Polyester-polyurethane-poly(meth)acrylic hybrid dispersion

Abstract

The present invention relates to a polyester-polyurethane-poly(meth)acrylic hybrid dispersion, which can be obtained by esterifying at least one carboxyl-containing polyurethane, which has an acid value of more than 200 mgKOH / g to 400 mgKOH / g and at least one or more terminal carboxyl groups, with at least one hydroxyl-containing polyester, which has a hydroxyl value of 50 mgKOH / g to 300 mgKOH / g, to obtain a polyester-polyurethane, followed by a step of polymerizing ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, by radical polymerization in the presence of the polyester-polyurethane in step (a), wherein one or more solvents are present and / or used during steps (a) and / or (b) and / or are added after step (b).Furthermore, the present invention relates to a coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion, a coating layer formed from the composition, and a substrate thus coated. Furthermore, the present invention relates to a method for using a coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion in automotive coatings, and to a method for producing a multi-layer coating, wherein at least one coating layer is formed from a coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion.

Description

[Technical field]

[0001] The present invention relates to polyester-polyurethane-poly(meth)acrylic hybrid dispersions and methods for producing polyester-polyurethane-poly(meth)acrylic hybrid dispersions.Furthermore, the present invention relates to coating compositions comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersions, coating layers formed from the compositions, and substrates thus coated.Furthermore, the present invention relates to the use of coating compositions comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersions in automotive coatings, and to methods for producing multi-layer coatings, in which at least one coating layer is formed from a coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion. [Background technology]

[0002] The painting of automotive bodies is carried out with multi-layer coatings. Multi-layer coating systems include, among other things, a primer surfacer layer, which is usually formed on a precoated substrate, followed by one or more basecoat layers and a top clearcoat layer. The individual layers can be baked separately or applied in a wet-on-wet process, where a coating layer is formed on the previous coating layer without an intermediate curing step. A flash-off or drying step is required between two coating steps, in which the subsequent coating layer is applied after the solvent of the coating composition has evaporated. Thus, it is essential to achieve rapid drying during the flash-off or drying step to prevent mixing of the coating compositions after application of the subsequent coating composition. Rapid drying can be achieved, for example, by a high solids content of the coating composition.

[0003] Nowadays, it is common to use an integrated wet-on-wet-on-wet application for painting car bodies, where at least three coating layers are applied in a wet-on-wet-on-wet process. Two integrated paint processes (IPP) are particularly preferred, integrated paint process 1 (IPP1) preferably comprising the application of a primer surfacer composition on an electrocoated metal substrate followed by a flash-off or drying step to form a primer surfacer layer. Then, one or two base coat compositions are applied on top of the primer surfacer layer to form one or two base coat layers, followed by a flash-off or drying step. Then, a clear coat composition can be applied on top of the base coat layer(s) to form a clear coat layer, followed by a flash-off or drying step. Finally, all layers are cured simultaneously in one curing step.

[0004] In the Integrated Paint Process 2 (IPP2), preferably the electrocoated metal substrate is not coated with a primer surfacer layer, but two basecoat compositions are applied in a wet-on-wet application to form two basecoat layers, followed by a flash-off or drying step, with the first basecoat having the primer surfacer function. Then a clearcoat composition is applied to form a clearcoat layer, followed by a curing step to cure all coating layers simultaneously. By curing all coating layers simultaneously, the energy and material costs of the coating process are reduced.

[0005] There are high demands not only on the individual coating layers but also on multi-layer coatings with regard to environmental issues, compatibility of the individual coating layers, good appearance and weather resistance. Good appearance requires good compatibility of the different coating layers of a multi-layer coating.

[0006] Furthermore, the production of the multi-layer coating system should be possible simply and cheaply.

[0007] EP1199342A1 describes the use of binder combinations containing water-miscible hydroxyurethanes to increase the solids content of the respective binder combination.

[0008] Polyester-polyurethane-poly(meth)acrylic hybrid dispersion is known from US10,233,353B2.However, there is still a need to improve basecoat composition to achieve good compatibility between different coating layers.Good compatibility of different coating compositions forming coating layers of multi-layer coating leads to good appearance of multi-layer coating. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] EP1199342A1 [Patent Document 2] US10,233,353B2 Summary of the Invention [Problem to be solved by the invention]

[0010] The objective was to provide a coating composition with high solid content, which has good compatibility with other coating compositions in a multi-layer coating and can be used in an integrated paint process. Therefore, the objective was to prepare a coating composition comprising a polyester-polyurethane-poly(meth)acrylic hybrid dispersion with high solid content. A further objective is to provide a polyester-polyurethane-poly(meth)acrylic hybrid dispersion, which does not require a final stripping process, thereby reducing the time and cost of preparing this hybrid dispersion. Furthermore, the multi-layer coating obtained from the coating composition shows excellent appearance, especially excellent leveling. [Means for solving the problem]

[0011] This object has been solved by the subject matter of the present application and its preferred embodiments disclosed herein.

