EP2252470B1 - Print layer comprising main pixels and satellite pixels on a polymer layer composite for a security and/or valuable document - Google Patents

Description

Field of the invention

The present invention relates to a polymer layer composite for a security and / or value document and to a method for its production. Furthermore, the invention relates to a security and / or value document which can be produced from the polymer layer composite according to the invention, for example by welding the composite into transparent protective films. Moreover, the invention relates to the use of the security and / or value document as identity card, passport, credit card, bank card, cash card, customer card, Visa card, ID card or driver's license.

Prior art and background of the invention

Card-shaped data carriers are used, for example, for the identification of persons and / or objects and / or for cashless payment transactions. You have u.a. visually identifiable features that they clearly assign to a person and / or an item and / or a money or securities account and only allow the owner to identify himself or to dispose of the item or account and arrange for money transfers. For this reason, these data carriers must have security features that make it virtually impossible for unauthorized persons to falsify or falsify the cards, so that abuse can be prevented as much as possible. In addition, a fake should therefore be easily recognizable.

To protect against counterfeiting or falsification has been proposed for the known card-shaped disk so far a variety of security features and have been implemented, such as guilloches, watermarks, stamps, Durchlichtpasser, passport photos produced by laser engraving, holograms, tilts, fluorescent labels and various other features. These features are intended serve to complicate a forgery or even make it virtually impossible. For this purpose, it should be extremely difficult to reproduce these features.

Essential security features in the card-shaped data carriers are personalized and / or individualized features that are stored in the data carrier. Personalized features are, for example, passport photos and data of the person to whom the card is associated, such as date of birth, address or identification number in a company, as well as biometric data such as a digitized record of fingerprints or the size, or the person's eye color or affiliation health insurance. Individualized features are data associated with a particular device such as a motor vehicle, a bank account, or a security.

Such personalized and / or individualized features are applied individually to the card-shaped data carriers for the person using them. Therefore, the process for their generation must be flexible. For example, methods and apparatus for applying such data to card-shaped data carriers are known in the art US 6,022,429 A . US 6,264,296 B1 . US 6,685,312 B2 . US 6,932,527 B2 . US Pat. No. 6,979,141 B1 and US 7,037,013 B2 , wherein the personalized and / or individualized features can be applied to the cards, inter alia, by means of inkjet printing technology. Some of the abovementioned documents also state that these data are coated after application with a protective film.

In EP 0 384 274 A2 a method for producing a multi-layer ID card is described in which security-specific data are introduced with an ink-jet printing process. The point overlap compensated error diffusion method is used. As an additional safety effect, the compensation of the point overlap depends on the point size and the dot shape.

For ink-jet printing or other method of drop-on-demand printing, it has also been reported that satellite pixels may be generated in addition to the main printing pixels produced in printing. Such satellite pixels are avoided at a pressure to produce a perfect print image. Thus, droplet formation not only forms a uniform droplet, but occurs depending on the ink properties and the conditions under which the droplets are formed (for example, the flank shape of the droplet ejection from the pressure nozzle determining electrical signal to drive the nozzle; or bubble jet actuator), more or less long "drop tails" whose velocity is smaller than that of the leading drops and from which therefore further successive satellite drops can form ( H.Wijshoff in: "Drop formation mechanisms in piezo-acoustic inkjet", available at http://www.flow3d.com/pdfs/tp/micro_tp/FloSci-Bib01-07.pdf on 8.2.2008 ). Therefore, these satellite drops are delayed and, due to the movement of the printhead relative to the print medium, strike the print medium with an offset from the center of the main drop when no optimization measures are taken. With sufficient offset of both drops, a main pixel and a (usually smaller) satellite pixel form on the print medium.

To reduce or minimize the formation of such satellite drops, it is out US 2003/0179258 A1 It is known that the formation of the satellite drops can be reduced or minimized by providing a plate with channels in front of the device on the printhead from which the ink droplets emerge. This plate is formed and arranged to vary the trajectories of the satellite drops emerging from the printhead while ejecting the major drops substantially unaltered in the main direction. This allows a targeted influence on the trajectories of the satellite drops relative to those of the main drops, so that the occurrence of satellite pixels can be reduced or avoided.

In US 7,093,915 B2 will also indicate how the direction in which a satellite drop following a main drop can be changed from the direction in which the main drop exits the print head such that the satellite drop at a given relative speed of the print head to the print medium, distance of the print head from the print medium and airspeeds in the main pixel impinges on the print medium.

Furthermore, it is off DE 199 00 856 A1 a method for encoding a primary image with a secondary image is known in which the primary image and the secondary image are rasterized. The secondary image is hidden in the primary image by being compensated for with its own inverse representation. For combining both images (primary image and secondary image compensated by its own inverse representation by compensation), a coding method is used in which the points of the rasterized primary image can be modified or changed so that the balanced secondary image in the primary image is invisible. For this, the points in the primary image are grouped and the information of the secondary image is fed into these point groups. Such variations may be in the density, shape and shape, angle, position, size, or frequency of the individual points in the point groups.

Furthermore, it is off DE 197 06 008 C2 a method for increasing the security against forgery of variable graphic elements, in particular alphanumeric characters, images, barcodes, specified in value and security documents, wherein at least the surfaces of the variable graphic elements are provided with microscopic fine structures and in which between spectral and / or geometric properties of the structures in terms of color and pattern and the variable graphic elements to be protected a defined context in the form of a code is made. For example, a color information of the graphic structure is proposed as a security feature. In particular, color codes can be defined for alphanumeric characters, which recur in the structures of the individual elements. In the example shown there, the letter "c" is changed on the letter surface by picking up a c-shaped strip, which is a protective structure. The letter is assigned a color identical to the color of the protective structure in the "c".

High-quality card-shaped data carriers today consist in particular of polycarbonate. Personalization and / or customization of polycarbonate-based cards typically takes place by laser engraving. A laser beam is focused into the material and guided over the material. In the process, the laser beam produces pungencies in the interior through pyrolysis, which vary in intensity depending on the laser intensity and duration at the respective points. Thus, an image or other graphics or even a lettering or a number and / or letter combination can be generated.

However, it is not possible with this method to produce colored images or graphics and font or number sequences, but only black / white representations. At most, it is also possible to some extent to produce gray tones / levels. Therefore, there has been no lack of further attempts to produce colored representations by means of printing techniques in the maps. However, this has turned out to be problematic since the usable printing inks are not sufficient for the design of the cards are suitable. For a color print produced on a polymer film sometimes leads to subsequent assembly, for example lamination, this film with other films at internal pressure that the thus produced laminated or otherwise assembled film stack by manipulation in the position in which the print layer is arranged, possibly can be delaminated again. Depending on the chemical nature of the ink, incompatibilities show up, which manifest themselves in the form of a lack of adhesion. In particular, water-based inks can easily be scraped off on a large number of polymers (eg polyolefins, polyesters, polycarbonates) and thus cause problems even before joining. However, such a vulnerability in the security and / or value document is unacceptable because it facilitates forgery or falsification of the document.

Technical problem of the invention

Therefore, the present invention is based initially on the problem that a layer composite with personalized and / or individualized features that have been produced by printing, may be delaminated or split by unauthorized manipulation, so that it is desirable to find a method with this is certainly prevented.

In addition, there have been many attempts in the past to find methods that are suitable for providing novel security features contained in a polymer layer composite, especially on a polycarbonate basis. The present invention is therefore based on the further object of finding novel security features for security and / or value documents whose forgery or falsification is virtually ruled out.

Brief description of the invention

Insofar as the term "representation" is used in the description and in the claims, this is to be understood as meaning both a print reproduction which is structured in some way and a print reproduction over the entire surface. Structured print reproduction can be, for example, an image, such as a passport photograph, or a graphic print reproduction, for example guilloches or a background screening, or alphanumeric Characters or a one-dimensional or two-dimensional barcode or emblem, coats of arms, national emblems or any other print reproduction.

As used in the specification and claims, the term "pixel" means the smallest possible element in printing a rasterized image. Pixels usually have simple geometric shapes, such as circles or squares. In ink-jet printing, usually circular or circular shapes are generated which are defined by the ink spot spreading in the printing medium. The entirety of all pixels of an image forms a representation in their relative arrangement to one another.

As used in the specification and claims, the term "satellite pixel" is to be understood as an ink stain on the print medium which, in a drop-dot based printing process, under certain conditions, in addition to the actual main ink spot, the main pixel. A satellite pixel is associated with a main pixel and therefore has a close spatial relationship with it. Thus, the satellite pixel is typically very close to the main pixel and may ideally merge with it or be separated therefrom if additional satellite pixels are to be generated and the satellite pixels are formed at a greater distance from the main pixel. Optionally, then a bimodal pixel of main pixel and satellite pixel arises when the distance between the main pixel and satellite pixel is not very small, but on the other hand, not so large that both pixels are separated. Satellite pixels are characterized, inter alia, by being in a fixed geometric relationship relative to the main pixels to which they are associated, for example by always being on the connecting line between adjacent main pixels or appearing at a certain angle to that connecting line, if not spattering of printing ink, which statistically produce ink stains. If the printing direction (relative direction of movement between the printing head and the printing medium) is reversed, this angle is also mirrored on a perpendicular to the printing direction. However, it can also be provided that certain print pixels composed of main pixels and satellite pixels, for example pixels in a specific color and / or size, are in a first spatial orientation and other pixels, for example in a different color and / or size, in one varying geometric relationship. Thus, you can the main and satellite pixels in adjacent main pixel satellite pixel ensembles may also be arranged in a different geometric arrangement relative to one another, wherein only ensembles with the same geometric orientation occur within a group. Thus, adjacent ensembles can also appear in different geometric orientations, provided that they belong to different groups. An essential feature of satellite pixels is that they are typically smaller than the major pixels to which they are associated.

