TRANSFER FILM, ITS USE AND METHOD FOR PRODUCEING A TRANSFER FILM AND METHOD FOR PRODUCEING AN INJECTION MOLDED ARTICLE DECORATED WITH A TRANSFER LAYER OF A TRANSFER FILM

Description

[0001] The invention relates to a transfer film, its use, and a method for producing a transfer film. Furthermore, the invention relates to a method, in particular an IMD method (IMD = In-Mold Decoration), for producing an injection-molded article decorated with a transfer layer of a transfer film.

[0002] Composite molded parts made from a film and a plastic molded body have been known for some time. Composite molded parts with a surface with tactile or haptic properties, especially with a soft-touch coating, are becoming increasingly important. Depending on the coating, this can have a velvety, rubbery, or even soft surface. Such molded parts are becoming increasingly important in communications devices as well as in vehicle, ship, and aircraft construction.

[0003] Typically, composite elements made from a soft-touch layer and the plastic component are manufactured by subsequently coating the component. This involves applying a coating containing pigments, fillers, etc., directly to the entire surface in a wet state. The small particles of the pigments, fillers, etc., then create a visual change on the dry surface and, through altered friction, contribute to the tactile soft-touch effect when swiped or touched. An example of a visual change would be a matting finish combined with increased friction when swiped or touched.

[0004] This subsequent, and particularly full-surface, application of the soft-touch layer entails several disadvantages. Firstly, it requires a large number of work steps, some of which must be carried out manually. Furthermore, the scrap rate is comparatively high. Furthermore, this process requires a very thick layer, which is associated with high costs and high material consumption. In addition, the particles protruding from the surface make the surface sensitive to scratches. Another important limitation of this known procedure is that the full-surface application does not allow the creation of decorations or motifs, i.e., a partial soft-touch layer.

[0005] JP 2015-182302 A describes a decorative film and a decorative plastic molded part.

[0006] It is therefore an object of the present invention to provide a transfer film with a soft-touch effect, which can be used in a wide range of applications, in particular in the field of IMD, without the properties in terms of haptics deteriorating.

[0007] The object is achieved with a transfer foil, in particular hot stamping foil, according to claim 1.

[0008] The object is further achieved by a method for producing a transfer film, in particular for use as an IMD soft-touch film, according to claim 9.

[0009] The object is further achieved by a method, in particular an IMD method, for producing an injection-molded article decorated with a transfer layer of a transfer film, comprising the following steps: Arranging a transfer film according to the invention in an injection mold, back-injecting the transfer film with a plastic injection molding compound, peeling off the carrier film together with the master structure from the transfer layer of the transfer film.

[0010] The invention makes it possible to obtain a transfer film or a transfer layer of a transfer film with a soft-touch effect, whereby the decoration of the film can be freely selected, i.e., one is not limited to one color as with full-surface spray painting. Furthermore, areas with different optical properties, particularly with regard to reflection, absorption, and refractive index, such as matte-gloss effects, are possible, and the individual effects can be adapted to the respective application. Furthermore, the film is well suited for use in the IMD process.

[0011] In this case, this is achieved in particular by structuring the surface of the topcoat using the master structure. This allows the functional properties of the topcoat to be controlled, which in particular allows for the tactile feel of the surface, in particular the grip, fingerprint sensitivity, dirt-repellent and / or liquid-repellent functions, and / or the degree of matting to be controlled. The structure incorporated into the topcoat ensures, in particular, the soft-touch effect of the transfer film, in particular the soft-touch effect of the transfer layer of the transfer film.

[0012] According to the invention, a soft-touch effect is understood in particular to mean an effect that creates a pleasant, velvety feel – similar to peach skin. The varnishes used for the topcoat have a particularly soft feel on their surface. Overall, varnishes with a soft-touch effect have a particularly tactile effect on their surface.

[0013] The invention further enables the topcoat to have a structure without requiring it to contain pigments, in particular particles and / or solid particles. This is achieved in particular by the master structure merely being molded into the topcoat. This means, in particular, that the master structure is negatively molded and leaves corresponding depressions in the topcoat. Overall, the film according to the invention can improve the tactile properties, in particular by increasing friction, as well as the optical properties. Furthermore, susceptibility to fingerprints is also reduced.

[0014] The topcoat is formulated to have a soft-touch effect. Ideally, the topcoat is formulated as a soft-touch varnish.

[0015] A textured coating has the master structure. For this purpose, the textured coating preferably has a raised structure or surface.

[0016] In one embodiment, the carrier film consists of a textured coating, in particular a self-supporting textured coating. If the textured coating is self-supporting, it is preferably made of silicone. The textured coating advantageously has a Shore A hardness of 10 to 50.

[0017] The thickness of the self-supporting structural coating is preferably between 10 µm and 5000 µm, in particular between 10 µm and 500 µm, particularly preferably between 10 µm and 250 µm. The master structure is advantageously introduced into the structural coating by embossing. The self-supporting structural coating can, for example, be a directly structured, self-supporting film into which a structure is or is introduced into the film material, preferably by embossing / replication and / or etching and / or engraving and / or laser structuring.

[0018] In a further embodiment, the carrier film comprises a carrier layer and a textured lacquer arranged on the carrier layer in the direction of the transfer layer. The carrier layer is preferably made of ABS, ABS / PC, PET, PC, PMMA, PE, and / or PPP. The layer thickness of the carrier layer is advantageously between 5 µm and 500 µm, in particular between 6 µm and 100 µm.

