EP2367692B1 - Value document with matte and glossy surface areas and method for the production thereof - Google Patents

Description

The invention relates to a document of value, such as a banknote or identity document, which has a flat substrate, is provided on at least one surface with an anti-counterfeiting agent and at least on the surface provided with the anti-counterfeiting agent or on one of the anti-counterfeiting surfaces a coating with matt areas and shiny or non-matt areas. A glossy appearance reveals the coating surface where it covers the anti-counterfeiting agent while displaying a dull appearance in the remaining areas. The invention also relates to a method for producing such a document of value with matt and glossy surface areas. Furthermore, the invention relates to value-document sheets and value-document endless materials with a multiplicity of individual value-documents according to the invention and to methods for their production.

Security documents, such as banknotes or identity documents, in particular banknotes, must be protected against counterfeiting and are provided for this purpose with suitable equipment, an "anti-counterfeiting security". Anti-counterfeiting means are security elements, such as security threads, window security threads, foil applications, which have a transparent or metallized embossed hologram, blind embossing, printing or printing and embossing technically produced "latent images" that reflect different information from different viewing angles, prints that contain optically variable pigments and appear at different viewing angles in varying colors, or imprints of metallic effect colors that shine metallic, for example in gold, silver or bronze tones. Also through openings, ie windows (holes, which be closed by a transparent or partially transparent film or alternatively transparent films, which are only partially provided with an opaque coating) in the value documents win as anti-counterfeiting in importance, the windows are often combined with additional security elements, for example, to be tested in transmitted light security elements.

To ensure the longest possible lifespan or useful life, value documents are often provided with protective coatings. In addition to their protective function, the coatings must meet additional requirements: In the case of banknotes in particular, it is important that the typical feel of the substrate is not influenced by the coating. The haptic character of a banknote is mainly expressed by its grip and bending stiffness, and it also has a characteristic sound when deformed and wrinkled.

Special importance is also attached to the optical properties of valuable document coatings. The coatings should preferably provide a matte surface appearance, since dull coatings do not adversely affect the visual appearance of a value document, as opposed to very smooth coatings, provide a better grip to the document of value when dropped, stacked and gripped, thereby preventing slippage of the stacked sheets Avoid transport processes (influenced by static and sliding friction), and also facilitate the mechanical inspection of the safety elements. A security element, which is surrounded by a matt coating, is easier to detect because of the much lower reflections from optical sensors or is not disturbed by highlights.

Value documents with paper substrate are often printed by intaglio printing. Due to the high pressure with which the substrate is pressed against the printing plate in this process, the paper surface is in the non-engraved, d. H. non-ink-bearing areas of the printing plate strongly compressed and smoothed. As a result, an undesired gloss can be produced on the paper substrate which can be reduced again by a matt coating applied thereafter.

While it is generally desirable to give value documents a rather dull surface appearance, the visual appeal of tamper-evident means must not be adversely affected by a dull coating, i. H. toned down. In certain cases, it may even be very desirable to visually emphasize the anti-counterfeiting means to specifically direct a viewer's attention to it. Hiding under a matt coating would then be very counterproductive, but the anti-counterfeiting agent should be visually highlighted and emphasized by the strongest possible coating.

In order to solve the problem of giving value documents a matt surface appearance, without impairing the perceptibility of counterfeiting means, or even highlighting this visually, is in WO 02/094577 proposed to provide a still unprinted or already printed security on at least one side with a protective layer which is formed by a matt lacquer or a thin plastic film with a matte surface, said protective layer in the region of a security element interrupted, ie recessed, is. In the subareas of the security surface in which there is a security element and in which the matte protective layer has been recessed, a Protective layer can be applied, which consists of a gloss varnish. The protective layer of gloss varnish is particularly recommended for security elements that are subject to heavy soiling and / or significant abrasion without coating, for example metallic effect color imprints, blind embossing and printing "latent images".

The successive varnishes with a matt varnish and a gloss varnish must be as accurate as possible, with the part surface recessed in the matt varnish being printed exactly with a gloss varnish. For technical reasons, an exact registration is hardly possible, which is why overlapping is used, with an overlap zone is desired, which is not greater than about 2 mm.

As matt paints or gloss paints, aqueous dispersions or radiation-curing systems are used. The paints are applied by flexographic printing or screen printing. The flexographic printing process is a printing process that works well for large, high-speed presses and high throughputs of substrate.

This in WO 02/094577 However, disclosed methods for furnishing value documents with coatings that have both matte and glossy surface areas, but has some disadvantages. Since the two paints, matt varnish and gloss varnish, must be printed accurately, both print processes require specially structured flexographic printing plates. However, as the name suggests, flexographic printing plates are flexible, and due to this flexibility, it is not possible to achieve an absolutely precise, register-accurate print image. Furthermore, the resolution of the flexographic printing process is significantly lower than, for example, offset printing. Because flexographic printing is a direct printing process (ie it is transferred from the printing plate directly to the substrate drive (ie it is printed by the printing plate directly on the substrate) is also the surface texture in the print quality. In addition, the flexographic printing plates consist of polymers which tend to swell (caused by the ingredients of the paint), so that a constant adjustment of the contact pressure is required, resulting in high downtime. The plates also wear out quickly and are comparatively expensive. However, an offset printing process is less suitable for the UV varnishes printed because the transferable layer thickness is lower.