[0012] The first subject of the present invention is a polyester-polyurethane-poly(meth)acrylic hybrid dispersion, which can be prepared by the following steps: a. at least one carboxyl group-containing polyurethane having an acid value of more than 200 mgKOH / g to 400 mgKOH / g and at least one terminal carboxyl group; and esterifying at least one hydroxyl-containing polyester having a hydroxyl value of 50 mg KOH / g to 300 mg KOH / g. Obtaining polyester-polyurethane, followed by b. A step of polymerizing ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, by radical polymerization in the presence of the polyester-polyurethane of step (a) to obtain a poly(meth)acrylate. can be obtained by Here, one or more solvents are present and / or used during steps (a) and / or (b) and / or are added after step (b).

[0013] The present invention further provides a method for producing the polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention, comprising the steps of: a. at least one carboxyl group-containing polyurethane having an acid value of more than 200 mgKOH / g to 400 mgKOH / g and at least one terminal carboxyl group; and esterifying at least one hydroxyl-containing polyester having a hydroxyl value of 50 mg KOH / g to 300 mg KOH / g. Obtaining polyester-polyurethane, followed by b. A step of polymerizing ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, by radical polymerization in the presence of the polyester-polyurethane of step (a) to obtain a poly(meth)acrylate. This is due to The method further comprises the steps of: (a) preparing a mixture of a first solvent and a second solvent; (b) preparing a mixture of a first solvent and a second solvent; (c) preparing a mixture of a first solvent and a second solvent; (d) preparing a mixture of a first solvent and a second solvent; (e) preparing a mixture of a first solvent and a second solvent; (f) preparing a mixture of a first solvent and a second solvent; (g) preparing a mixture of a first solvent and a second solvent; (h) preparing a mixture of a first solvent and a second solvent

[0014] Another object of the present invention is a coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention.

[0015] Further objects of the present invention are coating layers formed from coating compositions comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersions of the present invention, and substrates thus coated.

[0016] Another object of the present invention is the use of a coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention in automotive coatings.

[0017] Yet another object of the present invention is to provide a method for producing a multi-layer coating comprising the steps of: a. applying one or more basecoat compositions to form one or more basecoat layers on a substrate, wherein at least one basecoat composition comprises a polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention; b. applying a clearcoat composition over one or more basecoat layers to form a clearcoat layer; c. curing one or more basecoat and clearcoat layers simultaneously, or curing one or more layers resulting from steps (a) and (b) separately before applying a subsequent coating layer, or curing all layers resulting from steps (a) and (b) separately. The method includes:

[0018] Preferred embodiments of the polyester-polyurethane-poly(meth)acrylic hybrid dispersions and coating compositions of the present invention are evident from the following description and from the dependent claims. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] definition First, the terms used in the context of the present invention are explained.

[0020] The term "hybrid dispersion" according to the present invention refers to a dispersion comprising a polyester-polyurethane and a poly(meth)acrylate, the polyester-polyurethane being physically mixed with the poly(meth)acrylate and / or being covalently bonded to the poly(meth)acrylate.

[0021] The expression "aqueous coating composition" is known to those skilled in the art. It refers to a coating composition in which the volatile portion of the coating composition is essentially based on water. "Aqueous" in the context of the present invention is therefore understood to mean that the coating composition preferably comprises a water fraction of at least 40% by weight, more preferably at least 50% by weight, most preferably at least 60% by weight, relative to the total amount of solvents (i.e. water and organic solvents) present in each case.

[0022] The term "aliphatic" is used according to the IUPAC definition, thereby including any acyclic or cyclic, saturated or unsaturated carbon compound except aromatic compounds.

[0023] The term "polymeric" describes a substance composed of several monomeric entities differing in degree of polymerization, molar mass and chain length. The monomeric entities may be identical or different. A "polymeric" substance in the context of the present invention also includes oligomeric substances.

[0024] A polyfunctional alcohol or isocyanate in the context of the present invention denotes a molecule having at least two functional groups and thus also includes difunctional alcohols or isocyanates.

[0025] The term "(meth)acrylic" refers to a material that contains methacrylate and / or methacrylic acid and / or acrylate and / or acrylic acid.

[0026] Polyester-polyurethane-poly(meth)acrylic hybrid dispersion The polyester-polyurethane-poly(meth)acrylic hybrid dispersion can be prepared by the following steps: a. at least one carboxyl group-containing polyurethane having an acid value of more than 200 mgKOH / g to 400 mgKOH / g and at least one terminal carboxyl group; and esterifying at least one hydroxyl-containing polyester having a hydroxyl value of 50 mg KOH / g to 300 mg KOH / g. Obtaining polyester-polyurethane, followed by b. A step of polymerizing ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, by radical polymerization in the presence of the polyester-polyurethane of step (a) to obtain a poly(meth)acrylate. can be obtained by Here, one or more solvents are present and / or used during steps (a) and / or (b) and / or are added after step (b).

