Water-containing topcoat composition for decorative finish films

Abstract

The present invention relates to a water-containing topcoat composition for a decorative finish film, the water-containing topcoat composition comprising from 50% to 95% by weight of a crosslinkable OH-functional acrylic emulsion, relative to the total weight of the topcoat composition, the water-containing topcoat composition being free of formaldehyde-based compounds. The invention also relates to a method for producing such a water-containing finish paint composition, to a kit for producing a finish paint for a decorative finish film, to a decorative finish film, to a method for producing a decorative finish film, to a decorative finish film obtained or obtainable by such a method, to a method for producing a decorative finish film, to a method for producing a decorative finish film, to a method for producing a decorative finish film, to a method for producing a decorative finish film, to a method for producing a decorative finish film, to a method for producing a decorative finish film Use of a topcoat composition or kit for producing a topcoat for a decorative finish film and use of a decorative finish film for coating wooden substrates (beams), edges and / or furniture parts.

Description

[0001] The present invention relates to an aqueous topcoat composition for decorative coating films, a method for producing such an aqueous topcoat composition, a kit for producing a topcoat for decorative coating films, a decorative coating film, a method for producing a decorative coating film, a decorative coating film obtainable or obtainable by such a method, the use of a topcoat composition or a kit for producing a topcoat for decorative coating films, and the use of a decorative coating film for coating wooden substrates (beams), edges and / or furniture parts.

[0002] Film is one of the solid coating materials used for wood-based materials in furniture production, interior design and other fields. In this context, thin products in the form of sheets or rolls, especially made of metal, plastic or impregnated cellulose / pigment mixtures, are called films. During use, films can have decorative properties as well as functional and protective properties, such as protection against mechanical stress.

[0003] Decorative coating films are specially printed or pigmented paper materials with a coated surface. The properties of decorative coating films are determined by the carrier material, the print and, in particular, the topcoat. The carrier material, the ink layer and the coating components have an influence on the appearance of the decorative coating film as well as the properties and behavior of the film in further processing steps (e.g. when coating furniture).

[0004] Various coating systems are known from the prior art which are used as topcoats in the production of decorative finishing films. Acid-curing lacquers (SH lacquers) are two-component coating materials which contain urea and melamine resins and an acidic hardener as a catalyst. They cure by a polycondensation reaction. A disadvantage of these systems is that urea and melamine resins are formaldehyde-based and release formaldehyde during crosslinking. Formaldehyde may also be released from furniture coated with such lacquers. Formaldehyde is classified as toxic and carcinogenic and therefore poses a health risk.

[0005] Radiation-curing lacquers are cured by radiation, in particular ultraviolet radiation (so-called UV lacquers) or electron beams (so-called EBH lacquers). An example of such a radiation-curing lacquer is a monomeric acrylic compound which is cured with a photoinitiator under UV radiation. A disadvantage of such radiation-curing systems is that special radiation-emitting devices and equipment are required for curing, which is associated with additional costs and time. Such radiation-curing lacquers cannot be used on conventional machines for producing decorative finishing films which crosslink by means of thermal dryers.

[0006] Therefore, the problem to be solved by the present invention is to provide an aqueous topcoat composition for decorative finishing films, which at least partially overcomes one or more disadvantages of the prior art. Based on the above-mentioned prior art, a problem to be solved by the present invention is to provide a topcoat composition that is less harmful to health, toxic and carcinogenic before, during and after crosslinking. At the same time, the topcoat composition should be able to be used on conventional machines for producing decorative finishing films. In addition, the topcoat composition should have good processing properties, and the crosslinked topcoat as a decorative finishing film should have good decorative properties as well as good functional properties and protective properties, such as good mechanical stress resistance properties.

[0007] Another problem to be solved by the present invention is to provide a decorative finishing film which has good decorative properties as well as good functional properties and protective properties, such as good resistance to mechanical stress. Such a decorative finishing film should also not release any compounds harmful to health after coating wooden substrates, edges and / or furniture.

[0008] All or some of these problems are solved according to the invention by the aqueous topcoat composition according to claim 1 , the method according to claim 7 , the kit according to claim 9 , the decorative finish film according to claim 11 , the method according to claim 18 , the decorative finish film according to claim 23 , the use according to claim 24 and the use according to claim 25 .

