EP1318016A1 - Method for superposing several layers printed in register, products printed with this method and their application - Google Patents

Abstract

The web of material (1) already possessing a printed layer with register-marks and control lines is measured for length by means of a measure (2) between two or more register marks. The web of material is set at the required register length between two or more pulley-groups (4,4a). The web is controlled especially by a register control by means of a register roller (6) in front of a first printer (7).

Description

The invention relates to a method for producing register accurate printed multilayer structures in various printing units, as well as after products made by this process.

In the production of several functional layers by means of different Printing process may be required to interrupt the printing process and the already printed web then into another printing unit to bring in additional layers on the already printed web applied. However, these additional layers must be precisely in the Longitudinal and side registers are applied.

In EP-A 504 486 a method for accurate register, multicolor printing of a web is described, in which the web is passed through a plurality of printing units, each printing cylinder imprints a partial print image in a particular ink, wherein on the web markings (marks and Lines) are printed, which are optically scanned for detecting the relative pressure position of the printing cylinder to the web transversely to the transport direction by means of sensors, in which case the respective printing cylinder is displaced accordingly.
If the printing process has to be interrupted, the procedure is not sufficient. Since the complexity of the process steps due to the ever-increasing required precision and properties of the webs, especially in security elements, increasing more often, a printing process is often no longer sufficient on presses with 10 commissioned works.

The object of the invention was therefore to provide a method in which it is possible on a provided unprinted substrate printing layers in to apply the highest precision and then to these layers in a separate operation both in the longitudinal and in the transverse direction Register accurate within the smallest tolerances apply more layers.

The invention therefore provides a process for the production of register-accurate printed multilayered structures also in a plurality of independent printing operations on an uncoated or already coated or printed web with register marks and control lines, which is characterized in that already with a defined printed layer with register marks and Control lines provided material web is measured over an upstream measuring device between two or more register marks in length and between two or more controlled train groups is set to the necessary register length,
Subsequently, the material web is controlled in register by a control circuit, in particular a register controller via a register roller in front of the first printing unit,
wherein the side register is precontrolled via a path control and controlled by a pivoting frame,
whereupon the material web is printed on the material web with one or more functional or decorative layers in registration and registration with the possibly already existing coating.

The already printed material web has register marks and control lines, the inline to determine the exact register distances by means of optical Sensors are measured.

Is the distance between the register marks larger than the required one? Register length, for example, by heating by means of an IR dryer, a heat roller or a convection dryer the printed Material web pre-shrunk to the required length, is the distance between the register marks smaller than the required register length becomes the printed web suitably between two draw groups or several times in succession with several train groups on the corresponding Length prestretched.

Before the first printing unit is then the so on the appropriate Length adjusted material web controlled by a register roller. in the Side register is the correct control via a train control or via a swing frame, as well as a sliding cylinder. Subsequently, the printing process with longitudinal and side register control carried out.

This method makes it possible to register several layers in register, both in the longitudinal and in the side register and both on the front and also on the back if necessary using a turning station within the smallest tolerances apply. Further, when using an additional laminating two or more printed films laminated in register.

As a material web, for example, carrier films, preferably flexible Plastic films, for example, from Pl, PP, MOPP, PE, PPS, PEEK, PEK, PEI, PSU, PAEK, LCP, PEN, PBT, PET, PA, PC, COC, POM, ABS, PVC in question. The carrier films preferably have a thickness of 5 - 700 microns, preferably 8-200 μm, more preferably 12-50 μm.

Furthermore, metal foils, for example Al, Cu, Sn, Ni, Fe or stainless steel foils having a thickness of 5-200 μm, preferably 10 to 80 μm, particularly preferably 20-50 μm, may also serve as the carrier substrate. The films can also be surface-treated, coated or laminated, for example with plastics, or painted.
Further, as carrier substrates also paper or composites with paper, for example, composites with plastics with a grammage 20-500 g / m ^2, preferably 40-200 g / m ^2. be used.

Further, as carrier substrates, woven or nonwoven fabrics, such as continuous fiber fabrics or nonwovens, staple fiber fabrics or nonwovens, and the like, which may optionally be needled or calendered, may be used. Preferably, such fabrics or webs of plastics, such as PP, PET, PA, PPS and the like, but it can also be woven or nonwovens of natural, optionally treated fibers, such as viscose fiber fabric or nonwoven fabrics used. The fabrics or nonwovens used have a basis weight of about 20 g / m ² to 500 g / m ² .

