DE102014207318B4 - Identification feature with several identification elements arranged in a defined, limited area for identifying an object - Google Patents

Abstract

Identification feature (01) with a plurality of identification elements arranged in a defined, limited area for identifying an object, wherein in a first operating state of the identification feature (01) by irradiating the area containing the identification elements with visible light, a first identification element is visually recognizable and a second identification element is visually recognizable is not recognizable, wherein the second identification element is designed as a random structure formed from pigments (03), wherein in a second operating state of the identification feature (01) by irradiating the surface containing the identification elements with electromagnetic radiation that differs from the first operating state, at least the random structure of the second identification element is visually recognizable, the first identification element being an arrangement of characters and/or carriers of meaning that belong to a code is formed, the pigments (03) of the second identification element being contained in a printing ink or in an ink, the random structure of the second identification element being a representation of second machine-readable information, characterized in that each of the characters or carriers of meaning of the arrangement of the first identification element is formed as a raster graphic consisting of pixels (02), the pixels (02) of the first identification element being formed from the printing ink or ink contained in the pigments (03) of the second identification element, the pigments (03) of the second identification element forming a core with a carrier substance and with either a fluorescent material or a phosphorescent material, there being provided a shell surrounding the core, the shell containing photochromic material with which one of the fluorescent material or the phosphorescent mate rial emitted radiation can be attenuated, the pixels (02) containing the pigments (03) of the second identification element being arranged in an offset printing process or in an inkjet printing process on or on the object.

Description

The invention relates to an identification feature with a plurality of identification elements arranged in a defined, limited area for identifying an object according to claim 1.

Electromagnetic radiation in a wavelength range from about 380 nm to 780 nm or 790 nm is generally referred to as the light spectrum and can be perceived by humans as light with their eyes. Since the sensitivity of the human eye does not abruptly but gradually decreases at the limits of perception, it makes little sense to delimit the light spectrum too precisely. In addition, the perception of color for individual wavelengths differs slightly between people. Therefore, the Commission Internationale de l'Eclairage (CIE) empirically determined spectral sensitivities for wavelengths and defined a standard valence system in order to establish a relationship between human color perception (color) and the physical causes of a color stimulus (color valence). The CIE standard valence system captures all of the colors that humans can perceive. The wavelength ranges adjacent to the light spectrum are ultraviolet radiation in the short-wave range and infrared radiation in the long-wave range.

In classical electrodynamics, light is understood as a high-frequency electromagnetic wave. Ray optics, also known as geometric optics, uses the approximation that the propagation of light can be illustrated by straight rays. This approximation is justified above all when the dimensions of the object or structure to be examined are large compared to the wavelength of the light. Then all diffraction phenomena can be neglected. Diffraction is the deflection of waves at an obstacle. Through diffraction, a wave can propagate into areas of space that would be blocked by the obstacle on a purely straight path. However, diffraction is no longer negligible when geometric structures play a role whose size is comparable to the wavelength of the waves used. In quantum physics, light is no longer understood as a classical wave, but as a quantum object. Accordingly, the light is made up of individual discrete energy quanta, the so-called photons. A photon is an elementary particle that always moves at the speed of light.

Absorption:

Die Energie des einfallenden Lichts wird von der Materie eines Körpers aufgenommen. Dies kann dazu führen, dass ein in der Materie vorhandenes Elektron auf ein höheres Energieniveau gehoben wird und sich der Körper erwärmt. Wenn die Strahlung unabhängig von ihrer Wellenlänge von der Materie absorbiert wird, erscheint der Körper schwarz. Wird nur ein Teil des Lichtspektrums absorbiert, so bestimmen die übrig gebliebenen Teile des Lichtspektrums durch eine subtraktive Farbmischung die Farbe des Körpers. Trifft weißes Licht auf einen Körper, wird das einfallende Licht teilweise reflektiert und teilweise absorbiert. Wenn kurzwellige Anteile des Lichtspektrums ab 380 nm vom Körper absorbiert werden, so enthält die remittierte Strahlung vorwiegend langwellige Anteile bis 790 nm und die remittierte Strahlung wird mit dem Farbeindruck Rot wahrgenommen. Bei vorwiegend langwelliger Absorption bis 790 nm ist die Farbwahrnehmung aus dem reflektierten Licht Violett. Im Falle einer elektronischen Anregung der Materie kann Energie auch wieder in Form von Strahlung abgegeben werden. Man spricht von spontaner Emission, von Fluoreszenz oder - wenn der Vorgang zeitlich verzögert erfolgt und/oder deutlich länger anhält - von Phosphoreszenz.

Reflexion:

An spiegelnden Flächen, z. B. an einer blanken Oberfläche eines Metalls, wird Licht nach dem Reflexionsgesetz reflektiert. Dabei liegen der einfallende Lichtstrahl und der ausfallende Lichtstrahl sowie das Lot auf der reflektierenden Fläche in einer Ebene. Einfallswinkel und Ausfallswinkel sind einander gleich. Das Verhältnis der reflektierten Lichtintensität zur einfallenden Lichtintensität wird als Reflexionsgrad bezeichnet und ist material- und wellenlängenabhängig.

Streuung:

Das Licht ändert seine Ausbreitung, jedoch nicht wie bei der Reflexion in eine definierte Richtung, sondern diffus in alle möglichen Raumrichtungen. Je nach dem streuenden Körper unterscheidet man zwischen Compton-Streuung (an freien Elektronen), Rayleigh-Streuung (an gebundenen Elektronen ohne Energieübertrag), Raman-Streuung (an gebundenen Elektronen mit Energieübertrag) und Mie-Streuung (an Teilchen, deren Ausdehnung in der Größenordnung der Wellenlänge liegt).

Brechung:

Licht wird an einer Grenzfläche zwischen zwei Medien unterschiedlicher optischer Dichte gebrochen, d. h. ein Lichtstrahl ändert an dieser Grenzfläche seine Richtung. Manche Materialien spalten einen Lichtstrahl in zwei Strahlen unterschiedlicher Polarisation auf. In diesem Fall spricht man von einer Doppelbrechung.

Optische Aktivität:

Bestimmte Medien drehen die Polarisationsebene von polarisiertem Licht.

Photoeffekt:

Die Photonen der einfallenden Strahlung lösen Elektronen aus dem bestrahlten Körper.

When light meets matter, there are interactions with the matter that manifest themselves in one or more of the following phenomena:

Absorption:

The energy of the incident light is absorbed by the matter of a body. This can result in an electron present in matter being raised to a higher energy level and the body heating up. When the radiation is absorbed by matter, regardless of its wavelength, the body appears black. If only part of the light spectrum is absorbed, the remaining parts of the light spectrum determine the color of the body through subtractive color mixing. When white light hits a body, some of the incident light is reflected and some is absorbed. If short-wave parts of the light spectrum from 380 nm are absorbed by the body, the remitted radiation mainly contains long-wave parts up to 790 nm and the remitted radiation is perceived with the color impression red. With predominantly long-wave absorption up to 790 nm, the color perception from the reflected light is violet. In the case of an electronic excitation of matter, energy can also be released again in the form of radiation. One speaks of spontaneous emission, of fluorescence or - if the process takes place with a time delay and/or lasts significantly longer - of phosphorescence.

Reflection:

On reflective surfaces, e.g. B. on a bare surface of a metal, light is reflected according to the law of reflection. The incident light beam and the emerging light beam as well as the perpendicular lie in one plane on the reflecting surface. Angle of incidence and angle of reflection are equal to each other. The ratio of the reflected light intensity to the incident light intensity is referred to as the degree of reflection and depends on the material and wavelength.

Scattering:

The light changes its propagation, but not in a defined direction as in the case of reflection, but diffusely in all possible spatial directions. Depending on the scattering body, a distinction is made between Compton scattering (on free electrons), Rayleigh scattering (on bound electrons without energy transfer), Raman scattering (on bound electrons with energy transfer) and Mie scattering (on particles whose expansion is in the order of magnitude of the wavelength).

Refraction:

Light is refracted at an interface between two media of different optical density, ie a ray of light changes its direction at this interface. Some materials split a light beam into two beams of different polarization. In this case one speaks of a double refraction.

Optical activity:

Certain media rotate the plane of polarization of polarized light.

photo effect:

The photons of the incident radiation release electrons from the irradiated body.

A color stimulus is created by absorption and remission (i.e. scattering or reflection) of certain frequency components of visible light. Color stimulus is the physical characterization of the radiation of visible light which, by directly stimulating the retina of the eye, evokes a perception, which perception can be perceived as color. The color stimulus can come from a primary light source, i. H. from a self-radiator, i. H. from a self-luminous source, as well as from a secondary light source, i. H. emanate from an illuminated body. A color stimulus caused by a primary light source is referred to as a light color, whereas a color stimulus caused by a secondary light source is referred to as body color. Body colors change the spectral composition of the incident light according to a transmission and remission behavior of the material of the body in question.

A relative spectral radiation distribution S _{λ is} decisive for the color stimulus, ie the "stimulating" radiation in its dependence on the wavelength and not in its absolute size or intensity. The spectral distribution that determines the color perception is called the color stimulus function φ(λ). In the case of a self-radiator, this function is equal to its spectral distribution S(λ). In the case of a secondary light source, i.e. a body colour, the color stimulus is determined by the product of the radiance factor β(λ) and the spectral distribution of the light source.

• Der Lichtstrom, gemessen in der SI-Einheit Lumen (Im), ist die Strahlungsleistung einer Lichtquelle, gewichtet mit der Hellempfindlichkeitskurve, und entspricht der radiometrischen Größe Strahlungsleistung, d. h. dem Strahlungsfluss oder der Strahlungsenergie pro Zeit, gemessen in der SI-Einheit Watt (W).

Radiometry is the science of measuring and applying electromagnetic radiation. The quantitative measurement of radiation intensities is carried out with different types of detectors. The detectors for the physical measurement of radiation quantities are called radiometers. These detectors convert part of the radiation into heat or into an electrical signal, from which conclusions can be drawn about the type of radiating surface and its temperature, among other things. Photometry or photometry refers to measurement methods in the wavelength range of visible light and the ultraviolet spectral range using a photometer, with a photometer or photometer being an instrument for measuring at least one photometric variable. Photometric quantities are derived from the associated radiometric quantities. The difference between a photometric quantity and a corresponding radiometric quantity is that in photometry the sensitivity of the observer is taken into account by multiplying the radiometric quantity by a CIE standardized spectral luminous sensitivity curve, also known as the V-lambda curve will. An index v (in non-italics) for "visual" appended to the quantities, as is conventional, stands for the reference to visible light, i.e. typically the spectral range from 380 nm to 780 nm. The following photometric quantities exist:

• Luminous flux, measured in the SI unit lumen (Im), is the radiant power of a light source, weighted with the light sensitivity curve, and corresponds to the radiometric quantity radiant power, i.e. the radiant flux or radiant energy per time, measured in the SI unit watt (W ).

