EP2938496B1 - Method and device for cold stamping on three-dimensional articles - Google Patents

Description

The present invention relates to a method and an apparatus for cold stamping on three-dimensional objects, in particular on cylindrical, oval, rectangular, flat objects.

The hot stamping method is known for decorating paper, labels, plastic and glass packaging with decorative foils, in particular with metallized foils. Here, a transfer or embossing film (i.e. a plastic carrier film with picked up decoration material, in particular with a metal layer) is coated with a hot glue. In a hot stamping machine, the adhesive layer is activated with a stamp using pressure and temperature, so that there is adhesion between the metal layer and the printed article. The carrier film is then removed.

There is also the so-called cold embossing process (also known as cold foiling) for roll goods and sheet goods (paper, foils, labels). The adhesive is first applied to the article using a printing process (offset printing or flexographic printing). Then the film is laminated on and the adhesive layer is dried. As a result, the decoration material adheres to the pre-printed areas and the carrier film with the remaining, non-adhering decoration material is removed. An adhesive that cures under UV radiation (UV adhesive) is often used as the adhesive. The adhesive is then dried through the film by means of UV radiation.

The cold stamping process has a number of advantages over the hot stamping process. Since there is no need to heat the adhesive using an embossing stamp, there is no speed restriction. As a result, a cold stamping device can be integrated in a printing press; no separate production process is necessary. Finally, there are also lower tool costs because no stamping is necessary.

Cold stamping on three-dimensional objects such as glasses, bottles, jars, cans or tubes is not possible with the known methods. In the known methods, the material to be provided with the film and the transfer film have to be guided in parallel for a time after lamination in order to be able to cure the adhesive by exposure to UV radiation. However, three-dimensional objects are, for example, on a holding device such as one in the German utility model DE 20 2004 019 382 described holding mandrel pushed and rotated by this when printing at various workstations about the longitudinal axis. As a result, the object is accessible from all sides and it is possible to print the object all around.

The printing of three-dimensional objects often takes place on so-called rotary transfer machines or linear transfer machines, in which the object is printed with different colors at different workstations or the surface of the object is otherwise treated.

The French patent application FR 2 865 965 A1 relates to a method for decorating cylindrical container walls by hot marking transfer foils.

The U.S. patent application US 2010/0212821 A1 relates to a method for cold stamping on a substrate, to which an adhesive layer is first applied.

The international patent application WO 03/020519 A1 relates to a method for applying a layer of a transfer film to a substrate.

The present invention is therefore based on the object of enabling cold stamping on three-dimensional, in particular cylindrical, oval, rectangular, flat objects, in particular on rotary cycle machines or linear cycle machines, in which cold stamping is only part of the work steps carried out on the object. This object is achieved by a method according to claim 1 and by a device according to claim 11. Advantageous developments of the invention can be seen from the dependent claims.

In a method according to the invention for cold stamping on a three-dimensional object, the object is turned around an axis of rotation rotatably held by a holding device. In a first step, an adhesive is applied to the object at a first work station. In a second step, a transfer film is pressed onto the object by a pressing device at a second work station. At the same time, the adhesive is hardened at the second work station. According to the invention, the adhesive is a UV adhesive, the curing of the adhesive being carried out by irradiation with UV radiation.

As a result, the decoration material of the transfer film adheres to the areas on the object provided with adhesive. If the transfer film is then removed from the three-dimensional object after it has been pressed on, the decorative material remains at the desired locations on the object. At the points where no adhesive was applied to the object in the first step, the decorative material does not adhere to the object, but remains on the carrier film of the transfer film.

In a preferred embodiment, the transfer film has the carrier film and a decoration material which can be removed from the carrier film, the decoration material, starting from the carrier film, comprising a transparent release layer, an optional transparent protective lacquer layer, a decoration layer and at least one primer layer made of a thermoplastic adhesive which is in a temperature range of> 90 ° C can be activated.

The transfer film has, in particular on its side facing away from the carrier film, a primer layer made of a thermoplastic adhesive which, during the cold film transfer, acts as an adhesion promoter layer to form a cold adhesive which crosslinks under UV radiation acts on an object. It has surprisingly been found that a particularly strong connection between the decoration material and the object and / or the primer layer can be formed by a combination of a primer layer made of thermoplastic adhesive arranged on the decorative material with a cold adhesive which crosslinks on the object under UV radiation is. This is surprising since thermoplastic adhesives, also called hot melt adhesives, and cold adhesives, in particular adhesives that crosslink under UV radiation, are substances whose adhesive effects are based on completely different chemical-physical principles.

The decorative material that can be detached from the carrier film, starting from the carrier film, preferably has a transparent polymeric peeling layer which, in a temperature range from 15 ° C. to 35 ° C., has a peeling force of the decorative material from the carrier film in the range from 15 cN to 35 cN, in particular in the range from 20 cN to 30 cN. The details of the peel force relate to a film strip 15 cm wide.

In the case of a transfer film, the release force of the decoration material from the release layer or from the carrier film and the force for detaching areas from the decoration material under transfer conditions must be less than the adhesive force between the object and the decoration material, which is due to the type of cold adhesive used and its Affected with the object on the one hand and the primer layer on the other. Only then can the decoration material or areas of the decoration material detach from the carrier film and stick to the object during the transfer. Before the transfer, however, the release force of the release layer from the carrier film must be so high that safe handling of the transfer film is ensured without the decoration material detaching from the carrier film, for example when the transfer film is unwound from a supply roll and / or when the transfer film is being transported , if necessary via deflection devices, into a cold foil transfer unit. In order to be able to wind up and unwind the transfer film, it has proven particularly useful to provide a suitable non-stick layer on the side of the carrier film facing away from the decoration material.

The peel force indicates the force (usually in the force / length unit) to be used to separate two layers; there is a positive correlation between the peeling force of a first layer from a second layer and the adhesion between the first and the second layer. The determination of the required release force between the carrier film and the decorative material of the transfer film according to the invention was determined by FINAT test method No. 3 (FTM3, low speed release force). The peeling force has the unit N or cN, the force being determined independently of the path, but in relation to a 15 cm wide film strip.

In comparison to a conventional decoration material with a release layer based on wax or silicone, release forces from a carrier film were measured for a decoration material with a polymer release layer, which were up to 250%, in particular up to 150%, higher. However, the decoration material was still sufficiently removable and, in contrast to decoration materials of transfer foils, which have release layers based on wax or silicone, could be overprinted very well, with very good adhesion of the dried or hardened printing ink to the decoration material.

For the transfer film, it is particularly preferred if the release layer is free of wax and / or free of silicone. In particular, the transfer film does not have a conventional release layer based on wax or silicone, which has hitherto caused decorative materials of transfer films which have been provided with them to be used only to a limited extent or not at all with conventional printing inks, in particular UV-curing printing inks, UV-curing varnishes, hybrid inks or - paint, were printable.