The already existing on the carrier substrate layer can be a color or Lacquer layer, a surface-structured layer, a metal layer, a partially (positive or negative) metallized layer, a conductive layer, a magnetic layer and the like. These layers can both be applied over the entire surface as well as partially.

The application of the layer may be by any method, for example, by gravure printing, flexographic printing, screen printing, offset, digital printing (Inkjet, dry and liquid toner) and the like be done, wherein the Determining the register length corresponding register marks for the Longitudinal registers and control lines for the page register were brought along.

These register marks are then inline by means of optical sensors measured and those already provided with one or more layers Material web introduced via a register roller in the first printing unit and printed with one or more additional layers.

The further layer can in turn be a paint or varnish layer, a surface-structured layer, a metal layer, a conductive layer, a magnetic layer and the like. These layers can turn both full surface and partially applied.

The existing on the web (s) printed (s) layer (s) or the layers applied in the further separate steps can correspond to each other or be different and become the following described.

As color or lacquer layers can each have a variety of Compositions are used. The composition of the individual Layers can vary in particular according to their task, so whether the individual layers serve only decoration purposes or one functional layer or whether the layer is both a Decoration as well as a functional layer should be.

The layers to be printed may be pigmented or unpigmented. As the pigments, there may be used any known pigments, for example, inorganic-based pigments such as titanium dioxide, zinc sulfide, kaolin, ITO, ATO, FTO, aluminum, chromium and silicon oxides, or organic-based pigments such as phthalocyanine blue, i-indolidine yellow, dioxazine violet and the like It is also possible to use colored and / or encapsulated pigments in chemically, physically or reactively drying binder systems. Examples of suitable dyes are 1,1- or 1,2-chromium-cobalt complexes.
Solvent-containing paint and / or paint systems, aqueous and solvent-free paint systems can be used.
Suitable binders are various natural or synthetic binders.

For example, the functional layers may have certain electrical, magnetic, chemical, physical and also optical properties exhibit.

For adjusting electrical properties, such as conductivity can For example, graphite, carbon black, conductive organic or inorganic Polymers, metal pigments (for example copper, aluminum, silver, gold, Iron, chromium and the like), metal alloys such as copper-zinc or copper-aluminum or amorphous or crystalline ceramic pigments such as ITO, FTO, ATO and the like may be added. Furthermore, can also be doped or undoped semiconductors such as silicon, germanium, Gallium arsenide, arsenic or ionic conductors such as amorphous or crystalline metal oxides or metal sulfides are used as an additive. Further, for adjustment the electrical properties of the layer polar or partially polar Compounds such as surfactants or nonpolar compounds such as silicone additives or hygroscopic or non-hygroscopic salts used or be added. Similarly, intrinsically conductive organic polymers such as polyaniline, polyacetylene, polyethylenedioxythiophene and / or Polystyrene sulfonate can be added.

To adjust the magnetic properties, paramagnetic, diamagnetic and also ferromagnetic substances, such as iron, nickel, barium, and cobalt or their compounds or salts (for example, oxides or Sulfides) can be used. Particularly suitable are Fe (II) and Fe (III) oxides, Barium or cobalt ferrites, rare earths and the like.

The optical properties of the layer can be defined by visible colors or pigments, luminescent dyes or pigments which are in the visible, fluoresce or phosphoresce in the UV range or in the IR range, heat-sensitive inks or pigments, effect pigments, such as liquid crystals, Affect pearlescent, bronzes and / or multilayer color change pigments. These can be used in all possible combinations.

Various properties can also be combined by adding various additives mentioned above. Thus, it is possible to use colored and / or conductive magnetic pigments. All mentioned conductive additives can be used.
Especially for the dyeing of magnetic pigments it is possible to use all known soluble and non-soluble dyes or pigments. For example, a brown magnetic ink can be adjusted to metallic, for example silvery, by adding metals in their color shade.

For printing soluble layers, the paint or varnish used may be soluble in a solvent, preferably water, but a dye soluble in any solvent, for example in alcohol, esters and the like may also be used. The paint or lacquer may be conventional compositions based on natural or artificial macromolecules. The color may be pigmented or unpigmented. As pigments, all known pigments can be used. Particularly suitable are TiO ₂ , ZnS, kaolin and the like.
If a soluble (partial) color layer is used, it may optionally be removed after application of another layer in the process according to the invention by a suitable solvent adapted to the composition of the color layer in order to produce codes in the form of characters and / or patterns of any possible kind to be able to, as described for example in DE 101 43 523.