[0027] The ethylenically unsaturated monomer in step (b) is polymerized to obtain a poly(meth)acrylate in the presence of the polyester-polyurethane obtained in step (a). Thus, the polyester-polyurethane in step (a) can be physically mixed with the poly(meth)acrylate in step (b) and / or can be covalently bonded to the poly(meth)acrylate in step (b). The poly(meth)acrylate in step (b) can be covalently bonded to the polyester-polyurethane in step (a), for example, when the polyester-polyurethane in step (a) contains ethylenically unsaturated groups and / or when the radical formation in the polyester-polyurethane in step (a) occurs by elimination of hydrogen, so that the ethylenically unsaturated (meth)acrylic monomer is attached to the polyester-polyurethane. Thus, there is no better way to represent the polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention than the way it is obtained.

[0028] The polyester-polyurethane-poly(meth)acrylic hybrid dispersion can be obtained by the following reaction steps (a) and (b).

[0029] Process a The polyester-polyurethane is obtained by esterifying at least one carboxyl-containing polyurethane having an acid value of more than 200 mgKOH / g to 400 mgKOH / g and at least one terminal carboxyl group with at least one hydroxyl-containing polyester having a hydroxyl value of 50 mgKOH / g to 300 mgKOH / g.

[0030] i. Polyurethane synthesis At least one polyurethane is synthesized by reacting one or more diisocyanates, one or more diols, and one or more carboxyl-containing and / or carboxyl-forming monomers.

[0031] The diols can be saturated or ethylenically unsaturated, more preferably saturated, and the saturated or ethylenically unsaturated diols can be substituted or unsubstituted. The diols can be aromatic or aliphatic, more preferably aliphatic. The aliphatic diols can be linear, branched or cyclic, preferably having 2-40 carbon atoms, more preferably 2-20 carbon atoms, even more preferably 2-16 carbon atoms, and most preferably 4-10 carbon atoms. Preferably, at least one diol is substituted, more preferably the substituted diol comprises one or more carboxyl group(s).

[0032] Examples of suitable saturated monomeric diols are ethylene glycol, neopentyl glycol, tripropylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 1,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, 2,2-bis(4-hydroxy-cyclohexyl)-propane, dimethylolpropionic acid, and dimethylolbutyric acid. The saturated monomeric diol is preferably ethylene glycol and / or dimethylolpropionic acid.

[0033] The ethylenically unsaturated diol preferably contains at least one allyl, vinyl, acrylic or methacrylic group. Examples of ethylenically unsaturated monomeric diols are trimethylolpropane monoallyl ether and pentaerythritol diallyl ether.

[0034] Preferably, the one or more diols are ethylene glycol and / or dimethylolpropionic acid.

[0035] Polyurethanes are synthesized by reacting at least one diol with one or more diisocyanates. The one or more diisocyanates can be aromatic or aliphatic, more preferably aliphatic. The aliphatic diisocyanates can be linear or cyclic, more preferably cyclic.

[0036] Suitable examples of the alicyclic diisocyanate are isophorone diisocyanate (=5-isocyanato-1-isocyanatomethyl-1,3,3-trimethylcyclohexane), 5-isocyanato-1-(2-isocyanatoeth-1-yl)-1,3,3-trimethylcyclohexane, 5-isocyanato-1-(3-isocyanatoprop-1-yl)-1,3,3-trimethylcyclohexane, 5-isocyanato-(4-isocyanatobut-1-yl)-1,3,3-trimethylcyclohexane, 1-isocyanato-2-(3-isocyanatoprop-1-yl) ... isocyanato-2-(2-isocyanatoeth-1-yl)cyclohexane, 1-isocyanato-2-(4-isocyanatobut-1-yl)cyclohexane, 1,2-diisocyanatocyclobutane, 1,3-diisocyanatocyclobutane, 1,2-diisocyanatocyclopentane, 1,3-diisocyanatocyclopentane, 1,2-diisocyanatocyclohexane, 1,3-diisocyanatocyclohexane, 1,4-diisocyanatocyclohexane, dicyclohexylmethane 2,4'-diisocyanate, and 4,4'-methylenebis(cyclohexylisocyanate).

[0037] Suitable examples of aromatic diisocyanates are 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane-4,4'-diisocyanate, p-phenylene diisocyanate, biphenyl diisocyanate, 3,3'-dimethyl-4,4'-diphenylene diisocyanate and tetramethylxylene diisocyanate.

[0038] Examples of linear aliphatic diisocyanates are ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexane-1,6-diisocyanate, heptamethylene diisocyanate, and 1,12-dodecane diisocyanate.

[0039] The one or more diisocyanates are preferably isophorone diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate) and / or tetramethylxylene diisocyanate.

