Digitally printed textured wear protection film with adjustable gloss level

Description

[0001] The present invention relates to a method for producing a digitally printed, structured wear protection film, in particular by negative structuring, with an adjustable degree of gloss.

[0002] Textured surfaces for wear protection are known per se and are used in particular to protect decorative panels.

[0003] For the purposes of the invention, the term "decorative panel" refers to wall, ceiling, door, or floor panels that feature a decorative pattern applied to a carrier plate. Decorative panels are used in a variety of ways, both in the interior design of rooms and for the decorative cladding of buildings, for example, in trade fair construction. One of the most common applications for decorative panels is as floor coverings or for cladding ceilings, walls, or doors. These decorative panels often feature a pattern and surface texture intended to imitate a natural material.

[0004] To protect the applied decorative layer, wear or covering layers are usually applied above the decorative layer. Often, such wear or covering layers incorporate a surface texture that mimics a decorative template, so that the surface of the decorative panel has a tactile structure whose shape and pattern are adapted to the applied decoration, thus achieving the most faithful reproduction of a natural material, including its tactile quality.

[0005] When forming structured wear-protection surfaces with paints, the structure is introduced in a known manner using embossing tools.

[0006] A disadvantage of such processes can be that the formation of small and locally limited structures, such as pores, is particularly difficult. Furthermore, the precise alignment of the embossing tools relative to the decoration can cause problems. Moreover, variations in the structure are difficult to implement and small production series, for example, are relatively uneconomical because embossing tools have to be manufactured and replaced for each series. Another disadvantage can be that considerable forces can be required for this type of structuring, which is why the structuring requires a stable substrate and is therefore usually carried out directly on the decorative panel. This can result in particular in limitations in the process control.

[0007] The document WO 2018 / 130580 A1 discloses a decorated and surface-structured wall or floor panel (100) and a method for its production.

[0008] A decorated and surface-structured wall or floor panel (100) is proposed, comprising a carrier (110) made of a plastic composite material, a primer layer (120) arranged on a surface of the carrier, a decorative layer (130) arranged on the primer layer, a layer (140) of a radiation-curable lacquer arranged on the decorative layer, a structured plastic film (150) arranged on the layer of a radiation-curable lacquer, and a top coat layer (160) arranged on the structured plastic film.

[0009] Document EP 3 632 700 A1 discloses a method for producing a structured wear-protection film. The method comprises the following steps: providing a wear-protection base film, applying a moldable, paint-containing cover layer to at least a portion of the wear-protection base film, at least partially structuring the paint-containing cover layer using a digital printing process to create a pattern on the paint-containing cover layer, and at least partially curing the paint-containing cover layer. Furthermore, a structured wear-protection film, the use of a structured wear-protection film, and a decorative panel with a structured wear-protection film are proposed.In summary, the method described above offers the advantage that a particularly detailed structuring of a wear protection surface can be obtained, that the structure can be aligned particularly easily in various ways relative to a decoration, that an economical production of small series is enabled and that restrictions in the process control are reduced.

[0010] Document WO 2018 / 229170 A1 discloses a method for producing a decorative surface on a workpiece (1), comprising the following steps: - feeding (S10) the workpiece (1), which is coated with a liquid layer (2), to a digital printing station; - applying (S12) an agent which is designed to at least partially absorb electromagnetic radiation, at least to a partial area of ​​the surface of the liquid layer (2), or which, in contact with the surface, gives rise to a reaction product which is such that it is capable of at least partially absorbing electromagnetic radiation; - irradiating (S14) the surface of the liquid layer (2) and the agent with electromagnetic radiation having a wavelength of less than 300 nm, preferably less than 250 nm, particularly preferably less than 200 nm. Furthermore, a device (18) for carrying out this method is disclosed.

[0011] The production of structured surfaces for wear protection may therefore still offer potential for improvement.

[0012] It is therefore the object of the present invention to provide improved means for structured surfaces for wear protection, which at least partially overcome the problems known from the prior art.

[0013] This object is achieved by a method for producing a structured wear protection film according to claim 1. Preferred embodiments of the invention are specified in the subclaims or in the description.

[0014] The invention proposes a method for producing a structured wear protection film, comprising the following process steps: a. Providing a wear protection base film, b. Applying a moldable, paint-containing top layer to at least a partial area of ​​the wear protection base film, c. At least partially structuring the paint-containing top layer using a digital printing process to create a structure for the paint-containing top layer, and d. Curing the paint-containing top layer in such a way that the paint-containing top layer is initially partially cured, wherein UV radiation with a wavelength in a range of ≥ 150 nm to ≤ 250 nm is used for partial curing, and wherein the paint-containing top layer is then finally cured, and wherein the partial curing takes place in an atmosphere with a reduced oxygen content compared to normal ambient air; and wherein e.The varnish-containing top layer is treated with means for changing the electrostatic charge of the top layer before being fed to the printing unit for the purpose of partially structuring the varnish-containing top layer and / or during the printing process for the purpose of partially structuring the varnish-containing top layer in the printing unit by electrostatically discharging the top layer.

[0015] A method described above allows significant advantages over the state-of-the-art solutions.