But it can also be applied intermediate layers of a metal, a metal compound, an alloy or an insulator. As the metal layer, layers of Al, Cu, Fe, Ag, Au, Cr, Ni, Zn and the like are suitable. Examples of suitable metal compounds are oxides or sulfides of metals, in particular TiO ₂ , Cr oxides, ZnS, ITO, ATO, FTO, ZnO, Al ₂ O ₃ or silicon oxides. Suitable alloys are, for example, Cu-Al alloys, Cu-Zn alloys and the like. As insulators, for example, organic substances and their derivatives and compounds, such as paint and lacquer systems, such as epoxy, polyester, rosin, acrylate, alkyd, melamine, PVA, PVC, isocyanate, urethane, the radiation-curing can be, for example, by heat or UV or electron radiation suitable.

All dyes and pigments can be used alone or in combination with different natural or synthetic binders, e.g. natural oils and resins, such as phenolformaldehyde, urea, melamine, ketone, Use aldehyde, epoxy, polyterpene resins. As an additional binder For example, polyesters, polyvinyl alcohols, polyvinyl acetates, ethers, propionates and chlorides, poly (methyl) acrylates, polystyrenes, olefins, Nitrocellulose, polyisocyanate, urethane systems and others.

All of these layers can be prepared by known methods, for example by Vaporizing, sputtering, printing (gravure, flexo, screen, digital offset printing and the like), spraying, electroplating and the like.

Before application of these layers, the material web can be conveyed by means of an in-line plasma (Low pressure or atmospheric plasma), corona or Flame process to be treated. The surface is activated, whereby terminal polar groups are generated on the surface and the Surface is cleaned. This will increase the adhesion of metals, paints and Lacquers on the surface improved.

Optionally, simultaneously with or after the application of the plasma or corona or flame treatment, a thin metal or metal oxide layer can be applied as adhesion promoter, for example by sputtering or vapor deposition. Particularly suitable are Cr, Al, Ag, Ti, Cu, TiO ₂ , Si oxides or chromium oxides. This adhesion promoter layer generally has a thickness of 0.1 nm-5 nm, preferably 0.2 nm-2 nm, particularly preferably 0.2 to 1.0 nm

As a result, the liability of the partially or fully applied optionally structured functional layer further improved. This is Prerequisite for the production of functional layers with high Precision and good adhesion.

However, it is also possible for a layer which has or has a surface structure, for example a diffraction structure or a surface relief, to be applied, wherein this structure is preferably embossed into a radiation-curable lacquer layer.
Furthermore, further layers can be applied by known methods, for example direct metallization methods, partial metallization methods register-accurate, over the entire area or partially.

These layers can each have encodings or negative encodings in them Shape of patterns, characters, micro and macrolines, letters, images, mathematically definable line elements, reliefs, guilloches as well have machine-readable elements and the like.

The superimposed layers can be different Have properties. It is possible by combining different properties of the individual layers, for example Layers with different conductivity, magnetizability, optical Properties, absorption behavior and the like, for example To produce security elements with several precise authenticity features.

Optionally, the coated material web thus produced can also be protected by a protective lacquer layer or for example by Laminating or the like can be further refined.

The material webs produced according to the invention are due to the high Precision of the dimensions of the applied layers in particular optionally after cutting into strips or bands, for example with a width of 0.2 to 75 mm, as security elements, in particular in Value documents and data carriers, such as banknotes, securities, Identification documents, cards and the like used or as Security elements or security labels in packaging, textiles, Sealing and the like and used as tearing threads.

Due to the excellent precision and the possibility of after inventive method also multilayer, very thin films To produce, the products of the invention are in particular also for Embedding in banknotes and the like suitable. This is the printed Material web initially register accurate according to the applied layers Cut into ribbons, strips or other formats and then embedded or applied.

Optionally, the product may be coated with a sealable adhesive, For example, a hot or cold seal adhesive or a self-adhesive the corresponding carrier material are applied, or for example at papermaking for security papers by conventional methods in the Be embedded paper. If necessary, the seal adhesives can also be used be applied in the described method according to the invention.