Furthermore, heavily matted UV coatings are problematic in terms of processing since they tend to settle the matting agent.

document EP-A-1 685 974 discloses a value document according to the preamble of claim 1.

Based on this prior art, the present invention, the object value documents with anti-counterfeiting agents with a frosted coating, preferably a heavily frosted coating, but at least at the points where anti-counterfeiting means are non-dull, d. H. shiny, has areas to provide. The object of the invention is also to provide a method for producing such value documents. The disadvantages of the prior art should be avoided. In particular, it should be avoided that the coating must be composed of matt and glossy subregions, which must be printed in each case in exact registration with each other.

The object of the present invention is, in particular, the coating of banknotes with optically perceivable security elements and / or windows, ie recesses in the substrate. The banknotes should be equipped with a heavily matted coating, which is however in the range of Security elements whose visual perceptibility should not be disturbed and / or are shiny or not dull in the area of the window.

The coating should be suitable for various security substrates, i. H. for paper substrates and in particular also for polymer substrates or film composite substrates. It should not affect the properties of the substrate, which is particularly important in banknotes, protect the coated security and extend its life.

The object is achieved by the value document and the method as indicated in the independent claims. Particular embodiments are given in the dependent claims.

According to the invention, the value document, in particular a banknote, is provided with a "hybrid coating", ie. H. a double layer of two different coating systems.

Applied to the substrate is a "poorly wettable composition". This is a composition suitable for offset printing, i. H. a special offset printing ink, wherein no or preferably no visually visible colorant is contained, but only binder and the usual additives are included. In the following, we speak of an "offset printing ink". When applying the offset printing ink, the area of the counterfeiting device or the counterfeiting means (holograms, blind embossing, security threads, windows, etc.) is recessed with register accuracy.

After a defined intermediate drying, preferably without drying unit, ie no active drying, for example by hot-air dryer, IR-dryer or UV lamp, the offset ink is applied to a layer of an electron beam curing or electromagnetic radiation curing coating system. The defined intermediate drying results from the machine speed, the construction of the printing machine (distance to the next printing unit), the impact behavior of the substrate and the composition of the offset ink. Preference is given to UV-curing coating systems. The job is carried out over the entire surface, ie both in the areas in which the offset printing ink was previously applied, as well as in the areas of anti-counterfeiting. The result is a surface that shines in the field of anti-counterfeiting, but appears matte in the areas in which the radiation-curing composition was applied to the still wet offset ink. The radiation-curing composition is referred to below as "UV varnish". UV coatings are the preferred radiation curing compositions.

Alternatively, instead of the offset printing ink, a water-based paint can also be used. This should hinder the wetting by the jet-drying lacquer by adding wetting-disturbing ingredients, as they are known to a person skilled in the art. This can also be controlled by an incomplete physical drying, wherein in the case of a water-based paint, the provision of a drying unit may be useful. Drying is influenced by the volume flow of the hot air, the power of the IR radiator, the design of the dryer, the impact behavior of the substrate and the paint formulation.

The reason for the formation of dull and non-dull, ie shiny, areas lies in the different wettability of the substrate to which the UV varnish is applied. Generally, the better and more trouble-free the wetting, the glossier the surface of the UV varnish. According to the invention, therefore, the wetting is disturbed by the UV varnish in the areas in which a matte surface is desired. The poor wettability or wetting disorders are achieved according to the invention in two ways, which are preferably used in combination: on the one hand by the choice of a suitable composition of the offset printing ink, and on the other by the choice of the appropriate application time of the UV varnish and a suitable composition of the UV varnish.

Offset inks inherently have the property of being difficult to wet by UV varnishes; Therefore, typically, in offset printing with in-line coating when using UV varnishes, a water-based primer is applied to the oxidatively drying inks and dried in order to achieve adequate wetting of the UV varnish. In the present case, however, no good wetting is desired.

Offset inks contain colorants in the form of organic or inorganic pigments or dyes (preferably not included in the present invention), binders and additives such as driers, mineral oil, wax dispersions and other additives known to those skilled in the art. The binders typically consist of phenol-modified rosin resins, hydrocarbon resins, linseed oil standing oils, mineral oils and linseed oil. The drying takes place physically (by evaporation of the mineral oils, by knocking low-molecular oils or binders into the substrate or the ink-accepting layer of the substrate) and / or oxidatively.

Depending on the substrate used and the requirements of the printed product (chemical-physical resistance, gloss, odor, etc.), the exact composition of the offset ink takes place.

When coating with offset printing ink, it is desirable to wetting the substrate as trouble-free as possible. It is known that the interfacial tension of the substrate to be printed must be greater than that of the paint or the lacquer in order to allow a good trouble-free wetting. When printing non-polar films, such as polyethylene or polypropylene, it may therefore be necessary to adapt the surface tension of the substrate to the coating composition. The adaptation takes place, for example, by corona, plasma or gas flame treatment of the substrate surface or by means of primer application on the substrate surface.