As used in the description and in the claims, the term "digital printing method" is to be understood as a printing method in which the data required for imaging digitally created and printing directly, as in the inkjet printing process, or indirectly, as in a xerographic printing process can be used to produce the printed image without the need for an explicit printing plate. This is a non-impact printing process, i. a method in which no solid printing form (a printing cylinder or a stamp) is used.

To produce novel counterfeiting and tamper-proof security features, a polymer layer composite for a security and / or value document, for example for a credit card, bank card, cash card, customer card, visa card, ID card or driver's license, passport, identity card, is proposed according to the invention, which comprises at least two having cohesively interconnected polymer layers, wherein on at least one surface of at least one of the polymer layers each consisting of printing pixels pressure layers are formed in a pressure range. In accordance with the invention, the print pixels each consist of a main pixel and at least one satellite pixel assigned to the main pixel.

Such a polymer layer composite is produced according to the invention using the following method steps: (a) providing the polymer layers for the polymer layer composite; (b) forming respective print layers of print pixels on at least one surface of at least one of the polymer layers in a print area; In this case, the print pixels are each formed from a main pixel and at least one satellite pixel associated with the main pixel; and (c) bonding the polymer layers together.

The starting point of the present invention is the recognition that novel security features in security and / or value documents can be generated if pixel-oriented printing methods are used and the individual screen dots of a screened representation, in particular of personalized and / or individualized features, are modified in such a way that respectively a main pixel and satellite pixels associated therewith are generated. The entire representation is then preferably composed of main pixels and associated with them satellite pixels.

Usually, pixel-oriented printing methods, in particular the inkjet printing method, are set up such that the respectively printed pixels have the most reproducible shapes, areas and color densities. For this purpose, the print is optimized so that no satellite pixels form. Each printing pixel then ideally consists of a circular surface. Therefore, the presence of satellite pixels, in addition to the main pixels to which they are associated, constitutes a security feature in the security and / or value document. Thus, if no such satellite pixels are detected in a security and / or value document, even though the standard document is printed with such pixel shapes it is easy to identify a forgery or falsification.

It has already been stated above that satellite pixels are smaller than the main pixels to which they are assigned. With respect to the relative diameter of the two pixel types, reference is made to the above definition.

Typically, each generated main pixel in the representation may be associated with a single satellite pixel. This results from suitable electronic control of the print head. In particular, the rising edge of the actuator (piezoelectric crystal, resistance heating in the bubble jet inkjet printer) is optimized, with the single ink drops are ejected from the print head. This is because the main part of a drop is ejected from a discharge port in the print head at a high speed, but a smaller part still leaks when the discharge operation is actually already completed and the meniscus of the ink liquid in the discharge port is already starting to retire ( "fill-before-fire action"). In this stage emerging ink liquid is delayed from the leading liquid parts, so that forms a liquid path, which is sufficient Delay is pulled far apart and then in the trailing part (tail) under certain conditions and individual drops (satellite drops) can form. These additional parameters for satellite drop generation are due, among other things, to the composition of the ink, especially with regard to its viscosity and surface tension, which have a significant influence on the formation of satellite drops that produce satellite pixels. For example, a high surface tension of the ink liquid to air is advantageous for the formation of individual ink droplets. The inertia of the ink fluid also has a significant influence. This is shown in detail in H.Wijshoff, ibid., In more detail.

The security feature that can be produced with the invention can be realized in an arbitrarily designed representation: It can be structured, such as an image, for example a passport photograph, or as a graphic, such as guilloche, or as a raster, in particular a background raster (for example diamond, hahnentritt -, pepita-, herringbone, checkerboard-shaped screening), or as alphanumeric characters, for example for the representation of personalized data of the holder or the marked object (for example motor vehicle), or as a barcode or as an emblem, coats of arms, insignia, a flag, a test mark, warranty, seal. Basically, other structured representations are possible. Furthermore, the representation can also be just a uniformly colored surface without structure, such as a white, black, gray or somehow colored surface.

Within the representation, all or only certain, uniquely identifiable groups of print pixels can be embodied as main pixel satellite pixel ensembles. For example, all print pixels that are not black may be provided with satellite pixels.

Detailed description of the invention

The present invention relates to a composite of polymer layers, which may optionally also contain layers of other materials, such as cardboard, paper, textiles, fabrics, knitted or prepregs, for the production of security and / or value documents.

In principle, all materials customary in the field of security and / or value documents can be used as materials for the polymer layers. The polymer layers can, identically or differently, be based on a polymer material from the group comprising PC (polycarbonate, especially bisphenol A polycarbonate), PET (polyethylene glycol terephthalate), PMMA (polymethyl methacrylate), TPU (thermoplastic polyurethane elastomers), PE (polyethylene), PP (Polypropylene), PI (polyimide or poly-trans-isoprene), PVC (polyvinyl chloride) and copolymers of such polymers. Furthermore, coextruded films of these materials can be used. Preference is given to the use of PC materials, whereby, for example, but by no means necessarily, so-called low-T _g polycarbonate-based materials can also be used, in particular for a polymer layer on which a printing layer is applied, and / or for a polymer layer, which is bonded to a polymer layer bearing a print layer on the side of the print layer. Low-T _g materials are polymers whose glass transition temperature is below 140 ° C.

The polymer layers can be filled or unfilled. The filled polymer layers contain in particular color pigments or other fillers. The polymer layers may also be dyed with dyes or colorless and, in the latter case, transparent, translucent or opaque.

It is preferred if the base polymer of at least one of the polymer layers to be joined contains identical or different mutually reactive groups, wherein react at a laminating temperature of less than 200 ° C reactive groups of a first polymer layer with each other and / or with reactive groups of a second polymer layer. As a result, the lamination temperature can be lowered without jeopardizing the intimate bond of the laminated layers. In the case of various polymer layers having reactive groups, this is due to the fact that the various polymer layers can no longer be readily delaminated due to the reaction of the respective reactive groups. Because between the polymer layers takes place a reactive coupling, as it were a reactive lamination. Furthermore, due to the lower lamination temperature, it is possible to prevent a change in a colored printing layer, in particular a color change, from being prevented. It is advantageous if the glass transition temperature T _{g of} the at least one polymer layer before the thermal lamination is less than 120 ° C. (or even less than 110 ° C. or less than 100 ° C.). is, wherein the glass transition temperature of this polymer layer after the thermal lamination by reacting reactive groups of the base polymer of the polymer layer with each other by at least 5 ° C, preferably at least 20 ° C, higher than the glass transition temperature before the thermal lamination. In this case, not only is a reactive coupling of the layers to be laminated together. Rather, the molecular weight and thus the glass transition temperature are increased by crosslinking of the polymer within the layer and between the layers. This complicates delamination in addition, since, for example, the printing inks are irreversibly damaged, in particular in a manipulation attempt by the high delamination temperatures necessary and the document is thereby destroyed. Preferably, the lamination temperature when using such polymer materials less than 180 ° C, more preferably still less than 150 ° C. The choice of suitable reactive groups is readily possible for a person skilled in the art of polymer chemistry. Exemplary reactive groups are selected from the group consisting of -CN, -OCN, -NCO, -NC, -SH, -S _x, -Tos, -SCN, -NCS, -H, -epoxy (-CHOCH _2), - NH ₂ , -NN ⁺ , -NN-R, -OH, -COOH, -CHO, -COOR, -Hal (-F, -Cl, -Br, -I), -Me-Hal (Me = at least divalent metal , for example Mg), -Si (OR) ₃ , -SiHal ₃ , -CH = CH ₂ , and -COR ", where R" can be any reactive or non-reactive group, for example H, Hal, C ₁ -C ₂₀ alkyl, C ₃ -C ₂₀ aryl, C ₄ -C ₂₀ -ArAlkyl, each branched or linear, saturated or unsaturated, optionally substituted, or corresponding heterocycles having one or more identical or different heteroatoms N, O, or S. Other reactive groups are of course possible. These include the reaction partners of the Diels-Alder reaction or a metathesis.

The reactive groups may be attached directly to the base polymer or linked to the base polymer via a spacer group. Suitable spacer groups are all spacer groups known to the person skilled in the art of polymer chemistry. The spacer groups may also be oligomers or polymers which impart elasticity, whereby a risk of breakage of the security and / or value document is reduced. Such elasticity-promoting spacer groups are known to the person skilled in the art and therefore need not be further described here. By way of example only, spacer groups may be mentioned which are selected from the group comprising - (CH ₂ ) _n -, - (CH ₂ -CH ₂ -O) _n -, - (SiR ₂ -O) _n -, - (C ₆ H ₄ ) _n -, - (C ₆ H ₁₀ ) _n , -C ₁ -C _n -alkylene, -C ₃ -C _{(n + 3)} -arylene, -C ₄ -C _{(n + 4)} - ArAlkylen-, each branched or linear, saturated or unsaturated, optionally substituted, or corresponding heterocycles having one or more identical or different heteroatoms O, N, or S, where n = 1 to 20, preferably 1 to 10. With regard to further reactive groups or possibilities of modification, reference is made to the reference " Ullmann's Encyclopedia of Industrial Chemistry ", Wiley Verlag, electronic edition 2006 , referenced. The term "base polymer" in the context of the above statements designates a polymer structure which does not bear any groups reactive under the lamination conditions used. These may be homopolymers or copolymers. Compared to the polymers mentioned also modified polymers are included.

The present invention serves to produce security features in security and / or value documents. The security features may in particular be personalized and / or individualized features. This means that the print representation represents a personalized and / or individualized feature. The personalized feature may in particular be a passport photograph. In principle, a personalized feature can also include data of the person to whom the security and / or value document is assigned, for example the date of birth, the address or identification number in a company, as well as biometric data, such as a digitized record of fingerprints, or the size, eye color of the person or their affiliation to a health insurance company. In principle, an individualized feature may represent data pertaining to a particular item, such as a motor vehicle, or to a particular entity, such as a bank account or a security.