[0016] Surprisingly, it has been shown that when a digital printing process is used to create a structure in a moldable, lacquer-based top layer on a wear-resistant film, a particularly detailed structuring of the wear-resistant surface can be achieved. Furthermore, it has been demonstrated that the structure can be aligned particularly easily relative to a decoration in various ways. Furthermore, economical production of small series is possible, as no embossing tools are required, and restrictions in process control are reduced, as no particularly stable substrate is required.

[0017] In the context of the invention, the term "structured wear protection film" refers to a film that can be applied to panels or other materials, has haptically perceptible structures and protects against wear.

[0018] The term "wear protection base film" in the context of the invention refers to a film that can be applied to panels or other materials, does not require any special structuring, and can serve as a substrate for applying structures. The term "moldable" in the context of the invention refers to a material that is plastically deformable, i.e., changes its shape under the application of force. The material can be liquid or solid, for example. The moldability of the lacquer-containing top layer can be made possible, for example, by appropriately adjusting the viscosity of the lacquer-containing top layer.

[0019] For the purposes of the invention, the term "digital printing process" refers to a computer-controlled direct printing process.

[0020] The term "hardening" in the context of the invention means that the moldable material loses its formability. For example, a liquid moldable material can be solidified. A plastically deformable solid can, for example, be transformed into an elastically deformable solid through hardening. In this case, at least partial hardening or partial hardening can cause the material to partially lose its formability, i.e., lose its formability in certain places, for example, on the surface. It can also be understood that the formability is only reduced and the material does not become completely unformable. It can also be understood as complete hardening or final hardening.

[0021] A method for producing a wear protection film described above thus serves in particular for the improved production of structured surfaces for wear protection.

[0022] In detail, by providing a wear protection base film, a substrate is created on which structuring can take place. By applying a moldable, paint-containing top layer to at least a partial area of ​​the wear protection base film, a structurable layer is created which is held by the wear protection base film and can therefore be easily shaped and yet can be guided through the process with the wear protection base film. By partially structuring the paint-containing top layer using a digital printing process to create a structuring of the paint-containing top layer, a particularly detailed structuring of the paint-containing top layer can be achieved. Since no embossing tools need to be used in the digital printing process, the wear protection base film can provide sufficient stability for structuring as a substrate.By subsequently curing the now structured, lacquer-based top layer, the applied structure is fixed, so that it remains essentially unchanged even under the application of force. The interaction of the components thus results in the aforementioned advantages.

[0023] With regard to the curing, according to which the lacquer-containing top layer is cured in such a way that the lacquer-containing top layer is first partially cured, whereby UV radiation with a wavelength in a range of ≥ 150 nm to ≤ 250 nm is used for the partial curing, and whereby the lacquer-containing top layer is then finally cured, there are significant advantages.

[0024] Partial curing of the lacquer-containing topcoat, which in particular comprises a UV-curable lacquer, with preferably monochromatic radiation with a wavelength in the range of ≥ 150 nm to ≤ 250 nm, i.e., with very short-wave UV rays, leads to polymerization in the uppermost layer of the lacquer. A thin, cured film forms on the surface because the penetration depth of the radiation is limited. Since polymerization also causes volume shrinkage, which in turn manifests itself in varying degrees of surface wrinkles, the film near the surface exhibits micro-wrinkles, which leads to diffuse reflection of the light and thus to a matte surface.

[0025] For this purpose, the wear protection base film with the applied and structured lacquer-containing top layer is preferably transported through a low-oxygen or oxygen-free chamber. This is achieved, for example, by supplying nitrogen to the area where the lacquer-containing top layer is cured with UV radiation.

[0026] The coating layer can then be final cured using UV radiation, preferably with a longer wavelength than the partial cure. The result is a matte surface with high mechanical and chemical resistance.

[0027] Thus, the process allows for highly adjustable gloss levels, particularly through partial curing in the previously described wavelength range. The partial curing parameters, for example, allow the folding of the surface layer and thus the matting or gloss levels to be highly defined and reproducibly adjusted as desired. This allows for effective and easily definable adaptability of the gloss level of the protective layer.

[0028] Advantages of such matting of the surface include, for example, matting down to extremely low gloss levels without additional matting agents, which can make the process simple and economical, while also enabling high reproducibility.

[0029] Furthermore, after complete curing, a surprisingly increased surface hardness is achieved compared to normal, one-step curing. In addition to the high hardness, the resulting protective layer also offers other advantages, such as increased chemical resistance, good cleanliness during use due to the "anti-fingerprint effect," and very good scratch and abrasion resistance.

[0030] Finally, a pleasant feel can be achieved and, with a homogeneous surface, good cross-linkability.

[0031] Exemplary partial curing parameters include, but are not limited to, monochromatic wavelengths of, for example, 172 nm or 222 nm. Furthermore, a lamp power in the range of 10-25 W / cm and / or a dose rate of 10-30 mW / cm² may be advantageous. Line speeds of up to 100 m / min per lamp are possible.