• 0 % bis 20 % Alkydharze,
• 0 % bis 10 % pflanzliche Öle,
• 0 % bis 10 % Mineralöle,
• 0,5 % bis 2 % Sikkative bzw. Trockenstoffe,
• 0 % bis 3 % Wachse,
• 0 % bis 3 % Silikonöl und
• der verbleibende restliche Anteil aus Bindemitteln, bestehend aus modifizierten Kohlenwasserstoffharzen.

The offset inks used are made up (all percentages here and below are by weight):

• 0% to 20% alkyd resins,
• 0% to 10% vegetable oils,
• 0% to 10% mineral oils,
• 0.5% to 2% siccatives or dry substances,
• 0% to 3% waxes,
• 0% to 3% silicone oil and
• the remaining amount of binders consisting of modified hydrocarbon resins.

• 20 % bis 75 % Bindemittel 1 (Printorob AL 399) von Erbsöl (modifiziertes Isophthal-Alkydharz) in Mineralöl und Leinöl gelöst,
• 25 % bis 70 % Bindemittel 2 (Bremapal 2150) von Kraemer (phenolharzmodifizierter Harzester) in Mineralöl und Leinöl gelöst,
• 0 % bis 2 % mikronisiertes Polyethylen-Wachs oder PTFE-Wachs (10 bis 20 µm D90),
• 0,1 % bis 0,5 % Trockenstoff Octa-Soligen Cobalt 8 %-ig von OMG,
• 0,5 % bis 1,0 % Trockenstoff Octa-Soligen Mangan 8 %-ig von OMG.

For example, the offset printing ink used is an oil-based printing ink of the following composition:

• 20% to 75% of binder 1 (Printorob AL 399) of crude oil (modified isophthalic alkyd resin) dissolved in mineral oil and linseed oil,
• 25% to 70% of binder 2 (Bremapal 2150) from Kraemer (phenolic resin-modified rosin ester) dissolved in mineral oil and linseed oil,
• 0% to 2% micronized polyethylene wax or PTFE wax (10 to 20 μm D90),
• 0.1% to 0.5% dry octa-Soligen cobalt 8% of OMG,
• 0.5% to 1.0% dry octa soligen manganese 8% from OMG.

• 20 % bis 30 % Bindemittel 1 (Printorob AL 399) von Erbsöl (modifiziertes Isophthal-Alkydharz) in Mineralöl oder Ester gelöst,
• 60 % bis 70 % Bindemittel 2 (Bremapal 2150) von Kraemer (phenolharzmodifizierter Harzester) in Mineralöl oder Ester gelöst,
• 0- 2 % mikronisiertes Polyethylen-Wachs oder PTFE-Wachs (10 µm bis 20 µm D90),
• 0,1 % bis 0,5 % Trockenstoff Octa-Soligen Cobalt 8 %ig von OMG,
• 0,5 % bis 1,0 % Trockenstoff Octa-Soligen Mangan 8 %-ig von OMG.

Another alternative example of an offset ink is a low yellowing oil pressure varnish of the following composition:

• 20% to 30% of binder 1 (Printorob AL 399) of crude oil (modified isophthalic alkyd resin) dissolved in mineral oil or ester,
• 60% to 70% of binder 2 (Bremapal 2150) from Kraemer (phenolic resin-modified rosin ester) dissolved in mineral oil or ester,
• 0-2% micronized polyethylene wax or PTFE wax (10 μm to 20 μm D90),
• 0.1% to 0.5% dry octa-Soligen cobalt 8% of OMG,
• 0.5% to 1.0% dry octa soligen manganese 8% from OMG.

Generally formulated, the oil pressure varnish thus consists of hard resins (eg phenolic resin-modified hydrocarbon resins), alkyd resins (eg Linseölalkydharze), mineral oils (boiling range 200 ° C to 360 ° C), vegetable oils (linseed oil, wood oil, etc.), siccatives (cobalt / Manganese octoates) and adjuvants, such as waxes (eg, micronized PE and / or PTFE waxes), to improve abrasion resistance. About the proportion of vegetable oils, alkyd resins and the concentration of siccatives here the degree of yellowing Controlled: the lower the proportion, the lower the yellowing, due to cleavage products, which arise during the oxidative drying.

Particularly preferably, the lacquer used shows the lowest possible yellowing with high chemical and physical resistances, as they are usually required by banknotes.

It is also possible to add a very small amount of pigment blue pigment (e.g., Blue 15: 3, phthalocyanine pigment) to the oil pressure varnish to neutralize a yellowing yellow due to yellowing. The pigment concentration is then 0.05% to 0.2%

The poor wettability of the offset inks can be promoted by suitable variations of the composition of the offset inks.

The surface tension of the oil pressure varnish can be further reduced, for example, by adding 0.5% to 4% of silicone oil in order to enhance the repellent effect of the subsequent gloss varnish.

A similar effect appears when the physical drying of the oil pressure varnish is prolonged by a higher compatibility of the binder. The compatibility of the binder here is the dissolving power of the resin by the solvent used, e.g. Mineral oil, understood.

Another way of delaying the physical drying is by a higher proportion of vegetable oils, such as linseed oil, soybean oil or wood oil, which dry only oxidatively, and / or a use of higher boiling mineral oils (eg mineral oils with a boiling range of 210 ° C to 280 ° C by mineral oils with a boiling range of 280 ° C to 360 ° C or replaced by mineral oils with a higher aromatic content).