The personalized and / or individualized feature in turn is changed by the formation of the individual print pixels in the main pixels and satellite pixels as another security feature. That despite the change, the printed image can be seen with the naked eye, while it can be seen, given a corresponding optical magnification, that the individual printing pixels are formed as ensembles of main pixels and satellite pixels.

The particular grid structure according to the invention with main pixels and satellite pixels is preferably realized with a digital printing method (non-impact printing), more preferably with a drop-on-demand printing method, and most preferably with an ink-jet printing method. If an inkjet printing process is used, ensembles of main and satellite pixels can be set by simply adjusting the printing process be generated. In other cases, these ensembles are merely simulated. In principle, therefore, all printing methods can be used with which such ensembles can be simulated in a screened representation of the individual picture elements (pixels). This presupposes of course that the printing method used achieves a sufficient resolution in order to be able to produce the picture elements composed of main and satellite pixels in addition to a conventional image composed of picture elements in the form of a sufficiently high quality image. For this purpose, the following printing methods are also basically applicable: conventional printing methods, such as wet and dry offset and other planographic printing, gravure, high-pressure, but also electrophotographic or thermographic process. As a printing method digital printing methods, in addition to the ink-jet printing method, for example, xerographic methods, preferred because they are very flexible, in particular for the production of personalized and / or individualized pattern.

In a preferred embodiment of the invention, the pattern is formed with an ink jet print head on one of the surfaces, the pattern being subdivided into pixels, and at least a portion of these pixels consisting of main and satellite pixels in the sense of the invention. In a most preferred embodiment of the invention, each satellite pixel is relative to a respective main pixel to which it is assigned at a predetermined angle α to the direction in which the inkjet printhead and the surface are moved relative to each other (printing direction) on the surface generated. This means that the satellite pixels, when viewed from the surface after printing, are arranged in a specific orientation to the associated main pixels, for example in the "5 o'clock position" or in the "half-o'clock position".

Furthermore, it is particularly preferred that said angle α is not 0 ° or 180 °, relative to the printing direction. By maintaining these angles, the satellite pixels would lie on the connecting lines of main pixels which are successively printed in the process (scanning) of the print head and the print medium relative to each other. Such orientation would typically result in conventional ink jet printing, even though there are no particular devices to suppress satellite pixels, because the satellite drops are later due to their lower exit velocity from the print head exit ports than the main drop hit the print medium and impinge on the connecting line successively printed main pixels because of the now made offset in the process of the printhead next to the main pixel. Depending on the printing direction, a satellite drop might appear to the right or left of the main pixel. In any case, the satellite pixel would always appear behind the main pixel, taking into account the direction of travel of the printhead. By maintaining the condition α ≠ 0 ° and α ≠ 180 °, the satellite pixels are not printed on the connecting lines, but above or below the connecting lines. Such an orientation can only be established if specific measures have been taken to specifically divert the satellite drops at an angle β with respect to a plane defined by the respective main pixel and the printing direction. Thus, it is precisely with such a condition of satellite drop generation that it is readily apparent that the satellite pixels have been selectively generated. In particular, each satellite pixel, irrespective of the printing direction relative to the respective main pixel to which it is associated, may be formed at a predetermined angle α to a connecting line of adjacent printed major pixels on the surface.

This is realized by appropriate adjustment of the print head and / or its adjustment. For this purpose, a device for deflecting the satellite drops emerging from the print head is provided on the print head. By their adjustment and / or suitable training this distraction can be effected. This device may, in particular, be a through-opening device, which is arranged directly adjacent to the outlet openings of the print head. By adjusting and / or appropriately shaping the device for deflecting the satellite ink droplets, the portion of the intervening liquid which ultimately forms the satellite pixels passes at an angle β to a plane passing through the respective main pixel and the printing direction is defined, off. This part of the ink liquid is formed by the tail of the ejected ink liquid whose airspeed is lower than the part of the ink liquid at the head of the ejected liquid stream and forming during the flight to the main droplet.

The device for deflecting the satellite drops can, as in US 7,093,915 B2 or US 2003/0179258 A1 formed by a through-hole plate, which is brought into direct contact with the part of the print head in contact, in the the outlet openings for the ink liquid are located. The passage openings in this plate are inserted in register with the outlet openings in the printhead in the plate. However, the plate is not mounted on the print head so that the outlet openings are aligned with the through holes, but such that there is a small offset, so that although there is a free cross section for the passage of the ink liquid, but this cross-section is narrowed. By moving the plate one-sided relative to the printhead, the tail of the fluid path receives a pulse parallel to the plane of the plate so that the satellite drop forming from the tail is deflected from the original exit direction in which the bulk of the ink fluid is expelled. become. The main drop maintains the exit direction defined by the normal to the plane defined by the exit ports of the printhead. In an alternative embodiment of the deflection plate, the passage openings in the plate are indeed adjusted in register with the outlet openings in the print head. However, in this embodiment, these through-holes are designed in a special way, in such a way that the trajectory of the satellite drop is deflected, for instance through through-holes with a curved, S-shaped or otherwise specially designed profile. With regard to the design of the print head with the plate is based on the aforementioned documents US 7,093,915 B2 and US 2003/0179258 A1 Referenced.

In a further preferred embodiment of the present invention, a predetermined color α at which a satellite pixel is generated relative to the main pixel to which it is associated is assigned a particular color. The main pixel and the associated satellite pixel are generated according to this embodiment at this angle α and printed in this color associated with the angle α . Thus, another security feature is available. This security feature is that a particular color is associated with a particular orientation of a satellite pixel relative to the main pixel to which it is associated, and that the main and satellite pixels are also printed in that color. A forgery or falsification occurs when such a shaped printing pixel is not printed in the associated color.

In a further development of this embodiment of the invention, a plurality of predefined angles α ₁ , α ₂ ,..., Α _n ,... Below which satellite pixels are generated relative to the respective main pixels to which they are associated are each assigned a specific color be. In this case, the main pixel and the associated satellite pixels are generated under the respective angles α _n and printed in this angle α _n associated color.

For example, a pattern may include printing pixels that appear at the 1 o'clock position, 4 o'clock position, 7 o'clock position, and 10 o'clock position on the printed surface, relative to the associated main pixels , The respective orientations are assigned specific colors, such as the colors of the CMYK color space, for example the 1 o'clock position of the color yellow, the 4 o'clock position of the color magenta, the 7 o'clock position of the color cyan and the 10 o'clock. Clock position of the color "Black". If then in a document a representation is included, which consists of pixels, each consisting of main and satellite pixels, wherein at least individual pixels are printed in a color that does not correspond to the respective associated orientation of the satellite pixels to their associated main pixels, so for example Printing pixel with satellite pixels in 7 o'clock position in yellow, the document proves to be fake or as falsified.

In a preferred embodiment of the invention, a plurality of predetermined angles α ₁ , α ₂ ,..., Α _n ,..., Below which satellite pixels are generated relative to the respective main pixels to which they are associated, each have a specific surface in the Be assigned layer composite. The main pixels and the associated satellite pixels are generated in this case at the respective angle α _n and on this surface associated with the angle α _n .

For example, a pattern on several, for example, four surfaces, distributed, which are superimposed after joining the individual polymer layers of the composite layer on which the surfaces are located and therefore give the representation. The print pixels are printed on each surface with a different orientation of the satellite pixels to the associated main pixels, for example on the first surface with satellite pixels in the 2 o'clock position, on the second surface in the 5 o'clock position, on the third surface in 8 o'clock position and on the fourth surface in 11 o'clock position. If it turns out that in a document with such coding of the pixels with colors an incorrect assignment takes place, it can be determined that this document is forged or falsified. This embodiment is particularly advantageous when the different surfaces are spaced from each other by at least one layer of the composite, so that a distinction of the individual composite layers is made possible.

In a further preferred embodiment of the invention, the representations in the above embodiment may be printed on the different surfaces in different colors. For example, multiple representations printed on different surfaces may be color separations of a color image. In this case, the individual color separations according to the above embodiments of the invention can be provided with different orientations of the satellite pixels and color-coded.

Thus, the said security features may in principle be formed on a single surface of a layer of the composite layer, or it may be formed on different surfaces in the multilayer composite layers, these multiple surfaces are preferably separated from each other by at least one polymer layer and thus spaced from each other, and wherein the layers of the layer composite are joined together such that the representations of all printed layers, for example color separations of a photo, preferably lie exactly above one another on the different surfaces. In this case, it is preferable to use polymer layers which are colorless and transparent in order to be able to visually visually recognize the printed layers in the different layers of the layer composite from the outside.

For example, a suitable representation, for example a passport picture, can be produced with satellite pixels in a predefined orientation of the satellite pixels to the associated main pixels, for example by dividing the representation into checkerboard-like fields and distributing the fields onto the different surfaces of the layer network in such a way that the fields alternating on successive surfaces. For example, a division of the fields on two surfaces can be made such that the first, third, fifth ... field of successive in a row Fields in the representation on a first surface and the second, fourth, sixth, ... field on a second surface and the corresponding fields of further rows, for example offset from the adjacent rows, are distributed in the same way to the two surfaces. Since the different surfaces on which the partial images are located are spaced from one another, the result is a spatial impression of the representation, which is the more the more printed layers on different surfaces in the laminate are included in this representation. Furthermore, it is also possible to produce different color separations of the representation and to print the color separations on different surfaces in the layer composite so that the desired colored representation results when the individual polymer layers are combined to form the layer composite.