The amount of light, measured in the SI unit lumen second (Ims), is the radiant energy of a light source weighted by the sensitivity curve and corresponds to the radiometric quantity radiant energy, i.e. the amount of radiation or the energy of a number of photons emitted as a stream of Electromagnetic radiation assumed to be photons is transported, measured in the SI unit Joule (J).

Luminous intensity, measured in the SI unit candela (cd), is the luminous flux per solid angle measured at a great distance from the light source and corresponds to the radiometric quantity of radiant intensity, i.e. H. the radiant intensity, radiant intensity or radiant flux per solid angle, measured in the SI unit watts per steradian (W/sr). Luminous intensity indicates how intensively a light source shines in a certain direction. For a spatially isotropic light source, the luminous flux is equal to the luminous intensity multiplied by 4π, the full solid angle.

Illuminance, measured in the SI unit Lux (Ix), is the luminous flux per illuminated area and corresponds to the radiometric variable irradiance, i.e. the radiant flux density or the radiant flux per effective receiver area, measured in the SI unit Watt per square meter (W / ^m2 ). The illuminance indicates how intensively the surface is illuminated.

The radiant emittance, measured in the SI unit Lux (Ix), is the luminous flux emitted, related to the size of the light-emitting area, and corresponds to the radiometric quantity emittance or radiant flux density, i.e. the radiant flux per effective emitter area, measured in the SI -Unit watts per square meter (W/m ² ).

Luminance, measured in the SI unit candela per square meter (cd/m ² ), is the luminous intensity of a light source in relation to its projected area (perpendicular to the viewing direction) and corresponds to the radiometric quantity radiance, ie the radiant flux per solid angle per effective Emitter area, measured in SI units of watts per square meter and steradian (W/(m ² sr)). The luminance is recorded by an image-capturing optical system, e.g. B. man or a camera, as the brightness of a light-emitting surface true.

The properties of a radiation source, a receiver and the irradiated material can be described with the photometric quantities or the corresponding radiometric quantities.

An emission spectrum is the electromagnetic spectrum emitted by atoms, molecules, or materials with no incident electromagnetic radiation of the same frequency. The counterpart of an emission spectrum is the absorption spectrum. While discrete energy levels give rise to a line spectrum, energy bands give rise to a continuous spectrum. An atomic spectrum is the emission spectrum of a single isolated atom, that is, the intensity of the light it emits as a function of wavelength or frequency. The spectral lines each correspond to the energy difference between two different states of the atom. This energy difference is applied, for example, by an absorbed photon and then given off in the form of another photon with that energy, i.e. emitted. This energy (or the line in the spectrum) is discrete, so it cannot assume any values. This means that each atom - according to its electron configuration - can only emit particles of discrete wavelengths. The wavelengths of the emitted particles are therefore specific to a particular element. The fact that the “lines” in the spectrum ('peaks') are curves with a certain width is based on quantum effects. The spectral lines become broader with increasing gas pressure. At very high pressure, the line width can increase to such an extent that a continuum of light is observed, similar to that of a solid. The reason for this is the increasingly frequent mutual disturbance of the atoms when they collide. If an electron is completely detached from the atom by absorption of a photon, the atom is said to be ionized. Depending on the initial state of the electron, a certain minimum energy is required for this. Since ionization becomes possible for a continuous energy range above the minimum energy, a continuum is possible. The reverse process, i. H. the emission of a photon when capturing an electron is called recombination of the electron with the positive ion. This process produces continuous radiation, the boundary continuum. While the emission spectrum of diluted gases results in a line spectrum, hot solids and liquids emit a continuous spectrum because the individual atoms also interact with each other and the discrete quantum states thus merge into one another. Such a continuous spectrum can be calculated by multiplying the spectrum of a black body body (Planck's radiation law) at the same temperature by the absorption coefficient for electromagnetic radiation of the "object" at the respective wavelength.

Solids are matter in the solid state of aggregation, especially at a temperature of 20°C. In technical terms, solids have a certain minimum extent, which is not clearly defined. They are therefore macroscopic bodies - in contrast to microscopic ones bodies, such as B. Atoms and molecules. A distinction is made between amorphous, ie “amorphous” on the smallest scale, polycrystalline and crystalline solids. Polycrystalline solids consist of a collection of small single crystals that are built into a large whole in a disorderly manner.

An absorption or absorption line spectrum is an electromagnetic spectrum that arises when broadband, especially white light radiates through matter and light quanta, i. H. Photons of certain wavelengths or wavelength ranges are absorbed (resonance absorption). The absorbed photons are missing in the light passing through, which means that the so-called Fraunhofer lines are formed in the spectrum. Therefore, the spectrum at the relevant wavelengths is dark or, in extreme cases, black.

An absorption band is a wavelength interval in which the electromagnetic radiation, e.g. B. solar radiation, by chemical substances such. B. atmospheric gases such as carbon dioxide, carbon monoxide, ozone, methane and others. is selectively absorbed on the way to the recipient. The originally continuous spectrum of the radiation source only arrives at the receiver with dark gaps, these gaps forming the so-called absorption bands. Certain intervals of the entire wavelength range emitted by the radiation source are no longer available. An image of the spectrum obtained by selective absorption is called a band spectrum. An absorption band consists of a larger number of individual, i. H. singular, closely spaced absorption lines. The absorption bands arise as a result of the coupling of electrical vibrational and rotational excitation in molecules, so that no single energy difference is absorbed, but rather a whole spectrum of energy values, depending on the excitation of the molecules, i. H. the absorption spectrum. The different molecules each absorb only in a wavelength range that is specific to them. If the photons of the electromagnetic radiation emitted by a radiation source are absorbed by these photons exciting atoms, then these are sharply defined amounts of energy and therefore wavelengths, and the dark areas are correspondingly narrow lines. In molecules, on the other hand, many absorbable energy values are often close together and form broader dark areas in the spectrum, i. H. the absorption bands. In each case, the observed absorption spectrum is characteristic of the type of matter through which the radiation is traversing. For this reason, spectroscopy, usually carried out in different wavelength ranges, is an important method for analyzing substances. If free atoms, e.g. B. in a gas or vapor, the photons are re-emitted after absorption, uniformly in all spatial directions. If the light is only radiated in from one direction, the light that has passed through is found for the type of atom present, i.e. H. for the chemical element in question, typical absorption spectrum as a line spectrum. The light scattered in the other spatial directions shows the corresponding emission spectrum.

In the spectroscopy of solids, relaxation in the solid can occur between absorption and possible emission. A part of the energy of the photons z. B. converted into heat. In this case, the absorption and emission spectra are not complementary to one another, as is the case with the free atoms.

Luminescence is the optical radiation of a physical system that arises during the transition from an excited state to the ground state. Different types of luminescence are distinguished depending on the type of excitation. So e.g. B. electroluminescence excited by electric current, z. B. in light-emitting diodes (LED). Photoluminescence is excited by photons, with a distinction being made between phosphorescence and fluorescence depending on the time between excitation and emission of the light. Radioluminescence is excited by exposure to alpha or beta radiation, or by X-rays. Superluminescence arises from optical pumping, where spontaneously emitted light is amplified by stimulated emission in an optically active medium. Chemiluminescence is excited by a chemical reaction.

A light-emitting diode (LED) is a light-emitting semiconductor component whose electrical properties correspond to those of a pn semiconductor diode. When an electric current flows through the diode in its forward direction, a light-emitting diode emits electromagnetic radiation with a wavelength (λ) dependent on the semiconductor material and its doping, this radiation being either visible light or infrared radiation or ultraviolet radiation.

The ability of a solid to absorb light, as is the case for a semiconductor, is linked to the condition that it absorbs the photon energy by exciting electrons. Since electrons are in an energetic distance between a valence band and a conduction band of the solid, ie cannot be excited in its so-called band gap, the energy of a photon must exceed the energy of the band gap. Otherwise the photon cannot be absorbed. The energy of a photon is coupled to the frequency of the electromagnetic radiation via Planck's constant. If a solid has a band gap, then apart from special effects it is transparent to radiation below a certain frequency or above a certain wavelength (λ). The energy of a photon emitted by a solid is equal to the energy of the band gap, i.e. the energetic distance between the conduction and valence bands. The energy of the band gap first decreases quadratically, then more or less linearly, with increasing temperature due to thermal expansion of the lattice, starting from a maximum value at the temperature of zero Kelvin. The temperature dependence of the band gap depends on the material and can be calculated e.g. B. with the Varshni formula. The size of the band gap, ie the energy gap, determines the energy, ie the frequency, wavelength or color of the radiation or the emitted light. It can be controlled via the chemical composition of the semiconductor. The exchange of atoms in the crystal lattice changes the crystalline and/or molecular structure of the material, including its lattice parameters or even its lattice structure. The properties of the generated radiation can be varied by a targeted selection of the semiconductor materials and their doping. In this way, the spectral range and the efficiency in particular can be influenced. For example, light-emitting diodes made of the commonly used semiconductor material indium gallium nitride (InGaN) or gallium nitride (GaN) emit in the ultraviolet (230 nm < λ < 400 nm), violet (400 nm < λ < 450 nm), blue (450 nm < λ <) depending on the doping 500 nm) or green (500 nm < λ < 570 nm) spectral range. Light-emitting diodes emit in a limited spectral range Δλ z. B. of a maximum of Δλ ≈ 30 nm, so their radiation is almost monochromatic. With a light-emitting diode z. B. from the material indium gallium nitride (InGaN, In _x Ga _1-x N), which is a III-V semiconductor, which is formed from the two basic substances gallium nitride and indium nitride, results in a ratio of 2% indium nitride and 98% Gallium nitride a bandgap that provides near-ultraviolet emission. With 20% indium nitride and 80% gallium nitride, on the other hand, a blue-violet radiation with a wavelength of 420 nm is produced. A ratio of 30% / 70% results in radiation with 440 nm, which corresponds to a blue color. Other materials for light-emitting diodes form z. B. II-VI compounds or the chemical elements Si and Se.