[0019] Preferably, the textured coating is applied over the entire surface of the carrier layer. This means that the textured coating extends over the entire carrier layer. However, it is also possible for the textured coating to be applied only partially, i.e. in certain areas, on the carrier layer. Preferably, the textured coating in the decor is applied to the

[0020] The structured coating is arranged on the carrier layer. By applying the textured coating only in certain areas of the carrier layer, an overall matte-glossy effect can be achieved. The various matte and / or glossy areas are characterized not only by their different optical properties, particularly with regard to reflection, absorption, and / or refractive index, but also by different friction and tactile properties.

[0021] An optical difference between a matt and a less matt, particularly glossy or even a more glossy area, especially from a visually perceptible gloss difference of 2, measured at a 60° measuring angle with the micro-gloss measuring device from Byk-Gardener, can be perceived with the unaided human eye.

[0022] If the textured coating is applied to the decor or to specific areas of the carrier layer, the resulting areas are typically matte, particularly those areas containing the textured coating, and areas that remain glossy. These glossy areas may be the surface of the carrier layer. However, it is also possible that in areas where no textured coating is present, another layer of coating, particularly a smooth coating, is applied to the carrier layer.

[0023] Preferably, the master structure or the textured coating and / or the topcoat has a homogeneous surface structure at least in some areas. For the purposes of the invention, a homogeneous surface structure is understood in particular to mean a structure designed such that the surface appears uniform, preferably in a single area. No optical surface defects are then visible in that area.

[0024] The structural coating is preferably made of melamine, polyurethane (PU), polyacrylate, polyol, isocyanate, and / or polyvinyl chloride. The structural coating advantageously has a layer thickness of 0.1 µm to 10 µm, in particular 0.5 µm to 7 µm.

[0025] Advantageously, the master structure or textured coating has a texture depth of 1 µm to 10 µm, preferably between 2 µm and 4 µm, in particular between 3 µm and 4 µm. Such a texture depth allows for a particularly good soft-touch effect of the topcoat.

[0026] However, it is also possible for the structural depths to be greater. This is preferably achieved by the master structure or the structural paint having larger particles. By selecting particles of an appropriate size, the structural depth of the master structure or the structural paint can be optimally adapted to the respective application. According to the invention, the master structure or the structural paint has fillers as structural particles. Possible fillers can be silicone beads, mineral fillers (e.g. corundum or ground river pebbles), inorganic fillers (e.g. SiO 2 ) and / or polyurethane particles. 50% to 80% of the structural particles are between 2 µm and 4 µm in size. The remaining 20% ​​to 50% of the particles are made up of larger particles. The size of the larger particles is 6 µm to 15 µm.

[0027] In principle, the particles are not restricted to any fixed shape. The particles can be either angular fragments or spherical. Ideally, the particles in the master structure or the textured coating can have different shapes. It is advantageous if the shape of the particles can be adapted to the specific requirements.

[0028] It is advantageous if the master structure or the structural coating has a chemically inert surface. For the purposes of the invention, an inert surface is understood in particular to mean that the surface does not react, or only reacts to a negligible extent, with potential reaction partners, such as air, water, or the topcoat, under the respective conditions. This ensures that no bond or combination occurs between the topcoat and the master structure, thus enabling separation of the topcoat and master structure.

[0029] The structural coating preferably comprises at least one UV-curable and / or at least one isocyanate component and / or at least one melamine component.

[0030] The topcoat is advantageously made of long-chain polymers. The polymers can be cross-linked. Cross-linking is preferably based on UV curing and / or chemical reactions.

[0031] The topcoat is made of copolymers of PU and polyol and / or copolymers of polyurethane (PU) and polyacrylates.

[0032] The layer thickness of the topcoat is advantageously between 0.5 µm and 100 µm, in particular between 0.2 µm and 50 µm, particularly preferably between 5 µm and 30 µm.

[0033] The topcoat, in particular the binder matrix of the topcoat, can contain fillers, preferably spherical fillers made of PMMA, silicones, polyurethanes, various copolymers, and / or minerals. Furthermore, the topcoat, in particular the binder matrix of the topcoat, can contain silicone-containing acrylates, silicone-containing polyurethanes, oils, waxes, and / or wax dispersions. The use of such additives or fillers can enhance the elasticity of the topcoat and / or the associated tactile or haptic properties, the so-called "feel."

[0034] The topcoat advantageously contains silicones. The use of silicones can improve the scratch resistance, grip, and surface quality of the topcoat. Furthermore, the use of silicones can control the release properties between the topcoat and the textured finish.

[0035] The topcoat preferably contains UV-curable components. The UV-curable components can advantageously be used as secondary or primary binders.

[0036] The topcoat has a gloss level between 20 and 60, preferably between 30 and 50. These comparatively high gloss levels are measured at a measuring angle of 85° using the "micro-gloss" measuring device from BYK-Gardener.

[0037] To further mat the topcoat, the topcoat can contain matting agents. Possible matting agents include silicone beads, mineral fillers (e.g., corundum or ground river pebbles), inorganic fillers (e.g., SiO 2 ), polytetrafluoroethylene (PTFE, Teflon ® ), or polyurethane particles.

[0038] Ideally, the topcoat should have an elongation of at least 50%, preferably at least 100%, particularly preferably at least 200%. This results in a formable topcoat. This type of elongation of the topcoat makes the transfer film particularly suitable for use in IMD processes. During forming in the IMD process, the carrier film absorbs the majority of the tensile forces. The elongation properties of the topcoat ensure, in particular, that the topcoat is not damaged when it comes into contact with the contour of the injection mold, particularly through tearing or microcracks. The elongation values ​​were determined in standardized tensile tests (DIN 53504, ISO 37) using the Zwick Z005 testing device from Zwick GmbH & Co. KG, Ulm.