[0032] Since ozone can form at such wavelengths, it can be advantageous to carry out the pre-curing of the lacquer-containing topcoat in such a way that the surface comes into no or only limited contact with oxygen. Accordingly, a closed chamber with a nitrogen feed can be used at least for partial curing. Thus, according to the invention, the lacquer-containing topcoat is present during partial curing in an atmosphere which has a reduced oxygen content compared to normal ambient air, for example under a protective gas atmosphere, such as a nitrogen atmosphere. The residual oxygen content in the set atmosphere is preferably in a range between ≥ 10 ppm and ≤ 300 ppm, in particular between ≥ 100 ppm and ≤ 200 ppm. With such a reduced oxygen content compared to the ambient air, surprisingly, particularly good partial curing results have been achieved.

[0033] This advantageously allows drying with particularly short wavelengths. This results in comparatively less absorption of UV radiation. Furthermore, it ensures that UV radiation does not trigger reactions in the air, such as the formation of ozone. Furthermore, undesirable surface reactions can be avoided, resulting in a particularly stable surface.

[0034] In a further embodiment of the invention, it can be provided that a fixing step takes place directly after the at least partial structuring of the lacquer-containing top layer using a digital printing process. In this step, the introduced structuring is fixed by irradiation at a wavelength in the range of 350 nm to 410 nm, preferably 390 nm to 400 nm, such as 395 nm, to prevent the resulting structures from spreading. Such fixing can be carried out, for example, using LED spotlights and thus requires particularly low energy.

[0035] Furthermore, it can be provided that after the fixing step and before the described partial curing, the structured, lacquer-containing top layer is first gelled by means of further irradiation at a wavelength in the range of 350 nm to 410 nm. The amount of energy applied to gel the structured top layer is preferably greater, in particular significantly greater, than the amount of energy applied in the preceding fixing step. Gelling can particularly preferably be carried out using a gallium emitter.

[0036] With regard to the final curing, it may be advantageous for this to be carried out by UV radiation of a wavelength in a range from > 150 nm to ≤ 450 nm, preferably from ≥ 300 nm to ≤ 410 nm, wherein the final curing preferably uses a longer wavelength compared to the partial curing.

[0037] This advantageously achieves particularly rapid and uniform curing, which in turn can further positively influence the mechanical properties of the surface. In principle, this can advantageously result in a particularly strong surface hardening. This also allows for particularly high chemical resistance. Furthermore, it can enable good curing even without photoinitiators or with only a small amount of photoinitiator. Furthermore, it can enable curing with only a low heat input.

[0038] In particular, it can be provided that the varnish-containing top layer is irradiated in the second curing step, or during the final curing, with UV radiation from a radiation source with a power of ≥ 5 to ≤ 200 W / cm.

[0039] This advantageously ensures that only a minimal amount of heat is introduced into the lacquered topcoat during curing. This also prevents unwanted deformation, while still allowing the lacquered topcoat to cure sufficiently.

[0040] It can be provided that the curing begins less than 5 s, preferably less than 2 s, in particular less than 0.5 s after the structuring.

[0041] This advantageously ensures that the structuring is not changed by subsequent flow before curing.

[0042] It may also be provided that the moldable lacquer-containing top layer is pre-cured before structuring.

[0043] This advantageously allows the viscosity of the lacquer-containing topcoat to be adjusted. This allows the structuring to be created with exceptional detail. This also means that curing is initiated shortly before structuring, so that during structuring, the formed structures reach a hardness sufficient to prevent subsequent flow before final curing.

[0044] By treating the varnish-containing top layer, in particular with the wear-resistant base film, with means for changing the electrostatic charge before being fed to the printing unit for partially structuring the varnish-containing top layer and / or during the printing process for partially structuring the varnish-containing top layer in the printing unit, by electrostatically discharging at least the varnish-containing top layer, the structuring can be further improved. This is because the presence of unwanted and, in particular, undefined charges on the varnish-containing top layer can lead to the printed material being deflected in an undesired manner and the printed image being distorted. This would cause an unwanted or undefined change in the structure. However, this can be significantly improved by electrostatic discharge, so that the desired structure can be formed with high precision and reproducibility.

[0045] Particularly preferably, a defined amount of charge can be applied to the varnish-containing top layer after the electrostatic discharge. Surprisingly, it has been shown that this embodiment can further prevent the occurrence of blurring or deviations of the generated structure from the desired structure during the production process. An undefined electrostatic charge potentially building up in the substrate to be printed during the production process can lead to an undefined deflection of the printed material on its way from the print head to the surface to be printed.Depending on the production speed and the material selected for the wear protection base film or the lacquer-containing top layer, this effect occurs in varying degrees, so that it is assumed that the wear protection base film or the lacquer-containing top layer, depending on their material, is electrostatically charged during transport within the production plant and that this charge is sufficient to cause the observed effect.

[0046] By applying a defined electrostatic charge to the wear-resistant base film or the varnish-based top layer, the undefined deflection of the printed material caused by an unpredictable electrostatic charge can be prevented. Surprisingly, it has been found that the printed image and thus the resulting structure can be further improved compared to simply discharging electrostatic charges.

[0047] Furthermore, electrostatic charging after electrostatic discharging can enable a particularly defined electrostatic charge, as local charge peaks can be prevented. The type (positive or negative polarity) and magnitude of the introduced or applied charge can be selected depending on the material of the wear protection base film or the lacquer-containing top layer, the printing process, and / or other factors.