In a further preferred embodiment of the invention, a further printing layer can also be applied, this further printing layer being printed on a surface which is modified in partial regions, for example with a screen or other type of pattern. Screening or other patterning in the modification of the surface is performed in this embodiment by changing the surface energy of the surface to be screened in partial areas corresponding to the grid, so that the ink liquid does not wet the surface in these partial areas. This change in surface energy may consist in hydrophilizing an otherwise hydrophobic surface or in hydrophobing an otherwise hydrophilic surface. Applications for such surface changes are, for example, in WO 03056641 A1 and in " Microcontact Printing of Self-Assembled Monolayers ", Surface Science, The Whitesides Research Group, which is available at http://gmwgroup.harvard.edu/research_surfacescience.html, on Feb. 8, 2008 retrieved, described. After halftoning, a visible image is printed on the surface in the print area where the surface is partially modified. Thus, a primary visible image is created and, in addition, a secondary latent visible image in the same print area. The printed image of the primary visible pressure is superimposed by the pattern of the surface sub-areas modified with respect to their surface energy: where the modified surface areas are, the material of the layer composite decreases no printing ink on. Thus, for example, of circular grid surfaces which are produced by an inkjet printing process, for example, laterally cut off areas, or these areas are completely eliminated if they hit the modified sections during the printing process. For pressure ink impinging on these subregions is rejected by these subregions due to the changed surface energy and flows off into adjacent subregions of the surface in which the surface energy has not changed and on which the printing ink adheres.

In the event that the polymer layers are not wettable with water and the ink composition is substantially immiscible with water, for example, if the polymer layer is polycarbonate, the portions of the surfaces in the printing areas may be modified by increasing their hydrophilicity, i. their tendency is increased to be wetted by water. This ensures that the ink is not absorbed during the printing process of the modified areas but rejected. Hydrophilization can be carried out, for example, by using reactive reagents on the surfaces in the subregions to be modified.

For example, the surface can be provided with a raster-shaped printing with a raster reproducing this silicone stamp in microcontact printing process. Alternatively, an aerosol writing method can also be used, for example the M ³ D® method from Optomec®, US. This is a maskless application method in which the reactive reagents are atomized with a sprayer, the generated aerosol is transported with a first gas stream to a nozzle and sprayed by means of a second gas stream focused on the surface sub-areas.

For pressure, the surface may be contacted with the reactive reagents which react with and hydrophilize the material of the surface. Such hydrophilic reagents may, in particular, be compounds which have at least one group reactive with the material of the polymer layers to be modified and at least one hydrophilic group. Spacer groups may be provided between the reactive groups and the hydrophilic groups. The reactive groups may, inter alia, be selected from the group comprising carboxylic acid chloride, carboxylic acid anhydride, Oxirane and phthalimide groups. Such reagents are particularly useful in modifying surfaces of polycarbonate polymer layers containing -O- (C = O) -O- groups to which these reactive groups can bind by nucleophilic substitution so that the hydrophilic reagents become chemically bound , From this it can be seen that, in principle, other nucleophilic reagents can be used which can enter into a suitable chemical bond with the polycarbonate. For chemical bonding of the hydrophilic reagents to the surface subregions suitable reaction conditions must be observed. These are known to those skilled in the art of organic synthesis so that they can select the appropriate conditions. Alternatively, the portions of the surface to be modified may be provided with a hydrophilic coating, such as a hydrophilic paste or a hydrophilic dispersion. To impart adhesion of the paste or dispersion to the hydrophobic surface, the paste or dispersion contains, for example, a surfactant.

In contrast, hydrophilic surfaces are rendered hydrophobic, for example by fluorination or siliconization, for example by applying a hydrophobic layer, for example a layer containing fluorinated binder components. The structuring to produce the hydrophobic subregions can in turn be realized with a stamp in the microcontact printing process or with a drop-on-demand printing process or with a photolithographic process. Polycarbonate layers can also be rendered hydrophobic.

For example, with this embodiment, diamond-shaped, triangular, square or hexagonal or also differently sized printing pixels can be produced. Of course, the different in terms of shape and / or size printing pixels resulting from this screening, in turn, a color can be assigned, for example, triangular pressure pixels of cyan, squared pressure pixels of the color magenta, hexagonal pressure pixels of the color yellow and diamond-shaped printing pixels of the color black , Alternatively, instead of screening, any other pattern may be created as a secondary latent visible image superimposing the primary visible image, such as guilloches.

In one embodiment, the security feature formed by the primary visible image and the secondary latent visible pattern may be generated in a print area other than the print area in which the security feature of the invention formed by print pixels with satellite pixels is created becomes. In this case, the two pressure areas may preferably be on surfaces in the layer composite, which are separated from each other by at least one layer of the composite. In addition, these two pressure ranges can overlap at least partially, so that overlapping partial images result in a common representation, for example a passport photograph. In the individual partial images, different security features are realized in this case: first, in a first printing area, the security feature formed by additional satellite pixels at the associated main pixels, and in a second printing area, the security feature realized by the modification of the partial areas of the surfaces.

In another embodiment variant, the generation of security features according to the invention by generating satellite pixels in addition to main pixels can also be combined with the above further embodiment, in which the surface is modified in subregions, in the same printing area and thus on the same surface of a polymer layer. If, in this case, the primary visible print image is to be printed with satellites, then it is advantageous if the secondary latent visible information results in surface screening with grid areas that are larger than the areas of the print pixels. In this case, the satellites are visible at the main pixels because the print pixels in the grid areas are substantially completely contained. Thus, the presence of both the rasterization and the formation of the print pixels with main and satellite pixels represents further security features.

The above embodiments may also refer to a black / white representation, optionally with gray tones, instead of colored representations. These embodiments represent additional security features to the security features according to the invention and can be combined with these.

Furthermore, it is advantageous if the respective printed layers are arranged in the polymer layer composite on inner layers of the composite. In this case is prevents or even precludes forgery or falsification of printed layers serving as security features.

However, in this case there is the further problem mentioned above that conventional card-shaped data carriers can be delaminated relatively easily by manipulation. The problem of delamination in the case where a security feature is applied to an inner layer of the laminar structure by means of printing technology can be solved by the fact that the printing layers contain binders which at least substantially consist of the same polymer as the material of the layers of the laminar composite , In this case, the risk of delaminations is virtually eliminated because laminating forms a monolithic composite of the individual layers. It is particularly preferred if the printing layers comprise polycarbonate-based binders if at least some of the layers of the composite also consist of polycarbonate. In the latter case, the print layers are printed on inner layers of the laminate, in particular all layers of the laminate which adjoin the print layers are formed from polycarbonate.

• worin R¹ und R² unabhängig voneinander Wasserstoff, Halogen, bevorzugt Chlor oder Brom, C₁-C₈-Alkyl, C₅-C₆-Cycloalkyl, C₆-C₁₀-Aryl, bevorzugt Phenyl, und C₇-C₁₂-Aralkyl, bevorzugt Phenyl-C₁-C₄-Alkyl, insbesondere Benzyl, sind;
• m eine ganze Zahl von 4 bis 7, bevorzugt 4 oder 5 ist; R³ und R⁴ für jedes X individuell wählbar, unabhängig voneinander Wasserstoff oder C₁-C₆-Alkyl ist; X Kohlenstoff und n eine ganze Zahl größer 20 bedeuten, mit der Maßgabe, dass an mindestens einem Atom X, R³ und R⁴ gleichzeitig Alkyl bedeuten. Bevorzugt ist es, wenn an 1 bis 2 Atomen X, insbesondere nur an einem Atom X, R³ und R⁴ gleichzeitig Alkyl sind. R³ und R⁴ können insbesondere Methyl sein. Die X-Atome in α-Stellung zu dem Diphenyl-substituierten C-Atom (C1) können nicht dialkylsubstituiert sein. Die X-Atome in β-Stellung zu C1 können mit Alkyl disubstituiert sein. Bevorzugt ist m = 4 oder 5. Das Polycarbonatderivat kann beispielsweise auf Basis von Monomeren, wie 4,4'-(3,3,5-Trimethylcyclohexan-1,1-diyl)diphenol, 4,4'-(3,3-Dimethylcyclohexan-1,1-diyl)diphenol, oder 4,4'-(2,4,4-Trimethylcyclopentan-1,1-diyl)diphenol, gebildet sein. Ein solches Polycarbonatderivat kann beispielsweise gemäß der Literaturstelle DE-A 38 32 396 aus Diphenolen der Formel (Ia) hergestellt werden. Es können sowohl ein Diphenol der Formel (Ia) unter Bildung von Homopolycarbonaten als auch mehrere Diphenole der Formel (Ia) unter Bildung von Copolycarbonaten verwendet werden (Bedeutung von Resten, Gruppen und Parametern, wie in Formel I).
  

For the printing on polycarbonate composite layers basically all customary inks can be used. Preference is given to the use of a preparation comprising: A) 0.1 to 20 wt .-% of a binder with a polycarbonate derivative, B) 30 to 99.9 wt .-% of a preferably organic solvent or solvent mixture, C) 0 to 10 wt D) 0 to 10% by weight of a functional material or a mixture of functional materials, E) 0 to 30% by weight of additives and / or auxiliaries , or a mixture of such substances, wherein the sum of the components A) to E) always gives 100 wt .-%, as a printing ink. Such polycarbonate derivatives are highly compatible with polycarbonate materials, in particular with polycarbonates based on bisphenol A, such as, for example, Makrofol® films. In addition, the polycarbonate derivative used is stable to high temperatures and shows no discoloration at lamination typical temperatures up to 200 ° C and more, whereby the use of the above-described low-T _g materials is not necessary. In particular, the polycarbonate derivative may contain functional carbonate structural units of the formula (I)

• wherein R ¹ and R ² independently of one another are hydrogen, halogen, preferably chlorine or bromine, C ₁ -C ₈ -alkyl, C ₅ -C ₆ -cycloalkyl, C ₆ -C ₁₀ -aryl, preferably phenyl, and C ₇ -C ₁₂ -Aralkyl, preferably phenyl-C ₁ -C ₄ alkyl, in particular benzyl, are;
• m is an integer from 4 to 7, preferably 4 or 5; R ³ and R ^{4 are} individually selectable for each X, independently of one another is hydrogen or C ₁ -C ₆ alkyl; X is carbon and n is an integer greater than 20, with the proviso that on at least one atom X, R ³ and R ^{4 are} simultaneously alkyl. It is preferred for X, R ³ and R ^{4 to be} simultaneously alkyl at 1 to 2 atoms, in particular only at one atom. R ³ and R ⁴ may be in particular methyl. The X atoms in the α position to the diphenyl-substituted C atom (C1) may not be dialkyl-substituted. The X atoms in the β- position to C1 may be disubstituted with alkyl. Preferably m = 4 or 5. The polycarbonate derivative can be prepared, for example, based on monomers such as 4,4 '- (3,3,5-trimethylcyclohexane-1,1-diyl) diphenol, 4,4' - (3,3-) Dimethylcyclohexane-1,1-diyl) diphenol, or 4,4 '- (2,4,4-trimethylcyclopentane-1,1-diyl) diphenol. Such a polycarbonate derivative can be used, for example, according to the literature DE-A 38 32 396 be prepared from diphenols of the formula (Ia). It is possible to use both a diphenol of the formula (Ia) to form homopolycarbonates and a plurality of diphenols of the formula (Ia) to form copolycarbonates (meaning of radicals, groups and parameters, as in formula I).
  

