EP1310381A2 - Weblike materials with surface structure, method of manufacture and use thereof - Google Patents

Abstract

A flat material comprises a completely or partially transferable surface structure. The surface structure is produced using a die and a light hardenable lacquer which is applied to a carrier substrate. The lacquer is pre-hardened to its gel point at the time of moulding, and after the surface structure is applied it is fully hardened. <??>A flat material comprises a completely or partially transferable surface structure. The surface structure is produced using a die and a light hardenable lacquer which is applied to a carrier substrate. The lacquer is pre-hardened to its gel point at the time of moulding, and after the surface structure is applied it is fully hardened. <??>The lacquer contains two photo-initiators which can be actuated at different wave lengths. The material is produced by forming a carrier substrate, coating it with a radiation hardenable lacquer, prehardening and final coating.

Description

The invention relates to web-like materials with a durable transferable or adherent surface structure, in particular a Diffraction structure, a process for their preparation and their use.

Web-shaped materials with surface structures, in particular Diffraction structures are used in various applications, for example, in the decoration, as components in particular optical Components in the technical field and in architecture, as Security elements for value documents and volumes, as Packaging elements and the like.

It is known to produce diffraction or diffraction structures, for example diffraction gratings and the like, by means of thermal molding in a particular thermoplastic carrier or lacquer layer by means of pressure and temperature.
Disadvantage of the surface structures thus produced is their low thermal, mechanical and chemical resistance by embossing in thermoplastic compositions. For applications as heat-sealing foils, for example packaging, blisters in the pharmaceutical industry or food packaging, the resistance of the surface structures, in particular against the processing pressure and the processing temperature in the heat sealing process and / or sterilization is usually not sufficient, so in this case the packaging process with the usual machines can be done, but strict restrictions in terms of pressure and temperature are respected or expensive ancillary equipment must be installed. Even with sealing processes against, for example, steel and also other plastics, the surface structures produced in the thermoplastic molding process prove to be too little resistant.

From WO 94/18609 is a method for simultaneous replication and direct application of a hologram or other diffraction grating a printing material, in particular on paper or cardboard, by means of a Surface relief structure bearing matrix known in which this structure in a radiation-curable lacquer layer is molded, wherein the curing of the Lacquer layer from the matrix side through the radiolucent Matrizenoberfläche takes place. Essentially, the curing of the the lacquer layer receiving the relief before removing the matrix from the paper or cardboard. According to this method, both self-adhesive products as It would also be possible to produce heat-sealing foils with diffraction structures.

Although diffraction structures are relatively inexpensive and can be conveniently replicated or applied to a substrate by means of this method, such a method or the product produced in this way is unsuitable for a number of applications.
For applications as a security element, the surface structures are too inaccurate produced by this method, since on the one hand the quartz glass embossing cylinder used in particular the surface is not precise and homogeneous enough to produce. The photopolymers used for the matrix are poorly resistant under the process conditions, whereby the life of the embossing tool is only low. The transfer of the surface structure in a lacquer layer, which is still fully cured while the die rests on the backing paper or cardboard, is also too precise, since when removing the die after curing, the lacquer layer and thus the surface structure, if necessary, mechanically not completely intact remains.
The usable coatings are very limited, since in practice only cationically curable UV coatings have been found to be suitable.

The object of the invention is therefore a carrier substrate with a diffraction or diffractive structure or a surface relief and a method and to provide a device for its production, in which on the one hand the Illustration of the diffraction structure independent of the type of carrier substrate with excellent precision, on the other hand, the carrier film and the thereon diffraction structure without interference with in the Packaging industry or in other technical areas, for example in the field of architecture in the manufacture of components, usual parameters can be processed without restriction, so an excellent Resistance of the diffraction structure is ensured.

The subject of the invention are therefore sheet-like materials with complete or partially transferable or fully liable or subject to limitations Surface structures, characterized in that the respective Transferable or adhesive surface structure by molding a Matrix in a radiation-curable applied to a carrier substrate Varnish which is pre-cured to the gel point at the time of the impression, followed, whereupon the radiation-curable varnish after application of the Surface structure is completely cured.