The adhesion of printing inks to decorative material areas of the transfer film, which were transferred to the object by means of the method and the device according to the invention, was determined approximately 1 hour after printing using the following test at room temperature:
A test sample in the form of an object with the decoration material cold applied thereon and printing with decoration material at least on partial areas was arranged on a flat surface. A 13 cm to 16 cm long strip of Tesafilm 4104 was stuck on so that about 5 cm to 7 cm of the Tesafilm protruded from the edge of the object. The tape was then pressed on three or four times with the thumb and finally pulled off the test sample at an angle of> 90 °. The test is considered passed if 90% of the ink remains on the test sample or the test sample itself is torn.

Printing of a decoration material with conventional printing inks, especially with the UV-curing printing inks, UV-curing varnishes, hybrid inks or varnishes mentioned above, adhered excellently to the decoration material, so that the test was rated as very good.

The release layer preferably has a thickness in the range from 0.01 μm to 0.5 μm, preferably in the range from 0.01 μm to 0.3 μm, more preferably from 0.1 μm to 0.2 μm. This comparatively small thickness of the release layer allows the decorative material to be removed from the transfer film with sharp edges. The accuracy that can be achieved and the resolution that can be achieved in this way can correspond comparatively exactly to the layout of the cold adhesive layer applied partially, preferably on the object, without deviating significantly therefrom, thereby A high degree of register accuracy of the cold foil layout can be achieved with a possible existing print layout from conventional printing inks. In this edge-sharp partial detachment according to the invention, the small thickness of the detachment layer produces only very small and very few so-called flakes, i.e. small layer residues of the decoration material of the transfer film, which can be disruptive in subsequent process steps and / or can disrupt the visual appearance of the coated object. The comparatively small thickness of the release layer enables resolutions to be achieved which are below the resolution capacity of the human eye. Another advantage of a thin release layer is the only slight release force that has to be applied when the layers are severed during partial transfer.

It has proven useful if the at least one primer layer has a thickness in the range from 1 μm to 5 μm, in particular in the range from 1.5 μm to 3 μm.

Furthermore, the at least one primer layer can be colored and / or matted, for example to enhance an optical contrast to the object or to initiate the polymerization of the UV adhesive layer under the primer layer by means of a greater absorption possibility or also optical scattering capacity of the UV radiation to improve or accelerate. Matting is understood to mean the reduction in the transparency or radiation permeability of the primer layer.

It has also proven useful if the at least one primer layer, which is to adjoin the cold adhesive, has a surface roughness in the range from 100 nm to 180 nm, in particular in the range from 120 nm to 160 nm. The surface roughness is determined, among other things, by the application process and the formulation of the primer layer. It was found that a lower surface roughness, but surprisingly also a higher surface roughness of the primer layer, leads to a reduction in the achievable adhesion between a cold adhesive and the decoration material. The surface roughness of the primer layer was determined by means of interference microscopy.

Not only one, but also two or more primer layers can be present, which differ in their chemical and / or physical properties, on the one hand for optimal adhesion in the direction of the adjacent decorative layer (s) and on the other to achieve optimal adhesion in the direction of the UV cold glue coming into contact with the decoration material. The carrier film preferably has a thickness in the range from 7 μm to 23 μm. The carrier film is preferably formed from polyester, polyolefin, polyvinyl, polyimide or ABS. The use of carrier films made of PET, PC, PP, PE, PVC or PS is particularly preferred. In particular, a carrier film made of PET has proven itself.

The transfer film overall has a thickness in the range from 9 μm to 25 μm, in particular in the range from 13 μm to 16 μm.

It has proven effective if the decoration material has a protective lacquer layer. The protective lacquer layer in particular provides protection against mechanical and / or chemical stress on the decorative material on an object. The protective lacquer layer preferably has a thickness in the range from 0.8 μm to 3 μm, in particular from 0.9 μm to 1.3 μm, and can furthermore be crystal-clear, colorless or colored or at least partially colored. Dyes and / or pigments can be used for coloring. Pigments can also be used to matt the protective lacquer layer, i.e. to reduce the transparency or radiation permeability of the protective lacquer layer.

The decorative layer of the decorative material is preferably formed by a metallic layer or a dielectric layer. It has proven useful if the decorative layer has a thickness in the range from 8 nm to 500 nm. The metallic or dielectric layer can be colored by additional, in particular transparent or translucent, color layers. Alternatively, the decorative layer can also have only one or more, in particular transparent or translucent or opaque, color layers without a metallic or dielectric layer. The color layers can be applied in particular by means of printing processes. All common printing processes (for example screen printing, flexographic printing, offset printing, digital printing) can be used as printing processes for the color layer. As an alternative or in addition to metallic or dielectric layers or colored layers, the decorative layer can have a lacquer with embossed macroscopic, in particular refractive, or microscopic, in particular diffractive optic, relief structures. These relief structures can be, for example, refractive lens or prism structures or optically diffraction, ie diffractive Lattice structures such as a hologram, a KINEGRAM®. The relief structures can also be isotropic or anisotropically scattering matt structures or regularly or irregularly structured anti-reflection structures. Macroscopic relief structures have approximate sizes (structure period, structure depth) of approximately 1 µm to 1000 µm. Microscopic relief structures have approximate sizes (structure period, structure depth) from approximately 10 nm to approximately 100 µm.

The dielectric layer is in particular formed from at least one material from the group comprising metal oxide, polymer or lacquer. A dielectric layer made of HRI material (HRI = High Refractive Index), such as SiOx, MgO, TiO _x , Al ₂ O ₃ , ZnO, ZnS, has proven particularly useful. The variable x is preferably in the range from 0 to 3, ie x = 0, 1, 2, 3.

The decorative layer can in particular also be formed from an HRI material which is transparent in the UV wavelength range, such as CdSe, CeTe, Ge, HfO ₂ , PbTe, Si, Te, TiCl or ZnTe.

The metallic or dielectric layer can preferably serve as a reflection layer for the above-mentioned relief structures and, in particular, be applied directly to the relief structures, in particular be vapor-deposited and thus follow the surface shape of the molded-in relief structure.

The decorative layer can have the dielectric, metallic or color layers mentioned in each case over the entire surface and in a uniformly applied layer thickness. Alternatively, some or all of these dielectric, metallic or color layers can also be partially applied and in particular form a motif. The motif can be composed of partial areas of the individual layers, whereby the individual layers can be formed side by side and / or overlapping. In particular, it is possible to apply the individual layers in the form of a grid in order, for example, to use three or four colors (for example as a CMY or CMYK grid; C = cyan, M = magenta, Y = yellow / yellow, K = black / black) to obtain a true color image to create. The individual halftone dots of the color layers are next to and / or one above the other. The color layers can also be metallic and / or optically variable, i.e. angle-dependent, pigments or dyes included. The color layers can also contain fluorescent and / or phosphorescent dyes.

If the decorative layer has a motif, it is advantageous to apply the motif to the object in a desired position, in particular in a precise position. The position accuracy is also called register accuracy. For this purpose, the decorative layer preferably has register marks in its edge region, which can be read out optically by correspondingly arranged sensors. On the basis of the sensor measured values, the feeding or the positioning of the transfer film can be controlled, for example by means of servomotors, in such a way that a motif is positioned on the transfer film in register with a correspondingly adjusted position of the object and then the carrier film is pressed onto the object. The desired register accuracy is in particular ± 1 mm, preferably ± 0.5 mm, particularly preferably <= ± 0.3 mm.