In addition, the diphenols of the formula (Ia) may also be mixed with other diphenols, for example with those of the formula (Ib)

HO-Z-OH (Ib),

be used for the preparation of high molecular weight, thermoplastic, aromatic polycarbonate derivatives.

worin R einen verzweigten C₈- und/oder C₉-Alkylrest darstellt. Bevorzugt ist im Alkylrest R der Anteil an CH₃-Protonen zwischen 47 und 89 % und der Anteil der CH- und CH₂-Protonen zwischen 53 und 11 %; ebenfalls bevorzugt ist R in o- und/oder p-Stellung zur OH-Gruppe, und besonders bevorzugt die obere Grenze des ortho-Anteils 20 %. Die Kettenabbrecher werden im allgemeinen in Mengen von 0,5 bis 10, bevorzugt 1,5 bis 8 Mol-%, bezogen auf eingesetzte Diphenole, eingesetzt. Die Polycarbonatderivate können vorzugsweise nach dem Phasengrenzflächenverhalten (vgl. H.Schnell in: Chemistry and Physics of Polycarbonates, Polymer Reviews, Vol. IX, Seite 33ff., Interscience Publ. 1964 ) in an sich bekannter Weise hergestellt werden. Hierbei werden die Diphenole der Formel (Ia) in wässrig alkalischer Phase gelöst. Zur Herstellung von Copolycarbonaten mit anderen Diphenolen werden Gemische von Diphenolen der Formel (Ia) und den anderen Diphenolen, beispielsweise denen der Formel (Ib), eingesetzt. Zur Regulierung des Molekulargewichts können Kettenabbrecher z.B. der Formel (Ic) zugegeben werden. Dann wird in Gegenwart einer inerten, vorzugsweise Polycarbonat lösenden, organischen Phase mit Phosgen nach der Methode der Phasengrenzflächenkondensation umgesetzt. Die Reaktionstemperatur liegt im Bereich von 0°C bis 40°C. Die gegebenenfalls mit verwendeten Verzweiger (bevorzugt 0,05 bis 2,0 Mol-%) können entweder mit den Diphenolen in der wässrig alkalischen Phase vorgelegt werden oder in dem organischen Lösungsmittel gelöst vor Phosgenierung zugegeben werden. Neben den Diphenolen der Formel (Ia) und gegebenenfalls anderen Diphenolen (Ib) können auch deren Mono- und/oder Bis-chlorkohlensäureester mit verwendet werden, wobei diese in organischen Lösungsmitteln gelöst zugegeben werden. Die Menge an Kettenabbrechern sowie an Verzweigern richtet sich dann nach der molaren Menge von Diphenolat-Resten entsprechend Formel (Ia) und gegebenenfalls Formel (Ib); bei Mitverwendung von Chlorkohlensäureestern kann die Phosgenmenge in bekannter Weise entsprechend reduziert werden. Geeignete organische Lösungsmittel für die Kettenabbrecher sowie gegebenenfalls für die Verzweiger und die Chlorkohlensäureester sind beispielsweise Methylenchlorid, Chlorbenzol sowie insbesondere Mischungen aus Methylenchlorid und Chlorbenzol. Gegebenenfalls können die verwendeten Kettenabbrecher und Verzweiger im gleichen Solvens gelöst werden. Als organische Phase für die Phasengrenzflächenpolykondensation dienen beispielsweise Methylenchlorid, Chlorbenzol sowie Mischungen aus Methylenchlorid und Chlorbenzol. Als wässrige alkalische Phase dient beispielsweise NaOH-Lösung. Die Herstellung der Polycarbonatderivate nach dem Phasengrenzflächenverfahren kann in üblicher Weise durch Katalysatoren, wie tertiäre Amine, insbesondere tertiäre aliphatische Amine, wie Tributylamin oder Triethylamin, katalysiert werden; die Katalysatoren können in Mengen von 0,05 bis 10 Mol-%, bezogen auf Mole an eingesetzten Diphenolen, eingesetzt werden. Die Katalysatoren können vor Beginn der Phosgenierung oder während oder auch nach der Phosgenierung zugesetzt werden. Die Polycarbonatderivate können nach dem bekannten Verfahren in homogener Phase, dem sogenannten "Pyridinverfahren" sowie nach dem bekannten Schmelzeumesterungsverfahren unter Verwendung von beispielsweise Diphenylcarbonat anstelle von Phosgen hergestellt werden. Die Polycarbonatderivate können linear oder verzweigt sein, sie sind Homopolycarbonate oder Copolycarbonate auf Basis der Diphenole der Formel (Ia). Durch die beliebige Komposition mit anderen Diphenolen, insbesondere mit denen der Formel (Ib) lassen sich die Polycarbonateigenschaften in günstiger Weise variieren. In solchen Copolycarbonaten sind die Diphenole der Formel (Ia) in Mengen von 100 Mol-% bis 2 Mol-%, vorzugsweise in Mengen von 100 Mol-% bis 10 Mol-% und insbesondere in Mengen von 100 Mol-% bis 30 Mol-%, bezogen auf die Gesamtmenge von 100 Mol-% an Diphenoleinheiten, in Polycarbonatderivaten enthalten. Das Polycarbonatderivat kann ein Copolymer sein, enthaltend, insbesondere hieraus bestehend, Monomereinheiten M1 auf Basis der Formel (Ib),vorzugsweise Bisphenol A, sowie Monomereinheiten M2 auf Basis des geminal disubstituierten Dihydroxydiphenylcycloalkans, vorzugsweise des 4,4'-(3,3,5-trimethylcyclohexan-1,1-diyl)diphenols, wobei das Molverhältnis M2/M1 vorzugsweise größer als 0,3, insbesondere größer als 0,4, beispielsweise größer als 0,5 ist. Bevorzugt ist es, wenn das Polycarbonatderivat ein mittleres Molekulargewicht (Gewichtsmittel) von mindestens 10.000, vorzugsweise von 20.000 bis 300.000, aufweist.Suitable other diphenols of the formula (Ib) are those in which Z is an aromatic radical having 6 to 30 C atoms, which may contain one or more aromatic nuclei, may be substituted, and aliphatic radicals or cycloaliphatic radicals other than those of the formula (II) Ia) or heteroatoms may contain as bridge members. Examples of the diphenols of the formula (Ib) are hydroquinone, resorcinol, dihydroxydiphenyls, bis (hydroxyphenyl) alkanes, bis (hydroxyphenyl) cycloalkanes, bis (hydroxyphenyl) sulfides, bis (hydroxyphenyl) ether, bis ( hydroxyphenyl) ketones, bis (hydroxyphenyl) sulfones, bis (hydroxyphenyl) sulfoxides, α , α 'bis (hydroxyphenyl) diisopropylbenzenes and their nuclear alkylated and nuclear halogenated compounds. These and other suitable diphenols are, for example, in US-A 3,028,365 . US-A 2,999,835 . US-A 3,148,172 . US-A 3,275,601 . US-A 2,991,273 . US-A 3,271,367 . US-A 3,062,781 . US-A 2,970,131 . US-A 2,999,846 . DE-A 1 570 703 . DE-A 2 063 050 . DE-A 2 063 052 . DE-A 2 211 956 . FR-A 1 561 518 and in H. Schnell in: Chemistry and Physics of Polycarbonates, Interscience Publishers, New York 1964 , described. Preferred other diphenols are, for example: 4,4'-dihydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) propane, 2,4-bis (4-hydroxyphenyl) -2-methylbutane, 1,1-bis ( 4-hydroxyphenyl) cyclohexane, α , α- bis (4-hydroxyphenyl) -p-diisopropylbenzene, 2,2-bis- (3-methyl-4-hydroxyphenyl) -propane, 2,2-bis (3-chloro-4-hydroxyphenyl) -propane, bis (3,5-dimethyl-4-hydroxyphenyl) - methane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, bis (3,5-dimethyl-4-hydroxyphenyl) sulfone, 2,4-bis (3,5-dimethyl 4-hydroxyphenyl) -2-methylbutane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) cyclohexane, α , α- bis (3,5-dimethyl-4-hydroxyphenyl) -p- diisopropylbenzene, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) -propane and 2,2-bis (3,5-dibromo-4-hydroxyphenyl) -propane. Particularly preferred diphenols of the formula (Ib) are, for example, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) -propane and 1,1-bis (4-hydroxyphenyl) -cyclohexane. In particular, 2,2-bis (4-hydroxyphenyl) propane is preferred. The other diphenols can be used both individually and in a mixture. The molar ratio of diphenols of the formula (Ia) to the other diphenols of the formula (Ib) which may optionally be used should be between 100 mol% (Ia) to 0 mol% (Ib) and 2 mol% (Ia) 98 mol% (Ib), preferably between 100 mol% (Ia) to 0 mol% (Ib) and 10 mol% (Ia) to 90 mol% (Ib) and in particular between 100 mol% (Ia ) to 0 mol% (Ib) and 30 mol% (Ia) to 70 mol% (Ib). The high molecular weight polycarbonate derivatives from the diphenols of the formula (Ia), optionally in combination with other diphenols, can be prepared by the known polycarbonate production processes. The various diphenols can be linked together both statistically and in blocks. The polycarbonate derivatives used can be branched in a manner known per se. If the branching is desired, this can in known manner by condensing small amounts, preferably amounts of 0.05 to 2.0 mol% (based on diphenols), of trifunctional or more than trifunctional compounds, especially those with three or more than three phenolic hydroxyl groups. Some branching agents having three or more than three phenolic hydroxyl groups are phloroglucinol, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene-2,4,6-dimethyl-2,4,6-tri - (4-hydroxyphenyl) heptane, 1,3,5-tri (4-hydroxyphenyl) benzene, 1,1,1-tri- (4-hydroxyphenyl) -ethane, tri- (4-hydroxyphenyl) -phenylmethane , 2,2-bis [4,4-bis (4-hydroxyphenyl) cyclohexyl] propane, 2,4-bis (4-hydroxyphenyl-isopropyl) -phenol, 2,6-bis (2-bis) hydroxy-5-methylbenzyl) -4-methylphenol, 2- (4-hydroxyphenyl) -2- (2,4-dihydroxyphenyl) -propane, hexa- [4- (4-hydroxyphenyl-isopropyl) -phenyl] -ortho terephthalic acid ester, tetra (4-hydroxyphenyl) methane, tetra- [4- (4-hydroxyphenyl-isopropyl) -phenoxy] -methane and 1,4-bis- [4 ', 4 "-dihydroxytriphenyl) -methyl] -benzene Some of the other trifunctional compounds are 2,4-dihydroxybenzoic acid, trimesic acid, Cyanuric chloride and 3,3-bis (3-methyl-4-hydroxyphenyl) -2-oxo-2,3-dihydroindole. As chain terminators known per se regulation of the molecular weight of the polycarbonate derivatives are monofunctional compounds in conventional concentrates. Suitable compounds are, for example, phenol, tert-butylphenols or other alkyl-substituted phenols. For controlling the molecular weight, in particular small amounts of phenols of the formula (Ic) are suitable