Another object of the invention is a process for the preparation web-shaped materials with a completely or partially transferable or completely or motionally limited surface structure, thereby characterized in that provided in a first step, a carrier substrate is in a second step, this carrier substrate in a Coating process is coated with a radiation-curable varnish, in a third step, this lacquer up to the gel point by stimulation with Radiation of a defined wavelength is pre-cured, and at the same time Impression of the surface structure is carried out in a fourth step the further curing (main hardening) of the radiation-curable varnish Excitation radiation of a pre-hardening step different Wavelength carried out, followed by a post-curing and optionally Further coating or finishing steps are performed.

In the text below, surface structures are understood to mean, in particular, diffraction or diffraction and relief structures understood.

Carrier foils, for example, are preferably flexible as the carrier substrate 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 μm, preferably 8 - 200 microns, more preferably 12 to 50 microns on.

The carrier substrate can on one or both sides with a hot or Be provided or cold seal adhesive or a self-adhesive coating the application of the surface structure and optionally after Performing further coating steps are provided with it.

The carrier substrate is used in a coating process such as a screen printing, gravure or flexographic printing with a radiation-curable varnish coated. The coating can be selective or over the entire area.

The radiation-curable lacquer may for example be a radiation-curable Paint system based on a polyester, an epoxy or polyurethane system 2 or more different, known in the art photoinitiators contains, at different wavelengths, a curing of the paint system to initiate to varying degrees. For example, a Activatable photoinitiator at a wavelength of 200 to 400 nm, the second photoinitiator then at a wavelength of 370 to 600 nm enableable. Between the activation wavelengths of the two photoinitiators If enough difference should be respected, so not too strong Excitation of the second photoinitiator takes place while the first photoinitiator is activated. The area where the second photoinitiator is excited should be lie in the transmission wavelength range of the carrier substrate used.

For the main hardening (activation of the second photoinitiator) can also Electron radiation can be used.

As a radiation-curable varnish, a water-thinnable varnish can also be used be used. Preference is given to polyester-based paint systems.

The impression of the surface structure, ie the diffraction, diffraction or relief structure, for example, at controlled temperature by means of a die or using a stamping die in the radiation-curable lacquer layer, which was pre-cured by activation of the first photoinitiator to the gel point and at the time of molding in this stage is located.
If a water-dilutable radiation-curable lacquer is used, it is optionally possible to precede predrying, for example by means of IR radiators.

The layer thickness of the applied radiation-curable varnish may vary depending on Requirements for the final product and thickness of the substrate vary and amounts generally between 0.5 and 50 μm, preferably between 2 and 10 μm, more preferably between 2 and 5 microns.

The impression of the surface structure is made register accurate to the coating the carrier substrate, with a tolerance of +/- 0.5 mm are maintained can. This is achieved by register control

The stamping mold can be transparent, it can be a welded, glued, be soldered or seamless metal sleeve or plastic sleeve. Prefers nickel sleeves are used. To make an exact impression of the To obtain surface structure, it is expedient to the embossing tool a temperature-controlled pneumatic and flow-cooled or to install heated clamping cylinder.

In this case, the carrier substrate is brought into contact with the temperature-controlled clamping cylinder, the embossing of the surface structure is preferably carried out only when the carrier substrate coated with the radiation-curable lacquer is in contact with the cylinder.
In this case, a precise control of the process parameters, such as pressure and in particular temperature in order to avoid too rapid or too slow a change in state of the paint layer.
The curing of the UV varnish and then a post-curing takes place.

The surface structure introduced into the radiation-curable lacquer draws due to great precision, in particular due to the hardening of the paint in two steps out. Furthermore, the structure has excellent durability, especially chemical, thermal and mechanical resistance. The If necessary, the product is therefore available after appropriate packaging Security element in data carriers, in particular value documents such as Badges, cards, banknotes or labels, seals and the like suitable, but also as packaging material in the pharmaceutical and Food industry, for example in the form of blister foils, for example Medicines, covers or packaging, for example in the Food industry as food film, for example for dairy products particularly suitable. Such products are also particularly suitable for decorative applications or optical elements, for example in the Architecture and the like.