In an alternative embodiment, the transfer film has a carrier film and an embossing lacquer layer, in particular a transparent embossing lacquer applied thereon, one or more of the above-mentioned relief structures being embossed into this embossing lacquer layer. The embossing lacquer layer with the relief structures is preferably an outer layer of the transfer film, the relief structures being embossed on the side of the embossing lacquer layer facing away from the carrier film. A very thin non-stick layer (thinner than 1 µm) can be applied to the embossing lacquer layer. In this alternative embodiment, there is no release layer between the embossing lacquer layer and the carrier film. The embossing lacquer layer is preferably a UV-hardened or electron-beam hardened lacquer layer.

Alternatively, the relief structures can also be embossed directly in the carrier film, without using an additional embossing lacquer layer. A very thin non-stick layer (thinner than 1 µm) can also be applied to the relief structures.

In this alternative embodiment, the object is held rotatably about an axis of rotation by the holding device. In a first step, as before, an adhesive is applied to the object at a first work station. In a second step, as before, a transfer film is pressed onto the object from a pressing device at a second work station. At the same time, the adhesive is hardened at the second work station. As a result, the relief structure of the embossing lacquer layer is pressed into the adhesive and is then present as a negative form of this relief structure. At the points where no adhesive was applied to the object in the first step, no relief structure is embossed on the object. The transfer film is then completely, i.e. together with the embossing lacquer layer arranged completely on the carrier film, pulled off the object on which only the relief structure molded in the adhesive remains. Additional UV radiation can preferably be carried out after the transfer film has been removed in order to achieve particularly good curing of the adhesive. The relief structure is optically effective due to the optical boundary layer air / adhesive with the corresponding difference in the refractive index of both media (e.g. adhesive approx.1.5; air approx.1.0). The optical effectiveness can be increased if the substrate has a high absorption capacity in the visible wavelength range, that is to say is preferably colored dark, in particular black.

In this alternative embodiment, the transfer film can preferably be used several times, i.e. are pressed and pulled off again in several independent process steps, the material of the embossing lacquer layer on the transfer film or alternatively the material of the transfer film itself is selected in such a way that after the transfer film has been detached from the adhesive, no or only the slightest part of the adhesive is present stick to the embossing lacquer layer or the transfer film and contaminate or partially fill the relief structure. That the adhesion between the relief structure and the adhesive should preferably be as low as possible.

The holding device can be, for example, a holding mandrel onto which the object is pushed. The object is then held exclusively from the inside by friction of the holding mandrel with the inner surface of the object. Alternatively, the holding device can be the object also hold from the outside if the entire surface of the object is not to be printed or coated.

In a preferred embodiment of the method, the transfer film is pressed onto the object by rotating the object about the axis of rotation, by guiding the transfer film tangentially to the outer circumference of the object, and by pressing the transfer film along the line of contact between the object and the transfer film pushes the object. By rotating the object through 360 ° around the axis of rotation, the decorative material can thus be applied to the object at all points. In a further preferred embodiment of the method, the pressing device is moved such that the surface surface speed of the pressing device corresponds to the surface speed of the object. In addition, the transfer film is moved such that the surface speed of the transfer film corresponds to the surface speed of the object. This ensures that the pressure device, transfer film and object do not rub against each other. This prevents the adhesive from smearing on the object. The risk of damage to the transfer film or the object also decreases.

In a further preferred embodiment of the method, the pressing device has a cylinder which can be rotated about the cylinder axis. The transfer film can be pressed onto the object in that the transfer film is guided between the cylinder and the object while the cylinder rotates around the cylinder axis and the object around the axis of rotation.

Alternatively, the transfer film can be pressed onto flat objects by moving the cylinder linearly over the stationary object while rotating the cylinder about the cylinder axis.

In a further preferred embodiment of the method, the pressing device has a plate. In this case, the transfer film can be guided directly along the plate and thereby pressed against the object.

According to the invention, the adhesive is a UV adhesive, ie an adhesive that can be polymerized with the introduction of energy by means of ultraviolet radiation (UV = ultraviolet) and thus cures. For example, mercury vapor lamps, for example high-pressure mercury lamps, doped high-pressure mercury lamps, carbon arc lamps, xenon arc lamps, metal halogen lamps, UV lasers or UV light-emitting diodes can be used as UV radiation sources. Alternatively, electron beam curing can also be carried out.

The duration of an irradiation of the adhesive while pressing the transfer film with UV radiation is preferably in the range of less than one second. The duration of irradiation of the adhesive after the backing film has been peeled off from the applied decorative material with UV radiation is preferably in the range from approximately 0.005 s to 0.05 s, preferably approximately 0.015 s for a 5 mm reference length with a UV LED with a radiation power from 5 W / cm ² to 20 W / cm ² , preferably max. 16 W / cm ² and a power setting between 40% and 100%.

In addition to applying the cold adhesive that crosslinks under UV radiation, cold adhesive can of course also or additionally be applied to the at least one primer layer of the transfer film.

It has proven effective if the cold adhesive or UV adhesive which crosslinks under UV radiation is applied to the object in an application amount in the range from 1 g / m ² to 3 g / m ² . Depending on the absorbency of the object used, the amount of cold glue is to be varied, objects which are not very absorbent and / or free of open pores, in particular with amounts of cold glue in the range from 1 g / m ² to 2 g / m ² and more absorbent and / or open-pored Objects in particular with amounts of cold adhesive in the range of 2 g / m ² to 3 g / m ^{2 are} applied. A varnish that adheres sufficiently to the object and later to the decoration material, in particular a clear or colored and thereby transparent, translucent or opaque screen printing varnish or flexographic varnish, can also be used as the adhesive or cold adhesive. If the adhesive is applied as a transparent, translucent or opaque colored layer, several adhesives in different colors and / or grayscale can also be used, for example to form a multicolored motif in the form of a symbol, logo, coat of arms, letters or numbers the motif can be composed of partial areas of the individual colors and / or grayscale, the areas of the area being able to be arranged side by side and / or overlapping. The individual colors and / or grayscale can also be applied in a raster, i.e. it is possible to apply the individual colors and / or grayscale in a grid, for example with three or four colors (e.g. as a CMY or CMYK grid; C = Cyan, M = magenta, Y = yellow / yellow, K = black / black) to produce a true color image. The individual halftone dots of the color layers are next to one another and / or one above the other.

It is particularly preferred if radiation with a wavelength in the range from 250 nm to 420 nm is used as UV radiation for irradiating the adhesive crosslinking under UV radiation, or the radiation used has a maximum intensity in this wavelength range. An LED-UV unit with a wavelength in the range from 380 nm to 420 nm, particularly preferably 380 nm to 400 nm, is preferably used.

