RU2499674C1 - Data carrier having window - Google Patents

Abstract

FIELD: physics, computer engineering.

SUBSTANCE: invention relates to a data carrier, in particular a valuable or security document. The data carrier has window which extends from a lower side to an upper side of the data carrier, and a film element having a security element which covers the window on the upper side of the data carrier. One portion of the security element lies over the window and one portion of the security element lies adjacent to the window. The portion of the security element lying over the window has a radiation-modified region which is superimposed with the window, wherein the visual appearance of the security element is modified by means of electromagnetic radiation on said portion.

EFFECT: data carrier provides high counterfeit protection.

29 cl, 22 dwg

Description

The invention relates to a data carrier, in particular a valuable or security document, comprising a window extending from the lower side to the upper side of the data carrier, and a film element with a protective element that covers the window from the upper side of the data carrier, and a part of the security element is located above the window, and part of the security element is next to the window.

Protected or valuable documents, such as banknotes, certificates and similar documents, are often provided with security features. These elements allow you to verify the authenticity of documents and at the same time serve as protection against illegal reproduction. Moreover, more and more attention is paid to transparent security features, for example, transparent windows in banknotes. For the manufacture of a window, for example, a film is applied to a banknote, provided with an adhesive layer on one side to close a through hole previously made in the banknote.

The application of a film to a banknote is associated with the inevitable presence of tolerances for alignment, so the security element on the film, specially adapted to the hole, cannot be perfectly aligned with the hole. Such combination tolerances must be taken into account when creating the design of the security element, which limits freedom in making design decisions.

Based on the foregoing, the objective of the present invention is to improve the data carrier of the above type and, in particular, to provide overhead protective elements having patterns precisely aligned with the window, which, in turn, allows you to combine an attractive appearance with a high degree of protection.

This problem is solved thanks to the data carrier, characterized by the features of the main independent claim. A method of manufacturing such a storage medium is disclosed in another independent clause. Options for further development of the invention are the subject of dependent clauses.

In accordance with the invention, the data carrier of the type in question provides that the part of the protective element that is located above the window has a section that is modified by radiation, this section is aligned with the window, and the appearance of the protective element in this section is modified as a result of electromagnetic radiation .

The invention is based on the following idea: the presence of tolerances for the combination between the protective element of the applied film element and the window of the data carrier is acceptable, but at the same time, through the action of radiation, in particular by laser exposure, the appearance of the protective element in the modified section aligned with the window is changed. Deviations in the alignment between the film element and the window during observation to a large extent or completely fade into the background, and the greatest influence on the visual perception of the observer is the exact alignment between the window and the modified area.

Due to the exact alignment of the window and the modifiable area with respect to each other, these two elements can be coordinated or correlated with each other also in terms of their appearance and / or their information content. For example, a window and a section to be modified may represent the same pattern, or each of these elements may represent only part of a pattern, and these parts complement each other to a common pattern. Such a visual or substantive relationship, on the one hand, attracts the attention of the observer and is well remembered, and on the other hand, leads to an increase in the degree of protection against counterfeiting, since the production of security signs - a window and modifiable areas that are meaningfully connected with each other, more technologically difficult than to make two separate security signs or security signs that are not related to each other in content.

The data carrier window may be formed by a through hole extending from the lower side to the upper side of the data carrier. The window can also be formed by a transparent portion of the data carrier, which allows observation in transmitted light, for example, the unsealed area of the polymer banknote. In multilayer media, a window can also be formed due to a combination of transparent areas in the first layers of the medium and through holes in the second layers of the medium, such as paper layers, and a partially transparent layer of a multilayer banknote susceptible to printing ink.

In a preferred embodiment of the invention, the protective element has a metal layer demetallized in the area modified by radiation. In this case, demetallization refers to the removal of a metal layer or its transformation into a transparent layer. The metal layer can be completely demetallized, that is, completely removed or completely transformed into a transparent layer, or demetallized only partially to create a still translucent modifiable area, in particular with a light transmission of 20 to 80%. As explained in more detail below, in the area of the hole, the metal coating can only be demetallized in separate sections, so that the section modified by radiation within the hole creates a substructure exactly aligned with the hole.

The security element, in particular, comprises a metallized diffraction structure, a metallized reflective diffraction structure, a metallized opaque structure or a thin film element with a color-changing effect, which is usually formed from a metal reflective layer, a dielectric separation layer and an absorbing layer. In addition, other protective elements with metallized structures, for example metallized concave micro-reflectors, can also be taken into account.

In a preferred embodiment of the invention, the protective element has first and second sub-sections that interact with electromagnetic radiation in different ways, both the first and second sub-sections being partially located above the window and partially next to the window. Moreover, different interactions may consist in different intensities of this interaction or its different type.

For example, different intensities of interaction in the case of metallized protective elements can lead to demetallization of only the first subsection, and in the case of protective elements that can be painted or discolored by radiation, to a color change of only the first subsection or also to a strong color change of the first subsection. When interacting with different intensities, both subsections react, in the same way, in the same way, but one subsection is stronger than the other, which reacts weaker or does not even react at all.

On the contrary, in the interaction of different types, both subareas react to radiation exposure, but in a different way. For example, a colorless portion of a protective element stained by radiation can be colored red on the first subsection and blue on the second subsection. In addition, in this way, a different appearance can be achieved on the site to be modified.

In a preferred embodiment of the invention, the radiation-modified portion contains only the first sub-sections and does not contain second sub-sections, so that the second sub-sections located above the window and near the window have the same appearance.

In order to achieve different interaction intensities, in one of the preferred embodiments of the invention, at least one of the two sub-regions has an interference structure, preferably a relief structure in the form of a lattice, which is determined by the lattice constant and the orientation of the lattice strokes. The second subsection may not contain a relief structure or may also contain a relief structure in the form of a lattice, which is defined by the second lattice constant and the second orientation of the lattice strokes, the second lattice constant and / or the second orientation of the lattice strokes of the second subsection is different from the first lattice constant and, accordingly, the orientation strokes of the lattice of the first subsection. The lattice of the second subsection can also have the same lattice constant and the orientation of the strokes of the lattice as the lattice of the first subsection, but it can be tilted at some angle relative to the first lattice, for example, due to the fact that the lattice is located on the lateral surfaces of the sawtooth structure.

Material removal is carried out using a lattice exhibiting increased absorption. From the point of view of physics, increased absorption of light can be explained by resonant excitation in a metal (resonance of surface plasmon polaritons or resonance in a hollow resonator). For this, the lattice constant is expediently chosen so that its order corresponds to the wavelength of the laser radiation used to modify the radiation. In addition, the resonant absorption of light in the grating strongly depends on the cross section of the profile and the material of the grating, as well as on the surrounding material. Further, in order to achieve high absorption, the profile is expediently consistent with the wavelength of the applied laser radiation. For example, a grating having laterally grooves of different depths exhibits various absorbing properties in the lateral direction. In a preferred embodiment, the first sub-section contains a grating with the highest possible absorption, and the second sub-section is made without a grating. In this case, with an appropriately selected wavelength, angle of incidence, and polarization, the incident laser radiation leads to demetallization of the grating region.

In particular, the second orientation of the grating strokes can be arranged substantially perpendicular to the first orientation in order to achieve different interaction of the sub-regions with linearly polarized electromagnetic radiation. In a preferred embodiment, both sub-regions comprise a grating with a grating constant of 750 to 1050 nm, preferably approximately 900 nm, and with different orientation of the grating strokes.

Another option that allows you to create a different interaction for two sub-sections filled with lattices is to use lattices with different lattice profiles for the first and second sub-sections. Particularly preferred are embodiments of the invention in which both subsections interact with polarized laser radiation to varying degrees, since a noticeable difference in the intensity of interaction can be achieved in a simple way. In an improved embodiment, it is envisaged that both subareas are formed from subzones embedded in each other. In particular, the subzones may consist of parallel strips, preferably between 10 and 500 microns wide.