[0039] It is advantageous if the topcoat has a temperature resistance of up to 200 °C. This ensures that the topcoat can withstand the thermal stresses caused by the injection-molded material, especially in the IMD process, and, in particular, that there is no change in the structure or surface of the topcoat.

[0040] The topcoat or the surface of the topcoat is preferably designed so that it can withstand solvents such as isopropanol and MEK, weathering such as sunlight, rain and / or dew, food such as coffee, cleaning agents and / or mechanical stresses as well as high thermal loads.

[0041] The topcoat, for example, can have a pencil hardness HB (HB = hard black = medium hard). Pencil hardness is measured specifically according to ASTM 3363 using the SH3000 pencil hardness tester from mtv Messtechnik, Erftstadt, Germany. Pencils of varying hardness are moved across the surface to be tested at a defined angle and load. Specifically for ASTM D 3363, the test begins with the hardest pencil and continues downwards along the hardness scale to determine which next softest pencil does not (or no longer) damage the coating and which next softer pencil does not (or no longer) scratch the coating. The combination of surface structure and the softness of the topcoat further improves the tactile properties of the topcoat. In addition, a highly matting effect is created. Overall, a distinct soft-touch effect can be achieved.

[0042] It is conceivable that the topcoat has a lower hardness than the master structure, than the structural coating and / or than known protective coatings of IMD films.

[0043] It is advantageous to have a release layer between the topcoat and the master structure. This ensures reliable detachment of the transfer layer from the carrier film. Furthermore, excessive adhesion between the topcoat and the master structure or the structural coating can be prevented by adding appropriate additives, such as silicones, aliphatic hydrocarbons, etc., to the master structure or the structural coating. However, it is also possible for the topcoat to contain appropriate additives, such as silicones, aliphatic hydrocarbons, etc.

[0044] In order to be able to process the transfer film well, especially in classic decoration processes such as stroke embossing, unwinding or the IMD process, the release force between the topcoat and the master structure or the structural varnish is preferably between 3 N / m and 40 N / m, particularly preferably between 10 N / m and 30 N / m. This ensures easy and safe removal of the transfer layer. For this purpose, the transfer layer is embossed onto an ABS plate with a width of 35 mm and a length of 150 mm at 180 °C and a speed of 13 m / min. The release force is preferably measured on a Zwick / Roell Z 1.0 tensile testing machine at room temperature (20 °C). For this purpose, the transfer layer is pulled off the ABS plate in particular at an angle of 90 ° and a measuring path of 150 mm, whereby the release force is determined.

[0045] The release layer preferably has a layer thickness of 0.001 µm to 2 µm, in particular of 0.05 µm to 1 µm. The release layer can consist of or comprise a wax. This can be, for example, a carnauba wax, a montanic acid ester, a polyethylene wax, a polyamide wax, or a PTFE wax. Furthermore, surface-active substances such as silicones are also suitable as a release layer. Thin layers of melamine-formaldehyde resin-crosslinked lacquers can also serve as a release layer.

[0046] Advantageously, a mediating layer, in particular an adhesion promoter layer or adhesion promoter, is arranged on the side of the topcoat facing away from the carrier film. The mediating layer ensures, in particular, that very good adhesion is established between the topcoat and the other layers of the transfer layer. Furthermore, the mediating layer serves, in particular, as a barrier layer. It prevents substances penetrating the topcoat from the outside from penetrating the other layers of the transfer layer.

[0047] The intermediary layer preferably comprises crosslinkable acrylates, in particular polyacrylates, polyester resins, alkyd resins and their modifications, amino resins, amido resins, or phenolic resins. Isocyanate can be used as a crosslinking component. In principle, all common crosslinking methods are conceivable. UV crosslinking as well as a dual-cure system, i.e., in particular, crosslinking based on external radiation energy and additionally based on chemical reactions, can be used.

[0048] Ideally, the mediating layer has a layer thickness between 0.1 µm and 10 µm, preferably between 0.5 µm and 5 µm, particularly preferably between 0.3 µm and 4 µm.

[0049] Furthermore, the transfer film, in particular the transfer layer, can have a decorative layer, in particular at least one color layer and / or at least one metallization layer and / or at least one adhesive layer or a primer. The layers can be applied over the entire surface or only partially or in specific areas.

[0050] The decorative layer can comprise one or more partial or full-surface color layers to create a pattern and / or motif. The color layers can, in particular, also be in register with the partial areas of the soft-touch coating, with their different optical properties, particularly with regard to reflection, absorption, and / or refractive index. The layer thickness of the decorative layer is preferably 0.1 µm to 10 µm, in particular 0.5 µm to 5 µm.

[0051] Register or registration accuracy refers to the positioning accuracy of two or more elements and / or layers relative to one another. The registration accuracy should be within a specified tolerance and as small as possible. At the same time, the registration accuracy of several elements and / or layers relative to one another is an important feature for increasing process reliability. Precise positioning can be achieved, in particular, using sensor-based, preferably optically detectable, registration marks. These registration marks can either represent specific, separate elements, regions, or layers, or they can themselves be part of the elements, regions, or layers to be positioned.