wherein R represents a branched C ₈ and / or C ₉ alkyl radical. Preferably, in the alkyl radical R, the proportion of CH ₃ protons between 47 and 89% and the proportion of CH and CH ₂ protons between 53 and 11%; also preferably R is in the o- and / or p-position to the OH group, and more preferably the upper limit of the ortho-portion is 20%. The chain terminators are generally used in amounts of 0.5 to 10, preferably 1.5 to 8 mol%, based on diphenols used. The polycarbonate derivatives may preferably be prepared according to the interfacial behavior (cf. H. Schnell, Chemistry and Physics of Polycarbonates, Polymer Reviews, Vol. IX, p. 33ff., Interscience Publ. 1964 ) are prepared in a conventional manner. In this case, the diphenols of the formula (Ia) are dissolved in an aqueous alkaline phase. For the preparation of copolycarbonates with other diphenols, mixtures of diphenols of the formula (Ia) and the other diphenols, for example those of the formula (Ib), are used. To regulate the molecular weight, chain terminators of, for example, the formula (Ic) can be added. Then, in the presence of an inert, preferably polycarbonate-dissolving, organic phase is reacted with phosgene by the method of interfacial condensation. The reaction temperature is in the range of 0 ° C to 40 ° C. The optionally used with branching agents (preferably 0.05 to 2.0 mol%) can be presented either with the diphenols in the aqueous alkaline phase or dissolved in the organic solvent added before phosgenation. In addition to the diphenols of the formula (Ia) and, if appropriate, other diphenols (Ib), their mono- and / or bis-chloroformates may also be used, these being dissolved in organic solvents be added. The amount of chain terminators and of branching agents then depends on the molar amount of diphenolate radicals corresponding to formula (Ia) and optionally formula (Ib); When using chloroformates the amount of phosgene can be reduced accordingly in a known manner. Suitable organic solvents for the chain terminators and optionally for the branching agents and the chloroformates are, for example, methylene chloride, chlorobenzene and in particular mixtures of methylene chloride and chlorobenzene. Optionally, the chain terminators and branching agents used can be dissolved in the same solvent. For example, methylene chloride, chlorobenzene and mixtures of methylene chloride and chlorobenzene serve as the organic phase for the interfacial polycondensation. The aqueous alkaline phase used is, for example, NaOH solution. The preparation of the polycarbonate derivatives by the interfacial process can be catalyzed in a conventional manner by catalysts such as tertiary amines, in particular tertiary aliphatic amines such as tributylamine or triethylamine; the catalysts can be used in amounts of 0.05 to 10 mol%, based on moles of diphenols used. The catalysts can be added before the beginning of the phosgenation or during or after the phosgenation. The polycarbonate derivatives can be prepared by the known method in the homogeneous phase, the so-called "pyridine process" and by the known melt transesterification process using, for example, diphenyl carbonate instead of phosgene. The polycarbonate derivatives may be linear or branched, they are homopolycarbonates or copolycarbonates based on the diphenols of the formula (Ia). By arbitrary composition with other diphenols, in particular with those of the formula (Ib), the polycarbonate properties can be varied in a favorable manner. In such copolycarbonates, the diphenols of the formula (Ia) are present in amounts of from 100 mol% to 2 mol%, preferably in amounts of from 100 mol% to 10 mol% and in particular in amounts of from 100 mol% to 30 mol% %, based on the total amount of 100 mol% of diphenol units contained in polycarbonate derivatives. The polycarbonate derivative may be a copolymer comprising, in particular consisting thereof, monomer units M1 based on the formula (Ib), preferably bisphenol A, and monomer units M2 based on the geminally disubstituted dihydroxydiphenylcycloalkane, preferably the 4,4 '- (3,3,5 -trimethylcyclohexane-1,1-diyl) diphenol, wherein the molar ratio M2 / M1 is preferably greater than 0.3, in particular greater than 0.4, for example greater than 0.5. It is preferred if the polycarbonate derivative has an average molecular weight (Weight average) of at least 10,000, preferably from 20,000 to 300,000.

In principle, component B may be substantially organic or aqueous. Substantially aqueous means that up to 20% by weight of component B) can be organic solvents. Substantially organic means that up to 5% by weight of water may be present in component B). Component B preferably contains one or consists of a liquid aliphatic, cycloaliphatic and / or aromatic hydrocarbon, a liquid organic ester and / or a mixture of such substances. The organic solvents used are preferably halogen-free organic solvents. Particularly suitable are aliphatic, cycloaliphatic, aromatic hydrocarbons, such as mesitylene, 1,2,4-trimethylbenzene, cumene and solvent naphtha, toluene, xylene, (organic) esters, such as methyl acetate, ethyl acetate, butyl acetate, methoxypropyl acetate, ethyl 3-ethoxypropionate , Preference is given to mesitylene, 1,2,4-trimethylbenzene, cumene and solvent naphtha, toluene, xylene, methyl acetate, ethyl acetate, methoxypropyl acetate. Ethyl 3-ethoxypropionate. Very particular preference is given to mesitylene (1,3,5-trimethylbenzene), 1,2,4-trimethylbenzene, cumene (2-phenylpropane), solvent naphtha and ethyl 3-ethoxypropionate. A suitable solvent mixture comprises, for example, L1) 0 to 10% by weight, preferably 1 to 5% by weight, in particular 2 to 3% by weight, mesitylene, L2) 10 to 50% by weight, preferably 25 to 50% by weight %, in particular 30 to 40% by weight, 1-methoxy-2-propanol acetate, L3) 0 to 20% by weight, preferably 1 to 20% by weight, in particular 7 to 15% by weight, 1 , 2,4-trimethylbenzene, L4) 10 to 50 wt.%, Preferably 25 to 50 wt.%, In particular 30 to 40 wt.%, Ethyl 3-ethoxypropionate, L5) 0 to 10 wt. , preferably 0.01 to 2 wt .-%, in particular 0.05 to 0.5 wt .-%, cumene, and L6) 0 to 80 wt .-%, preferably 1 to 40 wt .-%, in particular 15 to 25 wt .-%, solvent naphtha, wherein the sum of components L1 to L6 always gives 100 wt .-%.

The preparation may contain in detail: A) 0.1 to 10 wt .-%, in particular 0.5 to 5 wt .-%, of a binder with a polycarbonate derivative based on a geminal disubstituted dihydroxydiphenylcycloalkane, B) 40 to 99.9 wt %, in particular 45 to 99.5% by weight, of an organic solvent or solvent mixture, C) 0.1 to 6% by weight, in particular 0.5 to 4% by weight, of a colorant or colorant mixture, D ) 0.001 to 6 wt .-%, in particular 0.1 to 4 wt .-%, of a functional material or a Mixture of functional materials, E) 0.1 to 30 wt .-%, in particular 1 to 20 wt .-%, additives and / or auxiliaries, or a mixture of such substances.