[0009] Advantageous embodiments of the invention are given in the dependent claims and are explained in detail below.

[0010] The present invention provides an aqueous topcoat composition for decorative finishing films, the aqueous topcoat composition comprising 50 wt % to 95 wt % of a crosslinkable OH-functional acrylic emulsion, based on the total weight of the topcoat composition, wherein the aqueous topcoat composition does not contain formaldehyde-based compounds.

[0011] Surprisingly, it has been shown that the aqueous topcoat composition for decorative finishing films according to the present invention has good processing properties and can be used on conventional machines for producing decorative finishing films. At the same time, the topcoat composition exhibits good decorative properties after crosslinking as well as good functional properties and protective properties, such as good mechanical stress resistance properties. In addition, no radiation is required to crosslink the topcoat composition and the topcoat composition has little or no hazardous properties. The latter can be attributed to the fact that the topcoat composition does not contain formaldehyde-based compounds. Formaldehyde-based compounds are understood to refer in particular to compounds that use formaldehyde in their manufacture. These compounds include in particular melamine resins and urea resins.

[0012] OH-functional means that the acrylic emulsion has hydroxyl groups. These hydroxyl groups can preferably react with isocyanates, in particular polyisocyanates, and thus crosslink the crosslinkable OH-functional acrylic emulsion.

[0013] The aqueous topcoat composition according to the invention comprises 50% to 95% by weight of a crosslinkable OH-functional acrylic emulsion, based on the total weight of the topcoat composition. According to a preferred embodiment, the aqueous topcoat composition comprises 60% to 90% by weight, in particular 70% to 85% by weight, based on the total weight of the topcoat composition, of a crosslinkable OH-functional acrylic emulsion.

[0014] The crosslinkable OH-functional acrylic emulsion preferably has a solids content of 20% to 70% by weight, in particular 30% to 60% by weight or 40% to 50% by weight. Such a solids content of the OH-functional acrylic emulsion ensures particularly good processing properties of the aqueous topcoat composition.

[0015] Furthermore, the crosslinkable OH-functional acrylic emulsion has a strength of 100 s at 23 ° C. as determined in accordance with DIN EN ISO 3219. -1 The OH-functional acrylic emulsion preferably has a viscosity of 5 to 500 mPas, in particular 10 to 100 mPas or 15 to 40 mPas at a shear rate of 1.3 %. Such a viscosity of the OH-functional acrylic emulsion enables good processability of the aqueous topcoat composition.

[0016] Furthermore, the crosslinkable OH-functional acrylic emulsion has a minimum film-forming temperature of 30 to 220° C., in particular 35 to 100° C. or 40 to 70° C. A too high minimum film-forming temperature prevents film formation at the temperatures used in conventional machines for producing decorative finish films.

[0017] Furthermore, the crosslinkable OH-functional acrylic emulsion has a glass transition temperature of 20°C to 150°C, in particular 30°C to 110°C or 40°C to 70°C.

[0018] Furthermore, the crosslinkable OH-functional acrylic emulsion has a hydroxyl number of 10 mg KOH / g to 500 mg KOH / g, in particular 30 mg KOH / g to 300 mg KOH / g or 50 mg KOH / g to 150 mg KOH / g, in each case based on the solids content of the crosslinkable OH-functional acrylic emulsion. Such a hydroxyl number enables the OH-functional acrylic emulsion to crosslink consistently and sufficiently and thus ensures good functional and protective properties, such as good resistance to mechanical stress, by the topcoat.

[0019] Furthermore, the crosslinkable OH-functional acrylic emulsion is preferably an OH-functional copolymer emulsion, in particular an OH-functional acrylic acid-methacrylic acid-styrene copolymer emulsion. It has been shown that such OH-functional acrylic emulsions have particularly good processing properties and the topcoats produced therefrom have particularly good functional and protective properties.

[0020] Finally, the crosslinkable OH-functional acrylic emulsion is preferably crosslinkable with isocyanates, in particular with polyisocyanates, and forms polyurethanes during crosslinking. The resulting crosslinked polyurethane topcoat has good decorative, functional and protective properties, such as good resistance to mechanical stress.