In yet another embodiment of the invention with differently interacting sub-regions, the first sub-region comprises a surface area-increasing relief structure, preferably a surface-area-increasing relief structure with a cross sinusoidal surface microrelief. The surface microrelief, for example, may have a height of 200 to 400 nm, preferably approximately 300 nm, and an x and y axis lattice constant of 200 to 400 nm, preferably approximately 300 nm.

Additional information regarding the selective removal by radiation of only one of two or more subareas is given in WO 2006/079489 A1, to which extent the description contained in this document is included in this description.

In yet another embodiment of the manufacture of differently interacting sub-regions, the first and second sub-regions are formed by bulges and indentations made by embossing. For this, in particular:

- the substrate is provided with a relief structure with bulges and recesses, create the first and second sections with different first and second level heights, and the second sections of the relief structure are made in the form of the desired pattern;

- a relief structure with first and second sections metallize over the entire surface;

the metallized embossed surface is treated with radiation to selectively remove the metal coating in the second portions of the embossed structure as a result of the action of the radiation.

The radiation treatment can be carried out, in particular, using laser radiation.

In this case, preferably after the metallization operation, a coating layer that absorbs and / or reflects laser radiation is applied to the metallized relief structure, which fills the recesses of the relief structure. When choosing a coating layer, it is important that less intense laser radiation passes through the recess area. Therefore, the coating layer reflecting the laser radiation can exhibit the same or even better effect than the coating layer absorbing the laser radiation. After application, the coating layer from the convex parts of the metallized relief structure is removed, in particular, removed with a doctor blade or washed. In this case, on the convex parts of the metallized relief structure, a thin tinting film of the coating layer that is inevitable from a technical point of view may remain. Such a coating layer preferably contains absorbing or reflecting laser radiation pigments or dyes, in which case it can additionally be used as a paint layer in order to design a design that is visually distinguishable from the bottom. Other details and structuring options based on a metallized relief structure with bulges and recesses are described in patent application PCT / EP2009 / 00882, to which extent the description contained in this document is included in this description.

The present invention can be applied in micro-optical structures for displaying images, for example, in micro-optical moire magnifying structures, micro-optical magnifying structures of the moire type and more general magnifying structures based on modulo calculations, which are, in particular, described in international applications WO 2009/00528 A1 and WO 2006/087138 A1, the description of which is included to this extent in this application. All of these micro-optical magnifying structures contain an image of a pattern with microstructures that, when observed using an appropriately matched observation grid, reproduces a given image.

As explained in more detail in the aforementioned publications and applications, in this case, they can create many attractive effects of magnification and movement, which are well remembered by the observer and increase the protection against counterfeiting of manufactured security elements. For example, the lattice parameters of the image of the pattern and the lattice for observation can be matched with each other so that when the structure for display is tilted, an orthoparalactic motion effect is obtained, in which the first pattern does not move parallel to the direction of the tilt, as they intuitively expect, but perpendicular to it.

In one embodiment of the invention, it is provided that the security element comprises microstructures with a stroke thickness of from about 1 μm to about 10 μm, the appearance of which in the area modified by the radiation is changed. These microstructures preferably form, at least inside or at least outside the area, a radiation-modified image of the pattern, divided into many cells, in each of which there are sections of a given image. Moreover, the dimensions of the image sections in the lateral direction are preferably from about 5 μm to about 50 μm, in particular from about 10 μm to about 35 μm. In addition, a viewing grating is preferably provided, consisting of a plurality of grating elements for reconstructing a predetermined image when observing a pattern image using a viewing grating, and in the lateral direction, the dimensions of the viewing grating elements are also preferably from about 5 μm to about 50 μm, in particular from about 10 microns to about 35 microns.

Modification in the area modified by radiation may, for example, consist in the selective removal of the metal coating, as a result of the microstructure of the image of the pattern become distinguishable. In another embodiment, the microstructures are colored, and in the area modified by radiation, the color of the microstructures is changed. Moreover, as a result of the action of radiation, in particular, the first paint can be converted into a second paint. In addition, one of these two colors can be transparent, in particular, the first paint can be discolored by the action of radiation and, thus, made transparent, or, as a result of the action of radiation, they can stain the transparent areas and, thus, make them colored.

In preferred embodiments of the invention, the microstructures inside and outside the area modified by radiation, in each case represent different patterns, in particular different patterns, characters or codes. In this case, when precisely aligned with the edges of the window, various patterns, characters or codes are changed.

For this, the microstructures are preferably arranged in a two-layer varnishing system containing two layers of varnish arranged one above the other and having substantially the same refractive index. In this case, the second image pattern is embossed in the lower varnish layer, and the first image pattern is in the upper varnish layer located above the lower varnish layer. In the area modified by radiation, the top layer of varnish is removed, so that the second pattern of the bottom layer of varnish in this section and the first pattern of the top layer of varnish outside the section can be visually recognized.

In yet another embodiment of the invention, it is provided that the security element comprises a plurality of reflective first elements for displaying micro images located over the area in the structure of the elements for observation and passing second elements for displaying micro images over the area in the pattern of the elements for observation;

moreover, the second elements for displaying the microimage are located inside, and the first elements for displaying the microimage are outside the area modified by radiation;

moreover, the protective element, in addition, contains a microstructural object containing several microstructures that are located in the microcircuit, consistent with the pattern of elements for observation so that the microstructural object with the first elements for displaying the microimage is displayed in enlarged view in front of the upper side;

moreover, with the second elements for displaying the microimage, an area of the object plane is located outside the protective element, so that the microstructures of the microstructural object are not perceived from the bottom side when observed by the second elements for reproducing the microimage, but for verification in the zone of the object plane, an additional microstructural object containing several microstructures, so that by means of the second elements of the microimage additional microstructural ekt displayed in enlarged form in front of the bottom side.

In this case, the first elements for displaying the microimage are made, in particular, in the form of concave micro-reflectors, and / or the second elements for displaying the microimage are made in the form of microlenses. Other details and advantages of such a combination of microlenses and concave microreflectors can be found in German patent application DE 102009022612.5, to which extent the description contained in this document is included in this description.

In accordance with the invention, no restrictions are imposed on the shape of the window. In all embodiments of the invention, the window may be made in particular in the form of a pattern, characters or codes. If the window is formed by a through hole, or the window contains a through hole, raster openings described in German patent application DE 102009011424.6, the disclosure of which is included in this application to this extent, can also be very preferably used. If the through hole is formed by such a linear lattice, consisting of many parallel cut lines, then due to the large number of transitions from the carrier to the hole, the above-described combination effects are even more pronounced.

In this description, in most cases we are talking about one through hole, even if, as follows from the examples, this hole consists of several parts, and it could be designated as a group consisting of several holes.

Alternatively or in addition to the window, the area modified by radiation may preferably be made in the form of a pattern, characters or codes. The patterns, signs or codes of the area modified by radiation and the window are very preferably the same or correlated with each other, for example complement each other to a common pattern.

In a preferred improved embodiment of the invention, it is provided that a film element with a laser-removable adhesive layer is deposited on the upper side of the data carrier, and the laser-removable adhesive layer is removed in the window region. As a result, a particularly distinct image of the appearance can be achieved in the window.

The invention also relates to a method for manufacturing a data carrier, comprising the following steps:

a) take the substrate of the data medium having a window extending from the lower side to the upper side of the medium, and a film element with a protective element;

b) cover the window on the upper side of the substrate of the data carrier with a film element so that part of the security element is located above the window and part of the security element is next to the window;

c) act on the protective element by electromagnetic radiation from the bottom side of the substrate of the data carrier and through the window to modify the appearance of the protective element in the section modified above the window by radiation.

In this case, in step c), the protective element is preferably subjected to laser radiation, in particular ultraviolet radiation, radiation in the visible region of the spectrum or radiation in the near infrared region of the spectrum with a wavelength of up to 1.5 μm.

In step b), the film element is applied to the upper side of the data carrier, preferably by means of a laser-removable adhesive, and the glue in the window area is removed in step c) by exposing it to a laser beam.