The carrier substrate thus provided with a surface structure can subsequently provided with further layers, for example with additional paint, color or metallic layers or insulators, respectively may have different properties.

In this case, the application of the further layers either selectively, overlapping or congruent with the surface structure or even only in those areas that were left out by selective application of the structure respectively. It can also be made a full-surface coating.

For the production of so-called partial holograms can before application further layers, such as a metal layer, the embossed structure with a paint with the same or similar refractive index as that of partially used overprinted radiation-curable coating system. This selectively increases the surface texture in the overprinted areas invisible, so to speak deleted. The paint can be transparent or colorless or else luminescent, for example fluorescent or be phosphorescent.

For the production of partially metallized or with a varnish or lake layer Surface structures it recommends for the time being a paint application For example, for security applications in the form of a coding or a apply negative coding.

The application of the ink application can then register-controlled in one operation or in another printing unit insettergesteuert by any method, for example by gravure, flexographic, screen printing, digital printing and the like done to the embossing process. The color or lacquer used is soluble in a solvent, preferably water, but it is also possible to use a dye soluble in any solvent, for example in alcohol, esters and the like. The color or the colored lacquer can be customary compositions based on natural or artificial macromolecules. The soluble color may be pigmented or unpigmented. As pigments, all known pigments can be used. Particularly suitable are TiO ₂ , ZnS, kaolin and the like.

Subsequently, the printed carrier substrate is optionally treated to improve the adhesion of the subsequently applied layer by means of an in-line plasma (low pressure or Atmosphärenplasma-), corona or flame process. High-energy plasma, for example Aroder Ar / O ₂ plasma, cleans the surface of toning residues of the printing inks. The necessary sharp delimitation of the contours of the recesses, which is necessary for the necessary precision of the coding is achieved. At the same time, the surface is activated. In this case, terminal polar groups are generated on the surface. This improves the adhesion of metals and the like to the surface.

Optionally, simultaneously with 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 to 5 nm, preferably 0.2 nm to 2 nm, particularly preferably 0.2 to 1 nm.

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

Subsequently, other layers can be applied.

As such color or paint 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 Dekorationsals should also be a functional layer.

The layers to be printed may be pigmented or unpigmented. As pigments, it is possible to use all known pigments, for example titanium dioxide, zinc sulfide, kaolin, ATO, FTO, aluminum, chromium oxides and silicon oxides, as well as colored pigments. In this case, solvent-based coating systems and systems without solvents 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 also amorphous or crystalline ceramic pigments such as ITO and the like may be added. Furthermore, also doped or not doped semiconductors such as silicon, germanium or ion conductors such as amorphous or crystalline metal oxides or metal sulfides used as an additive become. Furthermore, for adjusting the electrical properties of Layer polar or partially polar compounds, such as surfactants or nonpolar Compounds such as silicone additives or hygroscopic or not hygroscopic salts are used or added.

To adjust the magnetic properties, paramagnetic, diamagnetic and also ferromagnetic materials, such as iron, nickel and Cobalt or its compounds or salts (for example, oxides or Sulfides) can be used.

The optical properties of the layer can be determined by visible dyes or pigments, luminescent dyes or pigments which are in the visible, fluoresce or phosphoresce in the UV range or in the IR range, Effect pigments, such as liquid crystals, pearlescent, bronzes and / or multilayer color change pigments and heat-sensitive colors or pigments influence. These can be used in all possible combinations. In addition, phosphorescent pigments alone or in Combination with other dyes and / or pigments are used.

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. Thus, 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 ink or lacquer 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 color or the colored lacquer can be customary 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 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 be able to produce codings in the form of characters and / or patterns of any possible type.

Furthermore, for example, insulator layers can be applied. When Isolators are, for example, organic substances and their derivatives and Compounds, for example paint and varnish systems, e.g. Epoxy, Polyester, Rosin, acrylate, alkyd, melamine, PVA, PVC, isocyanate, Urethane systems that can be radiation-curing, for example by Heat or UV radiation, suitable.