[0052] The decorative layer can have a replication layer into which diffractive and / or refractive micro- or macrostructures are molded. This replication layer is preferably provided with a reflective layer, which can consist of a metallization and / or a high refractive index (HRI) layer. The reflective layer can be opaque, semitransparent, or transparent.

[0053] One or more of the following structures can be formed in the replication layer: a diffractive structure, a zero-order diffraction structure, a blazed grating, a macrostructure, in particular a lens structure or microprism structure, a mirror surface, a matte structure, in particular an anisotropic or isotropic matte structure.

[0054] The structures in the replication layer can represent a pattern and / or a motif, which can in particular also be arranged in register with the color layers of the decorative layer and / or in register with the partial areas of the soft-touch lacquer.

[0055] Metallization is preferably achieved by vapor deposition. Cr, Sn, and / or Al are particularly suitable metals. Using a layer of metal results in a soft-touch film with a metallic appearance. The vapor-deposited metallization can be applied over the entire surface and optionally retained over the entire surface, or it can be structured using known demetallization processes such as etching, lift-off, or photolithography, leaving only partial coverage. However, the metallization can also consist of a printed layer of metallic pigments in a binder. These printed metallic pigments can be applied over the entire surface or partially and can exhibit different colors in different areas.The metallization may represent a pattern and / or a motif, which may in particular also be arranged in register with the color layers of the decorative layer and / or with the structures of the replication layer and / or in register with the partial areas of the soft-touch lacquer.

[0056] The adhesive layer or primer ensures in particular that there is good adhesion between the transfer film or between the transfer layer of the transfer film and a plastic injection molding compound or a plastic body.

[0057] The adhesive layer or the primer preferably has a layer thickness of 0.1 µm to 10 µm, in particular of 0.1 µm to 3 µm, and can also have several partial layers.

[0058] Advantageously, a haptic lacquer is arranged at least in regions on the side of the carrier layer that repels the topcoat or on the side of the textured lacquer that repels the topcoat. For the purposes of the invention, a haptic lacquer is understood in particular to mean a lacquer that leads to a spatial, deep structuring or deformation of the film. For this purpose, the haptic lacquer is essentially dimensionally stable. Due to the external force, the haptic lacquer presses into the softer, deformable carrier layer and / or the softer, deformable textured lacquer, whereby the latter forms its negative shape. If a film with such a haptic lacquer is further processed, for example in an IMD process or during hot stamping, the haptic lacquer does not deform or deforms only insignificantly.The use of a transfer film with haptic lacquer for the IMD process or for hot pressing enables the formation of spatial depth structures on the transfer layer of an injection-molded article decorated with such a transfer layer. In addition to the soft-touch effect, this allows a haptic or tactile and visually perceptible relief structure to be created partially or over the entire surface. The haptic lacquer can, in particular, also be arranged in register with the partial areas of the soft-touch lacquer and / or with the color layers of the decorative layer and / or with the structures of the replication layer and / or in register with the partial areas of the metallization.

[0059] The haptic lacquer preferably has a layer thickness between 1 µm and 500 µm, in particular between 5 µm and 100 µm.

[0060] The layer thickness of the haptic lacquer determines the depth of the spatial structuring that can be created. To achieve a haptically perceptible, spatial structuring, a haptic lacquer with a thickness of at least 5 µm, preferably at least 10 µm, is required, which is resistant to deformation or only slightly deformed under the processing conditions for the transfer film. The thickness of the haptic lacquer on a carrier film can be varied, allowing spatial structures of varying depths to be created simultaneously.

[0061] It has proven particularly effective when the haptic coating is made of a thermoset or a thermoplastic with a glass transition temperature Tg above 200°C. However, the use of a haptic coating made of a non-crosslinking coating system filled with a filler, with the filler preferably consisting of inorganic fillers such as titanium dioxide, has also proven successful. Such haptic coatings are dimensionally stable and pressure-resistant up to high temperatures, so that deformation of the structural layer under spraying conditions does not occur, or only to a very small extent.

[0062] Furthermore, it has proven particularly effective if the haptic coating is a radiation-curable coating, for example, UV-curable, electron-beam-curable, epoxy-curable, isocyanate-curable, or acid-curable. Such crosslinking coatings exhibit the required dimensional and compressive stability at high processing temperatures and are easy to process even with high solids content.

[0063] It is particularly preferred if the haptic lacquer has a solids content of at least 40%, preferably 100%. The high solids content increases the achievable layer thickness of the haptic lacquer and improves the transcription capability of the haptic lacquer. Thus, the achievable depth of the spatial structures is increased.

[0064] It has proven advantageous if the haptic varnish is colored differently from the carrier film or carrier layer. This allows for visual inspection of the haptic varnish, for example, with regard to its completeness, as well as easier and more precise, even automatic, positioning of the transfer film in the selected processing method.

[0065] It is advantageous if the master relief structure is created by applying the textured varnish to the carrier layer. The textured varnish is preferably applied to the carrier layer in an additional process step. The textured varnish can be printed, particularly at a resolution of up to 150 µm. The textured varnish can be applied to the entire surface of the carrier layer, as well as partially or as a decorative layer. It is also conceivable, in principle, to apply the textured varnish to the entire surface of the carrier layer in a first step and then remove it in sections by etching in a subsequent step.

[0066] If the textured lacquer is arranged only in regions on the carrier layer, then it is advantageous if, in regions on the carrier layer where no textured lacquer is arranged, at least in regions another lacquer, in particular a lacquer with a non-raised surface, preferably with a smooth and / or glossy surface, is applied.