[0048] For example, a discharge can be performed in a range of greater than or equal to 7 kV. Alternatively or additionally, the electrostatic charging can be performed in a range from greater than 0 kV to less than or equal to 15 kV. Surprisingly, it has been shown that, in particular, discharging by a predetermined amount of charge and / or charging by a predetermined amount of charge can lead to a particularly detailed structure.

[0049] It can further be provided that a device for dissipating electrostatic charges and / or a device for supplying electrostatic charges is designed as a strip having a surface that runs essentially parallel to a surface of the wear-protection base film or the lacquer-containing top layer and is arranged in the direction of the wear-protection base film. Essentially parallel can mean, in particular, a deviation or tolerance of ≤ 20%, in particular < 10%, for example < 1% of the distance between the surface of the strip and the surface of the lacquer-containing top layer. In principle, the strip can be aligned transversely to the direction of movement or production direction of the film and positioned above and / or below the discharged arrangement.

[0050] Alternatively or additionally, the device for discharging electrostatic charges and / or applying electrostatic charges may comprise at least one roller, brush, or lip made of a conductive material, which electrically contacts the carrier at least in the region of the printing unit and is connected to an electrical ground potential. The electrical ground potential can be provided, for example, by grounding. The strip, roller, brush, or lip is preferably formed, at least in the contact area with the lacquer-containing cover layer, from a material with a conductivity of ≥ 1*10 3< Sm -1<.

[0051] Furthermore, it can be provided that the device has an ionization device upstream of the printing unit, by means of which an ionized air jet is directed over the varnish layer. It has been shown that exposure to ionized air is suitable for further reducing or increasing the occurrence of electrostatic charging on the substrates.

[0052] It can also be provided that the wear-protection base film and / or the moldable, paint-containing top layer comprise an acrylate-based plastic composition, in particular a polyurethane-modified acrylate plastic composition. It is understood that the moldable, paint-containing top layer comprises the plastic composition in a still uncured form, so that the top layer is moldable, and that the wear-protection base film comprises the plastic composition in an at least partially cured form, so that it can serve as a substrate for the moldable, paint-containing top layer.

[0053] According to a further preferred embodiment of the invention, it can be provided that the wear protection base film has a plastic composition based on a polyolefin, alone or in a mixture with other polymers, in particular other polyolefins. In particular, it can be provided that the film of the wear protection base film consists of a corresponding polyolefin-based plastic. Suitable polyolefins are polyethylene, polypropylene, polymethylpentene, polyisobutylene, polybutylene, or mixtures or copolymers thereof, such as polyethylene-polypropylene copolymers. In particular, it can be provided that the film of the wear protection base film comprises an isotactic polypropylene, preferably consists of such a polypropylene. Furthermore, it can be provided that the film of the wear protection base film comprises a cycloolefin copolymer (COC), in particular consists of such a cycloolefin copolymer.

[0054] This advantageously ensures that the structured wear protection film is flexible overall and at the same time has particularly good protective properties, such as stability, scratch resistance, heat resistance, water resistance and the like.

[0055] The high-energy, short-wave UV radiation not only leads to radical polymerization of the acrylate groups, but also to additional crosslinking of the monomers. This significantly increases surface hardness.

[0056] The plastic composition may preferably comprise a dipropylene glycol diacrylate, preferably in an amount of > 0 to ≤ 15 wt.% based on the plastic composition, and a reaction product of pentaerythritol, epichlorohydrin and acrylic acid, preferably in an amount of ≥ 2 to ≤ 15 wt.% based on the plastic composition.

[0057] More preferably, the plastic composition may additionally comprise a catalyst, preferably in an amount of ≥ 1 to < 10 wt.% based on the plastic composition. The catalyst may preferably be a tertiary ammonium salt, in particular a tertiary ammonium salt selected from the group consisting of tetrabutylammonium bromide, methyltrioctylammonium chloride, benzyltriethylammonium chloride, hexadecyltrimethylammonium bromide, and mixtures thereof. In a particularly preferred embodiment of the invention, the catalyst may be tetrabutylammonium bromide.

[0058] More preferably, the plastic composition may additionally comprise a photoinitiator, preferably in an amount of ≥ 0.1 to ≤ 2 wt.% based on the plastic composition.

[0059] In this regard, the photoinitiator may be a phosphine oxide, preferably an aromatic phosphine oxide, in particular phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

[0060] According to a particularly preferred embodiment, the plastic composition can contain acrylate resin in a concentration between ≥ 25 wt.% and ≤ 50 wt.%, dipropylene glycol diacrylate between ≥ 10 wt.% and ≤ 25 wt.%, trimethylolpropane triacrylate (ethoxylated) between ≥ 1 wt.% and ≤ 10 wt.%, and triethylene glycol diacrylate between ≥ 1 wt.% and ≤ 10 wt.%.

[0061] In addition, the plastic composition may contain conventional components such as fillers, auxiliaries such as defoamers or rheology aids, or inert diluents.