[0021] According to a further preferred embodiment, the aqueous topcoat composition has a flow time of 5 to 50 seconds, in particular 11 to 22 seconds at 23° C., determined using a flow cup with a nozzle diameter of 6 mm in accordance with standard ISO 2431. Such a flow time ensures particularly good processing properties of the aqueous topcoat composition.

[0022] According to another embodiment of the present invention, the aqueous topcoat composition has a pH of 5 to 11, in particular 6 to 10 or 7 to 9 at 25°C. Too high or too low pH poses health risks when processing the aqueous topcoat composition. In addition, if the pH of the topcoat composition is too low, the topcoat cannot be fully and completely cured.

[0023] Furthermore, the aqueous topcoat composition may preferably comprise 0.1% to 20% by weight, in particular 1% to 15% by weight or 2% to 10% by weight, of additives, based on the total weight of the topcoat composition.

[0024] In particular, the additive is a wetting agent, a dispersant, a defoamer, a leveling additive, a rheological additive, a matting agent, a surface additive and / or an additive to improve scratch resistance. Such additives improve the processing properties of the topcoat composition and / or the decorative, functional and / or protective properties of the topcoat produced therefrom.

[0025] Suitable wetting agents, dispersants, defoamers, surface additives and / or additives for improving the scratch resistance are known to the skilled worker.

[0026] Suitable matting agents are, for example, amorphous silicates and / or wax dispersions, for example dispersions based on oxidized HDPE.

[0027] Finally, the aqueous topcoat composition may contain 0.1 to 10 wt. %, in particular 0.5 to 7.5 wt. % or 1 to 5 wt. % of a film-forming aid, based on the total weight of the topcoat composition. Suitable film-forming aids are esters such as 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, ether alcohols such as (di)ethylene glycol monobutyl ether and / or diols such as ethylene glycol or propylene glycol.

[0028] According to a particularly preferred embodiment, the aqueous topcoat composition comprises 70 to 85% by weight of crosslinkable OH-functional acrylic emulsion, 2 to 10% by weight of additives, 1 to 5% by weight of film-forming assistant and water, in each case based on the total weight of the aqueous topcoat composition according to the invention.

[0029] According to a further particularly preferred embodiment, the aqueous topcoat composition according to the invention consists of 70 to 85% by weight of crosslinkable OH-functional acrylic emulsion, 2 to 10% by weight of additives, 1 to 5% by weight of film-forming assistant and water, in each case based on the total weight of the aqueous topcoat composition.

[0030] Based on the total weight of the aqueous topcoat composition according to the invention, the sum of all components of the aqueous topcoat composition is 100 wt %. According to a preferred embodiment of the aqueous topcoat composition according to the invention, water makes up the missing component to 100 wt %.

[0031] The present invention further provides a method for preparing an aqueous topcoat composition according to the present invention, the method comprising

[0032] i. providing a crosslinkable OH-functional acrylic emulsion, water and, if necessary, additives and / or membrane-binding aids,

[0033] ii. mixing the crosslinkable OH-functional acrylic emulsion, the water and optionally the additives and / or membrane-binding aids in a mixing ratio such that the aqueous topcoat composition obtained by mixing contains 50% to 95% by weight of the crosslinkable OH-functional acrylic emulsion, based on the total weight of the aqueous topcoat composition.

[0034] What has been described in connection with the aqueous topcoat composition according to the invention and / or the crosslinkable OH-functional acrylic emulsion and / or the additives and / or the membrane-bonding aids can be equally applied to the aqueous topcoat composition and / or the crosslinkable OH-functional acrylic emulsion and / or the additives and / or the membrane-bonding aids according to the method according to the invention.

[0035] The present invention also relates to a kit for producing a topcoat for decorative finishing films comprising component 1 and component 2, wherein component 1 is an aqueous topcoat composition according to the invention and component 2 is an aqueous hardener component, wherein the aqueous hardener component comprises an isocyanate, in particular a polyisocyanate.

[0036] By mixing component 1 and component 2 of such a kit, subsequently applying the mixture to a carrier material and crosslinking, decorative finishing films having good decorative properties as well as good functional and protective properties (such as good resistance to mechanical stress) can be obtained.