• UV-Klebermenge: 1 g
• Walzengeschwindigkeit: 100 m/min
• Messtemperatur: 20 °C
• Messdauer: 2 min.

The UV-crosslinking adhesive used has, in particular, the following viscosities, measured using the MCR 101 measuring device from Physica (measuring cone: CP25-1 / Q1; measuring temperature: 20 ° C):
Viscosity at shear rate 25 1 / s: preferably 120 to 220 Pas, in particular 180 Pas Viscosity at shear rate 100 1 / s: preferably 40 to 90 Pas, in particular 80 Pas
Furthermore, the UV-crosslinking adhesive used preferably has a tack value in the range from 18 to 25, in particular from 22. The "tack" or the so-called initial adhesion is determined using the Inkomat 90T / 600 measuring device from Prüfbau. The following measurement conditions were selected:

• Amount of UV glue: 1 g
• Roll speed: 100 m / min
• Measuring temperature: 20 ° C
• Measuring time: 2 min.

In particular, a tesa-resistant adhesion (tesa test, see above) is achieved between the decoration material of the transfer film and the object, the tesa test already after a few minutes when using a conventionally drying cold adhesive and the tesa test immediately after irradiation with UV when using a UV adhesive Radiation could be assessed as passed. Over 90% of the decorative material remained on the object.

In particular, it has proven useful if the transfer film, if appropriate also only its decoration material, has a transmittance in the range for UV radiation in the wavelength range from 250 nm to 420 nm, preferably in the range 380 nm to 420 nm, particularly preferably 380 nm to 400 nm from 5% to 70%, in particular in the range from 20% to 40%. This enables a particularly rapid and in particular complete curing of a cold adhesive based on an adhesive which crosslinks under UV radiation on the object, as a result of which the adhesion of the decorative material to the object is further improved. This is because only when the amount of radiation is sufficiently high is the adhesive crosslinking under UV radiation fully crosslinked and cured and achieves a high adhesive strength, so that detachment of the decoration material areas transferred to the object is reliably prevented from the object. The determining factor for the UV permeability of a transfer film is the layer of a transfer film which has the lowest UV permeability of all existing layers.

In order to achieve the desired high UV permeability of the transfer film even with a decorative layer in the form of a metallic layer when using the UV adhesive it is particularly preferred if the metallic layer only has a layer thickness in the range from 8 nm to 15 nm, preferably in the range from 10 nm to 12 nm. It is also possible for the metallic layer to have a layer thickness in the range from 12 nm to 15 nm. This ensures good visibility and decorative effect of the metallic layer in combination with a high permeability to UV radiation (optical density (OD) approx. 1.2). In conventional transfer foils, metal layers with a thickness in the range of more than 15 nm are usually used in order to achieve optimum brilliance. Due to the resulting high optical density of approximately 2, such conventional metal layers are, however, not sufficiently UV-transparent for the use of a UV adhesive as a cold adhesive.

It has proven useful if the metallic layer is formed from aluminum, silver, gold, copper, nickel, chromium or an alloy comprising at least two of these metals.

If the decorative layer has additional color layers in addition to or as an alternative to the metallic layer, it is advantageous if the overall decorative layer does not exceed an optical density of approximately 1.2 in order to achieve sufficient UV permeability.

In a further preferred embodiment of the method, the pressing device is transparent to UV radiation at least in partial areas. This enables the pressing device to be arranged between a UV radiation source, which generates the UV radiation, and the holding device.

For example, the UV radiation source can be arranged within a cylinder of the pressing device. For this purpose, the cylinder is designed as a hollow cylinder, at least in places. The material of the cylinder is chosen so that the wavelengths of UV radiation, which are required for the curing of the adhesive, can be transmitted through the cylinder. The cylinder can be completely transparent to the UV radiation; however, transparent windows can also be provided in the cylinder, so that UV radiation only emerges from the cylinder when the UV radiation is needed to harden the adhesive.

The area of the object which is to be exposed to UV radiation can preferably be set so that the curing of the UV adhesive has progressed to such an extent when the transfer film is pressed onto the adhesive that the decorative layer of the transfer film adheres to the object and from the carrier film can be solved. Depending on the adhesive used and the intensity of the UV radiation, it may be necessary to expose the adhesive on the object before the line of contact between the object and the transfer film. The area to be exposed can be set, for example, by (possibly adjustable or changeable) diaphragms between the UV radiation source and the object. One or more panels can also be attached directly to the pressing device. The adjustment can also be made by adjusting the divergence of the UV radiation emitted by the UV radiation source. In a further preferred embodiment of the method, the pressing device also has a flexible pressing layer on the holding device. In this way, irregularities in the three-dimensional object, the transfer film and / or the mechanical structure can be compensated. The flexible pressure layer can be made of silicone, for example.

Furthermore, in order to increase the resistance to external mechanical, chemical or thermal influences of the decoration material of the carrier film applied to the object, it is advantageous to expose the applied decoration material with UV radiation again after the carrier film has been peeled off, in order to remove the one arranged under the decoration material Sufficiently harden glue and thus increase the adhesion of the decoration material to the object. For this purpose, an additional UV radiation source can be provided or the UV radiation source can be adjusted accordingly, for example, by means of (possibly adjustable or changeable) diaphragms. The adjustment can also be made by adjusting the divergence of the UV radiation emitted by the UV radiation source.

Once the adhesive has cured sufficiently and the decoration material adheres sufficiently well to the object, additional coating of the object in the region of the decoration material and / or in regions adjacent thereto or on its entire surface can take place in further workstations. A coating can be carried out, for example, by means of one or more additionally applied transparent, translucent or opaque lacquer layers in order to improve the resistance of the object and / or the decoration material and / or to change the visual impression of the object and / or the decoration material. This additional coating can be carried out by downstream printing units, for example screen printing units or flexographic printing units. A decorative material can be coated with a metallically reflective layer, for example by means of translucent colors in order to achieve a colored metallic effect in particular. The decoration material can be coated, for example, by means of transparent relief lacquers for optically visible and / or tactile 3D effects.

It is particularly preferred if the first work station for applying the adhesive, the second work station for pressing on the transfer film and all further work stations are arranged inline, that is to say the processing is carried out without interruption. It is particularly advantageous if the object remains on the holding device in all work stations and passes through all work stations together with the holding device. As a result, high register accuracy with low storage tolerance between the decoration material and the subsequently applied coating can be achieved, since the object does not leave the holding device during the entire process and is reliably fixed on the holding device.

It is also possible in this way to print coatings on the object, in particular by means of screen printing, flexographic printing or digital printing, before the decoration material is applied to the object. These previous coatings can be implemented as transparent, translucent or opaque layers. The decoration material can then, as mentioned above, be applied in an advantageous manner to the previously applied coatings. In particular, the combination of previous coating, subsequently applied decoration material and subsequent repeated coating enables a multitude of optical effects and designs.

In a further preferred embodiment of the method, the pressure layer is transparent to UV radiation at least in partial areas. The areas in which the pressure layer is transparent can be oriented to the areas in which the holding device is transparent. However, the pressure layer can also be completely transparent, while the holding device is only partially transparent.