[0067] Advantageously, a slightly matte textured coating is applied, especially printed, to a glossy substrate. However, it is also possible to apply an even more matte textured coating to an already slightly matte substrate. This results in an optical effect, particularly with a visually perceptible gloss difference of 2, measured at a 60° angle using the micro-gloss measuring device from Byk-Gardener. The gloss effect can advantageously be adapted according to design and / or functionality aspects and / or is freely selectable.

[0068] To improve the adhesion between the carrier layer and the textured coating, the carrier layer can be pretreated. This ensures that the textured coating, along with the carrier layer, can be 100% reliably removed from the transferred transfer layer, especially after an IMD process. This can be achieved, in particular, by pretreating the carrier layer. Suitable methods include corona treatment, UV light irradiation, and flame treatment.

[0069] It is advantageous if the topcoat is cured by UV curing or thermally during the production of the transfer film.

[0070] The additional layers of the transfer layer, in particular the intermediary layer or adhesion promoter, the decorative layer, preferably the color layer, and / or the adhesive layer or primer, are advantageously applied to the topcoat by printing. The metallization is applied, in particular, by vapor deposition.

[0071] If the transfer film according to the invention is used in a process, in particular in an IMD process, for producing an injection-molded article decorated with the transfer layer of the transfer film, it is advantageous if the topcoat is already cured during the production of the transfer film, in particular by UV curing and / or thermally. However, it is also possible for the topcoat to be cured as a post-cure film. For the purposes of the invention, curing of the topcoat as a post-cure film is understood in particular to mean UV curing after processing, in particular after forming, on an injection-molded article.

[0072] The use of the transfer film as a soft-touch film has proven ideal. Furthermore, the use of the transfer film according to the invention as an IMD film has proven excellent. The use of the transfer film according to the invention for producing an injection-molded article decorated with the transfer layer, which exhibits a soft-touch effect in the area of ​​the transfer layer, is also ideal. The transfer film with the finished soft-touch coating or soft-touch surface is introduced into an injection mold and then back-injected.

[0073] Injection-molded articles decorated in this way are preferably used as decorative components for motor vehicles, ships, aircraft or in telecommunications equipment or household appliances.

[0074] The invention is explained below using several exemplary embodiments with the aid of the accompanying drawings. In the drawings: Fig. 1: a schematic sectional view of a transfer film. Fig. 2: a schematic sectional view of another transfer film. Fig. 3: a schematic sectional view of another transfer film. Fig. 4: a schematic sectional view of another transfer film. Fig. 5: a schematic sectional view of another transfer film. Fig. 6: a schematic sectional view of another transfer film. Fig. 7: a schematic sectional view of an injection-molded article decorated with a transfer layer.

[0075] Figure 1shows a schematic sectional view of a transfer foil 10. The transfer foil 10, in particular a hot stamping foil, has a carrier foil 12 and a transfer layer 14 arranged on the carrier foil 12 and detachable from the carrier foil 12. The transfer layer 14 comprises a topcoat 16. A master structure is molded onto the carrier foil 12 on its side facing the transfer layer 14, wherein the topcoat 16 comprises a structuring that has a structure complementary to the master structure. It is advantageous if a textured varnish 18 has the master structure.

[0076] The structure incorporated into the topcoat 16 provides, in particular, the soft-touch effect of the transfer film 10. Depending on the structuring of the surface of the topcoat 16 by means of the master structure, the functional properties of the topcoat 16 can be controlled, whereby, in particular, the tactile or haptic properties of the surface, the fingerprint sensitivity, dirt-repellent and / or liquid-repellent functions and / or the degree of matting can be controlled.

[0077] The Figure 1 The carrier film 12 shown preferably has a carrier layer 20 and the structural lacquer 18 arranged on the carrier layer 20 in the direction of the transfer layer 14. The carrier layer 20 is preferably made of ABS, ABS / PC, PET, PC, PMMA, PE, and / or PPP. The layer thickness of the carrier layer 20 is advantageously between 5 µm and 500 µm, in particular between 6 µm and 100 µm.

[0078] The textured paint 18 is in Figure 1arranged over the entire surface of the carrier layer 20. Advantageously, the structural lacquer 18 is made of melamine, polyurethane (PU), polyacrylate, polyol, isocyanate and / or polyvinyl chloride.

[0079] Ideally, the textured lacquer 18 has a layer thickness of 0.1 µm to 10 µm, in particular of 0.5 µm to 7 µm. It is advantageous if the textured lacquer 18 has a texture depth of between 1 µm and 10 µm, preferably between 2 µm and 4 µm, in particular between 3 µm and 4 µm. A texture depth of this type can achieve a particularly good soft-touch effect for the topcoat 16. However, it is also possible for the texture depths to be greater. This is preferably achieved by the master structure or the textured lacquer 18 having larger particles. By selecting particles of a corresponding size, the texture depth of the master structure or the textured lacquer 18 can be adapted to the respective application in the best possible way. According to the invention, the master structure orThe structural paint contains 18 fillers, with 50% to 80% of the structural particles being between 2 µm and 4 µm in size, and the remaining 20% ​​to 50% of the particles being between 6 µm and 15 µm in size.

[0080] The topcoat 16 is advantageously formed from long-chain polymers. The polymers can be cross-linked. Cross-linking is preferably based on UV curing and / or chemical reactions. The topcoat 16 is formed from copolymers of polyurethane (PU) and polyol and / or copolymers of polyurethane (PU) and polyacrylates.