If the window is formed by a through hole or the window contains a through hole, then, in step a), the through hole is formed in a data carrier substrate or a data carrier layer containing a through hole, preferably by cutting or laser cutting using a cutting laser, preferably with a wavelength of about 10, 6 microns.

In addition, in the manufacture of the through hole, the portion adjacent to the hole on the underside of the substrate or layer of the data carrier may be colored or modified so that, due to the combination effects, integrate the hole on both sides of the substrate or layer of the data carrier. For this, it is preferable:

the substrate or layer of the data carrier, at least in the immediate vicinity of the through hole to be created, is provided with a laser-modifiable indicator substance;

a through hole is provided in the substrate of the data carrier or in the layer of the data carrier by means of laser radiation;

the laser-modifiable substance is modified near the hole by laser radiation.

In this case, the indicator substance can be modified not only in the area directly adjacent to the hole, between the laser-modified area and the hole there may be a certain small gap. When creating a through hole, the laser-modifiable indicator substance is preferably modified using the beam of the cutting laser itself. The fact that the energy of the laser radiation in the outer part of the beam profile of the cutting laser is sufficient is used to simultaneously modify the indicator substance in the immediate vicinity of the cut hole. In this way, the exact alignment of the holes and the laser-modified contiguous portion is automatically ensured.

Alternatively or additionally, during one operation, a through hole is created using a laser module, on the one hand, with a higher laser radiation energy, and an indicator substance is modified in the immediate vicinity of the hole with a lower laser radiation energy. Since both operations are carried out during one technological operation, they achieve precise alignment (the deviation is less than 0.4 mm, in particular less than 0.2 mm or even 0.1 mm) of the hole and the near-laser-modified region.

Other details and advantages of the method under consideration can be found in WO 2009/003587 A1, to which extent the description contained in this document is included in this description.

In the case of a data carrier, in particular, it can be a valuable document, for example a banknote, in particular a paper banknote, a polymer banknote or a banknote with a multilayer film, or an identity card, for example, a credit card, bank card, cash card, pass, identification card or passport page with personalizing data.

Other embodiments of the invention and its advantages are described below with reference to the drawings. For clarity, the scale and proportions in the drawings are not respected.

The invention is not limited to the specific examples of embodiments described below, but it is also possible to combine various options with each other.

The drawings show the following.

Figure 1 schematically shows a banknote in accordance with one embodiment of the invention.

Figure 2 shows the cross section of the banknote of figure 1 along the line II-II.

Figure 3 (a) -3 (c) shows a sequence of manufacturing steps and an example of a visual and meaningful relationship between the hole and the hologram.

Figure 4 (a) shows a cross section of the proposed security paper; figure 4 (b) and figure 4 (c) is a top view of the upper and, accordingly, the lower side of the security paper in the area of the hologram or through hole.

Figure 5 shows the intermediate stages of manufacturing the proposed security paper: Figure 5 (a) is a top view of the applied security element; 5 (b) is a plan view of a security paper before applying a security element; 5 (c) and 5 (d) - finished security paper in a plan view and, respectively, in cross section.

6 (a) and 6 (b) show intermediate steps in the manufacture of yet another proposed security paper.

7 shows a top view of a security paper made in accordance with one embodiment of the invention.

On Fig shows a view on the lower side of a security paper made in accordance with another embodiment of the invention.

Figure 9 shows a cross section of a micro-optical structure for displaying images made in accordance with one example embodiment of the invention.

Figure 10 shows a moire magnifying structure containing elements of the micro-cushion, causing a different color impression inside and outside the hole.

In Fig.11 shows the proposed micro-optical structure for displaying images, in which at the edges of the through hole there is a change in the displayed image of the pattern: Fig.11 (a) is in cross section, Fig. (B) is a top view.

On Fig, 13 shows two embodiments of the invention, created on the basis of a combination of microlenses and concave microreflectors.

The invention is illustrated by the example of banknotes. To this end, in Figs. 1 and 2, a banknote 10 is schematically shown in a top view and, respectively, in cross section, in paper 12 of which there is a window in the form of a through hole 14 extending from the lower side 16 to the upper side 18 of the paper 12. On the upper side 18 of the paper 12, the through hole 14 is covered with a strip of film 20.

Although the invention is illustrated below by way of example, according to which through holes are made in a banknote, it is not limited to this embodiment. Moreover, the data carrier window can also be formed by a transparent portion of the data carrier that allows observation through it, for example, by a transparent polymer banknote window. In multilayer media, a window can also be formed by a combination of transparent portions in the first layers of the medium and through holes in the second layers of the medium, for example paper, and a partially transparent layer of a multilayer banknote susceptible to printing ink.

The strip 20 of the film (as shown in figures 1 and 2) contains a protective element in the form of a metallized hologram 22, which is partially located above the through hole 14, partially next to it. For this, the hologram 22 usually has a larger area than the through hole 14, and the strip of film 20 is applied to the paper 12 of the banknote so that the hologram 22 completely covers the hole 14, and also covers the area adjacent to the hole 14, as shown in figures 1 and 2 .

In this embodiment, the part of the hologram 22 located above the through hole 14 forms a laser-modified portion 24, on which the appearance of the hologram 22 is changed due to laser radiation, and which in accordance with the invention is precisely aligned with the through hole 14.

This makes it possible, without deviations in alignment, to align the pattern 22, 24 represented by the hologram with the shape or shape of the through hole 14 and, thus, create a visual or meaningful relationship between the hole 14 and the hologram pattern 22, 24, as shown below with reference to specific embodiments of the invention . As a result, firstly, the hologram 22, 24 attracts the attention of the observer more and is better remembered by him, secondly, the protection against counterfeiting is increased, since the exact alignment of both elements - hole 14 and laser-modified section 24 - for a potential counterfeiter is difficult to overcome barrier.

The sequence of manufacturing steps and the first example of the visual and meaningful relationship between the hole and the hologram are illustrated in the plan views shown in FIG. 3.

As shown in FIG. 3 (a), in the manufacture of the security paper according to the invention, the film strip 30 is first provided with a metallized hologram, for example a hologram 32 in natural colors, which, for example, contains a pattern with a mountain chain 34 and sky 36, shown only schematically in the drawing. Then, through laser cutting in a paper 40, banknotes create a multi-part through hole 42, which, as shown in FIG. 3 (b), is a pattern in the form of a sun with concentric rays. Patterns of simpler shapes in paper can also be created with high quality not by laser cutting, but by cutting.

After that, the film element 30 with the hologram 32 is applied to the upper side 47 of the security paper 40 so that the hole 42 is in the sky 36 of the hologram 32. Then, from the bottom side of the security paper 40, the film element 30 is exposed to the laser element, for example, pulsed radiation, through the hole 42 Nd: YAG laser with a wavelength of 1.064 μm, as a result of which the metal coating of the hologram 32 is removed in areas that are located above the hole 42.

After that, the demetallized parts of the hologram form a laser-modified portion 38, in which the appearance of the hologram 32 is changed, as shown in Fig. 3 (c). Since the hole 42 serves as the mask for demetallization of the hologram 32, the laser-modified portion 38 is perfectly aligned with the edges of the hole 42.

The alignment tolerances that are unavoidable when applying the film element 30 to the security paper 40 are invisible to the observer in that part of the hologram pattern 32 that represents the sky 36, but they do not affect the alignment tolerances between the hole 42 and the laser-modified portion 38. Thus thus, the laser-modified portion 38 and the hole 42 may be consistent with each other in the design of the pattern without regard to alignment tolerances. For example, in the embodiment shown in FIG. 3, the laser-modified portion 38 is aligned visually and meaningfully with the hole 42 due to the fact that both of these regions represent the same pattern without offset (sun with rays). Of course, as described in more detail below, more complex relationships can be created within the framework of the invention.

According to an embodiment of the invention, the areas that will be located around the proposed laser-modified section 38 can be provided with pigments or substances with special features in order to change the appearance of the section 38, if desired. For example, the section adjacent to the expected laser-modified section 38 of the hologram 22, can provide a layer with variable optical properties, for example a liquid crystal layer with a color-changing effect. In this case, after applying to the security paper and demetallizing in the area 38, when viewing in transmitted light, a light hole 42 is seen, while when the security paper 40 is applied to a dark background, the effect of changing the optical properties of the liquid crystal layer is noticeable. In this case, the desired color impression of the liquid crystal layer can be controlled, for example, by choosing a liquid crystal substance and a layer thickness with variable optical properties.