[0040] One or more diisocyanates are preferably reacted with one or more diols in a solvent. The solvent is preferably an organic solvent. Examples of organic solvents suitable for the present invention include heterocyclic, aliphatic or aromatic hydrocarbons, monofunctional or polyfunctional alcohols, ethers, esters, ketones and amides, such as N-methylpyrrolidone, N-ethylpyrrolidone, dimethylformamide, toluene, xylene, butanol, ethyl glycol and butyl glycol and their acetates, butyl diglycol, diethylene glycol dimethyl ether, cyclohexanone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), acetone, isophorone, or mixtures thereof. Preferably, the organic solvent is methyl ethyl ketone (MEK).

[0041] The hydroxy-terminated polyurethane thus obtained can be synthesized in a one-step or two-step process. In the one-step process, one or more diisocyanates are reacted with one or more diols, and the diols are used in excess to prepare the hydroxy-terminated polyurethane. In the two-step process, one or more diisocyanates are reacted with one or more diols first. Subsequently, one or more diols are added to react the terminal NCO groups to prepare the hydroxy-terminated polyurethane. In the two-step process, the one or more diols reacting with the free isocyanate groups are preferably ethylene glycol.

[0042] The reaction of the one or more diisocyanates with the one or more diols is preferably carried out until less than 2% by weight, most preferably less than 1% by weight, of the NCO groups, based on the weight of the polyurethane, is converted, so that the polyurethane is substantially free of free NCO groups, the isocyanate content (NCO content) being determined by adding an excess of a 2% N,N-dibutylamine solution in xylene to a homogeneous solution of the sample in acetone / N-ethylpyrrolidone (1:1 vol.%) and by potentiometric back titration of the excess amine with 0.1 N hydrochloric acid according to DIN EN ISO3251, DIN EN ISO11909 and DIN EN ISO14886.

[0043] The hydroxy-terminated polyurethane thus obtained is reacted with one or more carboxyl-containing and / or carboxyl-forming group-containing monomers, preferably polycarboxylic acids and their anhydrides, preferably dicarboxylic acids, tricarboxylic acids and / or their anhydrides. The term "carboxyl-forming group" refers to the ability of a functional group to form a carboxyl group, preferably by hydrolysis of the corresponding anhydride or ester group.

[0044] The polycarboxylic acids and anhydrides may be aromatic or aliphatic, preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, even more preferably 4 to 12 carbon atoms, and most preferably 6 to 10 carbon atoms.

[0045] Examples of suitable aliphatic dicarboxylic acids are ethanedioic acid (oxalic acid), propanedioic acid (malonic acid), butanedioic acid (succinic acid), pentanedioic acid (glutaric acid), hexanedioic acid (adipic acid), heptanedioic acid (pimelic acid), octanedioic acid (suberic acid), nonanedioic acid (azelaic acid), decanedioic acid (sebacic acid), maleic acid, hexahydrophthalic acid and the respective anhydrides.

[0046] Examples of suitable aromatic dicarboxylic acids are 1,2-benzenedicarboxylic acid (phthalic acid), 1,3-benzenedicarboxylic acid (isophthalic acid) and 1,4-benzenedicarboxylic acid (terephthalic acid) and the respective anhydrides.

[0047] Suitable tricarboxylic acids are citric acid, isocitric acid, aconitic acid, propane-1,2,3-tricarboxylic acid, agaric acid, trimesic acid, trimellitic acid and the respective anhydrides.

[0048] Preferably, a hydroxy-terminated polyurethane is reacted with trimellitic anhydride.

[0049] The reaction is stopped at a certain acid value. The resulting polyurethane has at least one terminal carboxyl group, preferably the polyurethane has one or more terminal carboxyl groups and one or more carboxyl groups in the backbone, more preferably the polyurethane has at least two carboxyl groups per end, and most preferably the polyurethane has at least two carboxyl groups per end and one or more carboxyl groups in the backbone.

[0050] The resulting polyurethanes can be linear or branched, preferably linear.

[0051] The resulting polyurethane has an acid number of from greater than 200 mgKOH / g to 400 mgKOH / g, preferably from greater than 205 mgKOH / g to 350 mgKOH / g, more preferably from greater than 210 mgKOH / g to 300 mgKOH / g, even more preferably from greater than 220 mgKOH / g to 300 mgKOH / g, and most preferably from greater than 240 mgKOH / g to 300 mgKOH / g, measured according to DIN EN ISO 2114.

[0052] Preferably, the resulting polyurethane has a hydroxyl number in the range of 0 mg KOH / g to 50 mg KOH / g, more preferably 0 mg KOH / g to 46 mg KOH / g, even more preferably 0 mg KOH / g to 42 mg KOH / g, and most preferably 0 mg KOH / g to 40 mg KOH / g, as measured at room temperature in a tetrahydrofuran (THF) / dimethylformamide (DMF) solution in the presence of 4-dimethylaminopyridine as a catalyst using acetic anhydride according to R.-P. Krueger, R. Gnauck and R. Algeier (Plaste und Kautschuk, 20, 274 (1982)).