As component C, if a colorant is to be provided, basically any colorant or colorant mixture comes into question. Colorants are all colorants. That means it can be both colorant (a review of dyes there Ullmann's Encyclopedia of Industrial Chemistry, Electronic Release 2007, Wiley Publishing, Chapter "Dyes, General Survey ") as well as pigments (gives an overview of organic and inorganic pigments Ullmann's Encyclopedia of Industrial Chemistry, Electronic Release 2007, Wiley Verlag, chapter "Pigments, Organic Dyes should be soluble or (stably) dispersible or suspendible in the solvents of component B. Furthermore, it is advantageous if the colorant is heated at temperatures of 160 ° C and more for a period of time It is also possible for the colorant to undergo a predetermined and reproducible color change under the processing conditions and to be selected accordingly .Pigments must be present not only in temperature stability, but also in the finest particle size distribution In practice, this means that the particle size should not exceed 1.0 μm, since otherwise blockages in the print head are the result.As a rule, nanoscale solid-state pigments and dissolved dyes have proved useful.The colorants can be cationic, anionic or even neutral. Only as examples of inkstr Colorants which can be used for printing are: Brilliant black CI No. 28440, Chromogen black CI No. 14645, Direct deep black E CI No. 30235, true black salt B CI No. 37245, true black salt K CI No. 37190, Sudan black HB CI 26150, naphthol black CI No. 20470, Bayscript® Liquid Black, CI Basic Black 11, CI Basic Blue 154, Cartasol® Turquoise K-ZL liquid, Cartasol® Turquoise K-RL liquid (CI Basic Blue 140), Cartasol Blue K5R liquid. Also suitable are, for example, the commercially available dyes Hostafine® Black TS liquid (sold by Clariant GmbH Germany), Bayscript® Black Liquid (CI mixture, marketed by Bayer AG Germany), Cartasol® Black MG liquid (CI Basic Black 11, Registered trademark of Clariant GmbH Germany), Flexonylblack® PR 100 (E CI No. 30235, marketed by Hoechst AG), Rhodamine B, Cartasol® Orange K3 GL, Cartasol® Yellow K4 GL, Cartasol® K GL, or Cartasol® Red K -3B. Furthermore, anthraquinone, azo, quinophthalone, coumarin, methine, perinone and / or pyrazole dyes can be used as soluble colorants. For example, under the brand name Macrolex® available, find use. Other suitable colorants are in the reference Ullmann's Encyclopedia of Industrial Chemistry, Electronic Release 2007, Wiley Publishing, Chapter "Colorants Used in Ink Jet Inks Well-soluble colorants lead to an optimal integration into the matrix or the binder of the print layer The colorants can be added either directly as a dye or pigment or as a paste, a mixture of dye and pigment together with another binder additional binder should be chemically compatible with the other components of the formulation, if such a paste is used as a colorant, the quantity of component B refers to the colorant without the other components of the paste, these other components of the paste are then included in component E. When using so-called colored pigments in the scale colors cyan-magenta-yellow and preferably also (soot) black solid color images are possible.

Component D comprises substances that can be seen directly by the human eye or by the use of suitable detectors using technical aids. Here are the materials known to those skilled in the art (see also van Renesse in: Optical document security, 3rd ed., Artech House, 2005 ), which are used to secure value and security documents. These include luminescent substances (dyes or pigments, organic or inorganic) such as photoluminophores, electroluminophores, Antistokes luminophores, fluorophores, but also magnetizable, photoacoustically addressable or piezoelectric materials. Furthermore, Raman-active or Raman-reinforcing materials can be used, as well as so-called barcode materials. Again, the preferred criteria are either the solubility in the component B or pigmented systems particle sizes <1 micron and a temperature stability for temperatures> 160 ° C in the sense of the comments on the component C. Functional materials can be added directly or via a paste, ie a mixture with a further binder, which then forms part of component E, or the binder of component A.

Component E in ink-jet inks comprises conventionally prepared materials such as anti-foaming agents, modifiers, wetting agents, surfactants, flow agents, dryers, catalysts, (light) stabilizers, preservatives, biocides, surfactants, organic Polymers for viscosity adjustment, and buffer systems. As adjusting agents are customary actuating salts in question. An example of this is sodium lactate. As biocides, all commercially available preservatives which are used for inks come into question. Examples are Proxel® GXL and Parmetol® A26. Suitable surfactants are all commercially available surfactants which are used for inks. Preferred are amphoteric or nonionic surfactants. Of course, it is also possible to use special anionic or cationic surfactants which do not alter the properties of the dye. Examples of suitable surfactants are betaines and ethoxylated diols. Examples are the product series Surfynol® and Tergitol®. The amount of surfactants is particularly selected when used for ink-jet printing, for example, provided that the surface tension of the ink is in the range of 10 to 60 mN / m, preferably 20 to 45 mN / m, measured at 25 ° C. A buffer system can be set up which stabilizes the pH in the range from 2.5 to 8.5, in particular in the range from 5 to 8. Suitable buffer systems are lithium acetate, borate buffer, triethanolamine or acetic acid / sodium acetate. A buffer system will be considered in particular in the case of a substantially aqueous component B. To adjust the viscosity of the ink (possibly water-soluble) polymers can be provided. Here all suitable for conventional ink formulations polymers come into question. Examples are water-soluble starch, in particular with an average molecular weight of 3,000 to 7,000, polyvinylpyrrolidone, in particular with an average molecular weight of 25,000 to 250,000, polyvinyl alcohol, in particular with an average molecular weight of 10,000 to 20,000, xanthan gum, carboxymethyl cellulose, ethylene oxide / propylene oxide Block copolymer, especially having an average molecular weight of 1,000 to 8,000. An example of the latter block copolymer is the product series Pluronic®. The proportion of biocide, based on the total amount of ink, may be in the range of 0 to 0.5% by weight, preferably 0.1 to 0.3% by weight. The proportion of surfactant, based on the total amount of ink, can range from 0 to 0.2 wt .-%. The proportion of adjusting agents, based on the total amount of ink, 0 to 1 wt .-%, preferably 0.1 to 0.5 wt .-%, amount. The auxiliaries also include other components, such as, for example, acetic acid, formic acid or n-methyl-pyrrolidone or other polymers from the dye solution or paste used. With respect to substances which are suitable as component E, is supplemented, for example, on Ullmann's Encyclopaedia of Chemical Industry, Electronic Release 2007, Wiley Publishing, Chapter "Paints and Coatings", Section "Paint Additives ", directed.

The above-described ink composition is particularly suitable for ink-jet printing, but may be used for any other printing technique as long as the ratio of the individual components to the application is adjusted. An advantage in this context is that the composition described contains a polycarbonate derivative as a binder, if the polymer layers of the composite also consist of polycarbonate.

Fig. 1

zeigt typische Hauptpixel-Satellitenpixel-Ensembles;

Fig. 2

zeigt verschiedene Varianten von Haupt- mit Satellitenpixeln;

Fig. 3

zeigt eine schematische Darstellung eines über ein Druckmedium verfahrenen Tintenstrahldruckkopfes und die dabei erzeugten Haupt- und Satelliten-Druckpixel;

Fig. 4

zeigt eine schematische Darstellung einer Düsenplatte an einem Tintenstrahldruckkopf im Querschnitt;

Fig. 5

zeigt eine schematische Darstellung von Druckpixeln, bestehend aus Haupt- und Satellitenpixeln;

Fig. 6

zeigt eine schematische Darstellung von Druckpixeln, bestehend aus Haupt- und Satellitenpixeln, die mit einem latent sichtbaren Bild aus einer rautenförmigen Rasterung überlagert sind (Fig. 6C).

In the following, the invention will be described by way of examples, which are not restrictive.

Fig. 1

shows typical main pixel satellite pixel ensembles;

Fig. 2

shows different variants of main with satellite pixels;

Fig. 3

shows a schematic representation of a traversed over a printing medium ink jet printhead and the case generated main and satellite printing pixels;

Fig. 4

shows a schematic representation of a nozzle plate on an ink jet print head in cross section;

Fig. 5

shows a schematic representation of print pixels consisting of main and satellite pixels;

Fig. 6

shows a schematic representation of print pixels, consisting of main and satellite pixels, which are superimposed with a latent image visible from a diamond-shaped screening ( Fig. 6C ).

Like reference numerals in the figures designate like elements, respectively.

In Fig. 1 Two typical main pixel satellite pixel ensembles are shown. The respective satellite pixel B is assigned to the corresponding main pixel A. It is located in a defined relative position to the main pixel A, in the present case approximately in the "7 o'clock position". In the left part of this figure, the satellite pixel B is not so far away from the main pixel A that both pixels are separated from each other. In the right part of the figure, both pixels are separated from each other. This can be achieved each time by adjusting the deflection when ejecting the ink drops from the print head. Various embodiments of matrices of major and associated satellite pixels are shown in FIG Fig. 2 shown.

In Fig. 3 schematically a printhead 1 is shown, which is moved in a printing direction 2 via a printing medium 3, for example a polymer film. From ink outlet openings 4 at the bottom of the printhead 1 single ink drops emerge, which are initially formed in the form of droplets and then split into a main drop and a satellite drop. The main drop is ejected along the normal to the plane formed by the underside of the print head 1 in which the exit openings 4 are located. The path of the main drop is marked 5. The main drop forms the main pixel 11. The satellite drop is ejected onto the polymer film 3 in a direction deflected from the normal. This path is marked 6. The satellite drop forms the satellite pixel 12. The angle at which the satellite drop is deflected with respect to a plane defined by the printing direction 2 and the main pixel 11 is denoted by β . The angle at which the satellite pixel 11 appears on the polymer film 3 relative to the main pixel 12 to the printing direction 2 is denoted by α .

In Fig. 4 a deflection device 7 is shown schematically on a drop generator 8 of a print head 1. The droplet generating device 8 has outlet openings 4. The deflection device 7 is provided with channels 9 whose inlet openings 10 are aligned with the outlet openings 4 of the droplet generating device 8. The channels 9 are S-shaped and thus deflect the satellite drops, while the deflection of the trajectories of the main drops is negligible. The satellite drops are deflected in the example shown to the left.