Figure 4 illustrates another example embodiment of the invention shown in figure 3, in which, thanks to the combination effects, the through hole 42 is integrated not only on one but also on both sides of the security paper 40. In this case, figure 4 (a) shows the cross section of the security paper, and Fig. (b) and Fig. 4 (c) show a top view of the upper and, respectively, lower side of the security paper 40 in the hologram or through hole area.

To achieve the effect of combining security paper on both sides, before cutting through hole 42 in the area 44 adjacent to the hole being created, security paper 40 was provided with a laser-modifiable indicator substance, which under the influence of radiation from a CO ₂ laser with a wavelength of 10.6 μm changes color, for example, from transparent to red, but does not modify under the influence of laser radiation with a wavelength of 1.064 μm or 532 nm.

If after that, with the help of a cutting CO ₂ laser, an opening 42 is cut out from the bottom side 46 of the security paper 40, then due to the Gaussian profile of the laser beam in the portion 48 adjacent to the opening 42, the threshold energy necessary to turn the color of the indicator substance from transparent to red, still exceeded. As a result, the hole 42 made on the lower side 46 of the paper 40 has a red edge 48 surrounding it.

To complement the design 50 of the underside 46, the security paper 40 can optionally be further processed by radiation of a CO ₂ laser with lower energy, at which only the color conversion threshold is exceeded, but not the energy threshold necessary for cutting, so that additional colored areas appear on the underside 52. Since the cutting of the hole 42, the coloring of the adjacent sections 48 and the coloring of the uncut sections 52 are carried out using the same beam of the cutting laser during the same technological process operation, the painted areas 48, 52 and the hole 42, as shown in figure 4 (c), are perfectly aligned with each other. Additional information regarding laser-modifiable indicator substances that can be used in this improved embodiment and additional coloring options for areas adjacent to the through hole can be found in WO 2009/003587 A1, the contents of which are incorporated herein by reference.

After applying the film element 30 (see Fig. 3 (a)) to the security paper 40 (see Fig. 4 (a)) and demetallizing the hologram in the laser-modified section 38 on the upper side of the paper 40, the one shown in Fig. 4 (b ) a pattern corresponding to the pattern shown in FIG. 3 (c). Figure 50 of the bottom side 46 does not change during demetallization, since the indicator substance of sections 44 does not react to the radiation of the Nd: YAG laser used for demetallization, i.e., the energy, more precisely, the radiation density (the amount of energy per unit area) is insufficient for the corresponding reaction . The latter occurs in particular if a thermosetting pigment is used.

In general, the finished security paper looks like that shown in Figs. 4 (b) and 4 (c), respectively, above and below, and due to the combination effects, the hole 42 on both sides is integrated into the overall image (landscape with the sun and, accordingly, the wheel with knitting needles).

The portion of the security element modified by radiation in accordance with the above-described embodiments of the invention may cover the entire area of the through hole. However, a section modified by radiation can occupy only a part of the area of the through hole and, thus, form a substructure within the area of the through hole. To create such a section, modified under the influence of radiation, precisely aligned with the hole and provided with a substructure, the following approach can be applied.

In the example shown in FIG. 5, first, the film element 60 is provided with a protective element 62 having first and second sub-sections 64 and, respectively, 66, which to varying degrees interact with the electromagnetic radiation used for modification. For this, the subareas 64, 66, for example, can be filled with metallized gratings, the strokes of which are rotated 90 ° relative to each other, as shown schematically in Fig. 5 (a) by different hatching of the subareas 64, 66. The shape of the subareas 64, 66 forms the desired pattern, for example, shown in figure 5 (a) the sequence of letters "PL".

Then, the film element 60 is applied to the security paper 70 having a through hole 72 (FIG. 5 (b)) and is exposed to it from the bottom side of the paper 70 through the through hole 72 by a linearly polarized electromagnetic radiation of an Nd: YAG laser.

With the corresponding orientation of the plane of polarization of the laser radiation, this radiation is absorbed by sub-regions 64 significantly more than sub-regions 66, so that the energy or intensity of the laser radiation is sufficient to demetallize the sub-regions 64, while it does not demetallize in the sub-regions 66 with weaker absorption. Thus, only subareas 64 are selectively demetallized in the region of the opening 72.

Since the through hole 72 serves as a mask for metallization in some areas, the laser-modified section 74 of the protective element 62 is precisely aligned with the edges of the hole 72. The sections 66 not demetallized by laser radiation continue without any displacement from the section outside the hole 72 by a portion of the hole 72, as shown in a plan view (FIG. 5 (c)) and in cross section (FIG. 5 (d)).

In preferred embodiments, using the lattices made in the lateral direction in different ways, different interactions of the sub-regions 64, 66 can be achieved, with one sub-region having a high absorption capacity and the other sub-section that should not be demetallized, has a low absorption capacity. This corresponds to the configuration shown in FIG. Especially great contrast with respect to absorption between these sub-regions is achieved if surface plasmon polaritons are excited in one region with the lattice, and the other sub-region does not allow such resonance excitation. A predominantly linearly polarized laser radiation with a certain wavelength and a certain angle of incidence is suitable as a radiation source. Surface plasmon polaritons can lead to complete absorption of incident TM polarized light (the vector of the electric field is directed perpendicular to the bars of the grating). On the contrary, in the case of metal gratings with high conductivity, TE-polarized light (the electric field vector is directed parallel to the grating lines) is almost not absorbed. Due to this, with the help of gratings containing differently oriented sub-sections (the difference is 90 °), the absorption ratio can reach a contrast of more than 10, and in the infrared range even more than 100 times. Noble metals Au, Ag, Pt, as well as Al, Cr and Ni, are particularly suitable for metallization.

For example, in the case of a reflective grating with a rectangular groove profile, the grating period is 1 μm and the groove depth is 0.6 μm, with an incident radiation wavelength of 1064 nm, an incidence angle of 1 °, and TM polarization for Au, Al, Ag, and Cu metals we obtain pronounced absorption maxima depending on the depth of the groove, which in the case of Ag and Cu and at a groove depth of approximately 110 nm almost reach a maximum absorption of 100%.

Since the position of surface plasmon polaritons in the wave spectrum depends not only on the lattice period, but also on its profile and optical constants, differences in absorption can also be achieved in subareas in which these lattice parameters change. In addition, high absorption of TE-polarized light and lower absorption of TM-polarized light can be achieved using the corresponding structure of the grating profile. Moreover, such absorption of TE-polarized light is based on the resonance effect, which is especially pronounced in the case of deep lattice structures (the depth of the groove is more than half the period).

Different interactions of the subareas 64, 66 can be achieved in another way, for example, due to different relief structures increasing the surface area. In this case, selectivity is based on the fact that when a metal layer is sprayed onto relief structures of different "roughness", the rougher the relief, the thinner the metal coating. In addition, with coarser structuring, incident laser radiation is generally reflected more often, and therefore it gives more energy to the metal coating, so that in general coarser embossed structures can demetallize using even a small amount of laser radiation energy. In this case, the ratio of depth to width is decisive. The larger this ratio, the better results can be achieved by demetallization.

Therefore, in order to enable selective demetallization of the subareas 64, the subareas 64, 66 can also be performed with a coarse relief structure (subarea 64) and a fine relief structure (subarea 66). Additional information regarding the selective removal of only one of two or more subareas is described in WO 2006/079489 A1, the contents of which are incorporated herein by reference.

Another possibility, to create sub-sections in the protective element with different interaction intensities, is based on the use of a metallized relief structure with purposefully created bulges and indentations. Figure 6 shows an example embodiment of the invention in which the film element 90 is applied to the security paper 80 with a through hole 82 using hot melt adhesive 84. The film element 90 comprises a film substrate 92, which is provided on one side with a UV curable embossing varnish layer 94 .

