergiθ

21 nanoparticles

22 Length 3 Width 1 Device for colored individualization of security documents 2 Security document 3 Document body 4 Layers 5 Laser 6 Laser radiation 7 Imaging optics 8 Focus 9 Nanoparticles 0 Optical sensor 1 Light source 2 Control 4 Modulator 5 Document body holder

Claims

claims

A method for colored individualization of security documents (42), which comprise a document body (43) in which starting materials are excited, which are locally stimulated by a localized targeted energy input to create or change nanoparticles (21; Shape and / or a concentration of the nanoparticles (21; 49) locally in the document body (43) is dependent on the energy input and wherein a color impression of the nanoparticles (21; 49) depends on their shape and / or local concentration in which locally targeted energy is introduced at a point at which a colored color impression in the document body (43) is to be brought about to store an individualizing information about the color impression caused.

2. The method according to claim 1, characterized in that the energy by means of a laser (45) is introduced.

3. The method according to claim 1 or 2, characterized in that the energy is introduced in time varies.

4. The method according to any one of claims 1 to 3, characterized in that the laser intensity and or laser frequency is modulated to control the energy input in time.

5. The method according to any one of claims 1 to 4, characterized in that the laser wavelength is adjusted to achieve a good absorption in an activator material comprising the starting materials.

6. The method according to any one of claims 1 to 5, characterized in that the introduction of the energy is carried out so that a chemical degeneration, in particular a depolymerization, pyrolysis or carbonization, of the material of the document body (43) is omitted.

7. The method according to any one of claims 1 to 6, characterized in that a color impression is monitored and the energy supply is controlled in dependence of the monitored color impression.

8. The method according to any one of claims 1 to 7, characterized in that the energy is localized selectively introduced into several areas in the document body to bring about a color impression due to the nanoparticles at the plurality of locations, wherein the plurality of points yield a pattern that the contains individualizing information.

9. The method according to any one of claims 1 to 8, characterized in that at the different points by the energy input different color impressions are caused.

10. The method according to any one of claims 1 to 9, characterized in that different nanoparticles are generated selectively by varying the energy input.

11. Security document (42) which comprises a color-customizable document body (43) in which inside the document body (43) starting materials are provided, which by means of a localized energy input targeted for the formation of nanoparticles (21; 49) of different shape and / or different concentration can be excited, wherein the shape and / or concentration is dependent on the energy input and wherein a color impression of the nanoparticles (21; 49) depends on their shape and / or their concentration.

12. Security document (42) according to claim 11, characterized in that the starting materials comprise nanoparticles whose band gap energy is greater than the photon energy of visible light due to a size quantization effect.

13. Security document (42) according to claim 11 or 12, characterized in that the nanoparticles present in the starting materials tend to have a particle size growth effecting a size quantization effect.

14. Security document (42) according to claim 11, characterized in that the starting materials comprise precursors for forming nanoparticles (21, 49) which have a size quantization effect or form quantization effect or nanoparticle concentration quantization effect.

15. Security document (42) according to any one of claims 11 to 14, characterized in that the starting materials are incorporated in a matrix.

16. Security document (42) according to any one of claims 11 to 15, characterized in that the matrix consists of one or more polycarboxylate, in particular a bisphenol A polycarbonate.

17. Security document (42) according to any one of claims 11 to 16, characterized in that the starting materials contain activator material having a good laser absorption.

18. Security document (42) according to any one of claims 11 to 17, characterized in that the activator material comprises zinc oxide (ZnO).

19. The security document (42) according to claim 11, characterized in that the starting materials contain form-quantisable nanoparticles (21, 49) which change their shape as a function of the energy input into the document body (43), the color impression of which being of the shape is dependent.

20. Security document (42) according to any one of claims 11 to 19, characterized in that the starting materials contain precursors of substances which form nano-colloids whose color impression is dependent on a local concentration of nano-colloids.

The security document (42) according to any one of claims 11 to 20, characterized in that the document body (43) is a composite body laminated from multiple layers (44) and different ones of the plurality of layers (44) of the document body (43) comprise different source materials.

22. Device (41) for individualizing a security document (42), which comprises a colored by means of an energy input document body (43), in which inside the document body (43) starting materials are kept, the targeted by means of a localized energy input depending on the energy input to Formation of nanoparticles (21; 49) of different shape and / or number are excitable, wherein a color impression of the nanoparticles (21; 49) is dependent on their shape and / or concentration, comprising a document holder body (55) for receiving the document body (43), an energy source for localized introduction of the energy input in the document body (43) to change the color impression so that an individualizing information in the document body (43) is stored by the effected color impression.

23. Device (41) according to claim 22, characterized in that the energy source comprises a laser (45).

24. Device (41) according to claim 22 or 23, characterized in that a controller (52) for timing the energy input is coupled to the energy source.

25. Device (41) according to any one of claims 22 to 24, characterized in that an optical sensor (50) is coupled to the controller (52) to control the energy input depending on the detected color impression.