To produce an ink jet printed pattern on a polycarbonate film, the following ink compositions were prepared:

Example 1: Preparation of polycarbonate derivatives for an ink composition as a binder

149.0 g (0.65 mol) of bisphenol A (2,2-bis (4-hydroxyphenyl) -propane, 107.9 g (0.35 mol) of 1,1-bis (4-hydroxyphenyl) -3 , 3,5-trimethylcyclohexane, 336.6 g (6 mol) of KOH and 2700 g of water are dissolved in an inert gas atmosphere with stirring, then a solution of 1.88 g of phenol in 2500 ml of methylene chloride is added Solution will be at pH 13 to 14 and 21 to 25 ° C introduced 198 g (2 mol) of phosgene. Thereafter, 1 ml of ethylpiperidine is added and stirred for 45 min. The bisphenolate-free aqueous phase is separated off, the organic phase, after acidification with phosphoric acid, washed neutral with water and freed from the solvent.

The polycarbonate derivative shows a relative solution viscosity of 1.263. The glass transition temperature is determined to be 183 ° C. (DSC).

Example 2: Preparation of a liquid preparation suitable for the production of an ink jet ink

A liquid preparation is prepared from 17.5 parts by weight of the polycarbonate derivative from Example 1 and 82.5 parts by weight of a solvent mixture according to Table I (data in% by weight, based on the solvent mixture). Table I material Wt .-% mesitylene 2.4 1-methoxy-2-propanol 34.95 1,2,4-trimethylbenzene 10.75 Ethyl 3-ethoxypropionate 33.35 cumene 0.105 Solvent naphtha 18.45

A colorless, highly viscous solution with a solution viscosity at room temperature of 800 mPa.s is obtained.

Example 3 Production of an Ink Jet Printing Ink Used According to the Invention

In a 50 ml wide-mouth threaded glass 10 g of polycarbonate solution from Example 2 and 32.5 g of the solvent mixture from Example 2 are homogenized with a magnetic stirrer (4% PC solution). A colorless, low-viscosity solution having a solution viscosity at 20 ° C. of 5.02 mPa.s is obtained.

The polycarbonate solution obtained is additionally admixed with about 2% of Pigment Black 28. The result is an ink by means of which black and white images can be printed on polycarbonate films. By an equivalent addition of other pigments or dyes can be prepared according to monochrome and / or colored inks.

A change in the resolution of a pixel pattern printed with the ink almost does not occur in a joining operation in which the substrate layer printed with the pixel pattern is connected to a substrate layer arranged above it. This means that the pixel pattern is maintained in almost the same resolution even after lamination.

An optical examination of the composite otherwise gives no discernible phase boundary. The composite shows up as a monolithic block, which also resists delamination attempts outstanding.

This black ink is used with an inkjet printer with a printhead in accordance with Fig. 4 is modified, a pixel pattern printed on a polycarbonate sheet. It results in the Fig. 5 reproduced pixel matrix. Each of the print pixels is bimodal and consists of a larger main pixel and a smaller satellite pixel. The satellite pixel appears at an angle α to the transport direction (defined from right to left by the rows of print pixels) of approximately 60 ° relative to the main pixel to which it is associated.

Example 4: Formation of satellites on a pattern produced by ink-jet printing on surfaces previously rendered hydrophobic in diamond-shaped structures.

To produce a multi-colored passport photograph of a person, several color separations of the image are made in magenta, cyan, yellow and black.

In a first printing process, the main pixels are printed with associated satellite pixels on a first polycarbonate film ( Fig. 6A ).

Thereafter, a further polycarbonate film is first hydrophobized in a printing area with a diamond-shaped pattern. The diamonds are so large that at least one print pixel can be printed completely afterwards. For this purpose, the polycarbonate film is printed in a waterless offset process, the so-called Toray process, with a UV-curable and invisible to the human eye color. This color is silicone-containing, without colorants and optionally provided with fluorinated binder proportions. For printing, a print motif in the form of diamond lines is copied onto a printing form and printed on a PC film. This will make the in Fig. 6B Diamond lines, not visible to the human eye, printed on the surface.

Thereafter, a color separation of the passport photograph of the person in yellow is printed on the polycarbonate film by means of ink-jet printing in the print area rendered hydrophobic in partial areas. The ink composition used for this purpose corresponds to that of Example 3. In this case, each printing pixel is printed in the form of a main pixel and a satellite pixel appearing at an angle α relative to the main pixel with respect to the printing direction. This angle α is indicated by a 1 o'clock position. Where the diamond-shaped rasterization is located, the pixels can not be printed ( Fig. 6C ).

Further color separations of the passport image in yellow, cyan and magenta are printed in the same way on previously diamond-structured hydrophobized polycarbonate films by means of inkjet printing in a printing area corresponding to the printing area of the first polycarbonate film. The ink compositions are those of Example 3. However, instead of Pigment Black 28, suitable dyes are used to print the yellow, cyan and magenta color separations. The inkjet printhead is driven in all three cases so that satellite drops are ejected at an exit angle β ≠ 0 opposite to a plane defined by the printing direction and the main pixels. By using suitable deflection devices, printed images corresponding to those of Fig. 6C are similar, although the orientation of the satellite pixels on the main pixels is different in each case. In each color separation, another angle α at which the satellite drops strike the polycarbonate sheet relative to the main drops from the trajectory of the main drops is set: the position of the satellite pixels of the yellow color separation becomes relative to that of the main pixels in a 4 o'clock position set. The location of the satellite pixels of the cyan color separation is relative to that of the Main pixels set in a 7 o'clock position. And the position of the satellite pixels of the magenta color separation is set relative to that of the main pixels in a 10 o'clock position. In any case, the satellite drops are partially recognizable and partially suppressed by the diamond patterns.

The films are then stacked and laminated. It forms a monolithic composite of the films. The printed color separations in the layer composite can be assigned to the individual layers of the layer composite: the black color separation can be recognized by the fact that this satellite pixel contained in the 1 o'clock position; the yellow color separation is indicated by the fact that this satellite pixel is in the 4 o'clock position; The cyan color separation is indicated by the fact that this satellite pixel is in the 7 o'clock position, and the magenta color separation is indicated by the fact that it contains satellite pixels in the 10 o'clock position.

It should be understood that the examples and embodiments described herein are for illustration only, and that various modifications and changes to the examples and embodiments as well as combinations of features described in this application will be apparent to those skilled in the art.

Claims (14)

1. Polymer layer composite for a security and/or valuable document, comprising at least two materially interconnected polymer layers, wherein print layers comprising of print pixels are applied to at least one surface of at least one of the polymer layers in a printing region, wherein the print layer is produced by ink-jet printing, characterised in that the print pixels consist in each case of a main pixel and at least one satellite pixel associated with the main pixel, and the presence of satellite pixels in addition to the main pixels with which they are associated represents a security feature of the security and/or value document.
2. Polymer layer composite for a security and/or valuable document according to claim 1, characterised in that the print layer reproduces a personalised and/or individualised feature.
3. Polymer layer composite for a security and/or valuable document according to any one of the preceding claims, characterised in that the print layer is produced with an ink-jet printing head on one of the surfaces, and that each satellite pixel, relative to a respective main pixel with which it is associated, is produced with a specified orientation to the respective main pixels on the surface.
4. Polymer layer composite for a security and/or valuable document according to claim 3, characterised in that each satellite pixel, relative to the main pixel with which it is associated, is produced at a specified angle α to a connection line of adjoining printed main pixels on the surface, wherein α ≠ 0° and α ≠ 180°.
5. Polymer layer composite for a security and/or valuable document according to any one of the preceding claims, characterised in that the respective print layers in the polymer layer composite are arranged on internally located surfaces of the layers of the composite.
6. Method for producing a polymer layer composite for a security and/or valuable document, comprising at least two materially interconnected polymer layers, comprising the method steps: providing the polymer layers for the polymer layer composite, formation of respective print layers consisting of print pixels on at least one surface of at least one of the polymer layers in a printing region and connecting of the polymer layers with one another, wherein the print layer is produced by means of ink-jet printing, characterised in that the print pixels consist in each case of a main pixel and at least one satellite pixel associated with the main pixel, and the presence of satellite pixels in addition to the main pixels with which they are associated represents a security feature of the security and/or value document.
7. Method for producing a polymer layer composite for a security and/or value document according to claim 6, characterised in that the print layer is applied in the form of a personalised or individualised feature.
8. Method for producing a polymer layer composite for a security and/or value document according to any one of claims 6 - 7, characterised in that the print layer is produced by an ink-jet printing head on one of the surfaces, and that each satellite pixel, relative to a respective main pixel with which it is associated, is produced on the surface at a specified angle α to the direction with which the ink-jet printing head and the surface are moved relative to one another.
9. Method for producing a polymer layer composite for a security and/or value document according to claim 8, characterised in that, irrespective of the direction in which the ink-jet printing head and the surface are moved relative to one another, each satellite pixel, relative to the main pixel with which it is associated, is produced on the surface at a specified angle α to a connection line of adjoining printed main pixels.
10. Method for producing a polymer layer composite for a security and/or value document according to any one of claims 8-9, characterised in that the angle α is adjusted by adjustment of a device provided at the ink-jet printing head for deflecting the satellite ink drops emerging from the printing head, or adjusted in that the device for deflecting the satellite ink drops emerging from the printing head is a device comprising continuous openings, and which is arranged immediately adjacent to outlet openings of the printing head.
11. Method for producing a polymer layer composite for a security and/or value document according to claim 10, characterised in that the device for deflecting the satellite ink drops emerging from the printing head is adjusted and/or configured in such a way that the ink liquid emerging from outlet openings of the printing head and forming the satellite pixels emerges at an angle β in relation to a plane which is determined by the respective main pixel and the direction in which the printing head and the surface are moved relative to one another.
12. Method for producing a polymer layer composite for a security and/or value document according to any one of claims 6-11, characterised in that the respective print layers of the polymer layer composite are arranged in internally located surfaces of the polymer layers of the composite.
13. Security and/or valuable document containing a polymer layer composite in accordance with any one of claims 1-5.
14. Use of the security and/or valuable document according to claim 13 as a personal identity document, passport, credit card, cash card, cash payment card, customer card, visa card, ID card, or driving licence.

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