[0037] Preferably, the aqueous hardener component comprises an isocyanate, in particular a polyisocyanate, in an amount of 1% to 25% by weight, in particular 5% to 20% by weight, based on the total weight of component 2. Preferably, the polyisocyanate has an NCO content of 5% to 30% by weight, in particular 10% to 20% by weight. Such a hardener component can cure the aqueous topcoat composition according to the invention and react with it to form a polyurethane topcoat layer, which has good decorative properties as well as good functional properties and protective properties, such as good resistance to mechanical stress. If the amount of isocyanate is too low and / or the NCO content is too low, curing is incomplete.

[0038] The invention furthermore relates to a decorative finish film comprising a carrier material and a topcoat layer, wherein the topcoat layer is a polyurethane layer which can be produced by crosslinking the aqueous topcoat composition according to the invention with the above-described aqueous hardener component.

[0039] Such decorative finishing films have good decorative properties as well as good functional properties and protective properties, such as good resistance to mechanical stress. Such decorative finishing films can also be used to coat wooden substrates, edges and / or furniture parts and do not release any harmful compounds before or after coating.

[0040] The topcoat layer may be applied to the entire surface of the carrier material or partially applied to at least one side of the carrier material. If the topcoat layer is applied to the entire surface of the carrier material, the decorative coating film has consistent and uniform surface properties. If the topcoat layer is partially applied to the carrier material, the decorative coating film has a textured surface, which can be textured differently depending on the desired appearance and properties.

[0041] Various materials can be used as carrier materials for the decorative coating film. Preferably, the carrier material is made of plastic and / or paper, in particular polyethylene terephthalate, polypropylene and / or paper. The carrier material is particularly preferably made of paper.

[0042] According to a preferred embodiment, the topcoat layer has a 2 Up to 15 mg / m 2, especially 4g / m 2 Up to 12g / m 2 or 5g / m 2 Up to 11g / m 2 Such a grammage ensures the positive properties of the above-mentioned topcoat layer. If the grammage is too low, the decorative coating film does not have the desired good functional properties and protective properties, such as good mechanical stress resistance properties. In the case of a higher grammage, a larger amount of topcoat composition is required, making the resource efficiency and cost efficiency of the decorative coating film lower.

[0043] The decorative coating film may comprise an ink layer between the carrier material and the topcoat layer. Such an ink layer can be obtained in particular by printing the carrier material using flexographic printing, digital printing and / or gravure printing, in particular web-fed gravure printing. Such an ink layer provides the desired visual impression to be achieved by the decorative coating film. Preferably, the ink layer comprises a binder, in particular a protein binder, especially casein, and a pigment. Suitable pigments for the ink layer of the decorative coating film are known to those skilled in the art.

[0044] According to a preferred embodiment, the decorative coating film comprises a transparent primer layer between the ink layer and the topcoat layer, wherein the transparent primer layer is transparent to electromagnetic waves with a wavelength of 400 nm to 780 nm. Such a transparent primer layer can improve the adhesion of the topcoat layer to the ink layer while maintaining the visual impression of the decorative coating film achieved by the paint layer. It is particularly preferred that the transparent primer layer comprises a cross-linked polyacrylate.

[0045] According to another preferred embodiment, the decorative coating film comprises a pigmented primer layer between the carrier material and the topcoat layer. Such a pigmented primer layer can achieve a consistent and uniform color impression of the decorative coating film and simultaneously improve the adhesion between the carrier material and the topcoat layer. Preferably, the pigmented primer layer comprises a cross-linked polyacrylate and a pigment, in particular, based on the total weight of the pigmented primer layer, the pigmented primer layer comprises an amount of 1% to 70% by weight, in particular 2% to 60% by weight or 5% to 40% by weight of the pigment.

[0046] In a preferred embodiment, the decorative coating film has the following layer structure from one side to the other: carrier material, ink layer, optionally a transparent primer layer, topcoat layer.

[0047] In another preferred embodiment, the decorative coating film has the following layer structure from one side to the other: carrier material, pigmented basecoat layer, topcoat layer.

[0048] According to a preferred embodiment, the decorative coating film has a thickness of 25 g / m 2 Up to 100g / m 2 , especially 45g / m 2 Up to 82g / m2 Such a grammage ensures that the decorative coating film has sufficient stability and that wooden substrates, edges and / or furniture parts can be coated with the decorative coating film. If the grammage is too low, the decorative coating film is very easy to tear during transportation. If the grammage is too high, a larger amount of material is required, so that the resource efficiency and cost efficiency of the decorative coating film are reduced.