Suitable offset printing inks are available, for example, from Epple (article Nos. 1290-03 or 1523).

Instead of an offset printing ink from mineral oils, synthetic mineral oils or vegetable oils, water-based paints or dispersion paints can also be used. Such coatings also lead to a wetting disorder of the UV coating at an insufficient drying. The physical drying of the water-based paint can for example be controlled or extended by the parameters of the drying unit (volume flow for hot air, IR emitter power) and / or by substitution of water by glycol. The lacquer can additionally be provided with hydrophobic groups or hydrophobic particles (for example wax particles - paraffin or carnauba wax - or micronized PE, PTFE, etc.), which accumulate distributed on the surface and thus lead to a partial repulsion.

The described offset printing inks with and without visually invisible colorants, such as, for example, luminescent substances, and water-based lacquers with and without visually invisible colorants are difficultly wettable compositions in the context of the present invention.

The offset printing ink or the water-based paint can also be printed as a fine grid in order to produce spots with partially good and poor wettability by the UV varnish. This makes it possible, for example, abzusoften edge areas, ie to realize a gloss or a matt course. This can be at individual forgery-proof features, such as For example, a hologram patch, be advantageous to better conceal Paßschwankungen the patch.

• 50 % bis 80 % Prepolymere,
• 10 % bis 40 % Reaktivverdünner,
• 3 % bis 8 % Fotoinitiatoren,
• 0 % bis 3 % Wachse,
• 0 % bis 1 % Anti-Slip-Mittel,
• 0 % bis 1 % Netzmittel,
• 0 % bis 1,5 % Entschäumer,
• 0 % bis 5 % Trocknungsbeschleuniger.

The UV varnish, or generally the radiation-curable composition, is a conventional UV varnish, in particular a radically crosslinking UV varnish or a cationically crosslinking UV varnish with corresponding photoinitiators. Particularly suitable UV lacquers are free-radical lacquer systems with the following composition:

• 50% to 80% prepolymers,
• 10% to 40% reactive diluent,
• 3% to 8% photoinitiators,
• 0% to 3% waxes,
• 0% to 1% anti-slip agent,
• 0% to 1% wetting agent,
• 0% to 1.5% antifoam,
• 0% to 5% drying accelerator.

• 60 % eines Polyester-Acrylats, z.B. Laromer PE 55 F der Fa. BASF,
• 10 % eines Acrylsäureesters, z.B. Laromer TMPTA der Fa. BASF,
• 21 % eines Acrylsäureesters (Reaktivverdünner), z.B. Laromer HDDA der Fa. BASF,
• 5 % eines Fotoinitiators, z.B. Darocure 1173 der Fa. CIBA,
• 3 % eines reaktiven Amins als Trocknungsbeschleuniger, z.B. Ebecryl P 115 der Fa. UCB,
• 0,5 % eines Entschäumers auf Silikonbasis, z.B. Coatosil 100 E, der gegebenenfalls wegelassen werden kann, um die erfindungsgemäße Benetzungsstörung zu der Offsetfarbe zu verstärken,
• 0,5 % eines Anti-Slip-Mittels, z.B. Dow Corning 57 der Fa. DOW.

By way of example, such a radical paint system has the following composition:

• 60% of a polyester acrylate, eg Laromer PE 55 F from BASF,
• 10% of an acrylic acid ester, eg Laromer TMPTA from BASF,
• 21% of an acrylic acid ester (reactive diluent), eg Laromer HDDA from BASF,
• 5% of a photoinitiator, eg Darocure 1173 from CIBA,
• 3% of a reactive amine as a drying accelerator, eg Ebecryl P 115 from UCB,
• 0.5% of a silicone-based antifoam, eg Coatosil 100 E, which may optionally be omitted to enhance the wetting disturbance of the present invention to the offset color;
• 0.5% of an anti-slip agent, for example Dow Corning 57 from DOW.

When choosing photoinitiators, it should be noted that any safety features based on fluorescent substances will not be disturbed. Therefore, photoinitiators are preferred which absorb in the short-wave (200 nm to 279 nm) and in the medium-wave (280 nm to 330 nm) UV range. In order to ensure a good or sufficient drying of the coatings, it makes sense to match the radiators of the UV dryer used to the wavelength range of the photoinitiators used.

Suitable UV lacquers are offered, for example, by Vegra under the item number VP 1038/050 (high-gloss UV lacquer based on a free-radically polymerizing acrylate system).

The UV varnish is applied directly to the not yet fully dried offset printing ink. Preference is given to using a UV varnish which contains no wetting aids, such as silicone oils or wetting agents.

An important consideration for achieving a matt surface appearance is the application time of the UV varnish to the poorly wettable composition. UV varnishes are repelled by not yet dried offset printing inks, whereby the extent of the repulsion can be influenced by the degree of drying. Therefore, to achieve a defined repulsion, and thus to achieve a defined degree of matting, a defined intermediate drying of the offset printing ink is provided. This requires an in-line coating, ie one Application of offset printing ink and UV varnish in one pass, preferably in a sheet-forming machine In this way, stable, reproducible results are obtained.

By using an active intermediate drying, such as hot air / IR, one could accelerate the physical drying of the offset ink and would reduce the wetting disturbance by the following radiation-curing lacquer and thus also reduce the degree of matting. Therefore, such use is not usually desired in the case of offset printing inks.