In a further preferred embodiment of the method, the first work station is a flexographic printing station. The adhesive can then be applied to the three-dimensional object by means of a printing plate attached to the printing form cylinder. Alternatively, the first work station can also be a screen printing station or a digital printing station (for example inkjet). The invention further relates to a device for cold stamping on a three-dimensional object. A device according to the invention has a holding device for holding the object rotatable about an axis of rotation, a first work station having a printing station for applying a UV adhesive to the object and a second work station having a pressing device for pressing a transfer film onto the object and a hardening device for hardening the UV adhesive, the second work station being set up in such a way that the pressing of the transfer film and the curing of the UV adhesive can take place simultaneously, the curing device having a UV radiation source for generating UV radiation.

In a preferred embodiment of the device, the device has a transfer film guide which is designed to guide the transfer film tangentially to the outer circumference of the object. The pressing device is arranged such that it presses the transfer film onto the object along the line of contact between the object and the transfer film. By rotating the object through 360 ° around the axis of rotation, the decorative material can thus be applied to the object at all points.

In a further preferred embodiment of the device, the pressing device can be moved such that the surface surface speed of the pressing device can be adapted to the surface speed of the object. In addition, the transfer film is so movable that the surface speed of the transfer film can be adapted to the surface speed of the object. This ensures that the pressing device, transfer film and object do not rub against one another, that is to say they have no slippage. This prevents the adhesive from smearing on the object. The risk of damage to the transfer film or the object also decreases.

In a further preferred embodiment of the device, the pressing device has a cylinder which can be rotated about the cylinder axis. The transfer film can be pressed onto the object in that the transfer film is guided between the cylinder and the object while the cylinder rotates around the cylinder axis and the object around the axis of rotation.

Alternatively, the transfer film can be pressed onto flat objects by moving the cylinder linearly over the stationary object while rotating the cylinder about the cylinder axis.

In a further preferred embodiment of the device, the pressing device has a plate. In this case, the transfer film can be guided directly along the plate and thereby pressed against the object.

According to the invention, the adhesive is a UV adhesive. The curing device then has a UV radiation source for curing the adhesive. For example, mercury vapor lamps, UV lasers or UV light-emitting diodes can be used as UV radiation sources.

In a further preferred embodiment of the device, the pressing device is transparent to UV radiation at least in partial areas. This enables the pressing device to be arranged between the UV radiation source which generates the UV radiation and the holding device.

For example, the UV radiation source can be arranged within a cylinder of the pressing device. For this purpose, the cylinder is designed as a hollow cylinder, at least in places. The material of the cylinder is chosen so that the wavelengths of UV radiation, which are required for the curing of the adhesive, can be transmitted through the cylinder. The cylinder can be completely transparent to UV radiation; however, transparent windows can also be provided in the cylinder, so that UV radiation only emerges from the cylinder if UV radiation is required for curing the adhesive due to the process.

The area of the object which is to be exposed to UV radiation can preferably be set so that the curing of the UV adhesive has progressed to such an extent when the transfer film is pressed onto the adhesive that the decorative layer of the transfer film adheres to the object and from the carrier film can be solved. Depending on the adhesive used and the intensity of the UV radiation, it may be necessary to expose the adhesive on the object before the line of contact between the object and the transfer film. The area to be exposed can be set, for example, by (possibly adjustable or changeable) diaphragms between the UV radiation source and the object. One or more panels can also be attached directly to the pressing device. The adjustment can also be made by adjusting the divergence of the UV radiation emitted by the UV radiation source.

In a further preferred embodiment of the device, the pressing device also has a flexible pressing layer on the holding device. In this way, irregularities in the three-dimensional object, the transfer film and / or the mechanical structure can be compensated. The flexible pressure layer can be made of silicone, for example.

In a further preferred embodiment of the device, the pressure layer is transparent to UV radiation at least in partial areas. The areas in which the pressure layer is transparent can be oriented to the areas in which the holding device is transparent. However, the pressure layer can also be completely transparent, while the holding device is only partially transparent.

The pressing device and / or the pressing layer is preferably transparent or translucent for UV radiation in the wavelength range from 250 nm to 420 nm, preferably in the range from 380 nm to 420 nm, particularly preferably 380 nm to 400 nm. The transparency or translucency should in particular be 30% to 100%, preferably 40% to 100%. The transparency or translucency depends on the thickness of the pressure layer. Lower transparency or translucency can be compensated for by higher UV intensity.

The pressing device and / or the pressing layer is preferably made of silicone and has a thickness in the region to be irradiated with UV radiation in the range from 1 mm to 20 mm, preferably from 3 mm to 10 mm. The silicone preferably has a hardness of 30 ° Shore A to 70 ° Shore A, preferably 35 ° Shore A to 50 ° Shore A. The silicone can be a hot vulcanizate or cold vulcanizate, preferably a hot vulcanizate.

The shape of the pressure layer can be flat or three-dimensional (three-dimensional curved or curved contour with a smooth or structured / textured surface). Flat pressure layers are particularly suitable for embossing cylindrical geometries and three-dimensionally shaped pressure layers are particularly suitable for non-round, oval and angular geometries. A structured and / or textured surface of the pressure layer can also be advantageous in order to transfer this structure and / or texture in a superimposed manner when transferring the decoration material onto the surface of the object. The structure and / or texture can be an endless pattern or motif or also a single pattern and / or motif or a combination thereof.

• 5 mm dicke Andrückschicht aus Silikon (49° Shore A) mit 15 µm dicker PET-Folie ergibt 73° Shore A (entspricht 49 % Erhöhung).
• 5 mm dicke Andrückschicht aus Silikon (49° Shore A) mit 50 µm dicker PET-Folie ergibt 85° Shore A (entspricht 70 % Erhöhung).
• 10 mm dicke Andrückschicht aus Silikon (47° Shore A) mit 15 µm dicker PET-Folie ergibt 71° Shore A (entspricht 51 % Erhöhung).
• 10 mm dicke Andrückschicht aus Silikon (47° Shore A) mit 50 µm dicker PET-Folie ergibt 78° Shore A (entspricht 59 % Erhöhung).

It has emerged in particular in test series that the surface of a silicone surface of the pressure layer can be adhesive for the transfer film to be processed. Experience has shown that the surface roughness (average roughness value) of such an adhesive surface is below approximately 0.5 μm, in particular between 0.06 μm and 0.5 μm, preferably between approximately 0.1 μm and 0.5 μm. With such an adhesive surface, it is advantageous if an intermediate film, in particular made of PET, is provided between the pressure layer and the transfer film. The intermediate film reduces the adhesiveness of the pressure layer and considerably facilitates the processing of the transfer film because the transfer film no longer adheres to the surface of the pressure layer in a disruptive manner. The thickness of the intermediate film increases the effective hardness of the compensating effect of the silicone stamp. Below are some exemplary embodiments:

• 5 mm thick pressure layer made of silicone (49 ° Shore A) with 15 µm thick PET film results in 73 ° Shore A (corresponds to a 49% increase).
• 5 mm thick pressure layer made of silicone (49 ° Shore A) with 50 µm thick PET film results in 85 ° Shore A (corresponds to a 70% increase).
• 10 mm thick pressure layer made of silicone (47 ° Shore A) with 15 µm thick PET film results in 71 ° Shore A (corresponds to 51% increase).
• 10 mm thick pressure layer made of silicone (47 ° Shore A) with 50 µm thick PET film results in 78 ° Shore A (corresponds to 59% increase).