A relief structure with bulges 96 and recesses 98 is embossed in the embossing varnish layer 94. Here, the terms “bulge” and “recess” refer to the surface of the film substrate 92, so that those elements that are directed downward in FIG. 6 (a) are bulges, which, when viewed in the direction from the surface of the film substrate 92, rise above the recesses 98.

In this embodiment, the bulges 96 also have a microrelief structure in the form of a desired hologram. The entire relief structure with bulges 96 and recesses 98 is provided with a metal coating 100, for example, of aluminum, which also forms a hologram metal coating for the microrelief structure of the bulges 96.

In addition, the metallized relief structure over the entire surface is coated with a varnish 102 absorbing and / or reflecting laser radiation, which fills the recesses 98 of the relief structure. The lacquer 102 may be, for example, a high temperature resistant ultraviolet lacquer in which an infrared absorber is dispersed with a maximum absorption in the near infrared region of the spectrum. After application, the applied varnish is removed from the surface with a squeegee, removed with a roller or washed, and, as a rule, a thin tinting film that is inevitable with this technology remains on the bulges 96 of the relief structure. In general, a metallized relief structure with a lacquer coating 102 is obtained, which completely fills the recesses 98 of the relief structure and is present on the bulges 96 in the form of a thin tint film, as shown in FIG. 6 (a).

After being applied to the security paper 80, the film element 90 is exposed from the bottom side of the paper 80 through the through hole 82 by laser radiation, for example, radiation from an Nd: YAG laser, as shown by arrows 86 in FIG. 6 (a).

As a result of the action of laser radiation 86 on the lacquered metal coating 100, the metal coating on the convex portions 96 is removed, while in the recessed portions 98 it remains. This is because due to the presence in the varnish 102 of an additive that absorbs and / or reflects laser radiation, the laser energy in the recesses 98, reaching the metal coating 100, is not enough to cause demetallization at this point. On the contrary, sufficient energy is supplied to the metal coating of the bulge 96, covered only with a thin tint film, and it is removed. A thin tint film can even contribute to the removal of the metal coating, since often its absorption capacity is greater than the absorption capacity of the metal coating itself 100.

As a result of laser irradiation, the security document 110 shown in FIG. 6 (b) is formed, in which the demetallized bulges 96 in the region above the opening 82 are a laser-modified section 112 with a changed appearance, precisely aligned with the edges of the opening 82. The section formed by the recesses 98 , in the direction from the outside of the hole without any displacement continues to the portion of the hole 82. So, basically the appearance of the security document 110 corresponds to the image shown in Fig.5 (c). For example, the recesses 98 may form a sequence of letters "PL" and thus correspond to a subsection 66 of FIG. 5 (c), while a background hologram corresponding to a subsection 64 of FIG. 5 (c) can be encoded in the microstructure of the bulges 96.

Additional information and options for creating a specific pattern based on a metallized relief structure with bulges and recesses are described in patent application PCT / EP2009 / 00882, the contents of which are incorporated into this application by reference.

The embodiments illustrated in FIGS. 5 and 6 allow numerous variations and modifications resulting from the embodiments described in the aforementioned documents WO 2006/079489 A1 and PCT / EP2009 / 00882. For example, in contrast to the embodiment shown in FIG. 6, non-metalized depressions can also be provided with microrelief structures, or they can only provide recesses, but not bulges. In general, structures made using embossing varnish are recognizable without a metallic coating. However, if the refractive index of the varnish 102 shown in FIG. 6 is similar to the refractive index of the embossing varnish 94, then these structures can be made so that it is impossible to recognize them.

In other embodiments, no structures are provided on the metal coated portion. For this, for example, the structures (in accordance with FIG. 5) described in WO 2006/079489 can be chosen so that they are almost invisible to the naked eye, or the bulges and indentations (in accordance with FIG. 6) intended for metal coating removal, do not provide additional structures. As a result, in both cases, after removal of the metal coating, an appearance similar to that shown for the protective element 120 in Fig. 7 is obtained, when observed with the naked eye, the differently interacting subsections 122, 124 outside the through hole 126 look the same. The sub-sections 122, 124 can only be visually recognized within the opening 126, in which the first sub-sections 122 are modified by laser radiation and form a radiation-modified portion 128 with a changed appearance. To illustrate in FIG. 7, in the area 125 located outside the hole, some of the sub-sections 122, 124, which cannot be distinguished with the naked eye in this area, are indicated by hatching.

In the embodiments of FIG. 6, printing ink can also be used as a layer that absorbs laser radiation and prevents demetallization. As shown in the drawing with a view on the lower side of the security paper according to the invention (Fig. 8), as a result, the color pattern 130 can be seen on the lower side in the form of a laser-modified portion 112 precisely aligned with demetallization and through hole 82.

As for the layered structure, embodiments are possible in which the metal coating is located above the film and the film is above the printing ink, or the metal coating is located between the film and the printing ink, or the metal coating is located above the printing ink and the printing ink is above the film. In all three embodiments, the appearance corresponds to the appearance shown in FIG.

If, in the embodiment of FIG. 6, a laser-absorbing color varnish is selected, and some structure is created in this varnish, then a two-color negative pattern combined with a hologram or matte structure can be used. If at the same time the option is chosen in which the varnish protects the metal coating from laser radiation, then when observing from the upper side, the image shown in Fig. 5 (c) is visible, and when observing from the lower side, the image shown in Fig. 8.

Alternatively, they can choose an option in which, as described in more detail in PCT / EP2009 / 00882, the removal of the metal coating is supported by the varnish 102. The varnish used is preferably applied with a fairly thin layer so that it can easily create transparency. When using opaque varnish, the through hole effect would disappear.

The features described in connection with FIGS. 5 and 6 may be combined with each other. In this case, an additional design element may appear and / or disappear in the through hole in comparison with the surrounding area.

The proposed embodiments can be successfully applied in a micro-optical structure for displaying images, which can be performed, in particular, in the form of a moire magnifying structure, a micro-optical magnifying structure of the moire type, or a magnifying structure based on a modulo calculation. The basic principle of such image display structures is explained in WO 2009/000528 A1, the contents of which are incorporated herein by reference.

In the embodiment shown in FIG. 9, the film element 140 is applied by means of hot-melt adhesive 164 to the security paper 160 with a through hole 162. The film element 140 comprises a film substrate 142, the upper side of which is provided with a lattice structure of microlenses 144, which are on the upper side film substrates form a two-dimensional lattice with a pre-selected symmetry. Spherical or aspherical microlenses 144 preferably have a diameter of from 5 to 50 μm, in particular a diameter of only 10 to 35 μm.

On the underside of the film substrate 142, a pattern layer 146 is arranged, divided into a plurality of cells, and containing a pattern image having micro-blocking elements 148. Due to the arrangement of the cells in a certain order, a two-dimensional lattice with a pre-selected symmetry is also formed. The lattice period and the diameter of the lattice cells of the pattern image has the same order of magnitude as the lattice period and the diameter of the microlenses 144 cells, that is, they mainly comprise from 5 to 50 μm, in particular from 10 to 35 μm, therefore, with the naked eye elements 148 of microfocus, for example microlenses 144, it is impossible to recognize.

In the case of a moire magnifying structure, the lattice of cells with respect to its symmetry and / or magnitude of its parameters is slightly different from the lattice of microlenses 144, and depending on the type and magnitude of this deviation when observing the image of the pattern, an enlarged image of the microarray elements 148 appears using the moire structure. A generalized version are magnifying structures based on a modulo calculation, in which case the image of the pattern should not consist of a lattice of periodically repeating individual patterns. The principle of operation of magnifying structures based on a modulo calculation, and other information is disclosed in the aforementioned publication WO 2009/000528 A1.

In the embodiment shown in FIG. 9, the pattern layer 146 comprises an embossing varnish layer 150 with bulges 152 and recesses 154, which were first coated with a metal coating 156, as already described in principle in connection with FIG. 6. In the exemplary embodiment shown in FIG. 9, the microblock elements 148 are formed just by the recesses 154 in the embossing varnish layer 150.