The manufacturing process is performed as follows:

The coating is preferably carried out not on individual value documents, but on value document sheets or on continuous value document webs, each with a plurality of individual value documents.

The application of the offset printing ink takes place, depending on the wetting properties of the substrate, on the untreated surface or optionally on a wetting-promoting pretreated substrate surface. Basically, the type of application of the offset ink is arbitrary, but since typically large amounts of large format sheets or continuous materials are to be printed, preferred are those which are suitable for high-speed, large printing presses. For this purpose, high pressure, indirect high pressure, flexo printing and offset printing are suitable. The application in the offset printing method is preferred because the offset printing due to the rigid printing plate is more precise than the flexographic printing and thus a better registration accuracy can be achieved. In addition, there is little risk of producing pinch edges.

The application of the offset printing ink is carried out with register accuracy limited to the areas which should show a matt surface as a result. Preferred is a plot in the offset printing unit (indirect printing method) by means of offset or Nyloprintplatte (high-pressure plate). The inking of the offset printing ink is preferably in a range of 0.5 g / m ² to 3 g / m ² , more preferably in a range of 0.8 g / m ² to 1.2 g / m ² .

Subsequently, an intermediate drying of the coating takes place. Drying is carried out exclusively by the displacement of low molecular weight oils or binders in the substrate or in the ink receiving layer of the substrate, oxidatively, or by the evaporation of solvents. Active drying by hot air or IR radiation is usually not required.

Subsequently, the UV varnish is applied inline to the intermediate dried offset printing ink. The optimum application time is determined in each case by preliminary preliminary experiments, depending on the compositions of the offset printing ink and the UV varnish, the layer thickness of the offset printing ink and the degree of desired mattness. The type of application of the UV varnish is basically arbitrary, but offset printing and flexographic printing are preferred. Particularly preferred is the fast flexographic printing process. The disadvantages associated with the flexographic printing process, such as lack of precision in the case of the required passergenauem lacquer application due to the flexible printing plate, the swelling of the printing plate by UV coatings, etc. pose no problem here, since the coating is applied over the entire surface and printed on a blanket on the substrate can. The squeezing edges that occur in flexographic printing are also no problem with full-surface application.

The application of the UV high-gloss lacquer therefore preferably takes place by means of a flexographic printing unit, more preferably via an anilox roller in the chambered doctor blade system onto a photopolymer plate (flexographic printing plate, eg Gold A from Flintgroup) or a stripped or partially (in the region of the surface to be coated) underlayed blanket is printed on the substrate.

The paint application is in the range of 1 g / m ² to 4 g / m ² , preferably in the range of 1.5 g / m ² to 3 g / m ² , depending on the scoop volume of the anilox roller used (theoretical scoop volume of 6 g / cm ³ to 16 g / cm ³ , grid structure ART or Haschuren, etc.), the temperature-dependent rheology of the paint, the machine speed and the surface tension of the paint and the substrate to be coated.

Subsequently, the drying is carried out by means of UV radiation or with another suitable radiation, if no UV-radiation-curing lacquer was used. The drying of the offset ink is finally carried out by oxidative drying and only to a small extent by further knocking off mineral oil.

In the areas where the high-gloss paint was applied to the offset printing ink, the coating surface now shows a dull appearance. In the other areas, where a trouble-free wetting could take place, the surface is not matt or shiny. The effectiveness of the "hybrid coating" according to the invention for producing matt and glossy surface areas can be detected metrologically by gloss measurements. The measurements to be performed are related to the Figures 3a, 3b and 3c explained.

Fig. 1

eine Aufsicht auf ein erfindungsgemäßes Wertdokument,

Fig. 2

eine Schnittansicht des in Fig.1 dargestellte Wertdokuments entlang der Linie A-A',

Fig. 3a

eine lichtmikroskopische Aufnahme einer unbeschichteten Banknote mit Polymersubstrat,

Fig. 3b

eine lichtmikroskopische Aufnahme der mit einem hochglänzenden UV-Lack beschichteten Banknote von Fig. 3a, und

Fig. 3c

eine lichtmikroskopische Aufnahme der mit einer erfindungsgemäßen Beschichtung ausgestatteten Banknote von Fig. 3a.

The present invention will be explained in more detail with reference to figures. The figures are not to scale and proportions. Show it:

Fig. 1

a view of a value document according to the invention,

Fig. 2

a sectional view of the in Fig.1 represented value document along the line A-A ',

Fig. 3a

a light micrograph of an uncoated banknote with polymer substrate,

Fig. 3b

a light-micrograph of the coated with a high-gloss UV varnish banknote of Fig. 3a , and

Fig. 3c

a light micrograph of the banknote equipped with a coating according to the invention of Fig. 3a ,

Fig.1 is a plan view of an inventive document of value 1, in the figure a banknote. The value document indicates its in Fig. 1 visible surface anti-counterfeiting means in the form of a hologram foil patch 10 and a window 12 on. The areas 18 of the banknote surface are coated with offset printing ink and UV varnish and show a matt surface appearance. The areas 19 of the banknote surface, ie the areas where the tamper-evident means 10 and 12 are located, are only coated with UV varnish and have a glossy surface appearance.