1. a) Es können verschiedene Leuchtdioden z. B. in ein und demselben Bauteil verwendet werden. Blaue Leuchtdioden werden mit gelben oder mit roten und grünen so kombiniert, dass sich ihr Licht gut mischt und damit als weiß erscheint.
2. b) Es wird eine blau emittierende LED oder eine UV-LED mit einem Leuchtstoff z. B. in Form einer Lumineszenzschicht aus einem photolumineszierenden Material oder einem Lumineszenzfarbstoff kombiniert. So kann kurzwelliges, höherenergetisches Licht, insbesondere blaues Licht oder eine Ultraviolettstrahlung, in langwelligeres Licht umgewandelt werden. Beispielsweise wird eine blaue LED mit Cer-dotiertem Yttrium-Aluminium-Granat-Pulver kombiniert. Da blaue LEDs den höchsten Wirkungsgrad haben, UV-LEDs hingegen weniger als die Hälfte, ist das die wirtschaftlichste Methode, weißes Licht mittels LED zu erzeugen, aber mit dem Nachteil eines Blaustichs des weißen Lichts. Der Ultraviolett-Anteil, den blaue LEDs am kurzwelligen Ausläufer ihres Strahlungsspektrums aussenden, wird durch die Lumineszenzschicht ebenfalls weitgehend in gelbliches Licht umgewandelt. Bei einem Herstellungsverfahren für weiße LEDs wird z. B. Galliumnitrid epitaktisch auf einen Träger z. B. aus Saphir oder Silizium aufgebracht. So entsteht die erste Schicht des GaN-Halbleiterkristalls. Die lichtemittierende Schicht besteht in der Regel aus InGaN, deren blaues Licht vom Leuchtstoff teilweise in längerwelliges Licht umgewandelt wird. Die Lichtfarbe der LED ist auch zumindest teilweise von der Schichtdicke des Leuchtstoffs abhängig.

White light can be emitted with light-emitting diodes, e.g. B. can be generated by the following processes for additive color mixing:

1. a) Different light-emitting diodes, e.g. B. can be used in one and the same component. Blue light-emitting diodes are combined with yellow ones or with red and green ones in such a way that their light mixes well and appears white.
2. b) It is a blue-emitting LED or a UV LED with a phosphor z. B. combined in the form of a luminescent layer of a photoluminescent material or a luminescent dye. In this way, short-wave, higher-energy light, in particular blue light or ultraviolet radiation, can be converted into longer-wave light. For example, a blue LED is combined with cerium-doped yttrium aluminum garnet powder. Since blue LEDs have the highest efficiency, while UV LEDs have less than half, this is the most economical method of generating white light using LEDs, but with the disadvantage of a blue cast in the white light. The ultraviolet portion that blue LEDs emit at the short-wave end of their radiation spectrum is also largely converted into yellowish light by the luminescence layer. In a manufacturing process for white LEDs z. B. gallium nitride epitaxially on a carrier z. B. applied from sapphire or silicon. This creates the first layer of the GaN semiconductor crystal. The light-emitting layer usually consists of InGaN, whose blue light is partially converted into longer-wave light by the phosphor. The light color of the LED is also dependent, at least in part, on the layer thickness of the phosphor.

The above methods for generating white light are z. B. in the WO 2007/017049 A1 described. through the WO 2007/017049 A1 photonic material with regularly arranged cavities is also known, containing at least one colorant, the wall material of the photonic material having dielectric properties and as such is essentially non-absorbing for the wavelength of an absorption band of the respective colorant and is essentially transparent for the wavelength of a through the absorption wavelength excitable emission of the colorant and the cavities are designed such that radiation of the wavelength of the weak absorption band of the colorant is stored in the photonic material. Radiation is preferably selected from the wavelength range from 250 nm to 500 nm and stored in the photonic material, the radiation preferably being selected from the wavelength range from 380 nm to 480 nm and particularly preferably from an indium gallium nitride, in particular of the formula In _j Ga _j Al _k N, where 0<i, 0<j, 0<k, and i+j+k=1. at the colorant is an emitter for radiation in the range from 550 nm to 700 nm, which is preferably a rare earth compound doped with europium, samarium, terbium or praseodymium, preferably with triply positively charged europium ions. The colorant is in nanoparticulate form, preferably with an average particle size of less than 50 nm (hydraulic diameter determined by dynamic light scattering).

In general, such solid substances are referred to as phosphors that produce visible light through excitation with short-wave light up to the ultraviolet range or electron bombardment. Luminescent substances are often inorganic, crystalline substances which, through the targeted introduction of imperfections in the crystal structure, produce a technically usable light yield. Purity levels of the starting materials of up to 99.9999% are required. The phosphors are mostly based on oxides or sulfides such as zinc oxide, zinc sulfide, zinc cadmium sulfide and zinc sulfide selenide, and silicates such as willemite and zinc beryllium silicate. Zinc sulphide is also used in self-illuminating radioactive fluorescent paints. The doping element determines the luminous color (ZnS:Mn → orange-red; ZnS:Ag → blue; ZnS:Cu → green; ZnS:Ln → red to blue-green depending on the lanthanide). Parameters such as the color of the fluorescence and phosphorescence, the afterglow and the efficiency of the energy reproduction depend not only on the materials used, but also on their processing such as annealing, grinding, quenching and atmospheric influences during these processes.

wobei A ausgewählt wird aus der Gruppe bestehend aus Sr, Ca, Ba und Kombinationen davon; A' ausgewählt wird aus der Gruppe bestehend aus Mg, Zn und Kombinationen davon; Ln ein Ion/Ionen ist von wenigstens einem Element ausgewählt aus der Gruppe bestehend aus Nd, Dy, Ho, Tm, La, Ce, Er, Pr, Bi, Sm, Sn, Y, Lu, Ga, Sb, Tb, Mn und Pb; M ausgewählt wird aus der Gruppe bestehend aus Cl-, F-, B-, I- und Kombinationen davon; N ausgewählt wird aus der Gruppe bestehend aus Li+, Na+, K+, Ag+ und Kombinationen davon; a, b, c, x, y, z und δ molare Koeffizienten sind; 1,0 ≤ a ≤ 5,0; 0 ≤ b ≤ 2,0; 0,5 ≤ c ≤ 2,5; 0,001 ≤ x ≤ 0,2; 0 ≤ y ≤ 0,5; 0 < z < 0,5; 0 < δ < 0,2; und wobei 1 ≤ (a+b)/c ≤ 4; und dass bei Erregung eines lichtemittierenden Elements als Erregungslichtquelle mit einem Emissionsspektrum im Bereich von UV-Licht bis zu Blaulicht von 240 nm bis 475 nm der Leuchtstoff wenigstens einen Teil des Lichts von der Erregungslichtquelle absorbiert und so ein Emissionsspektrum erzeugt, welches wenigstens zwei Maxima im Bereich von 370 nm bis 760 nm aufweist, wobei die Emissionen sich verbinden, so dass Weißlicht entsteht. Dabei wird der Leuchtstoff vorzugsweise von einer Erregungslichtquelle mit einem Emissionsmaximum im Bereich von UV-Licht bis zu Blau-Violett-Licht von 240 nm bis 455 nm erregt, wobei dieser Leuchtstoff ein Lichtemissionsspektrum mit zwei oder drei Maxima im Bereich von 370 nm bis 760 nm erzeugt.through the EP 2 062 960 A1 a phosphor, in particular a phosphor, is known which is used in lighting or in light-emitting devices including LEDs, the phosphor essentially comprising a silicate and an activator ion and having a main chemical composition which is expressed by the following formula: $$\text{aAO}\cdot \text{bA}\text{'}\text{O}\cdot {\text{cSiO}}_2:\text{xEu}\cdot \text{yLn}\cdot \text{zM}\cdot \mathrm{\delta }\text{N},$$

wherein A is selected from the group consisting of Sr, Ca, Ba, and combinations thereof; A' is selected from the group consisting of Mg, Zn, and combinations thereof; Ln is an ion/ions of at least one element selected from the group consisting of Nd, Dy, Ho, Tm, La, Ce, Er, Pr, Bi, Sm, Sn, Y, Lu, Ga, Sb, Tb, Mn and Pb; M is selected from the group consisting of Cl-, F-, B-, I-, and combinations thereof; N is selected from the group consisting of Li+, Na+, K+, Ag+, and combinations thereof; a, b, c, x, y, z and δ are molar coefficients; 1.0 ≤ a ≤ 5.0; 0 ≤ b ≤ 2.0; 0.5 ≤ c ≤ 2.5; 0.001≦x≦0.2; 0 ≤ y ≤ 0.5; 0<z<0.5;0<δ<0.2; and where 1 ≤ (a+b)/c ≤ 4; and that when a light-emitting element is excited as an excitation light source with an emission spectrum in the range from UV light to blue light from 240 nm to 475 nm, the phosphor absorbs at least part of the light from the excitation light source and thus produces an emission spectrum which has at least two maxima in the range from 370 nm to 760 nm, the emissions combining to produce white light. In this case, the phosphor is preferably excited by an excitation light source having an emission maximum in the range from UV light to blue-violet light from 240 nm to 455 nm, this phosphor having a light emission spectrum with two or three maxima in the range from 370 nm to 760 nm generated.

According to DIN 55943:2001-10 "Colourants - Terms", the term colorant is a collective designation for all coloring substances. DIN 55943 initially divides colorants into organic and inorganic colorants. Each of the two groups is divided into dyes and pigments. Pigments are coloring substances which, in contrast to dyes, are insoluble in the application medium. The substance in which the colorant is or will be incorporated is referred to as the application medium. In addition to the chemical structure, the properties of the pigments are also determined by their solid-state properties, e.g. B. crystal structure, crystal modification, particle size and particle size distribution. In order to address the material of a dye that has optical properties, the term particles of the dye in question is used below, even if these particles are molecules that are soluble in the application medium or are more complex chemical compounds.

Colorants specifically absorb a limited portion of visible white light and remit the unabsorbed portion of white light. The complementary color of the light perceived by an observer is absorbed by the colorant. The color absorption is based on conjugated double bonds and aromatic basic structures of the molecules. During absorption, conjugated electrons in the double bond system are raised to a higher energy state and the colorant molecule releases energy again through radiation in a different, in particular visible, wavelength or through heat radiation. The absorption range of a colorant can be influenced by changing functional groups on the aromatic compound, these groups acting as a nitro, sulfonic acid, dimethylamino or hyd roxy group can be formed. At the same time, this can also influence the chemical reactivity and the color properties. An NH ₂ group with its free pair of electrons has a color-deepening effect. Aromatics, ie aromatic compounds or chemical compounds with at least one aromatic basic body, are a class of substances in organic chemistry, which is characterized in that aromatic molecules have at least one ring system, which according to the Hückel rule in conjugated double bonds, free pairs of electrons or unoccupied p-orbitals contains a number of 4n+2 (n = 0, 1, 2, ...) delocalized electrons. This delocalization leads to a special bonding system in which it is not possible to distinguish between single and double bonds in the ring. In simple, symmetrical ring systems, such as B. in the case of benzene, all bonds are therefore identical. Compared to non-aromatic double bond systems, aromatics have less energy and are therefore less reactive. In particular, they do not tend towards addition reactions. The Hückel rule can be used to determine whether a chemical compound is an aromatic molecule. A cyclically conjugated molecule is particularly stable with [4n + 2] π electrons (an odd number of electron pairs; example: n = 1, [4x1 + 2 = 6], i.e. three electron pairs) and is referred to as an aromatic compound.