As in the embodiment shown in FIG. 6, the metallized relief structure 150, 156 was coated with a laser-absorbing varnish 158, which fills the recesses 154, and forms a thin tint layer on the bulges 152. Then, the film element 140 was applied to the security paper 160, after which it was exposed to laser radiation from the lower side through the through hole 162. As a result of the bulge 152 in the area above the hole 162, it was demetallized with exact alignment, while the metal coating 156 in the recesses 154 remained . Outside the opening 162, the metal coating remains unchanged both on the bulges 152 and in the recesses 154.

In this case, in the finished security paper, the elements of micro-clogging 148 (recesses 154), enlarged by means of a moiré structure, can be observed upon observation of demetallized bulges 152 only within the opening 162, while outside the opening 162 due to the lack of contrast between the metallized recesses 154 and the metallized bulges 152 cannot recognize them.

So, in general, for the example embodiment of Fig. 9, the figure shown in Fig. 7 is obtained, but the sprockets 124 as micro-image elements 148 magnified by the moire structure in accordance with the selected magnifying effect when the security paper is tilted, move, for example in orthoparallactic relative to the direction of inclination Since the hole 162 served as a mask for demetallization of the bulges 152, the transition from an asterisk pattern 124 to a uniformly coated metal coating occurs exactly on the edge of the aperture 162 regardless of the inclination of the security paper.

If the embossing varnish layer 150 is additionally provided with a micro-relief structure, for example on bulges, then an appearance with a magnifying effect corresponding to FIG. 5 (c) can also be created. In this case, the letters "PL" move as a result of the magnifying effect, demetallization appears exactly at the boundary of the through hole. In this case, within the opening 162, the elements of the micro-block (recesses) enlarged by means of the moire structure are recognizable against the background of demetallized bulges; outside the hole 162 they are recognizable against the background of the microrelief structures of the bulges, which form, for example, a background hologram.

If a color varnish that absorbs laser radiation is selected (Fig. 9), then those embodiments that have already been discussed in connection with Figs. 5 and 6 can also be implemented in the case of micro-optical structures for display. If the back side of the film substrate is also equipped with lenses, then the back sides can also be transformed as a result of the magnifying effect.

In addition, demetallized areas can be located with the overlap of the microstructures, so that in the zone of the through hole there is a negative pattern formed by demetallized areas located in the form of a pattern inside the metal coating. The areas demetallized in the form of a pattern can be made in the form of a geometric pattern or in the form of an alphanumeric string.

Figure 10 shows another example of the implementation of the moire magnifying structure 170, which is generally arranged in the same way as the micro-optical magnifying structure shown in Fig. 9, and in these drawings the elements corresponding to each other are denoted by the same reference numbers. When observing the moire magnifying structure 170 shown in FIG. 10, both within and outside the opening 162, micro-clutch elements 174, 176 that are magnified by the moiré structure can be recognized, but they produce different color impressions.

In this embodiment, the image of the magnifying structure pattern consists of a colored layer 172 with a pattern image, which contains micro-tracer elements 174, wherein the color of the layer 172 may change as a result of laser radiation. For this, the pattern layer 172, for example, may contain laser-modified pigments with special effects that are available to specialists and have various properties, in particular with respect to their color, color change under the influence of the laser, threshold energy and the desired laser wavelength .

Initially, after applying a film element with a layer 172 containing a patterned image onto the security paper 160, all of the micro-jam elements 174 have the same original color. Then, as a result of exposure to laser radiation through the hole 162 from the underside of the security paper 160 in the pattern layer 172 with exact alignment in the area of the hole 162, a color change is caused, so that the micro-stop elements 176 located at this place change their color. Therefore, when observing the magnifying structure 170, a combination of the moiré-enlarged elements of the first microcausal element 174 of the first color outside the hole and the enlarged elements 176 of the microcausor of the second color within the hole is visible.

Along with the transition of the first color to the second color, the color change may consist in the transition of a transparent layer with a picture of a pattern into a color layer with a picture of a pattern or discoloration of a color layer with a picture of a pattern. In the second case, a color magnifying effect occurs, visible only in the hole and precisely aligned with the hole, in the latter case, the magnifying effect, which is visible only outside the hole and ends exactly at the edges of the hole.

To change the color or discoloration of the varnish, it is not necessary to use laser radiation, a color change can also be caused by ultraviolet or infrared radiation. So that in these embodiments, the varnish does not discolor as a result of the action of daytime color, the film substrate 142 and / or varnish of microlenses 144 are preferably provided with appropriate absorbers of ultraviolet or infrared rays.

11 illustrates another embodiment of the invention in which, in the micro-optical image display structure 180, a change in the displayed image of the pattern occurs exactly at the edges of the through hole 162 of the security paper 160.

Outside the through hole 162, a first image of the pattern can be seen, which, as shown in the top view (FIG. 11 (b)), consists of the first microfuser elements 182 enlarged using the moire structure as a sequence of numbers “50”. Thus, the first elements 182 of the microcircuit receive information through holes 162, which is also formed by the sequence of numbers "50".

Within the through-hole 162, a second image of the pattern can be seen, which consists of the second microfuser elements 184 enlarged by the moire structure in the form of the euro symbol “€”. So, the first and second elements of the microcurrent 182, 184 and, accordingly, the hole 162 and the second elements 184 of the microcurrent in each case complement each other, forming the designation of the nominal value of the banknote "50 €". The transition from the first image of the pattern to the second image of the pattern occurs with precise alignment on the edge of the through hole 162.

In order to create an exact alignment of the image change, as shown in FIG. 11, a film element 190 is used in which a two-layer coating system is located on the underside of the film substrate 196, consisting of two varnish layers 192, 194 arranged one above the other having the same refractive index. At the same time, the first elements of microfibre 182 exist in the form of embossed structures in the upper (when viewed from the side of the film substrate 196) lacquer layer 192, and the second elements 184 of microfuser in the form of embossed structures in the lower (when viewed from the side of the film substrate 196), varnish layer 194 . The opposite side of the film substrate 196, as described above, is provided with a grating of microlenses 144, which is precisely matched with the grating of the microstrain elements 182, 184.

In the area of the hole 162, the topcoat lacquer 192 of the varnish system was precisely aligned as a result of laser radiation acting on the film element 190 through the hole 162 on the underside of the security paper 160. Therefore, when observing the area adjacent to the hole 162, through the microlenses 144 within the hole, see only the second elements 184 of the microcurrent in the lower varnish layer 194 in the form of the symbol “€” (Fig. 11 (b)).

Outside the hole 162, both varnish layers 192, 194 are located directly above each other. Since they have the same refractive index, the embossed structures 184 on the boundary surface of the lacquer layers 192, 194 do not affect the transmitted light, so that outside the opening 162, the second microfuser elements 184 cannot be recognized. On the contrary, at this point only the first elements 182 of the microzill appear in the form of a sequence of numbers “50”, which can be recognized due to the difference in the refractive indices on the boundary surface between the top layer 192 of the varnish and the adjacent layer 198, for example, a layer of thermal varnish. If the layer 198 is colored, then outside the opening 162, the first micro-blocking elements 182 appear in color, and the second micro-blocking elements 184 within the opening 162 are transparent.

At the same time, the top layer of varnish 192 is made in the form of a thin layer, so that both the first 182 and second 184 elements of the micro-tracer essentially lie in the focus of the microlenses 144 and, when observed, give a focused image.

For a simplified presentation in FIG. 11 (a), the first elements 182 and the second elements 184 of the microcavity are congruent, in practice they lie, generally, not directly above each other.

In other embodiments, the security element disposed on the film element is formed on the basis of a combination of microlenses and concave micro-reflectors to form a micro-optical display structure visible both above and below.

In accordance with a schematic sectional view (shown in FIG. 12), such a security element 201, for example, located on a banknote, has a substrate 203, on the upper side 204 of which there are embossed microstructures 205, and on the lower side 207 several located in some areas concave microreflectors 208 and several microlenses 209. Concave microreflectors 208 and microlenses 209 are located in a plane perpendicular to the plane of the drawing (Fig. 12), forming a lattice of a certain geometry, for example, a hexagonal lattice in area in the pattern e ementov for observation.