[0049] It is particularly preferred for the decorative coating film to be free of formaldehyde-based compounds. Thus, the decorative coating film does not release any formaldehyde that is harmful to health and does not have any properties that are harmful to health.

[0050] The present invention further provides a method for producing a decorative coating film, the method comprising:

[0051] i. providing a carrier material, an aqueous topcoat composition according to the present invention, and an aqueous hardener component,

[0052] ii. mixing the aqueous topcoat composition with the aqueous hardener component,

[0053] iii. applying the mixture prepared in step ii. to the support material,

[0054] iv. crosslinking the aqueous topcoat composition with the aqueous hardener component.

[0055] Such a method can be used to produce decorative coating films having the above-mentioned frontal properties. In addition, the method can be used on conventional machines for producing decorative coating films.

[0056] The application in step iii. can be carried out using, for example, a doctor blade dispensing system. In particular, the application can be carried out by roller coating.

[0057] What has been described above with respect to the decorative coating film, the carrier material and / or the aqueous hardener component according to the invention can also be applied in the same manner to the decorative coating film, the carrier material and / or the aqueous hardener component of the method according to the invention.

[0058] Preferably, the mixing in step ii. is carried out in a mixing ratio of the aqueous topcoat composition to the aqueous hardener component of 20:1 to 1:1 by weight, in particular 15:1 to 3:1 by weight or 12:1 to 6:1 by weight. With the mixture prepared in this way, the crosslinking in step iv. can take place completely and uniformly.

[0059] Furthermore, the crosslinking in step iv. is preferably carried out at 80°C to 250°C, in particular 100°C to 230°C. At such temperatures, crosslinking can occur quickly. Lower temperatures extend the time required for crosslinking and are therefore less efficient. Higher temperatures lead to increased energy consumption and are therefore less efficient.

[0060] The crosslinking in step iv. is preferably carried out in a thermal dryer, in particular a flotation dryer. Preferably, the crosslinking in step iv. is carried out without electron beam curing and without UV curing, in particular without radiation curing. The method can therefore be used on conventional machines for producing decorative finishing films and in particular does not require special radiation-emitting devices and equipment for crosslinking.

[0061] The method according to the present invention may include the following steps before step iii:

[0062] a. Printing the carrier material with an ink layer, wherein the printing is carried out in particular by flexographic printing, digital printing and / or gravure printing, in particular by web-fed gravure printing.

[0063] The decorative coating films produced in this way can therefore have the desired optical properties, in particular patterns and hues.

[0064] The method according to the present invention may further comprise the following steps:

[0065] b. applying a primer composition to the carrier material, in particular wherein the primer composition comprises a crosslinkable polyacrylate, wherein the primer composition optionally comprises a pigment,

[0066] c. Crosslinking the primer composition.

[0067] A preferred sequence of the method steps of the method according to the invention is: step i., step ii., optionally step a., optionally step b., optionally step c., step iii., step iv.

[0068] The method according to the invention can be carried out using an in-line process. The method steps of printing the carrier material and applying the mixture of the aqueous topcoat composition and the aqueous hardener component are carried out in the same machine. For this purpose, the coating system can be installed at the end of the printing press. Alternatively, the application of the mixture of the aqueous topcoat composition and the aqueous hardener component can be carried out offline in a separate coating unit.

[0069] The invention further provides a decorative finish film obtainable or obtainable by the process according to the invention.

[0070] In addition, an object of the present invention is to use the aqueous topcoat composition or kit according to the present invention to produce a topcoat for decorative finishing films. This use enables efficient production of topcoats for decorative finishing films. The topcoats produced in this way have good functional properties and protective properties, such as good resistance to mechanical stress properties.

[0071] Finally, it is an object of the present invention to use the decorative finishing films according to the invention to coat wooden substrates, edges and / or furniture parts, in particular shelves. Wooden substrates, edges and / or furniture parts coated in this way then have the desired decoration, in particular with regard to color design and feel, and are also well protected, for example, from mechanical stresses such as abrasion and scratching.

[0072] The coating can be carried out in particular in a flat-bed press, a laminating system or a packaging system.