[0062] In particular, it can be provided that the moldable, lacquer-containing top layer and the wear-protection base film both have the same plastic composition. This can ensure that the moldable, lacquer-containing top layer and the wear-protection base film consist essentially of the same material after the lacquer-containing top layer has cured. This improves, for example, the visual appearance of the structured wear-protection film, since the wear-protection base film and the lacquer-containing top layer also have the same optical properties after curing, thus preventing unwanted light refraction between the two layers.

[0063] It can further be provided that the wear protection base film and / or the moldable lacquer-containing cover layer comprises hard materials, preferably in an amount between ≥ 5 wt.% and ≤ 40 wt.%, wherein the hard materials preferably have an average grain diameter between 10 µm and 250 µm.

[0064] For the purposes of the invention, the term "hard materials" refers to materials that exhibit sufficient hardness. For example, the hard materials can have a Mohs hardness of at least ≥ 8, preferably at least ≥ 9. Examples of suitable hard materials are titanium nitride, titanium carbide, silicon nitride, silicon carbide, boron carbide, tungsten carbide, tantalum carbide, aluminum oxide (corundum), zirconium oxide, zirconium nitride, or mixtures thereof.

[0065] This advantageously ensures that the structured wear protection film is particularly abrasion-resistant. Hard materials in the wear protection base film provide abrasion protection across the entire surface of the structured wear protection film. Hard materials in the moldable, lacquer-based top layer provide abrasion protection for the structure after the lacquer-based top layer has cured. This can reduce the dulling of the structure due to stress.

[0066] It can further be provided that the moldable, lacquer-containing top layer has a thickness of ≥ 1 µm to ≤ 5 mm, preferably of ≥ 10 µm to ≤ 200 µm, in particular of ≥ 50 µm to ≤ 60 µm. It can be provided that the lacquer-containing top layer is applied in an application quantity of ≥ 50 g / m 2< to ≤ 100 g / m 2< , preferably ≥ 60 g / m 2< to ≤ 80 g / m 2< , for example 70 g / m 2< .

[0067] This advantageously ensures that a sufficiently deep structure can be created, resulting in a particularly good haptic impression. Furthermore, it advantageously ensures that curing can occur sufficiently quickly, so that the structure is not altered by any flow of the moldable top layer.

[0068] Furthermore, it can be provided that the moldable lacquer-containing cover layer comprises a material curable by electromagnetic radiation, in particular a material curable by UV radiation and / or IR radiation, particularly preferably a material curable by UV radiation.

[0069] This advantageously ensures that curing can occur particularly quickly and in a targeted manner. For the purposes of the invention, a material curable by electromagnetic radiation is understood to be a material in which a chemical reaction can be initiated by electromagnetic radiation, thereby making the material harder. For example, this chemical reaction can be a polymerization or a crosslinking reaction.

[0070] In one embodiment of the invention, it can be provided that the partial structuring of the lacquer-containing cover layer is carried out with a digital printing process by spraying a displacement ink with an inkjet process.

[0071] According to the invention, the term "spraying" refers to the application of a material as an aerosol jet onto a substrate in the form of particles and / or droplets. According to the invention, the term "displacement ink" refers to an ink, for example a liquid, solution, or suspension, that partially displaces a moldable material upon impact. According to the invention, the term "inkjet process" refers to a process in which an ink is applied in a matrix via one or more nozzles.

[0072] This advantageously results in the moldable, lacquer-containing top layer being structured by the impact of the displacement ink. At the points where the ink impinges, the impact of a drop or particle can create depressions such as craters or valleys, at the bottom of which the ink remains. The displacement during the formation of the depression can also create a ridge around the depression, representing a raised area. Thus, a negative structuring process can be applied using a displacement ink.

[0073] In one embodiment of the invention, the displacement ink can be provided essentially with an ink composition selected from the group consisting of acrylate-based plastic, polyurethane-modified acrylate plastic, water, organic solvent, or mixtures thereof. This advantageously ensures that the displacement ink can be sprayed well and has good displacement properties.

[0074] In a preferred embodiment of the invention, it can be provided that the ink composition comprises an ethoxyethyl acrylate, preferably 2-(2-ethoxyethoxy)ethylene acrylate, preferably in an amount of ≥ 20 to ≤ 40 wt.%, based on the ink composition. In addition, it can be provided that the ink composition comprises an ethoxylated polyol esterified with acrylic acid, preferably 1,1,1-trimethylolpropane ethoxylate triacrylate, preferably in an amount of ≥ 20 to ≤ 40 wt.%, based on the ink composition. In addition, it can be provided that the ink composition comprises a urethane acrylate, preferably in an amount of ≥ 10 to ≤ 20 wt.%, based on the ink composition. In addition, it can be provided that the ink composition comprises pentaerythritol acrylic acid ester, preferably in an amount of ≥ 5 to ≤ 10 wt.%, based on the ink composition.Furthermore, it can be provided that the ink composition comprises amine-modified acrylic oligomers, in particular reaction products of tripropylene glycol diacrylate with diethylamine, preferably in an amount of ≥ 5 to ≤ 10 wt.%, based on the ink composition.

[0075] It can further be provided that the displacement ink is cured during the curing of the lacquer-containing top layer and cross-linked with the lacquer-containing top layer. This advantageously achieves the creation of a particularly stable structure, since the displacement ink bonds with the lacquer-containing top layer.