With this information, it should be noted that on the part of the definition of the measurement requirements for the Shore A measurement method, the measurement of the sandwich from the pressure layer and film is actually no longer permitted. The Shore A measuring method measures a penetration depth of a test specimen between 0 mm and 2.5 mm and prescribes a minimum thickness of the test specimen of 6 mm. The film in connection with the Shore A measuring process thus simulates greater hardness than is actually present. A conclusion from the measured value on the actual / effective hardness is not possible. It can only be said that the effective hardness of the sandwich is greater than the hardness of the silicone stamp and that the film dominates and defines the overall hardness of the sandwich, regardless of the thickness of the silicone layer.

The pressure layer is preferably provided with a non-adhesive surface, so that the use of an intermediate film can be omitted. In this case the overall arrangement is softer, so that a smaller pressing force is sufficient to press the object against the pressure layer. Experience has shown that the surface roughness (average roughness value) of such a non-adhesive surface is above approximately 0.5 μm, in particular between 0.5 μm and 1 μm, preferably between approximately 0.6 μm and 7 μm, further preferably between approximately 0.8 µm and 3 µm.

The pressure device or the pressure layer ensures that the object rolls off safely and evenly under defined conditions and thereby compensates for shape and movement tolerances. The pressing device or the pressing layer has, for example, only a slight contact pressure with objects made of plastic, since these are otherwise deformed, with objects made of harder or more resistant materials such as glass, porcelain or ceramic, as a result of higher shape tolerances and / or higher mechanical stability of the object also slightly higher contact forces advantageous. The pressing force is approximately 1 N to 1000 N. For example, the pressing force can be approximately 50 N to 200 N for objects made of plastic and approximately 75 N to 300 N for objects made of glass, porcelain or ceramic. To additionally deform plastic parts prevent, for example, the object to be decorated can be filled with compressed air in a correspondingly designed holding device during the embossing process.

In a further preferred embodiment of the device, the first work station is a flexographic printing station. The adhesive can then be applied to the three-dimensional object by means of a printing plate attached to the printing form cylinder. Alternatively, the first work station can also be a screen printing station or a digital printing station (for example inkjet).

• Fig. 1a eine schematische Darstellung einer ersten Arbeitsstation einer bevorzugten Ausführungsform einer erfindungsgemäßen Vorrichtung;
• Fig. 1b eine schematische Darstellung einer ersten Arbeitsstation einer weiteren bevorzugten Ausführungsform einer erfindungsgemäßen Vorrichtung (i) in Seitenansicht und (ii) in perspektivischer Ansicht;
• Fig. 2 eine schematische Darstellung einer zweiten Arbeitsstation einer bevorzugten Ausführungsform einer erfindungsgemäßen Vorrichtung;
• Fig. 3 eine schematische Darstellung der ersten Arbeitsstation nach Fig. 1 und der zweiten Arbeitsstation nach Fig. 2 in perspektivischer Ansicht;
• Fig. 4 eine schematische Darstellung einer ersten beispielhaften Halteeinrichtung;
• Fig. 5 eine schematische Darstellung einer zweiten beispielhaften Halteeinrichtung; und
• Fig. 6 eine schematische Darstellung einer zweiten Arbeitsstation einer weiteren bevorzugten Ausführungsform einer erfindungsgemäßen Vorrichtung.

The invention is explained in detail below with reference to the drawings. It shows:

• Fig. 1a a schematic representation of a first workstation of a preferred embodiment of a device according to the invention;
• Fig. 1b a schematic representation of a first workstation of a further preferred embodiment of a device according to the invention (i) in side view and (ii) in perspective view;
• Fig. 2 a schematic representation of a second workstation of a preferred embodiment of a device according to the invention;
• Fig. 3 a schematic representation of the first workstation after Fig. 1 and the second work station Fig. 2 in perspective view;
• Fig. 4 a schematic representation of a first exemplary holding device;
• Fig. 5 a schematic representation of a second exemplary holding device; and
• Fig. 6 is a schematic representation of a second workstation of a further preferred embodiment of a device according to the invention.

Figure 1a shows a first workstation 1, which is designed as a flexographic printing station. A printing plate 12 is attached to a printing form cylinder 11 and determines the motif in which the adhesive is to be applied to the object 4. The adhesive is transferred from a reservoir (not shown) to the printing plate 12 via an anilox roller 13. The adhesive is applied, for example, to the anilox roller 13 with an immersion roller printing unit or with a chambered doctor blade system.

The object 4 is held from the inside by a holding device 3 designed as a holding mandrel 31. The object 4 can also be rotated about this axis by rotating the holding mandrel 31 about the axis of rotation 32. Simultaneously with the holding mandrel 31, the printing form cylinder 11 is also rotated with the printing plate 12, so that the adhesive applied to the printing plate 12 is transferred to the surface of the object 4.

Figure 1b shows a first work station 1, which is designed as a screen printing station. A screen 15 with a fine-mesh fabric determines the motif in which the adhesive is to be applied to the object 4 by making the mesh openings of the fabric at the points where no adhesive is to be applied, for example impermeable to the adhesive with a stencil. With a squeegee 14, the adhesive is printed through the fabric of the screen 15 onto the object 4.

The object 4 is held from the inside by a holding device 3 designed as a holding mandrel 31. The object 4 can also be rotated about this axis by rotating the holding mandrel 31 about the axis of rotation 32. Simultaneously with the rotation of the holding mandrel 31 there is a relative linear movement between the holding mandrel 31 and the sieve 15, so that the object 4 is rolled off along the sieve 15 as a result. The doctor blade 14 remains stationary relative to the holding mandrel 31. The adhesive is thus applied to the object 4 in accordance with the motif defined by the template.

Figures 2 and 3 show a preferred embodiment of a second work station 2. The holding device 3 with the object 4 held thereon was moved further from the first work station 1 to the second work station 2 after the adhesive was applied to the object 4. The second work station has a foil unwind 22 on which the supply of transfer foil 21 is received. The transfer film 21 is guided to the object 4 via a plurality of guide rollers 23. Among other things, the guide rollers 23 allow the web tension of the transfer film 21 to be set in order to guide the transfer film 21 to the object 4 without creases. Two further guide rollers 23a ensure that the transfer film leads tangentially past the object 4 becomes. The used transfer film 21 is finally guided to a film rewinder 24 via further guide rollers 23 and wound thereon.