[0081] The layer thickness of the topcoat 16 is advantageously between 0.5 µm and 100 µm, in particular between 0.2 µm and 50 µm, particularly preferably between 5 µm and 30 µm.

[0082] The topcoat 16, in particular the binder matrix of the topcoat 16, can comprise fillers, preferably spherical fillers made of PMMA, silicones, polyurethanes (PU), various copolymers, and / or minerals. Furthermore, the topcoat 16, in particular the binder matrix of the topcoat 16, can comprise silicone-containing acrylates, silicone-containing polyurethanes, oils, waxes, and / or wax dispersions. The use of such additives or fillers can enhance the elasticity of the topcoat 16 and the associated tactile or haptic properties, the so-called "feel."

[0083] Topcoat 16 advantageously contains silicones. The use of silicones can improve the scratch resistance, grip, and surface quality of Topcoat 16. Furthermore, the use of silicone can control the release properties between Topcoat 16 and Textured Coat 18.

[0084] Ideally, the topcoat 16 has an elongation of at least 50%, preferably at least 100%, particularly preferably at least 200%. This enables a formable topcoat 16. Such elongation behavior of the topcoat 16 makes the transfer film 10 particularly well-suited for use in the IMD process.

[0085] Preferably, a release layer 22 is arranged between the topcoat 16 and the structural coating 18. The release layer 22 ensures reliable detachment of the transfer layer 14 from the carrier film 12 by preventing excessive adhesion between the topcoat 16 and the structural coating 18. Instead of or in addition to a release layer 22, it is advantageous if the structural coating 18 and / or the topcoat 16 contain additives, such as silicones, aliphatic hydrocarbons, etc., which reduce the adhesion between the topcoat 16 and the structural coating 18.

[0086] The release layer 22 preferably has a layer thickness of 0.001 µm to 2 µm, in particular of 0.05 µm to 1 µm. The release layer 22 can consist of a wax or comprise a wax. This can be, for example, a carnauba wax, a montanic acid ester, a polyethylene wax, a polyamide wax, or a PTFE wax. Furthermore, surface-active substances such as silicones are also suitable as the release layer 22. Thin layers of melamine-formaldehyde resin-crosslinked lacquers can also serve as the release layer 22.

[0087] Advantageously, a mediating layer 24, in particular an adhesion promoter, is arranged on the side of the topcoat 16 facing away from the carrier film 12. The mediating layer 24 ensures, in particular, that very good adhesion is established between the topcoat 16 and the other layers of the transfer layer 14. Furthermore, the mediating layer 24 advantageously serves as a barrier layer. In particular, it prevents substances penetrating the topcoat 16 from the outside from penetrating the other layers of the transfer layer 14.

[0088] The mediating layer 24 preferably comprises crosslinkable acrylates, in particular polyacrylates, polyester resins, alkyd resins and their modifications, amino resins, amido resins, or phenolic resins. Isocyanate can be used as a crosslinking component. In principle, all common crosslinking methods are conceivable. UV crosslinking as well as a dual-cure system, i.e., in particular, crosslinking based on external radiation energy and additionally based on chemical reactions, can be used.

[0089] Ideally, the mediating layer 24 has a layer thickness between 0.1 µm and 10 µm, preferably between 0.5 µm and 5 µm, particularly preferably between 0.3 µm and 4 µm.

[0090] Furthermore, the transfer film 10, in particular the transfer layer 14, preferably has a decorative layer 26. The decorative layer 26 is in particular a colored layer. The layer thickness of the decorative layer 26 is preferably 0.1 µm to 10 µm, in particular 0.5 µm to 5 µm. The decorative layer 26 is formed over the entire surface. However, it is also conceivable for the decorative layer 26 to be applied only partially or in certain areas.

[0091] The decorative layer 26 can comprise one or more partial or full-surface color layers for creating a pattern and / or motif, which, in particular, also have different optical properties in register with the partial areas of the soft-touch lacquer, particularly with regard to reflection, absorption, and / or refractive index. The layer thickness of the decorative layer 26 is preferably 0.1 µm to 10 µm, in particular 0.5 µm to 5 µm.

[0092] The decorative layer 26 can have a replication layer into which diffractive and / or refractive micro- or macrostructures are formed. This replication layer is preferably provided with a reflective layer, which can consist of a metallization 28 and / or a high refractive index (HRI) layer. The reflective layer can be opaque, semitransparent, or transparent.

[0093] One or more of the following structures can be formed in the replication layer: a diffractive structure, a zero-order diffraction structure, a blazed grating, a macrostructure, in particular a lens structure or microprism structure, a mirror surface, a matte structure, in particular an anisotropic or isotropic matte structure.

[0094] The structures in the replication layer can represent a pattern and / or a motif, which can in particular also be arranged in register with the color layers of the decorative layer 26 and / or in register with the partial areas of the soft-touch lacquer.

[0095] The metallization 28 is preferably produced by vapor deposition. Cr, Sn, and / or Al are particularly suitable metals. By using a layer of metal, a soft-touch film with a metallic appearance is obtained. The vapor-deposited metallization 28 can be applied over the entire surface and optionally remain over the entire surface, or it can be structured using known demetallization processes such as etching, lift-off, or photolithography, thus remaining only partially present. The metallization 28 can also consist of a printed layer of metallic pigments in a binder. These printed metallic pigments can be applied over the entire surface or partially and can have different colors in different surface areas.The metallization 28 can represent a pattern and / or a motif, which can in particular also be arranged in register with the color layers of the decorative layer 26 and / or with the structures of the replication layer and / or in register with the partial areas of the soft-touch lacquer.