[0076] Furthermore, it can be provided that the displacement ink is evaporated during the curing of the lacquer-containing top layer. This advantageously enables particularly deep structures, since the applied displacement ink is removed from the recesses.

[0077] Preferably, it can be provided that at least one of a droplet velocity, a droplet volume, and a position of the sprayed displacement ink is varied according to a three-dimensional digital template. By varying and controlling the droplet velocity, it can advantageously be achieved that structures with different depths can be created. Furthermore, it is achieved that structures with different wall sharpness can be created. In particular, it can therefore be varied whether the structure has sharp or blunt edges. By varying the droplet volume, the depth of the structure can also be varied. Furthermore, the width of depressions can be varied, in particular. By varying the position, the location of depressions and elevations can be adjusted.This provides complete control over the structuring process, allowing a desired structure to be created based on a three-dimensional digital template. The term "three-dimensional digital template" is understood to mean a template that reproduces a structure in three dimensions, whereby the template can be stored, for example, in the form of a CAD model on a digital medium.

[0078] Furthermore, it can be provided that the digital template is generated based on a decorative pattern, with the digital template providing complementary recesses and elevations corresponding to the haptic properties of the decorative pattern. This advantageously ensures that the haptic perception of the wear protection film matches the visual perception of a decorative pattern, so that, for example, a decorative panel creates a particularly high-quality overall impression.

[0079] It can also be advantageous for the method to additionally comprise the following steps: f. Providing a carrier having a decoration on at least a partial area of ​​the carrier, and g. Applying the wear protection base film to the decoration, wherein the application of the wear protection base film to the decoration is carried out before the application, structuring and at least partial curing of the lacquer-containing top layer, wherein the structuring of the lacquer-containing top layer is preferably produced at least partially synchronously with the decoration.

[0080] This advantageously allows the structuring to be applied directly in synchronization with a decorative pattern. For example, using alignment marks, the structuring can be directly aligned using the digital printing process so that the structuring is created synchronously with the decorative pattern.

[0081] A "carrier" can be understood, in particular, as a layer serving as the core or base layer in a finished panel, which can, in particular, comprise a natural material, such as a wood-based material, a fiber material, or a material comprising a plastic. For example, the carrier can provide a panel with suitable stability or contribute to it. The carrier can, in particular, be a web-like carrier or a plate-like carrier.

[0082] Particularly preferably, the carrier can comprise a material comprising a plastic. Plastics that can be used in the production of corresponding panels or the carriers include, for example, thermoplastics, such as polyvinyl chloride, polyolefins (e.g., polyethylene (PE), polypropylene (PP), polyamides (PA), polyurethanes (PU), polystyrene (PS), acrylonitrile butadiene styrene (ABS), polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polyetheretherketone (PEEK), or mixtures or copolymers thereof. The plastics can contain conventional fillers, for example, calcium carbonate (chalk), aluminum oxide, silica gel, quartz powder, wood flour, and gypsum. They can also be colored in a known manner. The carrier can preferably comprise talc as a filler material.

[0083] A decoration can be applied to the carrier, for example, by a printing process. Furthermore, a suitable printing substrate can be provided on the carrier. Alternatively, within the meaning of the present invention, it is not excluded that the decoration is applied in such a way that, for example, a pre-printed fiber layer, such as a paper layer, or even a pre-printed film, such as made of polyethylene, polypropylene, or polyvinyl chloride, is applied to the carrier, or that the fiber layer or film is printed on the carrier.

[0084] The decor can also be provided with a lacquer-containing layer, which is located between the wear protection base film and the decor after the wear protection base film has been applied.

[0085] For further advantages or features of the method, reference is made to the description of the wear protection film, the use, the decorative panel and the figure.

[0086] A structured wear protection film is also proposed.

[0087] In detail, a structured wear protection film is provided, preferably produced according to the method according to the invention, comprising a wear protection base film with a lacquer-containing cover layer applied and fixed to at least a partial area of ​​the wear protection base film, wherein the lacquer-containing cover layer has structures produced by the digital printing process.

[0088] Such a wear-protection film can be used to protect a material from wear. The film can be pre-applied to the material to be protected or can be present separately. This advantageously allows the film to be flexibly applied to the material to be protected, unlike, for example, a directly applied wear-protection layer. This advantageously allows such a film to be produced independently of the material to be protected.

[0089] Furthermore, such a wear protection film can be produced easily and very adaptably with an adjustable gloss level or an adjustable matting.

[0090] For further advantages or features of the wear protection film, reference is made to the description of the method, the use, the decorative panel and the figure.

[0091] The use of a structured wear protection film according to the invention is further proposed. In detail, the use of a structured wear protection film for protecting a decorative panel is provided, wherein the decorative panel has a carrier and a decoration on at least a partial area of ​​the carrier and the structured wear protection film is applied to the decoration, wherein during the application of the structured wear protection film, the structuring of the lacquer-containing top layer is aligned at least partially synchronously with the decoration. This means that the structured wear protection film is only applied to a decorative panel after production. The at least partially synchronous alignment of the structuring of the wear protection film with the decoration can be achieved, for example, using alignment marks.