These sealants can be visible with visible or in UV light, fluorescent, phosphorescent or laser and IR radiation absorbent and reflective features to increase the Counterfeit security be equipped. These features can also be in shape of patterns or characters or show color effects, where any number of colors or color mixtures, preferably 1 to 12 colors or Color mixtures printed in register are possible.

The carrier substrate may be used after one-sided coating after application be removed or left on the product. In this case, the carrier film optionally specially equipped on the uncoated side be scratch resistant, antistatic and the like. The same applies to a possible lacquer layer on the carrier substrate.

In Fig. 1 the inventive method is shown.

1 means the material web coming from the mother roll, 2 the Length measuring device (sensors), 3 a dryer, 4 the first train group, 4a the second train group, 5 the register scan and length control, 6 the Register roller in front of the first printing unit and 7 the printing unit.

The parent role provided with register marks and control lines provided and already arbitrarily printed web is over a Guide roller by the length measuring device, preferably from 2 Sensors consists, led.

Depending on the result of the length measurement, i. the evaluation of the distance between two or more register marks, then the Material web either by shrinking by, for example, heating or by stretching between two or more train groups on the corresponding register length set.

The control of the distance between the register marks takes place via a control loop, in particular a register controller, which determines the distance scans and controls between the register marks and a corresponding Control of the two train groups triggers.

Subsequently, the set with a control loop, such as a register controller, set to the correct register length material web is controlled via a register roller in the printing unit.
The correct control of the side register is carried out simultaneously via a web control and / or a swing frame, the fine control is effected by lateral displacement of the printing cylinder.

In the printing unit is then the so-called already printed Material web printed register and register.

In this way, one or more times already printed Material webs in different printing units, each optionally with Interruption of the operation simply and inexpensively register and exact registration also on front and back as often as desired with different or similar layers are printed. Further, when using Another Kaschierwerks two or more printed film webs in register also inline be laminated.

Another object of the invention are according to the invention Processed products.

Particularly good results are thereby when using a Carrier substrate, such as a film, a paper and the like with achieved limited and reproducible shrinkage-expansion behavior.

An example of a process produced by the process according to the invention Product is shown in Fig. 2, with two initially separated with various layers of accurately printed material webs subsequently laminated in register.

Therein 1 is a hot-seal adhesive, 2 a PET film, 3 a primer, 4 a surface-structured layer, 5 a partial metallic layer, for example, an Al layer, 6 a magnetic layer, 7 an adhesive layer and FIGS. 8 a to 8 d show a fluorescent color layer with a color gradient.

Claims (10)

Process for the production of register-accurate printed multi-layered structures also in several independent printing processes on an already coated or printed web with register marks and control lines, characterized in that the possibly already provided with a defined printed layer with register marks and control lines web via an upstream measuring device between two or more register marks is measured lengthwise and is set to the necessary register length between two or more controlled train groups, then the web of a control loop, such as a control loop, in particular a register controller, is controlled in register via a register roller before the first printing unit, wherein the Side register via a path control pre-controlled and / or controlled by a swing frame, whereupon the material web with one or more functional n or decorative layers passerund register accurate to the existing coating on the web is printed. A method according to claim 1, characterized in that the determination of the necessary register length by inline measurement of the existing on the printed web register marks. Method according to one of claims 1 or 2, characterized in that the adjustment of the correct register length by shrinkage by means of a dryer or stretching between two or more Zuggruppen occurs. Method according to one of claims 1 to 3, characterized in that in the sequence a plurality of functional color layers and / or metallic layers and / or surface-structured layers and / or conductive and / or magnetic layers and / or optical layers in one operation or in different printing units be printed. Method according to one of claims 1 to 4, characterized in that the specified method steps are repeated one or more times for applying different layers. Method according to one of claims 1 to 5, characterized in that the layers on the front and on the back are optionally printed in register using a turning station. Method according to one of claims 1 to 6, characterized in that using a laminating two or more printed material webs are laminated register accurate. Products prepared in a process according to claims 1 to 7. Products according to claim 8, characterized in that the webs of material produced in a process according to claims 1 to 7 are subsequently cut register-accurate into strips, strips or other formats. Use of the products according to one of claims 8 or 9 as Security elements, in particular in value documents and Data carriers, such as banknotes, securities, Identification documents, cards and the like used or as Security elements or security labels in packaging, Textiles, seals and as a tear thread and the like.

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