As already mentioned, the absorption of electromagnetic radiation raises the energy level of electrons in molecules or atoms. This means that a distance between electrons and the respective associated atomic nuclei is increased approximately. The energy required for this is the incident electromagnetic radiation, z. B. the light removed. Since these processes take place under quantum conditions, the absorption of electromagnetic radiation is not continuous, but only takes place in certain jumps that correspond to the energetic difference between the electrons before and after the absorption. This energy difference is inversely proportional to the absorbed wavelength of the incident light and thus determines the color in which the colorant appears.

The property of a substance to be a colorant is therefore based on its chemical structure. Molecules with σ-bonds absorb electromagnetic energy in the X-ray and UV range. Molecules with electrons in π bonds, i. H. in unsaturated bonds, on the other hand, are excited by electromagnetic waves (or photons) even at lower energies. Interactions of this kind in the long-wave UV and especially in the visible range of light trigger the color stimulus.

If there are several conjugated unsaturated bonds in a molecule, the π electrons can be "smeared", i. H. delocalize, which reduces the energetic distance between the excited state and the ground state and shifts an absorption or emission maximum in the direction of longer wavelengths. The longer the wavelength of the absorption range, the more such unsaturated bonds are conjugated.

There are organic and inorganic chromophores, i. H. color carrier. Organic chromophores consist of systems of conjugated double bonds such as carotene and/or large aromatic molecules such as methyl red. Inorganic chromophores are often found among the transition metals. Examples are vanadium, chromium, manganese, iron, cobalt, nickel and copper. Depending on the oxidation state and complex formation, these elements can show very different colors. The chromophore is the part of a colorant that is responsible for the basic presence of the color.

Chromophores are molecular structures whose vibrational properties can be significantly influenced by auxochromes (electron donors) and antiauxochromes (electron acceptors), which further shift and/or polarize the delocalized π-electrons of the chromophore. Auxochromes or anti-auxochromes increase resonance in the molecule by shifting electrons towards or away from a chromophoric group. For example, the absorption spectrum of a chromophore does not necessarily have to be in the visible range of the electromagnetic spectrum. However, if the chromophore is further modified by the mesomeric effect of a substituent, i. i.e. R. also its absorption spectrum.

So, chromophores are those basic structures that contain delocalizable electrons. The type of chromophores influences the hue of the colorant via their absorption maximum, while the frequency of the chromophores influences the color depth. The following molecular structures in particular act as chromophores: RC=CR; RN=NR; R-NO ₂ ; RC=O; RC=NH; RN=O

1. a) Auxochrome: R-OH; R-O-R'; R-NH₂; R-NH-R'; R-NHCO-R'
2. b) Antiauxochrome: R₂-C=O; R-NO₂; R-CHO, R-COOH; R-SO₃H; R-C=NR'

The following functional groups in particular act as auxochromes or antiauxochromes:

1. a) auxochromes: R-OH; R0-R'; R-NH ₂ ; R-NH-R';R-NHCO-R'
2. b) antiauxochromes: R ₂ -C=O; R-NO ₂ ; R-CHO, R-COOH; R-SO ₃ H; RC=NR'

1. a) im Molekülaufbau des Farbmittels selbst,
2. b) in seinen Molekül- und Atomschwingungen,
3. c) in der Konzentration des Farbmittels sowie
4. d) in seinem Bindungszustand am oder im jeweiligen Anwendungsmedium.

The color properties of colorants are thus justified

1. a) in the molecular structure of the colorant itself,
2. b) in its molecular and atomic vibrations,
3. c) in the concentration of the colorant and
4. d) in its binding state on or in the respective application medium.

The manner in which the colorant is bound is determined by z. B. designed as a substrate or carrier application medium. The binding of the colorant to a solid or the distribution of a dye in a solution can change the hue, which is used in solvatochromism. Solvatochromism refers to the influence of a solvent on the color of a dye. The discernible color of the solution is based on the interactions of the dye with the solvent molecules on the one hand and on the mutual interactions of the solvent molecules on the other hand.

When used, functional colorants fulfill a specially defined function that is not solely based on an aesthetic coloring. So e.g. B. an indicator dye a functional colorant.

1. a) Licht bei einer bestimmten Wellenlänge absorbieren und das absorbierte Licht in Wärme umwandeln,
2. b) Licht bei einer anderen Wellenlänge wieder emittieren, z. B. als phosphoreszierende Marker oder z. B. in Form von Fluoreszenz oder Chemilumineszenz,
3. c) die Polarisationsrichtung des Lichts verändern, z. B. bei der Frequenzverdoppelung oder als optische Schalter,
4. d) elektrische Phänomene bewirken,
5. e) fotochemische Prozesse ermöglichen.

From the knowledge of the color absorption of aromatic or polyunsaturated compounds according to the Hückel rule, one can produce special colorants that

1. a) absorb light at a specific wavelength and convert the absorbed light into heat,
2. b) Re-emit light at a different wavelength, e.g. B. as phosphorescent markers or z. B. in the form of fluorescence or chemiluminescence,
3. c) change the direction of polarization of the light, e.g. B. in frequency doubling or as optical switches,
4. d) cause electrical phenomena,
5. e) enable photochemical processes.

Printing inks used in printing technology are an application medium for colorants that is of particular interest below. Printing inks are mixtures of substances containing colorants that are transferred to a substrate, in particular with the aid of a printing form, and form a layer there that dries. Printing inks are suitable for coloring surfaces in technical and industrial processes in such a way that images and text are displayed. Printing inks consist of extremely finely divided pigments, binders and organic solvents. Black ink contains carbon black pigments, especially carbon black. Colored pigments are extracted from minerals or chemically produced.

The printing ink should realize a required hue on a printing material, with the hue being able to be specified as a color location in a color space. The optical properties of a printing ink depend on the printing process used to apply the ink, the substrate, the location of the viewer and the light source under which the printed product is viewed.

The mechanical properties of printing inks are also called rheological properties. Printing inks for printing processes in which the ink is applied by rollers, e.g. B. in offset printing, letterpress or gravure printing, require good transport of the ink over the ink rollers and low aerosol formation. Ink transport is determined by the tack of the printing ink. Tack is the force required to separate an ink film. It is a complex relationship between viscosity, cohesion and adhesion and is measured as tack in ink testing. Aerosol formation is the formation of ink mist and filaments of ink at high print speeds. These aerosols are undesirable. The formation of aerosols is strongly dependent on the temperature, since it correlates directly with the viscosity.

1. a) Farbmitteln, d. h. aus Pigmenten oder Farbstoffen, für die Farbigkeit,
2. b) Bindemitteln, hauptsächlich aus Harzen (Festharze, Alkydharze), um die Farbmittel auf dem Bedruckstoff zu befestigen,
3. c) Hilfsstoffen zum Einstellen der rheologischen Eigenschaften, z. B. zur Beeinflussung von Trocknung, Glanz oder Oberflächenhärte.

Printing inks consist of:

1. a) colorants, i.e. made of pigments or dyes, for the color,
2. b) binders, mainly made of resins (solid resins, alkyd resins) to attach the colorants to the substrate,
3. c) auxiliaries for adjusting the rheological properties, e.g. B. to influence drying, gloss or surface hardness.

Since the layer thicknesses of the printing inks applied to the printing material are very small (typically about 1 μm to 8 μm, preferably 0.7 μm to 2.5 μm in offset printing), pigments with strong color strength are used in particular. Most printing inks consist of a dispersion (actually: suspension) of pigments in a carrier fluid and are therefore a heterogeneous mixture of substances consisting of a liquid and finely distributed solids.

Pigments are organic, inorganic or synthetic crystalline powders. Organic pigments are extracted from petroleum and used to produce cyan, magenta, yellow and special inks. Organic pigments are not very temperature stable. Inorganic pigments are mostly special carbon blacks for black colors and titanium dioxide for opaque white. Carbon black is inorganic by definition. Most inorganic pigments are characterized by the fact that they do not react chemically with the oxygen in the air, are therefore extremely resistant to aging and retain their color for practically any length of time. Finely ground metallic pigments are used for metallic effects. Silver effects are achieved with aluminum bronze. Gold effects can be achieved by using brass bronze or aluminum bronze with yellow/orange pigment. Fluorescent colors are created by UV-active pigments in the printing ink. Pigments are insoluble in the printing ink and mostly harmless to health. Radioactive illuminants are not counted among the pigments, although they are insoluble in the application medium.

They are self-luminous and are not emitted by UV radiation or daylight, but by radioactive excitation.

Dyes enable purer colors than pigments because they reflect light with a narrower spectrum. Dyes are soluble in water, alcohol and fats on a molecular basis. However, dyes tend to fade under the influence of UV radiation, so they are not as colourfast as pigments. In addition, most dyes are toxic and therefore unsuitable for coloring everyday objects.

The pigments of the printing ink are dispersed in the binder, i. H. finely divided. The binder enables good wetting of the individual pigments and prevents pigments from sticking together to form agglomerates. During printing, the binders stick the printing ink to the substrate and determine the viscosity.

A typical offset printing ink contains between 12% and 18% pigments.

Pigments typically arise in the form of primary particles. The primary particles can grow together over their surfaces to form aggregates. One speaks of agglomerates when primary particles and/or aggregates are connected via their respective corners and/or edges. The pigment agglomerates are broken up by a dispersing process (dispersion) during incorporation of the pigments into the relevant application medium. Smaller agglomerates, aggregates and primary particles are formed. If present, these are wetted by a dispersing medium. Ideally, they are distributed statistically across the application medium.

For purposes of safety engineering, e.g. B. by the WO 00/59731 A1 and the WO 2012/083469 A1 Color pigments have become known that belong to the substance class of retinal proteins. An important representative of the retinal proteins is bacteriorhodopsin (BR). The BR protein consists of 248 amino acids, which, arranged in seven approximately parallel alpha helices, run through a cell membrane and form a pore. Inside this pore is a retinal molecule bound to the protein. Retinal is the chromophore of the molecule and is linked to the amine function of the amino acid Lys216 via an imine bond, commonly referred to in this context as a Schiff base. Under physiological conditions, the chromophore exists only as the all-trans and 13-cis isomer. The isomerization takes place under the action of light. BR forms two-dimensional crystalline areas in the cell membrane of Halobacterium salinarum, assembled into trimers. These areas, up to five micrometers in size, in which BR trimers are present in a two-dimensional hexagonal arrangement in the lipid bilayer, are called purple membrane (PM). The embedding of the BR in the purple membrane leads to a remarkable stability of the protein against about physico-chemical influences. This preserves the color and photochemical activity of the PM in the presence of oxygen and in the dry state.