[0092] This advantageously allows for greater flexibility in the production of protected decorative panels. The subsequent application of the structured wear-resistant film according to the invention also prevents the panel from deforming due to possible shrinkage during the curing of wear-resistant layers directly on the panel.

[0093] For further advantages or features of use, reference is made to the description of the wear protection film, the method, the decorative panel and the figure.

[0094] A decorative panel with a structured wear-resistant film is also proposed.

[0095] In detail, a decorative panel with a structured wear-protection film is provided. The decorative panel comprises a carrier with a decoration applied to at least a partial area and a structured wear-protection film according to the invention applied to the decoration. The structuring of the structured wear-protection film is synchronous with the decoration, at least in partial areas. Furthermore, a suitable printing substrate can be provided between the carrier and the decoration. The decoration can also be provided with a lacquer-containing layer located between the wear-protection film and the decoration.

[0096] This ensures that the decorative panel is well protected against wear and tear and at the same time has a particularly detailed structure whose haptic perception corresponds to the visual perception of a decor, creating a particularly high-quality overall impression.

[0097] Furthermore, such a decorative panel can be easily and very adaptably manufactured with an adjustable degree of gloss or an adjustable matting.

[0098] For further advantages or features of the decorative panel, reference is made to the description of the wear protection film, the method, the use and the figure.

[0099] The invention is further explained below with reference to a figure.

[0100] Fig. 1 shows the process sequence of a method according to the invention for producing a structured wear protection film 10 during the production of a decorative panel (32). First, a wear protection base film 12 is provided. This is in the embodiment according to Figure 1arranged on a carrier 14 and more precisely on a decorative layer or a decoration 16 of the carrier 14. The carrier is arranged on a transport device 100 which moves the carrier 14 in the direction of the arrow.

[0101] Furthermore, an application unit 18 is shown, which applies a moldable, paint-containing cover layer 20 to at least a partial area of ​​the wear-protection base film 12. It can be provided that the wear-protection base film 12 and / or the moldable, paint-containing cover layer 20 comprises an acrylate-based plastic composition, in particular a polyurethane-modified acrylate plastic composition. Alternatively or additionally, it can be provided that the wear-protection base film 12 and / or the moldable, paint-containing cover layer 20 comprises hard materials, preferably in an amount between 5% by weight and 40% by weight, wherein the hard materials preferably have an average grain diameter between 10 µm and 250 µm.According to a further embodiment, the wear protection base film 12 can comprise at least one polymer selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polyisobutylene, polybutylene and cycloolefin copolymers, or copolymers or mixtures of the aforementioned.

[0102] Furthermore, a device 22 for discharging electrostatic charges from the cover layer 20 is provided, which can contact the cover layer 20 or operate without contact. A device 24 for supplying electrostatic charges to the cover layer 20 is provided behind the device 22 for discharging electrostatic charges from the cover layer 20. This device 24 can also contact the cover layer 20 or operate without contact. It may be preferred that a discharge be carried out in a range of greater than or equal to 7 kV and / or that the electrostatic charging be carried out in a range of greater than 0 kV to less than or equal to 15 kV.

[0103] Downstream of the device 24 for applying electrostatic charges to the cover layer 20, the carrier 14 is guided into a printing unit 25, in which the lacquer-containing cover layer 20 is structured using a digital printing process to create a structuring 26 of the lacquer-containing cover layer 20. In detail, it is provided that the at least partial structuring of the lacquer-containing cover layer 20 using a digital printing process is carried out by spraying a displacement ink using an inkjet process, in particular wherein at least one of a drop velocity, a drop volume, and a position of the sprayed displacement ink is varied according to a three-dimensional digital template. The digital template can be generated based on the decoration, wherein the digital template provides complementary depressions and elevations corresponding to the haptics of the decoration.

[0104] Particularly preferably, the displacement ink consists essentially of an ink composition selected from the group consisting of acrylate-based plastic, polyurethane-modified acrylate plastic, water, organic solvent or mixtures thereof.

[0105] After the structuring 26 has been introduced into the cover layer 20, the lacquer-containing structured cover layer 20 can be cured. This is done, in particular, by first partially curing the lacquer-containing cover layer 20 by a first radiation source 28, wherein UV radiation with a wavelength in a range of ≥ 150 nm to ≤ 250 nm is used for partial curing, and wherein the partially cured lacquer-containing cover layer 20 is subsequently finally cured by a second radiation source 30.

[0106] With regard to curing, it can be provided that monochromatic UV radiation with a wavelength in a range of 172 or 222 nm is used for partial curing and / or that radiation with a wavelength in a range of > 150 nm to ≤ 450 nm, preferably from ≥ 300 nm to ≤ 410 nm, is used for final curing.

[0107] At least the partial hardening is realized in such a way that the cover layer 20 in the area of ​​treatment with UV radiation is present in an atmosphere with an oxygen content reduced compared to ambient conditions, for example in a protective gas atmosphere.

[0108] After the cover layer 20 has cured, the wear protection film 10, in particular comprising the wear base film 12 and the structured, cured cover layer 20, can be completed. It should be noted that the method with a wear protection base film 12 on a carrier 14 is only exemplary, and the carrier 14 is not mandatory, so that the wear protection base film 12 can also be arranged directly on the transport device 100.