[0096] Furthermore, the transfer film 10, in particular the transfer layer 14, preferably has an adhesive layer 30 or a primer. The adhesive layer 30 or the primer ensures, in particular, that there is good adhesion between the transfer film 10 or between the transfer layer 14 of the transfer film 10 and a plastic injection molding compound 36 or a plastic body. The adhesive layer 30 can be applied over the entire surface or only partially or in certain areas. The adhesive layer 30 or the primer preferably has a layer thickness of 0.1 µm to 10 µm, in particular of 0.1 µm to 3 µm.

[0097] Figure 2shows a schematic sectional view of another transfer film 10. In Figure 2 The textured coating 18' is applied partially, i.e., in regions, on the carrier layer 20. Ideally, the textured coating 18' is applied in the decor on the carrier layer 20. By applying the textured coating 18' only in regions on the carrier layer 20, surface areas with different gloss levels or different matting can be realized. The gloss level of the topcoat is between 20 and 60.

[0098] In addition to the different optical properties, particularly with regard to reflection, absorption and / or refractive index, the different surface areas are characterized in particular by different friction and different tactile properties.

[0099] If the textured lacquer 18' is arranged in the decor or in certain areas on the carrier layer 20, then there are preferably areas 40 that have a matte appearance, namely in particular those areas in which the textured lacquer 18' is located, and there are areas 38 that remain glossy. The glossy areas 38 can be the surface of the carrier layer 20. However, it is also possible that in those areas where no textured lacquer 18' is present, another layer of lacquer is applied to the carrier layer 20, in particular a smooth lacquer.

[0100] Figure 3 shows a schematic sectional view of another transfer film 10. The Figure 3 The carrier film 12' shown consists of the structural coating 18'. This is preferably a self-supporting structural coating 18'. The structural coating 18' is preferably made of silicone. The structural coating 18' advantageously has a Shore A hardness of 10 to 50.

[0101] The thickness of the self-supporting structural coating 18' is preferably between 10 µm and 5000 µm, in particular between 10 µm and 500 µm, particularly preferably between 10 µm and 250 µm. Advantageously, the master structure is introduced into the structural coating 18' by embossing.

[0102] The Figure 3 The transfer position 14 shown essentially corresponds to the one shown in Figure 1 shown transfer position 14.

[0103] Figure 4 shows a schematic sectional view of another transfer film 10. The transfer layer 14 of the transfer film 10 has a metallization 28. The metallization 28 is preferably produced by vapor deposition. Cr, Sn and / or Al are particularly suitable as metals. By using a layer of metal, a soft-touch film with a metallic appearance is obtained. The metallization 28 is in Figure 4formed over the entire surface. However, it is also possible for the metallization 28 to be arranged only in certain areas, particularly in the decoration.

[0104] In order to obtain good adhesion between the metallization 28 and the decorative layer 26, an adhesion promoter 24' is arranged between these layers.

[0105] The Figure 4 The carrier film 12 shown essentially corresponds to the one shown in Figure 1 The carrier film 12 shown has a carrier layer 20 and a structural lacquer 18 arranged over the entire surface thereof. However, the structural lacquer 18 can also be arranged only in the decoration on the carrier layer 20.

[0106] Figures 5 and 6each show a schematic sectional view of another transfer film 10, wherein a haptic lacquer 32 is arranged at least partially on the side of the carrier layer 20 that repels the topcoat 16. Haptic lacquer 32 essentially exhibits dimensional stability. If a film with a haptic lacquer 32 is further processed, for example in an IMD process or during hot stamping, the haptic lacquer 32 does not deform or deforms only slightly. The use of a transfer film 10 with a haptic lacquer 32 for IMD or hot pressing enables the formation of spatial structures in the region of the transfer layer 14 on a plastic article 34 decorated with such a layer.

[0107] The haptic lacquer 32 preferably has a layer thickness between 1 µm and 500 µm, in particular between 5 µm and 100 µm. To achieve a haptically perceptible, spatial structuring, a haptic lacquer 32 with a thickness of at least 5 µm, preferably at least 10 µm, is required, which cannot be deformed or can only be deformed slightly under the processing conditions for the transfer film 10.

[0108] The Figure 5 The transfer position 14 shown essentially corresponds to the one shown in Figure 1 shown transfer position 14. The Figure 6 The transfer position 14 shown essentially corresponds to the one shown in Figure 2 shown transfer position 14.

[0109] Figure 7shows a schematic sectional view of an injection-molded article 34 decorated with a transfer layer 10. The injection-molded article 34 is preferably produced using an IMD process. For this purpose, the transfer film 10 is arranged in an injection mold. The transfer film 10 is then back-injected with a plastic injection molding compound 36. In a further step, the carrier film 12, together with the master structure, is peeled off the transfer layer 14 of the transfer film 10. As a result, the topcoat 16, together with the other layers, remains on the plastic injection molding compound 36 and, together with it, forms the injection-molded article 34. The topcoat 16 represents the outer layer of the injection-molded article 34. As a result, the injection-molded article 34 has a soft-touch effect. List of reference symbols

[0110] 10Transfer film 12Carrier film 14Transfer layer 16Topcoat 18Structural coating 20Carrier layer 22Release layer 24Mediating layer / Adhesion promoter 26Decorative layer 28Metallization 30Adhesive layer / Primer 32Haptic coating 34Injection-molded article 36Plastic injection molding compound 38Glossy area 40Matte area