BR can be thought of as a light energy powered molecular machine pumping protons. Initiated by the light-induced isomerization of the chromophore and driven by changes in the proton affinities of amino acid functions, protons are shifted from a cytoplasmic to an extracellular side through the pore of the protein in a multistep process. The directional proton shift is triggered by the isomerization of the retinal chromophore as a result of light absorption. The chromophore exists as a mixture of all-trans and 13-cis retinal in the unexposed state, only in the 13-cis configuration after exposure. Due to the embedding of the chromophore, this results in structural changes in the protein, which directly affects the initially protonated state of the Schiff base. After the isomerization, this proton is in an energetically unfavorable environment and is released to the direct interaction partner of the Schiff base, Asp85, in the extracellular direction. This is followed by a sequence of four further unidirectional proton shifts before the protein is finally restored to its original state and a new cycle can be run through. This light-driven pumping of protons is linked to a cyclic sequence of spectroscopically distinguishable states of the protein. This sequence is called the photocycle. Photocycling upon exposure is associated with a reversible color change from purple (B-state, absorption maximum 570 nm) to yellow (M-state, absorption maximum 410 nm).

In the aforementioned WO 00/59731 A1 a method for ensuring the authenticity of objects has now been described in which a photochromic preparation in the form of an ink containing bacteriorhodopsin as a photochromic component is applied to the object, the irradiation of this photochromic preparation with light in the visible wavelength range leading to a change in state leads, which is detectable for the purpose of authenticity testing.

An intensely colored liquid is used as the ink for e.g. B. in word processing or goods labeling. Ink consists of a solution or dispersion of colorants in water or some other solvent and contains little or no binder. Inks without binders are therefore not printing inks. There are different types of ink, e.g. B. Inks with soluble colorants or with insoluble colorants, water-soluble inks, solvent-based inks or pigmented inks, whereby pigments, in contrast to dyes, cannot be chemically dissolved in the application medium. While pigments have their own characteristic color, the color of a dissolved dye can depend on the solvent used, which can result in the ink having a different color than the dried ink deposit.

through the WO 2012/083469 A1 a method for checking the authenticity of a security feature, in particular on a security document, is known, with the security feature showing a change in the visible range when a flash of light is excited, with at least a first image of the non-excited security feature being recorded with a mobile phone, with the mobile phone having a camera with an integrated flash function, wherein at least a second image of the security feature excited using the flash function is recorded with the same mobile phone, wherein the sequence of the two aforementioned recordings can also be reversed. An authentication check is then carried out in the mobile phone from the at least two images using a suitable data processing program on the mobile phone and the result of this check is output via a display or an acoustic interface on the mobile phone.

In photography, a flashlight is understood to be a lighting device that provides for an object illumination at the moment of recording by means of a flash of light. An electronic flash unit is a z. B. in a data acquisition device or in an image recording device, z. B. in a camera or in a mobile phone, z. B. Flash unit integrated in a smartphone, which works with a flash lamp based on a gas discharge tube. Electron flash devices mostly work with xenon-filled flash tubes. When the flash unit is triggered, a capacitor previously charged to a few 100 volts, e.g. B. a cylindrical electrolytic capacitor or a plate-shaped flat polymer capacitor discharged, whereby a very short, bright gas discharge is generated inside the flash tube. A typical lighting duration of this flash is between about 1/300 and 1/40,000 second, depending on the power and control. The emitted spectral range of a xenon-filled flash tube extends continuously from the ultraviolet range through the visible range to the infrared range, depending on the design of the Flash tube a particularly high radiation intensity in the wavelength range z. B. between 300 nm and 500 nm or between 880 nm and 1000 nm.

Alternatively, LEDs, preferably power LEDs, are used as flash units in mobile phones or smartphones, e.g. B. a flashing LED of the Luxeon product range from Philips Lumileds Lighting Company, San Jose, California, USA, or the Oslux or Ceramos product range, each from OSRAM Opto Semiconductors GmbH, Regensburg, DE. These flashlight LEDs have i. i.e. R. two spectral maxima, namely at about 440 nm (blue) and at about 570 nm (yellow), resulting in at least approximately white light for an observer in the additive color mixture.

through the WO 2013/054290 A1 discloses a security element or security document having a carrier and at least one first feature applied to the carrier and having a dynamic effect, the dynamic effect occurring as a result of excitation by illumination having a selected wavelength or wavelength band and generating an optical spectral response, wherein dynamically changing the optical spectral response during excitation by means of illumination over an observable period of time between multiple color appearances, wherein the first feature having the dynamic effect is located in a region of the substrate that is proximate to an adjacent feature mounted on the substrate, wherein the adjacent feature has a color impression that is selected in such a way that this color impression reinforces and/or complements at least one color impression of the first feature with the dynamic effect. This dynamic effect is preferably caused by a pigment, as z. B. in the WO 2007/005354 A2 describes which pigment has more than one color impression under uniform, sustained exposure to electromagnetic radiation. According to the WO 2007/005354 A2 Such a pigment comprises a core having a carrier substance and either a fluorescent material or a phosphorescent material, the core having a substantially spherical shape, with a shell surrounding the core being provided, the shell containing photochromic material which in the radiation a first light source has a first optical property and in radiation from a second light source has a second optical property, the second light source containing a set of wavelengths not sufficiently present in the first light source, the second optical property being one of the fluorescent material or attenuates radiation emitted by the phosphorescent material. The first optical property is z. B. substantially transparent. The second light source includes z. B. Ultraviolet wavelengths.

In the EP 2 637 145 A1 a method for the authentication and/or identification of a document or an article is proposed in which circularly polarizing liquid crystals are contained in a printing ink in a stochastic distribution, ie random distribution, with the authenticity of this document or article is checked. Such liquid crystals have a cholesteric phase with a nematic order with a continuously rotating preferential orientation. This results in a helical superstructure with a periodicity of typically a few 100 nm. The optical medium twisted in this way acts as a one-dimensional photonic crystal with a photonic band gap for circularly polarized light with the same handedness as the helical order. Cholesteric liquid crystal films therefore show selective reflection of circularly polarized light. In contrast to the reflection on metallic or dielectric mirrors, the handedness of the circular polarization is preserved in cholesteric liquid crystal films.

through the WO 2004/070667 A2 a method for producing security identifiers is known, in which the security identifier contains a random pattern. The security mark is z. B. formed by the reflective surface of each object to be marked. Alternatively, the safety mark of particles, e.g. B. colored particles, pigments, effect pigments, sand, dust, crystals (z. B. salt crystals of different colors), ferromagnetic, magnetizable, permanently magnetic, fluorescent, phosphorescent, iridescent, opalescent or radioactive particles formed. The random pattern, which is in particular machine-readable, is applied to a product or a label. A fingerprint is extracted from a read random pattern in the form of a data set that contains the individual characteristics of the pattern. This fingerprint is saved individually for each security identifier. During authentication, the fingerprint is extracted again and the match with the stored fingerprint is checked.

Organic and inorganic, of which particularly inorganic fluorescent particles are suitable as particles in security markings, such as are available, for example, from the company Leuchtstoffwerk Breitungen GmbH (98597 Breitungen, www.glühstoffwerk.com). Also suitable are crystals, e.g. B. platelet-shaped crystals, liquid crystals, reflective pigments from at least two layers with different refractory index, effect pigments (interference pigments, pearlescent and metallic luster pigments). Effect pigments are available, for example, on the one hand under the trade names Iriodin®/Afflair® and Colourstream® from Merck KGaA, Darmstadt, and on the other hand under the trade name Helicone® from Wacker Chemie, Burghausen. A particular advantage of reflecting particles is the fact that a) they are, in contrast to fluorescent particles, subject to almost no wear and tear due to light and b) different random patterns arise depending on the viewing and illumination angle. Such changes arise e.g. For example, when looking at the effect pigments, each individual pigment acts like a microscopic mirror for light of a certain wavelength, which reflects this light in its random spatial orientation, resulting in three-dimensional random patterns. The particles used have, for example, a diameter between 0.1 µm and 1 µm, between 1 µm and 10 µm, between 10 µm and 80 µm, between 80 µm and 150 µm or between 150 µm and 2000 µm, and each have a thickness of up to 50 μm, preferably up to 10 μm, particularly preferably up to 3 μm. The particles are preferably introduced into a matrix (carrier). The resulting mixture is used to coat objects. Paints and varnishes are suitable as a matrix, preferably water, solvent, powder, UV varnishes, epoxy resins, plastics (e.g. polyethylene), ethyl acetate and comparable materials, paraffins, waxes and waxy coatings (e.g. Flexane ). The particles can also be incorporated into printing inks. Printing inks are preferably used for screen, gravure, flexographic and offset printing, the thickness of the ink layer being <=20 μm, preferably <=10 μm, particularly preferably <=5 μm, very particularly preferably <=3 μm. The concentration in percent by weight of the particles in the matrix is between 0.01% and 30%, preferably between 0.01% and 1%, between 1% and 10%, and between 10% and 30%, particularly preferably between 0.01 % and 1% and between 10% and 15%.

A stochastic distribution, ie a random distribution of optically active particles in a layer with readable information for authentication and/or identification of a security feature is z. B. also in the WO 2006/078220 A1 described, these particles having a length extension preferably in the range between 10 nm and 500 microns.

Also describes the U.S. 2001/0010333 A1 Random pattern with optically detectable colored fibers or threads to make an object unique and thus, after illumination with a light source, by detecting the optical pattern of the object, e.g. B. using a photo sensor to make this object identifiable.

Also the WO 2007/131043 A2 discloses an object to be authenticated having a substrate and a mark on the substrate, the mark comprising a luminescent material, the material being distributed in a random pattern, the luminescent material exhibiting photoluminescence with a quantum efficiency of at least 10 percent. The marking has particles with the luminescent material, which particles are distributed in the random pattern. The particles have a size in the nanometer range.

Also the WO 2013/144645 A1 relates to a method of creating a mark to distinguish between genuine and counterfeit goods, wherein at least one code is applied to a surface, the code being generated at random so that the code has a unique pattern when it is of a particular type subjected to stimulus. A large number of codes can also be applied. The unique pattern results z. B. from the fact that the position of elements of the coding is only visible under UV radiation, that the visible color of the elements of the coding is visible only under UV radiation, or that the position of the elements of the coding and the visible color of the elements of the Coding visible under IR radiation.