[0073] The principles of the present invention will be explained in more detail below using examples, which do not limit the subject matter of the present invention. Example

[0074] Example 1: Preparation of an aqueous topcoat composition for decorative coating films

[0075] Aqueous topcoat compositions were prepared by mixing at room temperature the components shown in Table 1. Amounts are given as weight percent, based on the total weight of the aqueous topcoat composition.

[0076] Table 1: Aqueous topcoat compositions

[0077] Components Amount [wt%] OH functional acrylic-methacrylic-styrene copolymer emulsion (45% solids by weight) 80 Dispersants 0,1 Defoaming agent 1 Flow Additives 0,2 Matting agent 3 Surface Additives 0,5 Membrane binding aids 1 water 14,2

[0078] Example 2A: Preparation of a decorative coating film having an ink layer and a transparent primer layer

[0079] The topcoat composition prepared in Example 1 was used to prepare a topcoat for a decorative finishing film.

[0080] For this purpose, 90 parts by weight of the aqueous topcoat composition from Example 1 were mixed with 10 parts by weight of an aqueous 10% by weight polyisocyanate emulsion as hardener component.

[0081] The decorative finishing film is produced using an inline process on a conventional printing press with a coating unit mounted at the end. The pre-impregnated decorative paper is printed with a water-based ink using web-to-web gravure printing. The transparent primer composition is applied to the printed paper using a doctor blade roller. The subsequent crosslinking of the primer composition is initiated with a flotation dryer at a maximum temperature of 200° C. The mixture prepared from the aqueous topcoat composition and the hardener component is applied to the decorative paper treated in this way by roller coating and crosslinked in a flotation dryer at a maximum temperature of 220° C. The resulting decorative finishing film is then rolled up.

[0082] Example 2B: Preparation of a decorative coating film having a colored primer layer

[0083] The topcoat composition prepared in Example 1 was used to prepare a topcoat for a decorative finishing film.

[0084] For this purpose, 90 parts by weight of the aqueous topcoat composition from Example 1 were mixed with 10 parts by weight of an aqueous 10% by weight polyisocyanate emulsion as hardener component.

[0085] The decorative finishing film is produced using an inline process on a conventional printing press with a coating unit installed at the end. The pigmented primer composition is applied to the pre-impregnated paper using a doctor blade. The subsequent crosslinking of the primer composition is initiated with a flotation dryer at a maximum temperature of 200° C. The mixture prepared from the aqueous topcoat composition and the hardener component is applied to the decorative paper treated in this way by roller coating and crosslinked in a flotation dryer at a maximum temperature of 220° C. The resulting decorative finishing film is then rolled up.

[0086] Example 3A: Coating a Wood Substrate

[0087] The decorative finishing film prepared in Example 2A is applied to a wooden substrate using a packaging machine. The wooden substrate then has the desired color impression printed on the paper and the desired feel. The surface of the wooden substrate is also protected from mechanical stresses such as abrasion and scratching.

[0088] In addition, the decorative coating film produced in Example 2A is applied to a wooden substrate using a laminator. The wooden substrate then has the desired color impression printed on the paper material and the desired feel. In addition, the surface of the wooden substrate is protected from mechanical stresses such as abrasion and scratching.

[0089] Example 3B: Coating a Wood Substrate

[0090] The decorative finishing film prepared in Example 2B is applied to a wooden substrate using a packaging machine. The wooden substrate then has the desired consistent color and feel. The surface of the wooden substrate is also protected from mechanical stresses such as abrasion and scratching.

[0091] In addition, the decorative finishing film produced in Example 2B is applied to a wooden substrate using a laminating system. The wooden substrate then has the desired consistent color and feel. In addition, the surface of the wooden substrate is protected from mechanical stresses such as abrasion and scratching.

Claims

1. An aqueous topcoat composition for decorative finishing films, the aqueous topcoat composition comprising 50% to 95% by weight of a crosslinkable OH-functional acrylic emulsion, based on the total weight of the topcoat composition, wherein the aqueous topcoat composition does not contain formaldehyde-based compounds.

2. The aqueous topcoat composition according to claim 1, characterized in that The aqueous topcoat composition comprises 60% to 90% by weight, in particular 70% to 85% by weight, of a crosslinkable OH-functional acrylic emulsion, based on the total weight of the topcoat composition.