Fig. 2 is a sectional view of the in Fig.1 Banknote shown in plan along the line A-A '. The value document 1, in the present case a banknote, has a cotton-based substrate 2. Alternative substrate variants are plastic materials with opaque color adhesive layers partially applied symmetrically on both sides of the substrate, paper and composite materials, ie multilayer substrates comprising layers of plastic and paper, or hybrid-like substrates with nonwoven layers containing both pulp or cotton fibers and plastic fibers. The substrate 2 has as one of the anti-counterfeiting means a window 12 which, in the embodiment shown, is closed by a transparent plastic film 3 integrated into the substrate 2. The plastic film 3 could also extend over the entire surface of the substrate. As a further anti-counterfeiting agent, a security element 10 with a hologram is glued onto one of the surfaces of the substrate 2. On the opposite surface is an imprint 9 in the form of a lettering, a pictorial representation, a pattern or any other representation that is to be well perceived by a viewer. The banknote 1 is now to be provided with a matt coating over its full area, but this must not impair the transparency of the window 12 and the visual perceptibility of the hologram 10 and the imprint 9. In the areas of the imprint 9, the hologram 10 and the window 12, the coating must therefore not be dull. To produce a coating with matt areas and non-matt areas at the respectively required locations, the two surfaces 4, 4 'of the banknote 1 are each printed with a layer of offset printing ink (eg No. 1523 by Epple) 15, 15' , On the surface 4, the printing takes place in the offset printing process, taking into account the tolerances of upstream process steps, eg application of a patch, as accurate as possible paßgenau such that the entire surface 4 except those areas in which the hologram 10 and the window 12 are printed. On the surface 4 ', the layer 15' of offset printing ink is printed in register only in the region of the window 12. In the area of the lettering or other imprint 9, however, a narrow area of the surface 4 'is left around the imprint 9. After a defined intermediate drying of the layer 15, a layer 17 of UV varnish (VP 1038/050 from Vegra) is applied over the entire surface of the layer 15 by flexographic printing. Subsequently, the layer 17 is cured by UV radiation. In the coating of the back surface, the procedure is analogous: After defined intermediate drying of the layer 15 'of offset printing inks, a layer 17' of UV varnish is applied over the full area by flexographic printing and then cured by UV radiation. In this case, on the surface 4 of the substrate 2, the coating 14 according to the invention, consisting of the discontinuous layer 15 and the continuous layer 17 formed on the surface 4 'of the substrate 2, the coating 14' of the invention, consisting of the discontinuous layer 15 'and the continuous layer 17 '. The coating 14 has exactly at the points where the layer has 15 interruptions 16, so exactly at the points where the window 12 and the hologram 10 are, shiny surface areas 19, while the remaining areas 18 of the surface appear dull , The mattness of the surface areas 18 is due to the poor wettability of the layer 15 located at these locations below the layer 17. Analogously, the coating 14 'at the points where the layer 15' interruptions 16 ', shiny surface regions 19'. On the other hand, at the points where the layer 17 'is applied to the layer 15', the coating 14 'has matt appearance surface areas 18'. The glossy surface area 19 'is above the window 12.

It is preferred to provide the coating according to the invention in each case on the entire surface or on both surfaces of a value document. But of course also partial surface coatings of one or both surfaces are possible.

The Figures 3a, 3b and 3c show light micrographs of the surface of a banknote with polymer substrate. In Fig. 3a the banknote is uncoated, in Fig. 3b the banknote is coated with a high-gloss UV varnish (VP 1038/050 from Vegra), and in Fig. 3c the banknote is first coated with an offset printing ink (# 1523 from Epple) and then with the high gloss UV varnish (VP 1038/050 from Vegra). The surfaces are significantly different in terms of their structuring. In the Fig. 3c banknote coated according to the invention has a surface with a coarse worm-like structure, which leads to a strong light scattering and thus to loss of gloss. The light scattering depends on the size and the relief height of the worm structure. Instead of a worm structure, a coarse dot structure can also be formed.

The gloss values of the uncoated banknote, the banknote coated only with UV varnish and the banknote coated according to the invention were measured in each case. For this purpose, the surface to be measured is illuminated at a defined angle and the reflected light is measured photoelectrically. The measurements were carried out with a reflectometer at an angle of 60 ° according to DIN 67530, or ISO 2813, ASTM D 523 and BS 3900 Part D5, whereby the gloss values listed in the table below were obtained. "Matt" is a gloss value of less than 15%. The same measurements were also made on an analog coated banknote with a velin paper substrate. Gloss measurement (60 °) uncoated UV topcoat (VP 1038/050) Hybrid coating (1523 Epple, VP 1038/050 Vegra) Polymer substrate (Guardian® substrates from Polytec) (standard blind embossing) 3.4% 47.4% 9.0% Substrate made of vellum paper (standard blind embossing) 4.4% 27.7% 12.8% As can be seen from the table, the uncoated substrates have very low gloss values, so both show a dull appearance. The substrates coated according to the invention are also matt, the difference to the substrate coated with UV varnish being particularly clear in the case of the polymer substrate.

The present invention has many advantages over the prior art.