Furthermore, from the WO 2010/023243 A1 an identification feature for identifying an object is known, which comprises at least two identification elements, with at least a first of the identification elements being provided by at least one defined, delimited surface with a defined diffractive surface structure, which can be recognized by light irradiation in the visual range, and with at least a second of the identification elements is provided within an optical detection field that at least partially detects the defined limited surface of the first identification element, wherein the first and the second identification element are each an integral part of the object. The at least one second identification element is preferably given by a random structure in a surface of the second identification element or of the object, the random structure of the second identification element z. B. is integrated in the defined diffractive surface structure of the first identification element. The at least one second identification element is z. B. not visible bar. To identify the object, the position at which the at least one second identification element is arranged relative to the at least one first identification element is stored. Furthermore, identification information that is unique to the at least one second identification element is stored. For identification, an image of the first identification element is compared with the stored data.

through the DE 28 29 778 A1 is a mark of value such as B. a credit or ID card with individual features are known, these features being present on or in the card in a random distribution and physically scannable, with optical means being used to generate a reproducible scanning size corresponding to the random distribution of the features on or in the card scannable track that contrasts with the environment is provided, the optical properties of which are modulated by the random distribution of the features that are congruent with the track. The characteristics are e.g. B. absorbing and / or scattering structures in one or more levels of the stamp, the structures z. B. deposits in the layers of the stamp. The line has z. B. present in random distribution fluorescent particles that vary in size and in their mutual distance from each other.

through the DE 196 11 383 A1 discloses a data carrier with an optically variable security element arranged on its surface, with the security element conveying a different optical impression when viewed from at least two angles, with the data carrier being provided with a background layer at least in a partial area, which has at least one authenticity feature, and with the security element at least partially overlaps this background layer, the background layer being arranged in such a way that it is not completely covered by the security element, at least in one direction. The underground layer contains z. B. at least one authenticity feature from the group of luminescent, metallic, magnetic, electrically conductive substances or optically variable pigments. In the underground layer z. B. visually and / or machine-readable information.

through the WO 2013/034471 A1 a device for recognizing a document is known, the document having a security feature with wavelength conversion properties, with: a) a light generating device which is designed to illuminate the security feature with excitation light to emit light; b) an image recording device, which is designed to record a light emitted by the security feature in response to the excitation light in order to obtain an emission recording, wherein the image recording device is also designed to record light emitted by the security feature in response to a reference light in order to obtain a reference recording ; and c) a processor configured to recognize the document based on the emission record and the reference record. The reference light z. B. white light, in particular daylight, or the light generating device is designed to generate the reference light, in particular as a continuous light during the reference recording, or the light generating device is designed to generate reference light pulses as the reference light during the reference recording. For example, the processor is B. designed in such a way to compare the emission recording with the reference recording in order to obtain a comparison result and to recognize the document on the basis of the comparison result, wherein the reference light has in particular a predetermined wavelength, and wherein the processor is designed to detect a wavelength difference between the predetermined wavelength and at least one wavelength of the emission light, or a time course of the wavelength of the emission light with respect to the predetermined wavelength, in particular a time course of a wavelength amplitude or wavelength differences, in order to obtain the comparison result. The device is preferably a mobile communication device, in particular a smartphone, the light generating device being an LED flash unit of the mobile communication device, and the image recording device being a digital camera of the mobile communication device. Alternatively or additionally, the device comprises a transceiver unit which is designed to send the emission recording or the reference recording or a comparison result of a comparison of the emission recording with the reference recording via a communication network to a remote server for the purpose of document recognition and to receive a result of the document recognition in response thereto. The device comprises a control device for controlling the light generating device in order to generate excitation light and/or reference light. The control device can be programmed and designed, for example, to execute a computer program, which can be application software (APP). The security feature, which has wavelength conversion properties, can comprise, for example, silicate pigments, in particular silicate phosphorus pigments, silicate, sulfide, nitride, YAG, TAG, thiogallate phosphorus pigments, which are added to a printing ink. Such a safe The safety feature emits a color-shifted light spectrum in response to excitation with blue light with a wavelength of about 400 nm, which light spectrum can have, for example, green, yellow, orange and/or red light. An LED can therefore be used to excite such a security feature, the light emission spectrum of which includes blue light in a wavelength range between 390 nm and 470 nm. Document recognition can therefore be performed using an ordinary smartphone equipped with an LED flash unit. The excitation light can therefore include or be blue light in a wavelength range from 390 nm to 470 nm, preferably in a wavelength range between 430 nm and 460 nm. For this purpose, the light-generating device can comprise an LED for generating continuous light or flashing light or pulsed light. In response to the excitation with the excitation light, the security feature is excited to emit light. Due to the wavelength conversion properties of the security feature, which can be realized, for example, by using a silicate compound such as silicate phosphorus, the security feature emits light having a wavelength that differs from a wavelength of the excitation light. The emission recording thus contains information about a wavelength spectrum emitted by the security feature in response to the excitation light. In analogy to this, the reference recording includes information about a reference wavelength spectrum, which can be emitted by the security feature in response to the reference light.

through the EP 2 698 404 A1 a group of identification information is known for verifying authenticity and identity, the identification information being identifiable by magnification or magnification, the group including a first information element and a second information element, the second information element not being magnified in any way or gain can be identified with which the first information item is identified.

through the DE 103 46 634 A1 discloses a document of value, in particular a banknote, with a document of value substrate and at least three different feature substances for checking the document of value, the document of value having a first feature substance, with a second and third feature substance being applied together to the document of value substrate in a printing ink, with the second feature substance is formed by a luminescent substance and the third feature substance is formed by a material absorbing in a specific spectral range.

through the U.S. 2006/0011504 A1 an object is known which is provided with an individual identification means for identification, the identification means being a random identification means specific to the object. The random identifier is applied to a label. The label is preferably colored and bears a random distribution of luminophores. In addition, a serial number is provided on the object, which on the one hand can be designed as a simple print with ink or the like or alternatively itself is the carrier of the random identifier. The serial number can have a distribution of luminophores in the ink. The distribution of the luminophores is limited to the area printed with the ink.

In the U.S. 2004/0200902 A1 various two-dimensional machine-readable codes are named, whereby the relevant code is made of fluorescent ink and can be read after being irradiated with UV light. A QR code is mentioned as an example.

1. a) Vorbehandeln der Oberfläche des Artikels;
2. b) Einfärben der Oberfläche des Artikels mit einer Farbstofflösung, die einen organischen Farbstoff und ein organisches Lösungsmittel enthält;
3. c) Reinigen und Trocknen der Oberfläche des Artikels;
4. d) Gravieren durch zumindest teilweises Abtragen der Oberfläche des Artikels.

through the WO 2013/060831 A2 a method for marking an article comprising a shape memory polymer (SGP) with a visually and/or machine-readable graphic element on the surface of the article is known for the purposes of information coding and as a security feature, comprising the following steps:

1. a) pretreating the surface of the article;
2. b) staining the surface of the article with a dye solution containing an organic dye and an organic solvent;
3. c) cleaning and drying the surface of the article;
4. d) Engraving by at least partially removing the surface of the article.

Shape memory polymers (SMP) are generally used to refer to plastics that appear to be able to "remember" their previous external shape after reshaping and therefore have a shape memory. In order to recall the former form, the FGP must be exposed to a stimulus. This pen mulus can consist, for example, in the supply of heat by directly or indirectly heating the SMP in question. The SMP can be heated directly from the outside by hot air, by IR radiation, for example by exposure to sunlight or the air flow of a hot fan, or by direct contact with a heat storage medium, such as a previously heated fluid. For example, the heat can be supplied by immersion in warm water.

In an abstract of the document "Security printing of covert quick response codes using upconverting nanoparticle inks" by Jeevan, accessed on April 16, 2014 at the Internet address http://iopscience.iop.org/0957-4484/23/39/395201/cites M Meruga et al Published by the Institute of Physics (IOP) at the University of the State of South Dakota and the South Dakota School of Mines and Technology on September 11, 2012 in IOP Publishing's Journal Nanotechnology, Volume 23, #395201, doi :10.1088/0957-4484/23/39/395201 describes a Quick Response (QR) code printed on a carrier material, this QR code is not visible under normal daylight conditions but is visible when exposed to a radiation source from the near Infrared range is readable, whereby the QR code made visible can then be captured by a camera of a smartphone. This QR code is used e.g. B. used to check the authenticity of banknotes, (value) documents or objects. A microscopic message can be incorporated into the QR code, e.g. B. can only be read with a microscope. The QR code is generated using a CAD system. The QR code is z. B. from a mixture of β-NaYF ₄ nanoparticles with lanthanides, z. B. Yb ³⁺ /Er ³⁺ and/or Yb ³⁺ /Tm ³⁺ , and green and blue fluorescent inks. The term lanthanides refers to the chemical element lanthanum and the 14 elements that follow lanthanum in the periodic table: cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium. All lanthanides are silvery, lustrous, relatively soft and reactive metals and are part of the rare earth group of metals.

The QR code described in the aforementioned abstract is printed on the carrier material in a direct printing process using an aerosol jet printer. Details of an aerosol jet printer are e.g. B. in the WO 2006/065978 A2 described. An aerosol jet printer first atomizes a printing ink with a viscosity between 1 cP and 1,000 cP into fine droplets with a size of 1 µm to 5 µm, preferably from 1 µm to 2 µm, and introduces these droplets into a first gas stream, this first gas flow transports the printing ink aerosolized in this way to a print head. A second gas flow arranged in a ring around the first gas flow is provided on the print head, by means of which the first gas flow transporting the aerosolized printing ink is reduced to a diameter of z. B. is collimated less than 10 microns. Both gas streams leave a nozzle of the print head directed towards a substrate at high speed and transfer the fine droplets of printing ink to the nozzle of the print head at a distance of z. B. 1 mm to 5 mm arranged printing material. Such an aerosol jet printer achieves a resolution of less than 10 μm, ie more than 2,500 dpi. An aerosol jet printer differs from an inkjet printer in the way it works and in its structure. Differences to an inkjet printer exist e.g. B. that the size of an ejected from an inkjet printer drop of ink z. B. at about 30 microns and the volume of a drop of ink ejected from an inkjet printer is about two hundred times larger than in an aerosol jet printer. Also, an inkjet printer typically uses ink with a viscosity between 8 cP and 12 cP, which means a significantly more limited range compared to an aerosol jet printer.

A code is an agreement on a set of characters or signifiers for the purpose of exchanging information. The characters or carriers of meaning of a code can be visually readable or haptically detectable or not directly usable for humans, but readable by means of a technical device, i. H. be machine readable. A code is e.g. B. also a visually readable or haptically detectable font, since a font represents a sign system for the preservation and transmission of coded information. The characters of a font can be z. B. each be an alphanumeric character or another character. The carriers of meaning agreed upon for a certain code are e.g. B. in each case a pictogram depicting something material or an ideogram representing an abstract concept.

In merchandise management or logistics, various machine-readable, in particular optoelectronically readable, e.g. B. with a CCD camera or with a CMOS camera or with a scanner detectable codes, z. B. barcodes used, using which each piece of information z. B. about a product in a sequence of different characters, z. B. Black and white stripes ("lines") of different widths are displayed. Two-dimensional codes are referred to as 2D codes or 2D barcodes, which consist of bars or dots of different widths and gaps in between with poss extremely high contrast. In contrast to the one-dimensional barcodes, the data in a 2D code is not only encoded in one direction (one-dimensional), but rather in a matrix in an area over two dimensions. Examples of a 2D code are the DataMatrix code defined in the international standard ISO/IEC 16022 or the QR code according to ISO/IEC 18004 or the MaxiCode developed by UPS for quick identification, tracking and sorting of packages or the standard Aztec code specified in ISO/IEC 24778.