In the contact area 29 between object 4 and transfer film 21, the transfer film 21 is pressed against the object 4 by a pressing device. The pressing device has a cylinder 25 which is coated with a silicone layer 26 to compensate for unevenness. The cylinder 25 is designed as a hollow cylinder, so that a UV radiation source 27 can be arranged in its interior. So that the UV radiation emitted by the UV radiation source 27 in the direction of the object 4 can emerge from the cylinder 25, both the cylinder 25 and the coating 26 are made of materials which are transparent to the UV radiation required for curing. The cylinder 25 can in particular be made of soda-lime glass, borosilicate glass, PMMA (polymethyl methacrylate, colloquially Plexiglas) or polycarbonate (PC). The coating 26 is mechanically attached to the cylinder 25, in particular by means of terminal strips. However, gluing is also possible by means of adhesives which are highly transparent in particular for the UV radiation used and which have long-term stability under UV radiation.

In operation of the second work station 2, the holding mandrel 31 with the object 4 located thereon is rotated about the axis of rotation 32, while at the same time the transfer film 21 is guided past the object 4. In addition, the cylinder 25 is simultaneously rotated about the cylinder axis 28, so that the transfer film 21 is pressed against the object 4. The rotational speeds of the cylinder 25 and the holding mandrel 31 and the transport speed of the transfer film 21 are matched to one another in such a way that these three elements are moved without rubbing against one another.

The UV adhesive is cured by the UV radiation simultaneously with the pressing of the transfer film 21 onto the object 4. Due to the rotation of the object 4 and the tangential course of the transfer film 21 to the object 4, the transfer film 21 is pulled off the object 4 immediately after hardening. At the points at which adhesive was applied to the object 4, after the adhesive has hardened, the decorative material (for example the metal layer) of the transfer film 21 adheres to the object 4. At the points where there was no adhesive, the decorative material remains on the Transfer film 21.

Further steps for treating the object 4 can be carried out at further work stations (not shown). For example, the object 4 can be printed with different colors, the surface of the object 4 can be treated, for example to ensure better ink absorption, or the object 4 can be finished be provided with a protective layer. These steps can take place at workstations before or after the workstations responsible for cold stamping. The workstations can be arranged, for example, in a longitudinal cycle system or in a rotary cycle system.

Because the cold stamping method according to the invention can be carried out at work stations of a longitudinal cycle system or a rotary indexing system without the object having to be transferred to another holding device, it is possible to easily integrate the cold stamping method into the production process of the object.

The Figures 4 and 5 show exemplary embodiments of holding devices that can be used in a device according to the invention or with a method according to the invention. In the Figure 4 The holding device shown has a holding mandrel 31 onto which the object is pushed. The diameter of the holding mandrel 31 is selected such that the object is held on the holding mandrel 31 by friction. In order to improve the holding of the object on the holding mandrel 31, air can be sucked out through openings 33 at the free end of the holding mandrel 31, as a result of which the object is pulled towards the holding mandrel 31 due to the negative pressure inside. As a result, the object sits firmly on the holding mandrel 31 and can be processed at the work stations, and if necessary also on the entire surface.

In the Figure 5 The holding device shown holds the object 4 (here a bottle by way of example) in that the object 4 is clamped in a holder 35 at one end and is rotatably mounted in a counter bearing 36 at the opposite end. By rotating the holder 35 about an axis, the object 4 is also rotated about its axis of rotation and can be processed at work stations. Such a holding device can be used, for example, if the object 4 does not have an opening on one side which is large enough for a holding mandrel.

Figure 6 shows a further preferred embodiment of a second work station 2. The guidance of the transfer film 21 corresponds essentially to that in FIGS Figures 2 and 3 embodiment shown and will not be described again here. The pressing device, which presses the transfer film 21 against the article 4 in the contact area 29 between the object 4 and the transfer film 21, demonstrates in the embodiment Figure 6 a flat pressure plate 34, which is coated with a silicone layer 26, for example to compensate for unevenness and to reduce the friction between the pressure device and transfer film 21.

The UV radiation source 27 is arranged above the pressure plate 34, ie on the other side of the pressure plate 34 as the transfer film 21. The pressure plate 34 and the coating 26 are made of materials that are transparent to the UV radiation required for curing, so that the UV radiation emitted by the UV radiation source 27 in the direction of the object 4 can pass through the pressure plate 34 and the coating 26. The pressure plate 34 can in particular be made of soda-lime glass, borosilicate glass, PMMA (polymethyl methacrylate, colloquially Plexiglas) or polycarbonate (PC). The coating 26 is mechanically attached to the pressure plate 34, in particular by means of terminal strips or screws. However, gluing is also possible by means of adhesives which are highly transparent in particular for the UV radiation used and which have long-term stability under UV radiation. In operation of the second work station 2, the holding mandrel 31 with the object 4 located thereon is rotated about the axis of rotation 32, while at the same time the transfer film 21 is guided past the object 4.

The UV adhesive is cured by the UV radiation simultaneously with the pressing of the transfer film 21 onto the object 4. Due to the rotation of the object 4 and the tangential course of the transfer film 21 to the object 4, the transfer film 21 is pulled off the object 4 immediately after hardening. At the points at which adhesive was applied to the object 4, after the adhesive has hardened, the decorative material (for example the metal layer) of the transfer film 21 adheres to the object 4. At the points where there was no adhesive, the decorative material remains on the Transfer film 21.

As in the embodiment according to Figures 2 and 3 Further steps for treating the object 4 can be carried out at further workstations (not shown).

The invention is of course not limited to the holding devices shown. Any holding device can be used for the invention, which allows the three-dimensional object to be held in such a way that all locations of the object to be processed are accessible.

The second work stations shown in the drawings need not necessarily be used together with the first work station shown in the drawings. In particular, it is not necessary for the first work station to be a screen printing or a flexographic printing station. The first work station could also be a digital printing station (e.g. inkjet).

LIST OF REFERENCE NUMBERS

1

first workstation

2

second workstation

3

holder

4

object

11

Plate cylinder

12

printing plate

13

anilox roller

14

doctor

15

scree

21

transfer film

22

film processing

23

guide rollers

23a

guide rollers

24

foil take

25

pressure cylinder

26

pressure layer

27

UV radiation source

28

cylinder axis

29

contact point

31

holding mandrel

32

axis of rotation

33

openings

34

pressure plate

35

bracket

36

thrust bearing

Claims (15)