3. The aqueous topcoat composition according to claim 1 or 2, characterized in that The crosslinkable OH-functional acrylic emulsion has a solids content of 20% to 70% by weight, in particular 30% to 60% by weight or 40% to 50% by weight, and / or At 23℃ and 100s -1 The crosslinkable OH-functional acrylic emulsion has a viscosity of 5 mPas to 500 mPas, in particular 10 mPas to 100 mPas or 15 mPas to 40 mPas, determined according to standard DIN EN ISO 3219 at a shear rate of 1.5 %. and / or the crosslinkable OH-functional acrylic emulsion has a minimum film-forming temperature of 30° C. to 220° C., in particular 35° C. to 100° C. or 40° C. to 70° C., and / or the crosslinkable OH-functional acrylic emulsion has a glass transition temperature of 20° C. to 150° C., in particular 30° C. to 110° C. or 40° C. to 70° C., and / or the crosslinkable OH-functional acrylic emulsion has a hydroxyl number of 10 mg KOH / g to 500 mg KOH / g, in particular 30 mg KOH / g to 300 mg KOH / g or 50 mg KOH / g to 150 mg KOH / g, in each case based on the solids content of the crosslinkable OH-functional acrylic emulsion, and / or the crosslinkable OH-functional acrylic emulsion is an OH-functional copolymer emulsion, in particular an OH-functional acrylic-methacrylic-styrene copolymer emulsion, And / or the crosslinkable OH-functional acrylic emulsion can be crosslinked with isocyanates, in particular with polyisocyanates, and form polyurethanes during the crosslinking.

4. An aqueous topcoat composition according to any one of the preceding claims, characterized in that The flow time of the aqueous topcoat composition at 23° C. is 5 to 50 seconds, in particular 11 to 22 seconds, as determined according to standard ISO 2431 using a flow cup with a nozzle diameter of 6 mm. And / or the aqueous topcoat composition has a pH of 5 to 11, in particular 6 to 10 or 7 to 9 at 25°C.

5. An aqueous topcoat composition according to any one of the preceding claims, characterized in that The aqueous topcoat composition comprises 0.1 to 20% by weight, in particular 1 to 15% by weight or 2 to 10% by weight, of additives, in particular wetting agents, dispersants, defoamers, leveling additives, rheological additives, matting agents, surface additives and / or additives for improving scratch resistance, based on the total weight of the topcoat composition.

6. An aqueous topcoat composition according to any one of the preceding claims, characterized in that The aqueous topcoat composition comprises 0.1% to 10% by weight, in particular 0.5% to 7.5% by weight or 1% to 5% by weight, of a film-forming aid, based on the total weight of the topcoat composition.

7. A method for preparing an aqueous topcoat composition according to any one of claims 1 to 6, comprising i. providing a crosslinkable OH-functional acrylic emulsion, water and, if necessary, additives and / or membrane-binding aids, ii. mixing the crosslinkable OH-functional acrylic emulsion, the water and optionally the additives and / or the membrane-binding aid in a mixing ratio such that the aqueous topcoat composition obtained by mixing contains 50 wt. % to 95 wt. % of the crosslinkable OH-functional acrylic emulsion, based on the total weight of the aqueous topcoat composition.

8. The method according to claim 7, characterized in that The aqueous topcoat composition is as defined in any one of claims 1 to 6 and / or the crosslinkable OH-functional acrylic emulsion is as defined in claim 3 and / or the additive is as defined in claim 5.

9. A kit comprising component 1 and component 2 for preparing a topcoat for a decorative coating film, characterized in that: Component 1 is an aqueous topcoat composition according to any one of claims 1 to 6, and component 2 is an aqueous hardener component, wherein the aqueous hardener component comprises an isocyanate, in particular a polyisocyanate.

10. The set according to claim 9, characterized in that The aqueous hardener component comprises isocyanates, in particular polyisocyanates, in an amount of 1% to 25% by weight, in particular 5% to 20% by weight, based in each case on the total weight of the aqueous hardener component, and / or The polyisocyanates have an NCO content of 5% to 30% by weight, in particular 10% to 20% by weight.