[0109] According to a further embodiment of the invention, it can be provided that directly after the at least partial structuring of the lacquer-containing top layer with a digital printing process by means of printing unit 25, a fixing step takes place, in which the introduced structuring is fixed by irradiation at a wavelength in the range of 350 nm to 410 nm, such as 395 nm. Such fixing can preferably be carried out using LED lamps and thus particularly with low energy.

[0110] Subsequently, it can be provided that, after the fixing step and before partial curing by means of the radiation source 28, the structured, lacquer-containing top layer is first gelled by means of further irradiation at a wavelength in the range of 350 nm to 410 nm. The amount of energy applied to gel the structured top layer is preferably greater, in particular significantly greater, than the amount of energy applied in the preceding fixing step and can be achieved, for example, by using a gallium radiator. List of reference symbols

[0111] 10Wear protection film 12Wear protection base film 14Carrier 16Decor 18Application unit 20Cover layer 22Device for discharging electrostatic charges 24Device for supplying electrostatic charges 25Printing unit 26Structuring 28First radiation source 30Second radiation source 32Decorative panel 100Transport device

Claims

1. Method of producing a structured antiwear film (10), comprising the method steps: a. providing a base antiwear film (12); b. applying a formable lacquer-containing top layer (20) onto at least a partial area of the base antiwear film (12); c. at least partial structuring of the lacquer-containing top layer (20) by use of a digital printing process in order to produce a structuring (26) of the lacquer-containing top layer (20); and d. curing the lacquer-containing top layer (20) in such a way that the lacquer-containing top layer (20) is first partially cured, wherein UV radiation having a wavelength in a range from ≥ 150 nm to ≤ 250 nm is used for the partial curing, and wherein the lacquer-containing top layer (20) is subsequently finally cured, and and whereby the partial curing takes place in an atmosphere with reduced oxygen content compared to normal ambient air wherein e. the lacquer-containing top layer (20) is treated before being fed to the printing unit (25) for partial structuring of the lacquer-containing top layer (20) and / or during the printing process for partial structuring of the lacquer-containing top layer (20) in the printing unit (25) by means for changing the electrostatic charge of the top layer (20) by electrostatically discharging the top layer (20).

2. Method according to claim 1, wherein the base antiwear film (12) and / or the formable lacquer-containing top layer (20) comprises an acrylate-based plastic composition, in particular a polyurethane-modified acrylate plastic composition.

3. Method according to claim 1 or 2, wherein the base antiwear film (12) and / or the moldable lacquer-containing top layer (20) comprises hard materials, preferably in an amount between ≥ 5 wt.-% and ≤ 40 wt.-%, wherein the hard materials preferably have an average grain diameter between ≥ 10 µm and ≤ 250 µm.

4. Method according to any one of the preceding claims, wherein the formable lacquer-containing top layer (20) comprises a material curable by electromagnetic radiation, in particular a material curable by UV radiation and / or IR radiation.

5. Method according to any one of the preceding claims, wherein the at least partial structuring of the lacquer-containing top layer (20) is carried out by use of a digital printing process by spraying on a displacement ink by use of an ink-jet process, in particular wherein at least one of a droplet speed, a droplet volume and a position of the sprayed on displacement ink are varied according to a three-dimensional digital template.

6. Method according to claim 5, wherein the digital template is generated based on a decoration, wherein the digital template provides complementary depressions and elevations corresponding to the haptics of the decoration.

7. Method according to claim 5 or 6, wherein the displacement ink consists essentially of an ink composition selected from the group consisting of acrylate-based plastic, polyurethane-modified acrylate plastic, water, organic solvent, or mixtures thereof.

8. Method according to any one of the preceding claims, wherein radiation having a wavelength in a range from > 150 nm to ≤ 450 nm, preferably from ≥ 300 nm to ≤ 410 nm, is used in the final curing.

9. Method according to any one of the preceding claims, wherein monochromatic UV radiation having a wavelength in a range of 172 or 222 nm is used for partial curing.

10. Method according to any one of the preceding claims, wherein a defined amount of charge is supplied to the lacquer-containing top layer (20) subsequently to the electrostatic discharge.

11. Method according to any one of the preceding claims, wherein an electrostatic discharge is carried out in a range of greater than or equal to 7 kV and / or wherein the electrostatic charging is carried out in a range of greater than 0 kV to less than or equal to 15 kV.

12. Method according to any one of the preceding claims, further comprising the method steps: f. providing a carrier (14) comprising a decoration (16) on at least a partial area of the carrier (14); and g. applying the base antiwear film (12) onto the decoration (16), wherein the application of the base antiwear film (12) onto the decoration (16) is carried out prior to the application, structuring and at least partial curing of the lacquer-containing top layer (20), wherein the structuring of the lacquer-containing top layer (20) is preferably produced at least partially synchronously with the decoration (16).

13. Method according to any one of the preceding claims wherein the atmosphere during the partial curing is set to a remaining oxygen content in a range of between > 10 ppm and > 300 ppm.

14. Method according to claim 13, wherein the partial curing occurs under an inert gas atmosphere.