[0053] The polyurethane obtained is subsequently diluted with a solvent, preferably an organic solvent, to a solids content of preferably 60% to 80% by weight, more preferably 65% ​​to 75% by weight, the solids content being determined according to DIN EN ISO 3251 at 130° C. for 60 min using a 1.0 g weighing portion.

[0054] ii. Polyester synthesis At least one polyester is synthesized by reacting one or more polyols with one or more monomers selected from the group consisting of dicarboxylic acids and cyclic acid anhydrides. The at least one polyester can be saturated or ethylenically unsaturated.

[0055] The polyol can be saturated or ethylenically unsaturated, more preferably saturated, and the saturated or ethylenically unsaturated polyol can be substituted or unsubstituted. The polyol can be aromatic or aliphatic, more preferably aliphatic. The aliphatic polyol can be linear, branched or cyclic, preferably having 2 to 40 carbon atoms, more preferably 2 to 20 carbon atoms, even more preferably 2 to 16 carbon atoms, and most preferably 4 to 10 carbon atoms.

[0056] Examples of suitable saturated monomeric polyols are ethylene glycol, neopentyl glycol, tripropylene glycol, 1,2-propanediol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, 2,2-bis(4-hydroxy-cyclohexyl)propane, trimethylolpropane, trimethylolethane, trimethylolhexane, glycerol, 1,2,4-butanetriol, ditrimethylolpropane, pentaerythritol and dipentaerythritol.

[0057] The ethylenically unsaturated polyol preferably contains at least one allyl, vinyl, acrylic or methacrylic group. Examples of ethylenically unsaturated monomeric polyols are trimethylolpropane monoallyl ether and pentaerythritol diallyl ether.

[0058] Preferably, the one or more polyols are neopentyl glycol, tripropylene glycol, 1,6-hexanediol and / or trimethylolpropane.

[0059] The polyester is synthesized by reacting at least one polyol with one or more monomers selected from the group consisting of dicarboxylic acids, tricarboxylic acids, and cyclic acid anhydrides.

[0060] The dicarboxylic acid may be aromatic or aliphatic, preferably having 2 to 50 carbon atoms, more preferably 2 to 44 carbon atoms, even more preferably 4 to 44 carbon atoms, and most preferably 6 to 44 carbon atoms.

[0061] Examples of suitable aliphatic dicarboxylic acids are ethanedioic acid (oxalic acid), propanedioic acid (malonic acid), butanedioic acid (succinic acid), pentanedioic acid (glutaric acid), hexanedioic acid (adipic acid), heptanedioic acid (pimelic acid), octanedioic acid (suberic acid), nonanedioic acid (azelaic acid), decanedioic acid (sebacic acid), maleic acid and hexahydrophthalic acid. Preferably, hexanedioic acid (adipic acid) is used as the aliphatic dicarboxylic acid. Examples of suitable aromatic dicarboxylic acids are 1,2-benzenedicarboxylic acid (phthalic acid), 1,3-benzenedicarboxylic acid (isophthalic acid) and 1,4-benzenedicarboxylic acid (terephthalic acid).

[0062] A further possibility is to use dimer fatty acids as polycarboxylic acids. Dimer fatty acids are mixtures produced by oligomerization of unsaturated fatty acids. 12 ~C 22 Fatty acids are used as starting materials. Suitable dimeric fatty acids are, for example, Radiacid0970, Radiacid0971, Radiacid0972, Radiacid0975, Radiacid0976, Radiacid0977, Pripol1006, Pripol1009, Pripol1012 and Pripol1013, Empol1008, Empol1061 and Empol1062 (WO2015 / 028201A1).

[0063] Preferably, the dicarboxylic acid is aromatic, more preferably isophthalic acid.

[0064] Suitable tricarboxylic acids are citric acid, isocitric acid, aconitic acid, propane-1,2,3-tricarboxylic acid, agaric acid, trimesic acid and trimellitic acid.

[0065] The cyclic acid anhydrides preferably have from 2 to 40 carbon atoms, more preferably from 2 to 30 carbon atoms, even more preferably from 4 to 20 carbon atoms, and most preferably from 6 to 18 carbon atoms. The cyclic acid anhydrides can be saturated or ethylenically unsaturated.

[0066] Examples of suitable cyclic anhydrides are phthalic anhydride, trimellitic anhydride, maleic anhydride and its derivatives, and alkenylsuccinic anhydrides, such as tetrapropenylsuccinic anhydride. Preferably, the one or more cyclic anhydrides are phthalic anhydride, trimellitic anhydride and / or tetrapropenylsuccinic anhydride.

[0067] One or more polyols are reacted with one or more monomers selected from the group consisting of dicarboxylic acids and cyclic acid anhydrides at a temperature preferably between 200°C and 250°C, more preferably between 210°C and 240°C.