These layers can be prepared by known methods, for example by Vaporizing, sputtering, printing (eg gravure, flexo, screen, digital printing) and the like), spraying, electroplating and the like become. The thickness of the functional layer is 0.001 to 50 μm, preferably 0.1 to 20 microns.

Subsequently, the ink layer by a suitable solvent, the on the composition of the color layer is matched, removed. Is preferred the paint is water-soluble. Optionally, the replacement by mechanical action are supported.

Also, to further improve the dissolution of the covered ink layer full-surface or precise registration a thin pigmented layer of paint or a pure pigment layer are applied, the thickness of this layer is about 0.01 - 5 microns.

By removing the paint application with those above the paint job Regions of the functional layer, the desired end product is obtained.

In such a way by one or more repetition of one or more described method steps can be produced multilayer structures which are different in the superimposed layers 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 constructions, for example for security elements with several precise authenticity features manufacture.

The process steps can be repeated as often as desired, wherein For example, in full-surface application of a functional layer of Color order may be omitted, the inline plasma, corona or Flame treatment optionally with simultaneous application of a However, adhesion promoter can be advantageous.

But it can also, for example, in known Direct metallization process or in known multicolor printing processes apply additional layers.

Optionally, the thus produced coated film also by a protective lacquer layer are protected or, for example, by laminating or the like further refined.

Optionally, the product can be applied with a sealable adhesive, such as a hot or cold seal adhesive to the appropriate substrate, or embedded in paper for security papers by conventional methods, for example.
These sealants can be equipped with visible or visible in the UV light, fluorescent, phosphorescent or laser and IR radiation absorbing features to increase the security against counterfeiting. These features may also be present in the form of patterns or characters or show color effects, in principle any number of colors, preferably 1 to 10 colors or color mixtures, 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.

To produce the sheet-like materials according to the invention is in a first step provided a carrier substrate, in a second step radiation-curable paint applied, this paint to the gel point through Pre-hardened excitation with radiation of a defined wavelength and at the same time taking the impression of the surface structure, in one fourth step, the further curing (main hardening) of the radiation-curable Lacks by excitation with radiation to the pre-curing step different wavelength carried out, followed by a post-curing and optionally carried out further coating or finishing steps become.

The coating of the carrier substrate takes place in a coating process, For example, a screen flexo or gravure printing with a radiation-curable varnish. The coating can be selective or full-surface respectively.

For example, it is made of a heated temperature-controlled tub the radiation-curable varnish picked up and via a transfer cylinder and applied to the carrier substrate via a gravure cylinder. there the viscosity of the paint system becomes precise via the temperature setting controlled. Depending on the paint system used and the used carrier substrate, the paint application temperature is about 20 - 80 ° C, preferably 30 - 60 ° C, particularly preferably 40 - 50 ° C, where Lackund Tool temperature should each be at the same level.

Essential for a uniform coating order is that the to be applied lacquer always at exactly controlled temperature and constant purity and in a steady flow is picked up and applied. In particular, it is also a so-called. Avoid foaming of the varnish before or during application.

When using a water-borne radiation-curable varnish can before the hardening step to the gel point, a preheating step by a Radiation source, for example, an IR emitter are connected upstream.

The lamps are selected so that a selective excitation of the photoinitiators takes place.
For example, Hg lamps, Hg lamps doped in the long-wave range, especially Ga, Fe, Ga / Pb-doped Hg lamps, in the visible light range fluorescent tubes and the like are suitable for excitation in the short-wave range. In particular, the main curing can also be done by electron beam curing.

The energy of the UV lamp, which is used to cure to the gel point, can be controlled by the radiator parameters, but also by an upstream aperture.
Since only small amounts of UV light are necessary for precuring to the gel point, the use of a cooled diaphragm for metering the radiation is recommended.
Pre-curing is carried out in contact with a temperature-controlled roller for more precise control of the process speed.

Advantageously, the main hardening process is carried out to improve the uniformity and increase the production speed with 2 or more radiation sources (eg UV lamps) or, if curing in the visible light range, with 2 or more fluorescent tubes positioned so that the maximum light output through the film on the die falls.
Preferably, unfocused lamps are used with parabolic or open space reflectors.