The two-dimensional QR code consists of a rectangular, mostly square pixel pattern, with the individual pixels or symbol elements consisting of contrasting, preferably white and black, squares and a z. B. with a mathematical algorithm encoded information content thus represent binary. A QR code contains at least 21×21 and a maximum of 177×177 symbol elements. A QR code can be read using a smartphone with a camera, in particular with a semiconductor camera, and with a program designed as a “QR code reader”, i. H. a so-called APP, readable, the reading i. i.e. R. omnidirectional is possible. The reading is in particular an image interpretation based on the detected contrast values. A QR code arranged on a carrier contains markings at defined points to identify its position and alignment. Information on the resolution and the version of the pixel pattern as well as on the data format of the data stored in the pixel pattern and for its error correction is also stored at other defined points in the pixel pattern, with an error correction level selected from a set of permissible error correction levels during the generation of the relevant QR code is determined. Four error correction levels L, M, Q and H, which determine an error tolerance, were defined, according to which 7% (level L), 15%, 25% or 30% (level H), e.g. B. Unreadable data due to destruction or faulty production can be recovered. Up to 7,089 numbers or 4,296 letters can be encoded per QR code.

Referring to an arrangement of characters or signifiers belonging to a code, pixels are picture elements or picture elements, each of which is assigned a color value in a raster graphic, with a raster graphic representing an image in the form of computer-readable data. A raster graphic consists of a grid arrangement of pixels.

Contrast is a difference between light and dark areas or colors of an image. The contrast is a distinguishing feature for a brightness profile of an image or at least between two pixels. The contrast range or dynamic describes the difference in intensity between the brightest and darkest point of an image. The contrast is defined by the maximum luminance and minimum luminance present in the image or between the pixels. According to the Weber-Fechner law, different intensities of the respective luminance are not perceived linearly by the human eye, but logarithmically. So that a visual or an optical system, e.g. B. an eye or a camera can perceive an object, this object must be large enough and have a sufficiently high contrast. This is understood to mean the limit of visibility that is reached when objects that are viewed and z. B. on the retina in the human eye or on an image sensor in a camera, can no longer be distinguished from the surrounding luminance as contour and contrast. This means that the recognisability of objects essentially depends on the ability of the visual or optical system to perceive differences in brightness. A certain minimum contrast is therefore required to perceive an object, which is higher in weak ambient light conditions than in brighter light.

1. a) Mindestleuchtdichte
2. b) Mindestkontrast
3. c) Mindestgröße
4. d) Mindestdarbietungsdauer

In principle, an object can only be perceived optically if the object in question fulfills the following four minimum requirements with regard to the visual or optical system capturing this object at the time of image capture or image recording:

1. a) minimum luminance
2. b) minimum contrast
3. c) minimum size
4. d) Minimum performance time

The invention is based on the object of creating an identification feature with a plurality of identification elements arranged in a defined, limited area for identifying an object.

The object is achieved according to the invention by the features of claim 1. Advantageous configurations result from the dependent claims.

The advantages that can be achieved with the invention consist in particular in the fact that the identification feature according to the claims can be mass-produced in a simple manner and inexpensively in a printing process that can be carried out with a printing press. In a defined, limited area, the identification feature contains a number of identification elements for identifying an object, one of which, however, is not recognizable in the visual range and therefore usually remains hidden from a human observer. A first identification element is designed as an arrangement of characters and/or carriers of meaning belonging to a code. In an advantageous embodiment variant, the first identification element is designed as an arrangement of characters or carriers of meaning of a multidimensional code, e.g. B. in the form of a QR code having a pixel pattern. A first identification element designed in this way can be both generated and machine-readable without a high outlay in terms of equipment. A conventional smartphone equipped with a camera and an app suitable for reading a QR code, i. H. Application software has. The second identification element is designed as a random structure formed from pigments or a dye, this random structure only being recognizable by irradiation with electromagnetic energy of a specific wavelength in the visual range and thus being photographically imageable. The random structure makes the identification feature unique, so that the second identification element can be used to check the authenticity and/or identity of the object bearing the relevant identification feature, e.g. B. is easily possible by a comparison with a previously created pattern image. The pigments or at least one dye of the second identification element are contained in a printing ink or in an ink, so that z. B. pixels of the first identification element formed from this printing ink or ink can be arranged on the object by means of a printing form-bound printing process or by means of a printing form-free printing process.

An exemplary embodiment of the invention is shown in the drawings and is described in more detail below on the basis of and taking into account the general explanations given above on scientific and/or technical matters.

• 1 ein Identifikationsmerkmal mit einem QR-Code;
• 2 eine Darstellung einer Zufallsstruktur innerhalb des QR-Codes.

Show it:

• 1 an identifier with a QR code;
• 2 a representation of a random structure within the QR code.

1 shows an example of an identification feature 01 with a plurality of identification elements for identifying and/or authenticating an object bearing this identification feature 01, with the identification feature 01 e.g. B. is arranged on a surface of this object. The identification elements of the identification feature 01 are located within a defined, limited area on or on the object. All identification elements belonging to the identification feature 01 in question are arranged within the area occupied by the identification feature 01 in question on the surface of the object in question. Thus, at least a first identification element and a second identification element are present in this same area. The first identification element is in the form of an arrangement of characters and/or carriers of meaning belonging to a code, each of the characters or carriers of meaning in this arrangement being in the form of a raster graphic consisting of pixels. The pigments or the particles of the at least one dye of the second identification element are contained in a printing color or in an ink, with the pixels of the first identification element being formed from this printing color or ink in question.

In a first advantageous embodiment variant, the first identification element is in the form of a multidimensional code, e.g. B. as a two-dimensional code having a pixel pattern, in particular as a QR code. In the case of the design as a pixel pattern, there are at least two contrasting configurations of pixels 02 in the pixel pattern in question, ie configurations that form an optical contrast relative to one another, ie at least two different types of pixels 02 are present. In the relevant first identification element, these pixels 02 are available in at least two different color tones, e.g. B. designed in a color pairing, z. B. in the pairing black / white or in the pairing blue / yellow or in the pairing red / green. Of course, other color pairings or the use of more than two color tones are also possible, as long as the color tones used have sufficient contrast for the visual perception carried out with an optical or visual system. The contrast can then be considered sufficient, when the different sorts of pixels 02 as such from the optical or visual system, e.g. B. from a data acquisition device or image recording device, in particular a scanner or a (semiconductor) camera, z. B. with a CCD image sensor or with a CMOS image sensor, reliably optically perceptible and the different configurations of the pixels 02 are clearly distinguishable from each other. This minimum contrast depends on the design of the optical or visual system used and also on the lighting conditions surrounding the relevant identification feature 01 at the time of data acquisition or image recording. The pixels 02 of the pixel pattern are preferably in the form of a rectangle, in particular a square, in their geometric configuration. An arrangement of the respective pixels 02 chosen to form the pixel pattern represents a z. B. with the help of a computing unit using mathematical algorithms encoded, in particular machine-readable information content 1 and 2 a link to the website www.kba.com is encoded in the QR code.

In a second advantageous embodiment variant, the first identification element is designed as visually readable or haptically detectable writing. In this case, the writing has in particular at least one alphanumeric character. In a further advantageous embodiment variant, at least one carrier of meaning belonging to the code in the arrangement is designed as a pictogram or as an ideogram.

In a first operating state of identification feature 01, the first identification element is visually recognizable by irradiating the surface containing the identification elements with visible light, and the second identification element is not visually recognizable. In a second operating state of identification feature 01, by irradiating the surface containing the identification elements with electromagnetic radiation that differs from the first operating state, the random structure formed from pigments or from particles of at least one dye of the second identification element, which is within the same defined, limited area as the first identification element is arranged on the object, visually recognizable. The random structure of the second identification element, formed either from pigments or particles of the at least one dye, preferably represents a second machine-readable information content. If the random structure of the second identification element, formed either from pigments or particles of the at least one dye, represents a second machine-readable information content, this information content is preferably a computing unit z. B. determined by a gray value determination or another threshold evaluation with regard to the number and / or the intensity of the pigments or particles in question. The respective information content of the first and/or second identification element can preferably be read omnidirectionally.

As the 2 shows by way of example, the second identification element is designed as a random structure formed from pigments 03 or the at least one dye, with the random structure of the second identification element formed from pigments 03 or the at least one dye only becoming visible as a result of exposure to electromagnetic energy, e.g. B. from the UV range triggered optical change for a viewer in the visual range is recognizable and photographically imageable. For the optical perception of the second identification element, an excitation is required, which takes place in the form of an energy supply, this energy being of an electromagnetic nature and preferably originating from a radiation whose respective wavelength is z. B. is in the UV range. In principle, an emission spectrum of the radiation that is radiated into the surface containing the identification elements in the second operating state of the identification feature includes the wavelength of at least one absorption line of the pigments or of the particles of the at least one dye of the second identification element, with the wavelength of the pigment or radiant energy absorbed by the subject particles of the dye causes the subject pigment or particles of the dye to emit electromagnetic radiation in the visible light spectrum. In a preferred embodiment, the radiant energy of the electromagnetic radiation radiated into the surface having the identification elements in the second operating state of the identification feature is at least 1.59 eV.

The pigments 03 or the particles of the at least one dye of the second identification element are contained in a printing ink or ink used for the printing production of the first identification element, i.e. here for printing the QR code, for example, with at least a subset of the pixels 02 of the first identification element forming Pixel pattern are formed from this ink or ink in question. The first identification element and the second identification element are each preferably in a printing form-bound printing process, z. B. in an offset printing process or in a gravure printing process or in a letterpress process, or in a printing formless, ie direct printing process, e.g. B. in an inkjet printing process or in an aerosol jet printing process, on the object, ie arranged on its surface or applied to the object. The object on the surface of which the identification feature 01 is formed is e.g. B. a printing material, on which several identification features 01 in a printing process z. B. be formed in a benefit. The printing material is z. B. formed as a material web or as a printed sheet, the printing material z. B. consists of paper or a plastic film or a metal foil. In another embodiment, the identification feature 01 is formed directly on the surface of the object by means of a printing process. B. as a packaging, in particular as a hollow body, z. B. as a (glass) bottle or as a (tin) can or as a plastic container, or as such a salable product z. B. is formed from a plastic or a ceramic or a metal or wood. If several identification features 01 are applied to the printing material, these are separated after they have been printed. The respective, e.g. Individual identification features 01, each configured as a label, are then available to be applied to another object or product whose identity and/or authenticity is to be checked at a later point in time using the relevant identification feature. The second identification element, which is embodied as a random structure formed from pigments 03 or the at least one dye, can, like the respective first identification element belonging to the same identification feature 01, be identical or different, i.e. individually embodied, for the multiple identification features 01 printed on the printing substrate in the same production process be.

In a preferred embodiment, the pigments 03 contained in the printing ink or ink and used to form the random structure have a core with a carrier substance and with either a fluorescent material or a phosphorescent material, with the core preferably being essentially spherical in shape. A shell surrounding the core is provided, the shell containing photochromic material with which a radiation emitted by the fluorescent material or the phosphorescent material is attenuated or at least can be attenuated. The pigments 03 used to form the random structure then correspond to e.g. B. the in WO 2007/005354 A2 described execution.