[0068] The hydroxyl number of the resulting polyester is 50 mg KOH / g to 300 mg KOH / g, preferably 60 to 280 mg KOH / g, more preferably 70 to 250 mg KOH / g, even more preferably 100 to 250 mg KOH / g, and most preferably 120 to 250 mg KOH / g, as measured at room temperature in a tetrahydrofuran (THF) / dimethylformamide (DMF) solution in the presence of 4-dimethylaminopyridine as a catalyst using acetic anhydride according to R.-P. Krueger, R. Gnauck and R. Algeier (Plaste und Kautschuk, 20, 274 (1982)).

[0069] Preferably, the acid number of the resulting polyester is less than 20 mg KOH / g, more preferably less than 18 mg KOH / g, even more preferably less than 15 mg KOH / g, most preferably less than 12 mg KOH / g, measured according to DIN EN ISO2114.

[0070] The resulting polyesters can be linear or branched, preferably branched.

[0071] iii. Synthesis of polyester-polyurethane (PEU) or polyester-polyurethane dispersion (PEUD) The polyester and polyurethane are mixed and the temperature is carefully raised, under reduced pressure, preferably to 120°C-180°C, more preferably to 130°C-170°C. Preferably the pressure is 15mbar-80mbar, more preferably 15mbar-70mbar. The process can be monitored by titration and viscosity measurement at 140°C. The reaction is stopped when the acid number preferably reaches 10mgKOH / g-50mgKOH / g, more preferably 15mgKOH / g-45mgKOH / g, most preferably 20mgKOH / g-40mgKOH / g and / or when the viscosity preferably reaches 1000mPa*s-2400mPa*s, more preferably 1200mPa*s-2200mPa*s, most preferably 1300mPa*s-2000mPa*s, measured at a temperature of 1250s using a CAP2000H viscometer equipped with spindle 03 at 140°C. -1 The shear rate is measured according to DIN EN ISO 2884-1. The temperature is preferably reduced to a temperature between 60°C and 120°C, more preferably between 70°C and 115°C.

[0072] The polyester-polyurethane may be reacted with at least one ethylenically unsaturated monomer as outlined in step b, with or without the addition of one or more solvents after neutralization with a neutralizing agent.

[0073] Suitable examples of neutralizing agents are alkylalkanolamines such as dimethylethanolamine (DMEA), diethylethanolamine (DEEA), methyldiethanolamine (MDEA) or methylethanolamine (NMEA). Preferably, dimethylethanolamine is used as the neutralizing agent.

[0074] One or more solvents may be present and / or used during steps (a) and / or (b) and / or added after step (b), the solvent may be present during the preparation of the polyester and / or polyurethane and / or during step (a) and / or during the esterification of the polyester and polyurethane in step (b), the solvent may be present before, during and / or after the addition of the (meth)acrylic monomer and / or the radical initiator. The at least one polyurethane and the at least one polyester in step (a) may be esterified in the presence of one or more solvents to obtain a polyester-polyurethane dispersion.

[0075] The solvent can be water or an organic solvent. Preferably, water is added to adjust the solids content and produce the aqueous polyester-polyurethane dispersion.

[0076] Preferably, the synthesized polyester-polyurethane dispersion has a solids content of ≧40% by weight, more preferably ≧42% by weight, even more preferably ≧45% by weight, most preferably ≧48% by weight, measured according to DIN EN ISO 3251 at 130° C. for 60 min using a 1.0 g weighing portion.

[0077] Preferably, the polyester-polyurethane dispersion is subjected to a rheometer test at a temperature of 23° C. for 1000 s using a Rheolab QC rotational rheometer equipped with a cc27 cylinder. -1 The viscosity of the composition is preferably from 100 mPa*s to 300 mPa*s, more preferably from 110 mPa*s to 290 mPa*s, even more preferably from 120 mPa*s to 280 mPa*s, and most preferably from 130 mPa*s to 260 mPa*s, measured according to DIN 53019-1 using a shear rate of 100 mPa*s to 300 mPa*s, more preferably from 110 mPa*s to 290 mPa*s, even more preferably from 120 mPa*s to 280 mPa*s, and most preferably from 130 mPa*s to 260 mPa*s.

[0078] Preferably, the polyester-polyurethane has an acid number in the range of 10 mgKOH / g to 50 mgKOH / g, more preferably 15 mgKOH / g to 45 mgKOH / g, even more preferably 20 mgKOH / g to 40 mgKOH / g, most preferably 25 mgKOH / g to 35 mgKOH / g, measured according to DIN EN ISO2114.

[0079] Preferably, the polyester-polyurethane has a particle size of 50 nm to 200 nm, more preferably 70 nm to 180 nm, even more preferably 80 nm to 150 nm, and most preferably 90 nm to 130 nm, as determined by measuring the hydrodynamic volume / hydrodynamic radius of the dispersed particles using Photon Correlation Spectroscopy (PCS).