The power of the radiation source used for curing to the gel point is about 80 to 240 W / cm, preferably 100 to 180 W / cm, the Power of the radiation sources used for the main hardening, is about 160 to 400 W / cm, preferably 200 to 240 W / cm.

Optionally, a subsequent hardening with corresponding radiation sources can then also be carried out, the power of which corresponds approximately to the power of the radiation sources used for hardening up to the gel point. The post cure is again in contact with a temperature controlled roll.
By closely controlling the postcure process, the properties of the product can be controlled, particularly with regard to adhesiveness and release, as well as chemical resistance. With far-reaching postcuring the chemical resistance is significantly improved, with less postcuring the release capability of the product is improved.

To ensure that during the hardening steps, so if necessary Pre-cure, cure to gel point, cure and post-cure certain wavelength range is maintained in the process, it is recommended the spectral composition of the lamps and the Intensity distribution with a corresponding inline spectrometer too monitor and thereby optionally the performance of the curing radiation to regulate.

The impression of the surface structure is made by a stamping die in the bis to the gel point precured lacquer layer. This stamping mold can be transparent It can be a welded, glued or soldered or seamless Be metal sleeve or plastic sleeve. Preference is given to nickel sleeves used. To obtain a precise embossing of the surface structure is it is convenient the stamping tool on a pneumatic and Temperature-cooled clamping cylinder to assemble.

After the main hardening or after a corresponding post-curing can Further coating and or finishing steps are performed. These steps can either be done directly in another step register-controlled subsequently to the embossing process. It However, it is also possible the further coating or finishing steps in one or more further operations, where it It is advantageous to carry out these steps in register and registration. This can then be advantageously carried out so that a register accurate Control of the already provided with the surface structure carrier web, for example, by insetter-controlled feeding takes place.

By matching the properties of the carrier film, in particular Roughness, surface energy and UV absorption, the paint properties, in particular the photoinitiator mixture used and the one used Curing lights make it possible to release the system without a release layer adjust. By using a primer layer based on a polyester-epoxy, Rosin, acrylate, alkyd, melamine, PVA, PVC, isocyanate or Urethane system and appropriate radiation source adjustment (such as distance the radiation sources, power and spectral range) may adhere the system be set.

With the method according to the invention surface structures of any Dimension to be molded, not greater than the layer thickness of the UV varnish are.

Another object of the invention is an apparatus for producing the sheet-like materials according to the invention according to the invention Process, characterized in that the paint applicator off a heated paint tray, a carry cylinder and a Gravure cylinder, the precure stage from a temperature controlled Chill roller with an associated radiation source for precuring, the embossing unit from a temperature-controlled embossing cylinder, the two or several radiation sources are assigned to the main hardening, and the Post-curing stage of a temperature-controlled cooling roller, at least a radiation source is assigned for postcuring, and consists of Tiefdruckwerk and a drying station consists.

In Fig. 1, a variant of such a device is shown. In this 1, the carrier substrate, 2 the heated paint pan, the contains radiation-curable varnish, 3 the dip cylinder, 4 den Carrying cylinder, 5 the gravure cylinder, 6 a squeegee, 7 the Radiation source with which the paint is pre-cured to the gel point, 6a a cooled aperture, 8 the temperature controlled chill roll, 9a and 9b the Radiation sources for the main hardening, 10 the embossing cylinder, 11 the Radiation source for post curing, 12 the temperature controlled chill roll, 13 a gravure printing unit and 14 a drying station.

As already mentioned, it is necessary for uniform application of the varnish that this is kept at constantly precisely controlled temperature and under uniform supply and purity, and in particular also the so-called foaming of the varnish is prevented.
This can be achieved in particular by a special embodiment of the paint applicator, in particular the paint tray.

The paint pan 2, as shown in Fig. 2, consists of a Outer trough 21 and an inner tub 22 with a return plate 22a. 23 means the inlet of the radiation-curable varnish from a reservoir 23 a via a pump 23 b and a filter 23 c, 24 means the outflow of radiation-curable varnish from the outer tub 22 in the reservoir. 3 means the dip cylinder and 4 the transfer cylinder. 25 means one Distribution tunnel for the radiation-curable lacquer, 26 the distributor plate of the Distributor tunnel.