To identify the object bearing identification feature 01 and/or to check its authenticity, a method is proposed in which a first image of identification feature 01 is initially captured using a first contactless digital data capture device in a first lighting situation, with the captured first image being in the form digitized image data or first information decoded from the captured first image are each stored in a first memory. In a second lighting situation, different from the first, a second image of the same identification feature 01 is captured using a second contactless digital data capture device, with the captured second image in the form of digitized image data or second information decoded from the captured second image being stored in a second memory will. In the second lighting situation, a lighting device with at least one light source made of a semiconductor material or a lighting device with at least one gas discharge tube is used. The first non-contact digital data acquisition device and the second non-contact digital data acquisition device are z. B. in each case a scanner or as a camera, in particular as a digital camera. The first image is captured and/or the second image captured, e.g. B. using a trained as an application program code reader, z. B. a QR code reader or a program for automated text recognition or optical character recognition. The first memory and / or the second memory are z. B. in each case as a database, possibly also as the same database, in which the respective image is stored in digitized form in the form of digitized image data and/or information decoded from the relevant image in question is digitized.

The mapping and / or decoding takes place before the object z. B. is delivered to a user by a supplier, who can also be the manufacturer of the object in question, ie z. B. at a point in time during the manufacture of this object or when the identification feature 01 is applied to or on the object or product in question. At another, later point in time and usually elsewhere, the user uses the irradiation of electromagnetic energy z. B. from the UV range in the second identification element, the second image of the identification feature 01, wherein the image data from this second image and / or its decoded information is stored at least briefly. To identify the the identification object bearing feature 01 and/or to check the authenticity of this object, the image data of the stored first image of the identification feature 01 arranged on the object and the image data of the recorded second image of the identification feature 01 arranged on this object are then preferably processed in a computing unit, e.g. B. compared with image processing methods and checked for consistency. Alternatively or additionally, the first information item decoded from the captured first image and the second information item decoded from the captured second image are preferably compared with one another in the processing unit and checked for consistency.

If the stored first image of the identification feature 01 arranged on or on the object matches and/or does not match and/or does not match the stored first image of the identification feature 01 arranged on or on this object, the processing unit executing the comparison issues a message relating to the result of the comparison generated to the user and/or to the supplier or manufacturer of this item and/or e.g. B. output optically on a display device or acoustically. The comparison of the stored first image of the identification feature 01 arranged on the object with the recorded second image of the identification feature 01 arranged on this object, i. H. the previously described comparison of their respective digitally available image data or the respective decoded information in a mobile communication device, e.g. B. be executed in a smartphone, which nowadays usually each have a sufficiently powerful computing unit.

In another embodiment variant, the captured second image of the identification feature 01 arranged on or on the object in question is captured by the second data capture device, preferably via a wireless communication link, e.g. B. via the Internet or a cellular connection to a z. B. from the supplier or manufacturer of the item or operated for him stationary computer, z. B. transfer a network server. The transmission of the image data or the decoded information of the captured second image of the identification feature 01 arranged on or on this object to the stationary computer and/or a transmission of the message relating to the comparison result from the stationary computer to the user and/or to the supplier or manufacturer of the object in question and/or a transmission of the message relating to the comparison result from the user to the stationary computer and/or to the supplier or manufacturer of the object in question is preferably encrypted in each case.

In a particularly preferred embodiment of the invention, in an amount of z. B. identification features 01 printed in the same production process for all identification features 01 belonging to this set whose respective first identification elements are designed identically, i. H. they are all encoded with the same information, whereas the respective second identification element belonging to a specific identification feature 01 is designed differently from the other second identification elements belonging to this set. This means that in a certain, e.g. B. in the same production process, in particular with a printing press, these identification features 01 can only be distinguished from one another by their random structure, which is formed from pigments or the at least one dye, which forms the second identification element in each identification feature 01, but precisely because of this of this difference are also clearly identifiable. The random structure in question is e.g. B. by adding fluorescent pigments or other luminescent or at least reflective or polarizing particles to the printing ink or ink to be printed and a stochastic distribution of these pigments or particles in the printing ink or ink in question, the pigments or particles in question in relation to the area of the respective pixel z. B. the pixel pattern of the first identification element are each small. In an alternative embodiment, in an amount of z. B. identification features 01 printed in the same production process, not only the respective second identification elements, but also at least a subset of the respective first identification elements can each be configured individually, in that the relevant first identification elements or all first identification elements of this set of identification features 01 are in the relevant subset are encoded with information that differs from other identification features 01 of this set.

It can be provided that z. B. at the end of a production line for producing a certain amount of identification features 01 of these identification features 01 in the relevant, z. B. designed as a printing press production machine continuously according to the production progress for the production of this set of identification features 01 of each completed Identification feature 01 with a contactless digital data acquisition device, e.g. B. with a scanner or with a camera, at least one first image recorded and z. B. in the form of digital image data is stored in a first memory, in particular in a database, with this at least one first image of the relevant identification feature 01 in each case only depicting its first identification element or in each case its first identification element together with its second identification element. To carry out the mapping of the identification feature 01 in question in the relevant, e.g. B. designed as a printing machine production machine or processing machine is a lighting device with at least one light source made of a semiconductor material, z. B. an LED or laser lighting device, and / or a scanner or a semiconductor camera with a CCD image sensor or a CMOS image sensor used. Alternatively, a lighting device with at least one gas discharge tube can be used, e.g. B. with a xenon-filled flash tube. The production machine or processing machine can also be designed as a packaging machine or as a filling system or as a packaging machine. The first image is preferably captured without using a polarization filter or a color filter or another additional device manipulating the light reflected by the identification feature 01 in question.

This results in a method for identifying an object, in which an identification feature 01 with a plurality of identification elements is used to identify the object, with the identification elements being arranged within a defined, limited area on or on the object, with the identification feature in a first operating state 01 by irradiating the surface containing the identification elements with visible light, a first identification element becomes visually recognizable and a second identification element is not visually recognizable, the second identification element being designed as a random structure formed from pigments or as a random structure formed from particles of at least one dye or is, wherein in a second operating state of the identification feature 01 by irradiating the surface having the identification elements with one of the first operating state d different electromagnetic radiation, the random structure of the second identification element is visually recognizable, from the identification feature 01 with a first preferably contactless digital data acquisition device in a first, z. B. lighting situation using white light, a first image is captured, the captured first image in the form of digitized image data or first information decoded from the captured first image being stored in a first memory, wherein in a second, different from the first lighting situation of a second image is captured with the same identification feature 01 using a second, preferably non-contact, digital data capture device, with the captured second image in the form of digitized image data or second information decoded from the captured second image being stored in a second memory, with a lighting device being used in the second lighting situation with at least one light source made of a semiconductor material or an illumination device with at least one gas discharge tube is used. The first memory and the second memory are each z. B. formed as a database. In the second lighting situation, electromagnetic radiation is used, which is at least partially absorbed by the pigments or the at least one dye of the random structure. The electromagnetic radiation-absorbing pigments or the at least one electromagnetic radiation-absorbing dye of the random structure are excited to luminescence by the at least partial absorption of the electromagnetic radiation in question, with the second image being recorded by the second data acquisition device during the luminescence of the pigments or the at least one dye of the random structure is detected.

Reference List

01

identifier

02

pixel

03

pigment

Claims (14)

Identification feature (01) with a plurality of identification elements arranged in a defined, limited area for identifying an object, wherein in a first operating state of the identification feature (01) by irradiating the area containing the identification elements with visible light, a first identification element is visually recognizable and a second identification element is visually recognizable is not recognizable, the second identification element being formed as one of pigments (03). dete random structure is formed, wherein in a second operating state of the identification feature (01) by irradiating the surface containing the identification elements with electromagnetic radiation that differs from the first operating state, at least the random structure of the second identification element is visually recognizable, with the first identification element being an arrangement of to characters and/or carriers of meaning belonging to a code, the pigments (03) of the second identification element being contained in a printing ink or in an ink, the random structure of the second identification element being a representation of second machine-readable information, characterized in that each of the Characters or carriers of meaning of the arrangement of the first identification element are each designed as a raster graphic consisting of pixels (02), the pixels (02) of the first identification element from which the P pigments (03) of the second identification element are formed, wherein the pigments (03) of the second identification element have a core with a carrier substance and either with a fluorescent material or with a phosphorescent material, with a shell surrounding the core being provided, wherein the shell contains photochromic material with which radiation emitted by the fluorescent material or the phosphorescent material can be attenuated, wherein the pixels (02) containing the pigments (03) of the second identification element are printed on or in an offset printing process or in an inkjet printing process are arranged on the object. Identification feature (01) after claim 1 , characterized in that the first identification element is designed as an arrangement of characters or carriers of meaning of a multidimensional code. Identification feature (01) after claim 2 , characterized in that the arrangement of the multidimensional code has a pixel pattern with at least two types of pixels (02), these types of pixels (02) each having a contrast relative to one another, with at least one of the types of pixels (02 ) is formed from the printing ink or ink containing the pigments (03). Identification feature (01) after claim 1 or 2 , characterized in that the arrangement of the pixels (02) is a representation of a first machine-readable information encoded with a mathematical algorithm. Identification feature (01) after claim 3 , characterized in that the arrangement of the pixels (02) is a representation of a first machine-readable information encoded with a mathematical algorithm. Identification feature (01) after claim 1 or 2 , characterized in that the first identification element is designed as a QR code. Identification feature (01) after claim 3 or 5 , characterized in that the first identification element is designed as a QR code. Identification feature (01) after claim 3 or 5 or 7 , characterized in that the different types of pixels (02) are formed in at least two different shades. Identification feature (01) after claim 1 , characterized in that the first identification element is designed as a visually readable or haptically detectable writing. Identification feature (01) after claim 9 , characterized in that the font has at least one alphanumeric character. Identification feature (01) after claim 1 , characterized in that at least one signifier belonging to the code in the arrangement is designed as a pictogram or as an ideogram. Identification feature (01) after claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8th or 9 or 10 or 11 , characterized in that an emission spectrum of the radiation that is radiated into the surface having the identification elements in the second operating state of the identification feature (01) includes the wavelength of at least one absorption line of the pigments (03) of the second identification element, the wavelength of the relevant Pigment (03) absorbed radiant energy causes the pigment (03) in question to emit electromagnetic radiation in the spectrum of visible light. Identification feature (01) after claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8th or 9 or 10 or 11 or 12 , characterized in that the radiation energy of the electromagnetic radiation radiated into the surface having the identification elements in the second operating state of the identification feature (01) is at least 1.59 eV. Identification feature (01) after claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8th or 9 or 10 or 11 or 12 or 13 , characterized in that the respective information of the first and / or second identification element is omnidirectional readable.

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