11. A decorative finishing film comprising a carrier material and a topcoat layer, wherein the topcoat layer is a polyurethane layer which can be prepared by crosslinking the aqueous topcoat composition according to any one of claims 1 to 6 with an aqueous hardener component according to any one of claims 9 to 10.

12. The decorative coating film according to claim 11, characterized in that: The topcoat layer is applied to the entire surface or a part of the surface of at least one side of the carrier material, and / or The topcoat layer has a 3 mg / m 2 Up to 15 mg / m 2 , especially 4g / m 2 Up to 12g / m 2 or 5g / m 2 Up to 11g / m 2 Weight.

13. The decorative coating film according to claim 11 or 12, characterized in that: The carrier material is made of plastic or paper, in particular polyethylene terephthalate, polypropylene or paper, in particular paper.

14. The decorative coating film according to any one of claims 11 to 13, characterized in that: The decorative coating film comprises an ink layer between the carrier material and the topcoat layer, In particular, the ink layer comprises a binder, in particular a protein binder, in particular casein, and a pigment.

15. The decorative coating film according to claim 14, characterized in that: The decorative finishing film comprises a transparent primer layer between the ink layer and the topcoat layer, wherein the transparent primer layer is transparent to electromagnetic waves with a wavelength of 400 nm to 780 nm, particularly wherein the transparent primer layer comprises cross-linked polyacrylate.

16. The decorative coating film according to any one of claims 11 to 13, characterized in that: The decorative coating film comprises a colored primer layer between the carrier material and the topcoat layer, In particular, the pigmented basecoat layer comprises a crosslinked polyacrylate and a pigment, in particular wherein the pigment is contained in the pigmented basecoat layer in an amount of 1% to 70% by weight, in particular 2% to 60% by weight or 5% to 40% by weight, based on the total weight of the pigmented basecoat layer.

17. The decorative coating film according to any one of claims 11 to 16, characterized in that: The decorative coating film has a thickness of 25 g / m 2 Up to 100g / m 2 , especially 45g / m 2 Up to 82g / m 2 of grammage, and / or The decorative finishing film does not contain formaldehyde-based compounds.

18. A method for preparing a decorative coating film, the method comprising i. providing a carrier material, an aqueous topcoat composition according to any one of claims 1 to 6, and an aqueous hardener component, ii. mixing the aqueous topcoat composition with the aqueous hardener component, iii. applying the mixture prepared in step ii. to the support material, iv. crosslinking the aqueous topcoat composition with the aqueous hardener component.

19. The method according to claim 18, characterized in that The decorative finishing film is as defined in any one of claims 11 to 17, and / or the carrier material is as defined in claim 13, and / or the aqueous hardener component is as defined in any one of claims 9 to 10.

20. The method according to claim 18 or 19, characterized in that The mixing in step ii. is carried out in a mixing ratio of the aqueous topcoat composition to the aqueous hardener component of 20:1 to 1:1 by weight, in particular 15:1 to 3:1 by weight or 12:1 to 6:1 by weight.

21. The method according to any one of claims 18 to 20, characterized in that The crosslinking in step iv. is carried out at 80°C to 250°C, in particular at 100°C to 230°C, and / or the crosslinking in step iv. is carried out in a thermal dryer, in particular a flotation dryer, And / or the crosslinking in step iv. is carried out without electron beam curing and without UV curing, in particular without radiation curing.

22. The method according to any one of claims 18 to 21, characterized in that The method comprises the following steps before step iii: a. printing the carrier material with an ink layer, in particular wherein the printing is carried out by flexographic printing, digital printing and / or gravure printing, in particular by web-fed gravure printing, and / or The method comprises the following steps: b. applying a primer composition to the carrier material, in particular wherein the primer composition comprises a crosslinkable polyacrylate, wherein the primer composition optionally comprises a pigment, c. crosslinking the primer composition.

23. A decorative finishing film obtainable or obtainable by a method according to any one of claims 18 to 22.

24. Use of the aqueous topcoat composition according to any one of claims 1 to 6 or the kit for preparing a topcoat for decorative finishing films according to any one of claims 9 or 10 in preparing a topcoat for decorative finishing films.

25. Use of the decorative finishing film according to any one of claims 11 to 17 or 23 for coating wooden substrates (beams), edges and / or furniture parts, in particular shelves.