From a reservoir 23 a, which is preferably designed double-walled and is heated to a corresponding temperature of the radiation-curable Adjusting paint is through a pump 23 b and a fine filter 23 c of the radiation-curable lacquer in the heated inner tub 22 of the paint pan. 2 promoted. In the inner tub, the radiation-curable lacquer is over a Distributor tunnel 25 and the distributor plate 26, which arranged with regularly Openings is evenly distributed. The inner tub has at the inner surface of the shape of an approximately half-cylinder, this surface is dimensioned so that the dip cylinder 2 in a defined constant Distance to the inner surface of the paint pan can intervene. Depending on the height of the Filling in the inner tub 22 of the paint pan engages the dip cylinder with about 1 / 3-1 / 2 of its circumference in the conveyed into the inner tub radiation-curable varnish. The heated inner tub is doing so dimensioned that they are heated on the from the outflow 24 of the surrounding Outside trough facing away on the dimension of a half-cylinder, however, its shape is essentially continuing return plate up to a height of at least half the diameter up to about 2/3 of the Diameter of the immersion cylinder has.

The dip cylinder now takes the radiation curable paint from the Inner pan of the paint pan and transfers it to the transfer cylinder. It now runs the excess paint, not from the carry cylinder is taken over the outside of the inner tub in the outer tub 21 back. Likewise (not shown in FIG Doctor blade 6 (shown in Fig.1) not applied to the gravure cylinder paint back to the outer tub.

Due to the orientation of the outer tub not plan in a plane but with a slight slope of the drain facing away from the side of the paint pan to the side on which the drain is located, the collected in the outer tub 21 paint from the entire Lackauftragswerk back into the reservoir 23a led. In the inner tub so there is always only from the reservoir under a defined temperature and with the pump 23 b defined inflow rate introduced paint.
By avoiding the return of paint not applied via the following cylinders and the squeegee to the inner sump, the temperature of the lacquer in the inner sump is kept correctly constant and also a so-called foaming of the lacquer by the introduction of air is avoided. Further, the temperature of the paint in the inner tub is constantly controlled by a temperature sensor (not shown in Fig.2)
The coating application can therefore be carried out with excellent uniformity under defined conditions.

All other provided in the device cylinders and rollers are in Dependence on the paint system used in each case an exact Subjected to temperature control.

The temperature-controlled embossing cylinder are two or more Radiation sources assigned to the main hardening, wherein the embossing process in the pre-cured to the gel point lacquer simultaneously with the main hardening he follows.

It is also possible in the device after the main hardening process optionally radiation sources for post-curing, or before the first Hardening stage (up to the gel point) Radiation sources for preheating (Especially when using a water-containing radiation-curable Provide varnish.

The planned gravure printing unit and the subsequent drying station can according to the usual manner according to the prior art be executed.

Example 1:

26,5% Polyesteracrylat

6,6% Epoxynovolackacrylat in Trimethylolpropantriacrylat/Hydroxyetyhlmetacrylat

26,5% hexafunktionelles atiphatisches Urethanacrylat

5,31% Mischung aus Pentaerythritoltri- und tetracrylat

21.2% Trimethylethylolpropantriacrylat

6,6% tertiäres Amin

6,9% Darocure (Initiator für den Kurzwelligen UV-Bereich)

0,2 % BAPO (Initiator für den kurzwelligen UV-Bereich)

In a double-walled storage vessel, a radiation-curable varnish of the following composition is provided:

26.5% polyester acrylate

6.6% Epoxynovolackacrylat in trimethylolpropane triacrylate / Hydroxyetyhlmetacrylat

26.5% hexafunctional atiphatic urethane acrylate

5.31% mixture of pentaerythritol tri- and tetracrylate

21.2% trimethylethylolpropane triacrylate

6.6% tertiary amine

6.9% Darocure (initiator for the short-wave UV range)

0.2% BAPO (initiator for the short-wave UV range)