Since the coating according to the invention is composed of two individual layers, one of which is continuous, there can be no defects in the coating. There can also be no overlapping of matt and non-matt areas, since two different layers do not have to be printed in register, one after the other, but only one of the layers has to be printed precisely in register with the counterfeit securing means. In addition, a very high registration accuracy can be achieved in this printing process, since in the offset printing process, ie with rigid printing plates, can be printed.

The degree of dullness or, in other words, the gloss value, is controllable by the type of offset ink, the layer thickness of the offset ink and the extent of drying of the offset ink prior to application of the UV varnish. Another possibility of the control consists in the omission of leveling and wetting agents in the UV varnish.

Within the matt areas additional gradations in the degree of dullness can be realized. For example, two or more different offset printing inks can be used, which are wetted differently well by the UV varnish, so that different gloss values of the UV varnish result due to the differently pronounced wetting disorders. The different offset printing inks are preferably printed in register with each other, i. not printed on top of each other. In particular, one offset printing ink can be printed in offset printing or in high-pressure, and another offset printing ink can be applied in flexographic printing.

The same effect, ie different gloss values of the UV varnish, can also be achieved with a single offset printing ink if a rastering of the offset printing plate is undertaken. The gradations achieved by rastering the offset printing plate in the degree of dullness can be placed over the entire banknote over the whole area or in partial areas. For example, in the area of a window or other anti-counterfeiting device, as the proximity to the window / anti-counterfeiting agent increases, the gloss can gradually increase. Further, gradations in degree of dullness may represent motives such as micro stars and currency symbols, or micro-typefaces denoting, for example, the bill value or the country. In addition, very finely resolved matt structures can be realized (by a Scanning of the printing plate by means of dot or line grid). In this way, very finely resolved line structures can be generated, which in turn can be used to achieve moiré effects. The very finely resolved matt structures can be detected with the naked eye or by means of an aid, eg a thread counter or a magnifying glass, via the glancing angle. When the very finely resolved matt structures are applied in a window region of the banknote, they are additionally discernible when looking through the scattering.

In addition, no radiation-curing lacquer comes directly into contact with the substrate. This has the advantage that even with very porous substrates, as they are frequently found in the field of value documents, no residual monomers and free photoinitiators can remain as reactive components in the recesses and pores of the substrate. If matt UV coatings are used to produce matt coating areas, such components are usually still to be found in the capillaries of the substrate after radiation curing.

As UV lacquers only high-gloss UV lacquers can be used. High-gloss paints without matting agent are cheaper and much easier to process than paints with matting agent. They do not tend to separate or settle the matting agents and show a constant viscosity. Furthermore, these paints can be formulated with a lower viscosity.

Since only the offset ink has to be printed accurately, you only need a correspondingly equipped offset printing plate. The layer of UV varnish is printed over the entire surface, so it can be applied in a flexographic printing process using standard rubber blankets. A Swelling of the flexographic printing plates with the associated disadvantages, as occurs in a register-accurate printing of UV coatings, is avoided in this way.

The front coating and the back coating of a document of value can be done in the same plant without changing the printing plates. The plant will simply set up an offset printing unit for the offset ink with the required cutouts for the front and another offset printing unit for the offset ink with the required recesses for the back. The change from front to back coating is done by switching on the first or second offset printing unit. This is the case for machines without a turning device with the following equipment: at least two offset printing units and at least one flexographic printing unit.

The coating according to the invention can be used very universally. All substrates that can be printed with offset printing inks can be coated. H. Substrates based on paper, based on plastic, combination substrates (paper / plastic mixtures within a layer or multilayer substrates made of different materials), coated and uncoated substrates, flexible or inflexible substrates such. For example ID, credit or debit cards.

The coating according to the invention does not necessarily have to represent the uppermost layer of a value document. Rather, the coating can also be embedded; For example, a film lamination can be provided or a further lacquer layer can be applied. The coating can also be printed.

The offset printing ink and the UV varnish are preferably colorless and, apart from the matting, visually invisible. It is also possible to equip offset printing ink and / or UV varnish with additional features, for example a specific color. Offset ink and UV varnish can have the same hue or different hues. Further features with which offset printing ink and / or UV varnish can be provided are, for example, luminescence in different wavelength ranges by addition of suitable luminescent substances, or color plays by addition of pearlescent pigments, thin-layer pigments or liquid crystal polymers. The offset printing ink and the UV varnish can be equipped with the same or different characteristics. It is also possible to combine visually visible and visually invisible offset printing inks and / or UV varnishes by using two different printing plates in each case.

As mentioned above, additional gradations in the degree of dullness can be realized within the matt areas, for example by using two or more different offset inks, which are wetted differently well by the UV coating, so that due to the different wetting disorders different gloss values of UV varnish results. The offset printing inks should preferably have no intrinsic color visually. In particular, at least one of the offset printing inks used can have an additional anti-counterfeiting feature, which is preferably selected from luminescent dyes, thin-layer pigments, liquid crystal polymers, laser-markable substances and dyes.

With the help of rasterized offset printing plates, apart from different matting levels and finely resolved matt structures, additional Security features are generated, namely the finest point and line lenses. Essential here is the appropriate distance between the offset ink lines. In offset printing ink areas, the UV varnish will repel completely, while in areas outside the offset ink, it will completely wet out. In these areas, the ejected UV varnish accumulates, whereby it comes at the appropriate screening for the formation of lenses from UV high gloss varnish.