Substrate 203 comprises a polyethylene terephthalate film 210 on which a first radiation curable varnish layer 211 containing microstructures 205 is deposited. On the lower side of the polyethylene terephthalate film 210 a second layer 212 is made of radiation curable varnish, in which the negative shape of the concave micro-reflectors 208 and the shape are embossed microlenses 209.

The microstructures 205, forming a microstructural object or microcracker M1, are also located in a plane perpendicular to the plane of the drawing (Fig. 12), forming a lattice of a certain geometry, in this case, for example, also a hexagonal lattice, that is, over the entire surface in a fine structure pattern, moreover the fine structure pattern is consistent with the pattern of the elements for observation, and both patterns are oriented relative to each other so that when observing the protective element 201 from the upper side (in the direction of arrow P1) of the microstructure 205 together with These microreflectors 208 form a magnifying structure based on a modulo calculation, or a moire magnifying structure, as described in more detail in the aforementioned publications WO 2009/000528 A1 and WO 2006/087138 A1. Moreover, this microstructural object M1 corresponds to the image of the pattern as described in WO 2009/000528 A1. When observing in the direction of the upper side (in the direction of arrow P1), the observer can distinguish an enlarged microstructural object M1 as a security feature (a given image in the sense of WO 2009/000528 A1).

For the manufacture of concave micro-reflectors 208, that side of the second layer 212, which is directed to the opposite side from the polyethylene terephthalate film 210, in section A is provided with a reflective layer 213, in particular a metal coating, so that the concave micro-reflectors 208 are made in the form of reflectors with a rear reflective surface. In this embodiment, the inner side of the reflective layer 213 of each concave micro-reflectors 208 or the embossed shape for the concave micro-reflectors 208 has a spherical shape with a radius of curvature of 38 μm and a height of approximately 3 μm. The thickness of the second layer 212, the polyethylene terephthalate film 210, and the first layer 211 is selected so that the microstructures 205 are just 19 μm from the concave micro-reflectors, i.e., in the focal plane of the concave micro-reflectors 208, so that the required enlarged image of the microstructures 205 is created to create a security feature .

In the portion B of the protective element 201, the metal coating 213 was removed as a result of demetallization, so that the embossed forms at this point do not form concave micro-reflectors, but micro lenses 209. The radius of curvature of the convex side 214 of the micro lens 209 is the same as in the case of concave micro-reflectors 208, such thus, in this embodiment, it is 38 μm, which leads to a focal length of microlenses of 209 of approximately 115 μm. So, the focus plane E of the microlenses 209 lies outside the protective element 201, therefore, the microstructures 205 in the area B, when viewed from the lower side 207 of the protective element 201 (in the direction of the arrow P2), cannot be recognized.

The microlenses 209 are not intended to display microstructures 205, but to verify another banknote or to self-verify a banknote with a security element 201. For self-verification, an additional microstructural object (not shown in the drawing) is present on the banknote in a position that is laterally located at a distance from of the security element 201, by folding or folding the banknotes are positioned in the E plane in front of the upper side 204 of the substrate 203 of the security element 201, so that when observing the lower side 207 and using microlenses 209, an additional microstructural object is displayed with an increase.

To verify another banknote, an additional microstructural image of another banknote is placed in the E plane in front of the upper side 204 of the security element 201, so that using microlenses 209 to create an enlarged image through the lower side 207, so that another banknote can be verified.

As described in detail above, in accordance with the invention, the removal of the metal coating 213 is carried out after applying the security element 201 to the security paper with a through hole, by exposing the metal coating 213 to the bottom side 207 of the security element 201 through the through hole in the security paper by radiation. Thus, it is ensured that the transition from microreflectors 208 to microlenses 209 (the boundary between sections A and B in FIG. 12) occurs with precise alignment at the edge of the through hole.

Concave microreflectors 208 and microlenses 209 can also be formed in different planes, as shown in sectional view (Fig. 13). The structure of the layers 210-212 corresponds to the structure shown in Fig.12, and in Fig.13 provided with a continuous metal coating 213 and covered with a reflective layer, the sides of the concave micro-reflectors 208 are indicated by continuous lines (section A). In section B, the metal coating 213 is partially removed under the influence of radiation, so that translucent concave micro-reflectors 208 'arise at this point, which are indicated by dashed lines in Fig. 13. Moreover, in particular, a substructure is applied to the metal coating, for example a dot or line grating, and in separate sub-areas it is completely removed in accordance with this substructure, so that a translucent metal coating generally appears.

A second polyethylene terephthalate film 222 with an ultraviolet varnish layer 223 formed on it is glued onto the layer 212 with the aid of laminating adhesive 221, and the convex sides 214 of the microlenses 209 are embossed in the layer 223 of the ultraviolet varnish. The convex sides 214 have the shape of a spherical segment with a radius of curvature of 18 μm. Since the radius of curvature of the convex sides 214 of the microlenses 209 is 18 μm, the focal length of the microlenses 209 is 54 μm, which at the selected layer thickness just corresponds to the distance between the apex of the convex sides 214 and the microstructures 205.

In this embodiment, the removal of the metal coating 213 is also carried out after applying the security element 201 to the security paper with a through hole by exposing the metal coating 213 to the bottom side 207 of the security element 201 through radiation through the security paper and the second polyethylene terephthalate film 222, as described in detail reviewed above. As a result, with exact alignment with the edges of the through hole, a transition is created from the micro-reflectors 208, completely covered with a metal layer, to the translucent concave micro-reflectors 208 '(the boundary between zones A and B in Fig. 13).

In this case, outside the hole (section A), the observer, when viewed from above (in the direction P1) through the reflecting micro-reflectors 208, completely covered with a metal layer, can see the microstructures 205. Within the hole (section B), the microstructures 205 can see both above and below namely, once (observation direction P1) as a result of reflection from the translucent concave micro-reflectors 208 'and again (observation direction P2) through the microlenses 209 and the translucent concave micro-reflectors 208'.

Other information and advantages of such a combination of microlenses and concave microreflectors can be found in German patent application DE 102009022612.5, the contents of which are incorporated into this description by reference.

If the film element is applied to the security paper using hot-melt adhesive or other glue, then due to tolerances on the combination of hot-melt adhesive 84, it may slightly spread into the area of hole 82, for example, as shown in FIG. 6. This can lead to a slightly cloudy appearance in the area adjacent to the through hole. Therefore, in all embodiments of the invention, the adhesive can be laser-removed glue so that it can be applied over the entire surface, and then, when modified with a laser, removed in the area of hole 82. After that, the adhesive layer is aligned with the edges of the hole in the same way. as, for example, shown in Fig. 11 (a) for the hot-melt adhesive layer 198. To this end, appropriate laser absorbers are preferably added to the adhesive.

Instead of the simple metal coating described and shown for illustration in embodiments of the invention, multilayer layer systems can be used. By choosing the laser parameters accordingly, in the area of the hole, individual layers of such a system can be removed. For example, in the case of a thin film element with a color changing effect, which usually consists of a reflective layer, a dielectric separation layer and an absorbing layer, only a reflective layer or only an absorbing layer can be removed by laser irradiation.

Of course, the described modifications can be applied not only in the case of security papers, but also in other data carriers with through holes, for example, in polymer banknotes or banknotes with a multilayer film. If only one film is treated with a laser, the second film must be transparent to laser radiation, or a second film is not applied before the laser treatment operation.