The paint is brought to a temperature of 50 ° C and conveyed by a pump in the heated inner tub of the paint pan. About the dip cylinder, the transfer cylinder and the gravure cylinder and the doctor associated therewith, the paint is applied to the web. Subsequently, the pre-curing of the paint is carried out to the gel point at a temperature of 60 ° C by means of a Hg radiation source with upstream cooled (to 60 ° C) aperture. The embossing of the arbitrary surface structure is then carried out on an embossing cylinder with simultaneous hardening with 2 Hg / Ga radiation sources at a temperature of 70 ° C. For complete curing, the web is passed over a temperature-controlled cylinder using a Hg radiation source.
Subsequently, the material web thus provided with a surface structure can be guided into a conventional gravure printing unit and a subsequent drying station.

Claims (14)

Web-shaped materials with a completely or partially transferable or completely or limited by motive adhering surface structure, characterized in that the respective transferable or adhering surface structure by molding a die in a applied to a support substrate radiation-curable varnish, which is pre-cured at the time of molding to the gel point, whereupon the radiation-curable lacquer is completely cured after application of the surface structure. Web-shaped materials according to claim 1, characterized in that after curing of the surface structure, further coating and refining steps are carried out. Web-shaped materials according to one of claims 1 or 2, characterized in that the radiation-curable lacquer contains two photoinitiators which can be activated at different wavelengths. A process for producing sheet-like materials having a completely or partially transferable or completely or motif-adherent surface structure, characterized in that a carrier substrate is provided in a first step, in a second step this carrier substrate is coated in a gravure printing process with a radiation-curable lacquer, in a third Step this paint is precured to the gel point by excitation with radiation of a defined wavelength, in a fourth step, the molding of the surface structure and at the same time the further curing of the radiation-curable paint by excitation with radiation of a pre-curing step different wavelength is performed, followed by a post-curing and optionally further Coating or refining steps are performed. A method according to claim 4, characterized in that the coating of the carrier substrate with the radiation-curable lacquer takes place in a gravure printing method, wherein the radiation-curable lacquer is taken from a heated paint pan and applied to the carrier substrate at a defined temperature via a transfer cylinder and a gravure cylinder. Method according to one of claims 4 or 5, characterized in that the radiation-curable varnish used contains 2 photoinitiators which can initiate curing of the paint system to varying degrees at different wavelengths. Method according to one of claims 4 to 6, characterized in that the main hardening process is carried out by at least 2 radiation sources, which are positioned so that the maximum light output falls through the carrier substrate on the die or embossing mold. Method according to one of claims 4 to 7, characterized in that a pre-curing and a post-curing is performed. Method according to one of claims 4 to 8, characterized in that the embossing process is carried out at a defined temperature at the time at which the carrier substrate coated with a radiation-curable lacquer is in contact with a temperature-controlled clamping cylinder. Method according to one of claims 4 to 9, characterized in that the further coating and finishing steps are carried out in a subsequent operation. Method according to one of claims 4 to 10, characterized in that the main hardening is effected by electron radiation. Apparatus for carrying out the method according to any one of claims 4 to 11, characterized in that the paint applicator consists of a heated paint pan, a transfer cylinder and a gravure cylinder, the precure stage consists of a temperature-controlled cooling roller with its associated radiation source for precuring, the embossing of a temperature controlled Embossing cylinder, which are assigned to two or more radiation sources for main hardening, and the post-curing stage of a temperature-controlled cooling roller, which is associated with at least one radiation source for post-curing, and consists of a gravure printing unit and a drying station. Apparatus according to claim 12, characterized in that the heated paint pan consists of an inner and an outer tub, wherein the inner tub has an inner surface substantially in the form of a half cylinder with a one-sided this form continuing return plate, which at least until half to 2 / 3 of the circumference of the immersion cylinder engaging in the inner trough ranges and the outer trough is inclined in the direction of the side facing away from the drain to that side on which the drain faces. Use of the sheet-like materials according to claims 1 to 3 as security elements in data carriers, in particular Value documents, such as identity cards, cards, banknotes, as components in architecture and in other technical areas and as Packaging materials in the pharmaceutical or Food industry.

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