[0080] Preferably, the polyester-polyurethane has a number average molecular weight (M) of 1,000 g / mol to 3,500 g / mol, more preferably 1,200 g / mol to 3,200 g / mol, even more preferably 1,500 g / mol to 3,000 g / mol, and most preferably 1,800 g / mol to 2,800 g / mol. n ) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0081] Preferably, the polyester-polyurethane has a weight average molecular weight (M) of 6,000 g / mol to 50,000 g / mol, more preferably 7,000 g / mol to 48,000 g / mol, even more preferably 8,000 g / mol to 46,000 g / mol, and most preferably 9,000 g / mol to 43,000 g / mol. w ) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0082] Process b In the presence of the polyester-polyurethane of step (a), ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, are polymerized by radical polymerization to obtain a poly(meth)acrylate.

[0083] The ethylenically unsaturated monomer of step (b) is added to the polyester-polyurethane dispersion or neat polyester-polyurethane of step (a) prior to the addition of the radical initiator, simultaneously with the radical initiator and / or after the radical initiator. If the ethylenically unsaturated monomer is added to the polyester-polyurethane of step (a) prior to the addition of the radical initiator, the ethylenically unsaturated monomer and the polyester-polyurethane of step (a) are preferably incubated for at least 10 minutes, more preferably at least 30 minutes, even more preferably at least 60 minutes, most preferably at least 2 hours, such as at least 4 hours, preferably at a temperature of 20°C to 30°C.

[0084] Before or after the addition of the (meth)acrylic monomer or the radical initiator, a solvent can be added to the polyester-polyurethane to obtain a polyester-polyurethane dispersion containing the (meth)acrylic monomer. The solvent can be water or an organic solvent. Preferably, water is added to adjust the solid content and produce an aqueous polyester-polyurethane dispersion.

[0085] The ethylenically unsaturated monomers may be cyclic, linear or branched alkyl (meth)acrylates, hydroxyalkyl esters of (meth)acrylic acid, (meth)acrylic acid and / or vinyl aromatic hydrocarbons, the ethylenically unsaturated monomers may be monoethylenically unsaturated or poly-ethylenically unsaturated, the functionality of the poly-ethylenically unsaturated monomers may range from 2 to 5. Preferably, the poly-ethylenically unsaturated monomers are di-ethylenically unsaturated or tri-ethylenically unsaturated, most preferably di-ethylenically unsaturated. Preferably, the ethylenically unsaturated monomers are monoethylenically unsaturated monomers or a mixture of monoethylenically unsaturated and di-ethylenically unsaturated monomers.

[0086] Suitable cyclic, linear or branched alkyl (meth)acrylates are cyclohexyl (meth)acrylate and alkyl (meth)acrylates having up to 20 carbon atoms. Preferred monoethylenically unsaturated alkyl (meth)acrylates are t-butyl acrylate, n-butyl acrylate, n-butyl methacrylate, methyl methacrylate, ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, most preferably t-butyl acrylate, n-butyl acrylate, n-butyl methacrylate and ethylhexyl methacrylate.

[0087] Suitable hydroxyalkyl esters of (meth)acrylic acid are hydroxyalkyl esters of (meth)acrylic acid in which the hydroxyalkyl group contains not more than 6 carbon atoms, preferably 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate.

[0088] Suitable di-ethylenically unsaturated monomers are ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, 1,2-propanediol di(meth)acrylate, 1,3-propanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, allyl (meth)acrylate and divinylbenzene.Suitable poly-ethylenically unsaturated monomers are trimethylolpropane tri(meth)acrylate, pentaerythritol tri- and tetraacrylate, tris(2-hydroxyethyl)isocyanurate triacrylate and ethoxylated 3-trimethylolpropane triacrylate.

[0089] Suitable vinyl aromatic hydrocarbons are styrene, alpha-alkylstyrenes, vinyltoluenes, (meth)acrylamides and (meth)acrylonitrile.

[0090] Preferably, the ethylenically unsaturated monomer in step (b) is an alkyl (meth)acrylate, more preferably t-butyl acrylate, n-butyl acrylate, n-butyl methacrylate and ethylhexyl methacrylate.

[0091] The ethylenically unsaturated monomer of step (b) is added to the polyester-polyurethane of step (a) either prior to the addition of the radical initiator or simultaneously with the radical initiator.

[0092] To start the radical polymerization, water-soluble or water-insoluble initiators can be used.Examples of water-soluble initiators are hydrogen peroxide, peroxydisulfates, such as sodium, potassium and ammonium peroxydisulfates, the ammonium salt of 4,4'-azobis(4-cyanopentanoic acid), 2,2'-azobis(2-methyl-N-1,1-bis(hydroxymethyl)ethyl)propionamide, 2,2'-azobis(2-methyl-N-2-hydroxyethyl)propionamide).Preferably, ammonium peroxydisulfate (APS) is used as the water-soluble initiator.