In a further embodiment, the UV high gloss lacquer is antimicrobial.

The present invention makes it possible to provide value documents of any kind with matt coatings that do not matte exactly in the field of anti-counterfeiting agents, but have glossy areas. The invention is particularly advantageous for equipping banknotes, in particular banknotes with polymer-based or film-composite banknotes, with a heavily matted coating and with a non-matted coating in the area of anti-counterfeiting agents, such as holographic structures and windows.

Claims (17)

1. A value document (1), such as a banknote or an identity document, having a flat substrate (2), being equipped on at least one surface (4, 4') of the substrate (2) with at least one falsification-protection means (10, 12) and having at least on the surface equipped with the falsification-protection means a coating (14, 14') with matte regions (18, 18') and non-matte regions (19, 19'), wherein the non-matte regions cover at least the falsification-protection means (10, 12) and the matte regions cover at least portions of the regions of the surface (4, 4') that are free of falsification-protection means, wherein the coating (14, 14') has a first layer (15, 15') with gaps (16, 16') and a continuous second layer (17, 17') of radiation-curing lacquer, wherein the continuous second layer (17, 17') is applied directly on the non-continuous first layer (15, 15'), and wherein the gaps (16, 16') of the non-continuous first layer (15, 15') define the non-matte regions (19, 19') of the coating (14, 14'), while the remaining regions of the coating (14, 14') define the matte regions (18, 18'), characterized in that the first layer (15, 15') consists of a hard-to-wet composition.
2. The value document (1) according to claim 1, characterized in that the hard-to-wet composition is an offset printing ink or a water-based lacquer that can be processed in flexographic printing.
3. The value document (1) according to claim 1 or 2, characterized in that the radiation-curing high gloss lacquer is a UV lacquer.
4. The value document (1) according to any of the claims 1 to 3, characterized in that the matte regions (18, 18') have a glossiness value of below 15% at 60° glancing angle, and the non-matte regions (19, 19') have a glossiness value of at least 15% at 60° glancing angle.
5. The value document (1) according to any of the claims 1 to 4, characterized in that the matte regions (18, 18') have different glossiness values.
6. The value document (1) according to any of the claims 1 to 5, characterized in that the different glossiness values are configured as a gradation between matte and glossy regions.
7. The value document (1) according to any of the claims 1 to 6, characterized in that the hard-to-wet composition and/ or the radiation-curing lacquer are carriers of additional falsification-protection features, preferably of luminescent substances, thin-layer pigments, liquid crystal polymers, laser-markable substances or dyes, which preferably visually have no color of their own.
8. The value document (1) according to any of the claims 1 to 7, characterized in that the substrate (2) consists of paper, of a plastic material or of a composite material.
9. The value document (1) according to any of the claims 1 to 8, characterized in that the falsification-protection means (10, 12) is a transparent or metalized hologram or a hole completely or partly penetrating the substrate (2).
10. The value document (1) according to any of the claims 1 to 9, characterized in that the value document is a banknote, preferably a banknote of cotton or on the basis of a plastic foil, also referred to as polymer substrate.
11. A value-document sheet or a value-document continuous material, characterized in that the sheet or the continuous material have a plurality of value documents (1) according to any of the claims 1 to 10.
12. A method for producing a value document (1), such as a banknote or an identity document, characterized by the following subsequent steps of:

    a) supplying a flat value-document substrate (2) with two surfaces (4, 4'),

    b) equipping at least one of the surfaces (4, 4') of the substrate (2) with at least one falsification-protection means (10, 12),

    c) applying a first layer (15, 15') of a hard-to-wet composition to at least one surface (4, 4') of the substrate (2) to at least a portion of the regions that were not equipped with the falsification-protection means (10, 12), so that the first layer (15, 15') has gaps (16, 16') at least in the region of the falsification-protection means (10, 12),

    d) partly, but not completely drying the first layer (15, 15') of the hard-to-wet composition,

    e) applying a second layer (17, 17') of a radiation-curing lacquer over the complete surface on the partly dried first layer (15, 15') of the hard-to-wet composition,

    f) radiation curing the second layer (17, 17'), wherein from the first layer (15, 15') and the second layer (17, 17') there results the coating (14, 14') which has matte regions (18, 18') in the places in which the second layer (17, 17') touches the first layer (15, 15'), and non-matte regions (19, 19') in places in which the first layer (15, 15') has gaps (16, 16'), and

    g) if applicable, completely drying the first layer (15, 15').
13. The method according to claim 12, characterized in that the application of the first layer (15, 15') in step c) takes place in an offset printing process.
14. The method according to claim 12 or 13, characterized in that the application of the second layer (17, 17') in step e) takes place in flexographic printing.
15. The method according to at least one of the claims 12 to 14, characterized in that the steps c) to e) are carried out in-line.
16. The method according to at least one of the claims 12 to 15, characterized in that the partial drying of the first layer (15, 15') in step d) and, if applicable, in step g) takes place exclusively through evaporation or penetration of liquid components of the hard-to-wet composition on the transport path in a printing machine and/ or finally dries through oxidative drying.
17. The method according to at least one of the claims 12 to 16, characterized in that a value-document sheet or a value-document continuous material according to claim 11 is produced.

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