List of item numbers

10 bank note 12 banknote paper fourteen through hole 16 down side eighteen upper side twenty film strip 22 hologram 24 laser-modified area thirty film strip 32 hologram in natural colors 34 Mountain chain 36 sky 38 laser-modified area 40 security paper 42 through hole 44 surrounding area 46 down side 47 upper side 48 adjoining area fifty design 52 painted areas 60 film element 62 security element 64.66 sub-sections 70 security paper 72 through hole 74 laser-modified area 80 security paper 82 through hole 90 film element 92 film substrate 94 stamping varnish coat 96 bulges 98 recesses one hundred metal coating 102 laser absorbing varnish 110 secure document 112 laser-modified area 120 security element 122, 124 sub-sections 125 outside zone 126 through hole 128 radiation modified area 130 color pattern 140 film element 142 film substrate 144 microlenses 146 pattern layer 148 micro-clog elements 150 stamping varnish coat 152 bulges 154 recesses 156 metal coating 158 laser absorbing varnish 160 security paper 162 through hole 162 linearly polarizing layer 164 hot glue 170 moire magnifying structure 172 pattern layer 174, 176 micro-clog elements 180 micro-optical display structure 182, 184 micro-clog elements 190 film element 192, 194 layers of varnish 196 film substrate 198 adjoining layer 201 security element 203 substrate 204 upper side 205 microstructures 206 down side 208 concave microreflectors 208 ' translucent concave micro-reflectors 209 microlenses 210 polyethylene terephthalate film 211 radiation curable varnish 212 radiation curable varnish 213 metal coating 214 convex side of microlenses 221 adhesive for lamination 222 polyethylene terephthalate film 223 a layer of ultraviolet varnish.

Claims (29)

1. A storage medium, in particular a valuable or secure document, containing:
a window extending from the lower side to the upper side of the data medium; a film element with a protective element covering the window on the upper side of the data carrier, wherein one part of the protective element is located above the window, and one part of the protective element is located next to the window, characterized in that the part of the protective element that is located above the window has a section, modifiable under the influence of radiation, combined with the window, moreover, in the indicated area, the appearance of the protective element is modified under the influence of electromagnetic radiation. 2. The data carrier according to claim 1, characterized in that the protective element has a metal layer demetallized in the area modified by radiation. 3. The data carrier according to claim 2, characterized in that the protective element comprises a metallized diffraction structure, a metallized reflective diffraction structure, a metallized matte structure or a thin film element with a color-changing effect. 4. The storage medium of claim 1, characterized in that the protective element has first and second sub-sections, interacting differently with electromagnetic radiation, both the first sub-sections and the second sub-sections partially located above the window, and partially next to the window. 5. The data carrier according to claim 4, characterized in that the area, modified by radiation, contains only the first sub-sections and does not contain second sub-sections, so that the second sub-sections located above the window and next to the window have the same appearance. 6. The data carrier according to claim 4, characterized in that at least one of the two subareas has an interference structure, preferably a relief structure in the form of a lattice, which is determined by the lattice constant and the orientation of the lattice strokes. 7. The data carrier according to claim 4, characterized in that at least one of the two subareas has a relief structure that increases the surface area. 8. The data carrier according to claim 4, characterized in that the first and second sub-sections are formed by bulges and recesses of the embossed structure. 9. The data carrier according to claim 8, characterized in that the recesses are filled with a coating layer reflecting and / or absorbing radiation. 10. The data carrier according to claim 1, characterized in that the protective element contains microstructures with a stroke thickness of from about 1 μm to about 10 μm, the appearance of which in the area modified by radiation is changed. 11. The storage medium according to claim 10, characterized in that the microstructures at least in the area modified by radiation form an image of a pattern divided into cells, in each of which there are sections of a given image, and the sizes of the image sections in the lateral direction are preferably make up from about 5 microns to about 50 microns, in particular from about 10 microns to about 35 microns. 12. The storage medium according to claim 10, characterized in that an observation grating is provided, consisting of a plurality of grating elements for reproducing a predetermined image when observing a pattern image using an observation grating, and in the lateral direction, the dimensions of the viewing grating elements are preferably from approximately 5 microns to about 50 microns, in particular from about 10 microns to about 35 microns. 13. The storage medium according to claim 10, characterized in that the color of the microstructures is changed in the area modified by radiation. 14. The data carrier according to claim 10, characterized in that the microstructures located inside and outside the area, modified by radiation, in each case represent a different pattern, in particular different patterns, signs or codes. 15. The data carrier according to claim 10, characterized in that the microstructures are located in a two-layer varnishing system containing two layers of varnish located on top of one another, having essentially the same refractive index, the second image of the pattern being embossed in the lower layer of varnish and the first image of the pattern stamped in the upper layer of varnish located above the lower layer of varnish, and the upper layer of varnish removed in the area modified by radiation, so that inside the area modified by radiation, the visual recognizable second pattern of the lower layer of lacquer and the outside portion to be modified under the influence of radiation, visually perceptible pattern first upper layer of lacquer. 16. The storage medium according to claim 1, characterized in that the protective element contains several reflective first elements for displaying micro images located over the area in the structure of elements for observation, and transmitting second elements for displaying micro images over the area in the pattern of elements for observation;
moreover, the first elements for displaying the microimage are located inside, and the second elements for displaying the microimage are outside the area modified by radiation;
moreover, the protective element also contains a microstructural object containing several microstructures, which are located in the microcircuit, consistent with the pattern of elements for observation so that the microstructural object through the first elements of the microimage is displayed in an enlarged view in front of the upper side;
moreover, with the second elements for displaying the microimage, the area of the object plane is located outside the protective element, so that the microstructures of the microstructural object are not perceptible from the bottom side when observed by the second elements for reproducing the microimage, but for verification, an additional microstructural object containing several microstructures, so that by means of the second elements of the microimage additional microstructural The subject is displayed enlarged in front of the underside. 17. The data carrier according to clause 16, wherein the first elements for displaying a microimage are made in the form of concave microreflectors and / or the second elements for displaying a microimage are made in the form of microlenses. 18. The storage medium according to claim 1, characterized in that the window is made in the form of a pattern, characters or codes. 19. The data carrier according to claim 1, characterized in that the window is formed by a through hole extending from the lower side to the upper side of the data carrier. 20. The data carrier according to claim 1, characterized in that the window is formed by a transparent portion of the data medium extending from the lower side to the upper side of the data medium. 21. The storage medium according to claim 1, characterized in that the storage medium consists of several layers, and the window contains a through hole in at least one layer of the storage medium. 22. The data carrier according to PP 19 or 21, characterized in that the through hole is formed by a linear grid of many parallel cutting lines. 23. The data carrier according to claim 1, characterized in that the area, modified by exposure to radiation, is made in the form of a pattern, characters or codes. 24. The data carrier according to claim 1, characterized in that the film element is deposited on the upper side of the data carrier by means of an adhesive layer removed by means of a laser, and the adhesive layer removed by means of a laser is removed in a window region. 25. A method of manufacturing a data carrier, comprising the following steps:
a) take the substrate of the data carrier having a window extending from the lower side to the upper side of the substrate of the data carrier and a film element with a protective element;
b) cover the window on the upper side of the substrate of the data carrier with a film element so that part of the security element is located above the window, and part of the security element is located next to the window;
c) act on the protective element by electromagnetic radiation from the lower side of the substrate of the data carrier and through the window to modify the appearance of the protective element on the section modified above the window by radiation. 26. The method according A.25, characterized in that in step c) the protective element is exposed to laser radiation, in particular ultraviolet radiation, radiation in the visible region of the spectrum or radiation in the near infrared region of the spectrum with a wavelength of up to 1.5 microns. 27. The method according A.25, characterized in that in step b) the film element is applied to the upper side of the data carrier by means of a laser-removable adhesive, and in step c) the laser-removable adhesive in the window area is removed. 28. The method according A.25, characterized in that the window is formed by a through hole or the data carrier consists of several layers, and the window contains a through hole in at least one layer of the data carrier, and that in step a) the through hole is made in a substrate or a layer of a data carrier containing a through hole, by cutting or laser cutting with a cutting laser, preferably with a wavelength of approximately 10.6 μm. 29. The method according to p, characterized in that
the substrate or layer of the data carrier is provided with a laser-modifiable indicator substance at least in the vicinity of the through hole to be created;
a through hole is provided in the substrate of the data carrier or in the layer of the data carrier by means of laser radiation;
the laser-modifiable substance is modified near the hole by laser radiation.

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