1. Method for cold stamping on a three-dimensional article (4), wherein the article (4) is either rotatable about a rotation axis (32) or is held fixed in place by a holding device (3),
   wherein, in a first step, an adhesive is applied onto the article (4) at a first workstation (1) and
   wherein, in a second step, a transfer film (21) having a decorative layer and a carrier film is pressed by a pressing device onto the article (4) at a second workstation (2), and the adhesive is simultaneously hardened,
   wherein the adhesive is a UV-adhesive, and wherein the hardening of the adhesive takes place by means of irradiation with UV-radiation.
2. Method according to claim 1, wherein the pressing of the transfer film (21) onto the article (4) takes place by the article (4) being rotated about the rotation axis (32),
   by the transfer film (21) being tangentially guided to the outer periphery of the article (4) and by the pressing device pressing the transfer film (21) onto the article (4) along the line of contact between the article (4) and the transfer film (21).
3. Method according to one of the preceding claims, wherein the pressing device is moved in such a way that the surface area velocity of the pressing device corresponds to the surface area velocity of the article (4), and wherein the transfer film (21) is moved in such a way such that the surface area velocity of the transfer film (21) corresponds to the surface area velocity of the article (4).
4. Method according to one of the preceding claims, wherein the pressing device has a cylinder which can be rotated about the cylinder axis (28) or has a flat plate, and/or the pressing of the transfer film (21) onto the article (4) takes place by the transfer film (21) being guided between the cylinder and the article (4) when the cylinder simultaneously rotates about the cylinder axis (28) and the article (4) rotates about the rotation axis (32), and/or the pressing of the transfer film (21) onto the article (4) takes place by the cylinder being linearly guided over the fixed article (4) when the cylinder simultaneously rotates about the cylinder axis (28).
5. Method according to one of the preceding claims, wherein the UV-radiation is generated by a UV-radiation source, in particular with a wavelength in the range of 250 nm to 420 nm, preferably in the range of 380 nm to 420 nm, or with an intensity maximum in this range, wherein the pressing device is transparent for UV-radiation at least in sections and is arranged at least partially between the UV-radiation source and holding device (3).
6. Method according to one of the preceding claims, wherein the pressing device further has a flexible pressing layer (26), and/or the pressing device and/or the pressing layer (26) is transparent or translucent in the wavelength range of from 250 nm to 420 nm, preferably in the range of from 380 nm to 420 nm, preferably with a transparency or translucence in the range of from 30% to 100%, in particular preferably having a transparency or translucence in the range of from 40% to 100%, and/or the pressing device and/or the pressing layer (26) is formed to be flat or three-dimensional, in particular curved or bent, and/or the pressing device and/or the pressing layer (26) at least in sections has a structured and/or textured surface, and/or the pressing device and/or the pressing layer (26) is made of silicone and has a thickness in the range of from 1mm to 20mm, preferably of from 3mm to 10mm, in the region to be irradiated with UV radiation, and/or the silicone has a hardness in the range of from 30° Shore A to 70° Shore A, preferably from 35° Shore A to 50° Shore A.
7. Method according to one of the preceding claims, wherein the decorative layer has at least one metallic layer, at least one dielectric layer and/or at least one in particular transparent, translucent or opaque coloured layer, and/or the coating takes place by means of one or several additionally applied transparent, translucent or opaque varnish layers, and/or the decorative layer has the metallic, dielectric and/or coloured layer respectively over the entire surface or partially, and/or the decorative layer has a varnish with imprinted macroscopic, in particular effective in a refractive manner, and/or microscopic, in particular optically diffractive, relief structures, and/or the decorative layer is applied on the article (4) in a desired location, in particular with positional accuracy preferably having a register accuracy of ± 1mm, further preferably of ± 0.5mm, in particular preferably of <= ± 0.3mm.
8. Method according to one of the preceding claims, wherein the carrier film is removed after the at least partial hardening of the adhesive, and the article (4) is exposed once again to the UV radiation.
9. Method according to one of the preceding claims, wherein, at one or more further workstations after the second workstation (2) for pressing the transfer film (21) and hardening the adhesive, an additional coating of the article (4) takes place in the region of the decorative material and/or in the regions adjacent to it or on its whole surface, and/or
   at one or more further workstations before the first workstation (1) for applying the adhesive, a coating of the article (4) takes place partially or on its whole surface, in particular by means of screen printing, flexographic printing and/or digital printing.
10. Method according to one of the preceding claims, wherein the first workstation (1) for applying the adhesive, the second workstation (2) for pressing the transfer film (21) and hardening the adhesive as well as, where appropriate, all further existing workstations are arranged inline.
11. Device for cold stamping on a three-dimensional article (4), having a holding device (3) for a rotatable holding of the article (4) about a rotation axis (32), a first workstation (1) having a printing station for applying a UV-adhesive on the article (4) and
    a second workstation (2) having a pressing device for pressing a transfer film (21) onto the article (4) and a hardening device for hardening the UV-adhesive, wherein the second workstation (2) is equipped in such a way that the pressing of the transfer film (21) and the hardening of the UV-adhesive can occur simultaneously, wherein the hardening device has a UV-radiation source for generating UV radiation.
12. Device according to claim 11, having a transfer film guide, which is equipped to tangentially guide the transfer film (21) to the outer periphery of the article (4), wherein the pressing device is arranged in such a way that it presses the transfer film (21) onto the article (4) along the line of contact between the article (4) and the transfer film (21), and/or
    the pressing device can be moved such that the surface area velocity of the pressing device can be adapted to the surface area velocity of the article (4), and wherein the transfer film (21) can be moved such that the surface area velocity of the transfer film (21) can be adapted to the surface area velocity of the article (4), and/or
    the pressing device has a cylinder which can be rotated about the cylindrical axis (28) or a flat plate.
13. Device according to one of claims 11-12, wherein the hardening device has a UV-radiation source for generating UV radiation with a wavelength in the range of from 250nm to 420nm, preferably in the range of from 380nm to 420nm, or with an intensity maximum in this range, and/or
    the pressing device is transparent at least in sections for UV radiation and at least partially arranged between the UV radiation source and holding device (3), and/or the pressing device further has a flexible pressing layer (26), and/or
    the pressing device and/or the pressing layer (26) is transparent or translucent in the wavelength range of from 250nm to 420nm, preferably in the range of from 380nm to 420nm, preferably having a transparency or translucence in the range of from 30% to 100%, in particular preferably having a transparency or translucence in the range of from 40% to 100%, and/or
    the pressing device and/or the pressing layer (26) is formed as flat or three-dimensional, in particular curved or bent, and/or the pressing device and/or the pressing layer (26) has at least in sections a structured and/or textured surface, and/or the pressing device and/or the pressing layer (26) is made of silicone and has a thickness in the range of from 1mm to 20mm, preferably from 3mm to 10mm, in the region to be irradiated with UV radiation.
14. Device according to claim 13, wherein the silicone has a hardness in the range of from 30° Shore A to 70° Shore A, preferably from 35° Shore A to 50° Shore A, and/or
    has one or more further workstations for applying an additional coating of the article (4) in the region of the decorative material and/or in the regions adjacent to it or on its entire surface after the second workstation (2) for pressing the transfer film (21) and hardening the adhesive, and/or
    the one or more further workstations are equipped to apply one or more additional transparent, translucent or opaque varnish layers, and/or
    has one or more further workstations for applying a coating of the article (4) partially or on its entire surface, in particular by means of screen printing, flexographic printing and/or digital printing, prior to the first workstation (1) for applying the adhesive.
15. Device according to one of claims 11 to 14, wherein the first workstation (1) for applying the adhesive, the second workstation (2) for pressing the transfer film (21) on and hardening the adhesive, and all further optionally present workstations are arranged inline.

Images