Claims

1. Transfer film (10), in particular hot stamping film, which comprises a carrier film (12) and a transfer ply (14) arranged on the carrier film (12) and able to be detached from the carrier film (12) with a topcoat (16), wherein a master structure is cast on the carrier film (12) on its side facing towards the transfer ply (14), and wherein the topcoat (16) comprises a structuring which has a structure complementary to the master structure, and wherein a structure lacquer (18) has the master structure, wherein the carrier film (12) consists of the structure lacquer (18) or wherein the carrier film (12) has a carrier layer (20) and the structure lacquer (18) arranged on the carrier layer (20) in the direction of the transfer ply (14), and the topcoat (16) is formed in such a way that it has a soft touch effect, wherein the structure lacquer (18) has structure-giving particles, characterised in that 50% to 80% of the structure-giving particles are between 2 µm and 4 µm large, wherein the remaining 20% to 50% of the particles are formed from larger particles, the size of which is from 6 µm to 15 µm, and the topcoat (16) is formed from copolymers made of polyurethane and polyol and / or from copolymers made of polyurethane and polyacrylates, and wherein the topcoat (16) has a gloss level of between 20 and 60.

2. Transfer film (10) according to claim 1, characterised in that the transfer film (12) consists of a self-feeding structure lacquer (18).

3. Transfer film (10) according to one of the preceding claims, characterised in that the master structure or the structure lacquer (18) and / or the topcoat (16) at least regionally has a homogenous surface structure, and / or the master structure or the structure lacquer (18) has a structure depth of from 1 µm to 10 µm, preferably between 2 µm and 4 µm, in particular between 3 µm and 4 µm, and / or the master structure or the structure lacquer (18) has a chemically inert surface.

4. Transfer film (10) according to one of the preceding claims, characterised in that the topcoat (16), in particular the binder matrix of the topcoat (16), has fillers, preferably spherical fillers made of PMMA, silicones, polyurethanes, various copolymers and / or minerals, and / or the topcoat (10), in particular the binder matrix of the topcoat (10), comprises acrylates containing silicone, polyurethanes containing silicone, oils, waxes and / or wax dispersions, and / or the topcoat (16) has UV-curable components.

5. Transfer film (10) according to one of the preceding claims, characterised in that the topcoat (16) has matting agents.

6. Transfer film (10) according to one of the preceding claims, characterised in that the topcoat (16) is formed as soft-touch lacquer and / or a detachment layer (22) is arranged between the topcoat (16) and the master structure or the structure lacquer (18).

7. Transfer film (10) according to one of the preceding claims, characterised in that a promotion layer (24), in particular an adhesion promotion layer, is arranged on the side of the topcoat (16) facing away from the carrier film (12), in particular wherein the adhesion promotion layer (24) has crosslinkable acrylates, in particular polyacrylates, polyester resins, alkyd resins and modifications thereof, amino resins, amido resins or phenol resins, and / or wherein the adhesion promotion layer (24) has a layer thickness of between 0.1 µm and 10 µm, preferably between 0.5 µm and 5 µm, particularly preferably between 0.3 µm and 4 µm.

8. Transfer film (10) according to one of the preceding claims, characterised in that the transfer film (10), in particular the transfer ply (14), has a decorative layer (26), in particular a coloured layer, a metallisation (28) and / or a glue layer (30) or a priming, and / or a haptic lacquer (32) is arranged at least regionally on the side of the carrier layer (20) pointing away from the topcoat (16) or on the side of the structure lacquer (18) pointing away from the topcoat (16).

9. Method for producing a transfer film (10), in particular a transfer film (10) for use as an IMD Soft Touch film, which comprises a carrier film (12) and a transfer ply (14) arranged on the carrier film (12) and able to be detached from the carrier film (12) with a topcoat (16), wherein a master structure, in particular a master relief structure, is introduced into the carrier film (12) or generated, and wherein the topcoat (16) is applied on the master structure, wherein a structure complementary to the master structure of the carrier film (12) is cast into the topcoat (16), and wherein a structure lacquer (18) has the master structure, wherein the carrier film (12) consists of the structure lacquer (18) or wherein the carrier film (12) has a carrier layer (20) and the structure lacquer (18) arranged on the carrier layer (20) in the direction of the transfer ply (14), and the topcoat (16) is formed in such a way that it has a soft-touch effect, wherein the structure lacquer (18) has structure-giving particles, characterised in that 50% to 80% of the structure-giving particles are between 2 µm and 4 µm large, wherein the remaining 20% to 50% of the particles are formed from larger particles, the size of which is 6 µm to 15 µm, and the topcoat (16) is formed from copolymers made of polyurethane and polyol and / or from copolymers made of polyurethane and polyacrylates, and wherein the topcoat has a gloss level of between 20 and 60.

10. Use of the transfer film (10) according to one of claims 1 to 8 as an IMD film.

11. Use of the transfer film (10) according to one of claims 1 to 8 as a soft-touch film.

12. Method, in particular IMD method, for producing a decorated injection moulded article (34) decorated with a transfer ply (14) of a transfer film (10), having the following steps: - arranging a transfer film (10) according to one of claims 1 to 8 into an injection mould, - back-spraying the transfer film (10) with a plastic sprayed material (36), - removing the carrier film (12) together with the master structure from the transfer ply (14) of the transfer film (10).

13. Method according to claim 12, characterised in that a UV-curing of the topcoat (16) is carried out after processing, in particular reshaping on the injection moulded article.