[0093] Examples of water-insoluble initiators are tert.butyl-peroxy-2-ethylhexanol, tert.butyl peroxypivalate and dibenzoyl peroxide. Preferably, tert.butyl-peroxy-2-ethylhexanol is used as the water-insoluble initiator. Preferably, the radical polymerization is initiated by a water insoluble initiator, more preferably tert.butyl-peroxy-2-ethylhexanol.

[0094] The radical initiator generates radicals in the ethylenically unsaturated polyester-polyurethane polymer and / or in the ethylenically unsaturated monomer, thereby obtaining a poly(meth)acrylate, which can be physically mixed with the polyester-polyurethane of step (a) or can be covalently bonded to the polyester-polyurethane of step (a). For example, the poly(meth)acrylate can be covalently bonded to the polyester-polyurethane of step (a) by forming a graft polymer formed by radical copolymerization of the ethylenically unsaturated monomer with the ethylenically unsaturated group in the backbone of the polyester-polyurethane of step (a) and / or by abstraction of H on the backbone of the polyester-polyurethane of step (a).

[0095] Preferably, the solids content of the resulting polyester-polyurethane-poly(meth)acrylic hybrid dispersion is ≧40% by weight, more preferably ≧42% by weight, even more preferably ≧43% by weight, even more preferably ≧44% by weight, even more preferably ≧48% by weight, most preferably ≧50% by weight, measured according to DIN EN ISO 3251 at 130° C. for 60 minutes using a 1.0 g weighing portion.

[0096] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid has a glass transition temperature of -50°C to +50°C, more preferably -48°C to 40°C, even more preferably -45°C to 35°C, and most preferably -45°C to 30°C, measured according to DIN-EN-ISO 11357-1 and -2.

[0097] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrids prepared with one or more monoethylenically unsaturated monomers have a number average molecular weight (M) of 2,500 g / mol to 5,000 g / mol, more preferably 2,700 g / mol to 4,800 g / mol, and most preferably 3,000 g / mol to 4,500 g / mol. n ) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0098] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrids prepared with one or more monoethylenically unsaturated monomers have a weight average molecular weight (M) of 25,000 g / mol to 550,000 g / mol, more preferably 30,000 g / mol to 500,000 g / mol, even more preferably 50,000 g / mol to 450,000 g / mol, and most preferably 100,000 g / mol to 400,000 g / mol. w) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0099] The number average molecular weight (M) of polyester-polyurethane-poly(meth)acrylic hybrids prepared with at least one poly-ethylenically unsaturated monomer, preferably at least one di-ethylenically unsaturated monomer, is n ) and mass average molecular weight (M w ) is the number average molecular weight (M) as described in the preceding two paragraphs of this specification. n ) and mass average molecular weight (M w ) may be even higher.

[0100] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid has an acid number of 5 mgKOH / g to 50 mgKOH / g, more preferably 10 mgKOH / g to 45 mgKOH / g, even more preferably 15 mgKOH / g to 40 mgKOH / g, even more preferably 15 mgKOH / g to 35 mgKOH / g, and most preferably 15 mgKOH / g to 30 mgKOH / g, measured according to DIN EN ISO2114.

[0101] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion is subjected to a rheological test at a temperature of 23° C. for 1000 s using a Rheolab QC rotational rheometer. -1 The viscosity of the composition is from 5 mPa*s to 3000 mPa*s, more preferably from 10 mPa*s to 2500 mPa*s, even more preferably from 10 mPa*s to 1000 mPa*s, even more preferably from 10 mPa*s to 500 mPa*s, and even more preferably from 10 mPa*s to 200 mPa*s, measured according to DIN 53019-1 using a shear rate of 1000 mPa*s to 500 mPa*s.

[0102] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion has a particle size of 50 nm to 400 nm, more preferably 70 nm to 300 nm, even more preferably 100 nm to 250 nm, and most preferably 120 nm to 220 nm, as measured by measuring the hydrodynamic volume / hydrodynamic radius of the dispersed particles using Photon Correlation Spectroscopy (PCS).

[0103] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion is a mixture of 45-90% by mass of the polyester-polyurethane of step (a) and 10-55% by mass of the poly(meth)acrylate obtainable by step (b), more preferably 50-90% by mass of the polyester-polyurethane of step (a) and 10-50% by mass of the poly(meth)acrylate obtainable by step (b), even more preferably 55-90% by mass of the polyester-polyurethane of step (a) and 10-45% by mass of the poly(meth)acrylate obtainable by step (b). ), even more preferably 60-90% by weight of the polyester-polyurethane of step (a) and 10-40% by weight of the poly(meth)acrylate obtainable by step (b), most preferably 65-90% by weight of the polyester-polyurethane of step (a) and 10-35% by weight of the poly(meth)acrylate obtainable by step (b), these weight percentages being relative to the solids content of the polyester-polyurethane-poly(meth)acrylic hybrid dispersion.

[0104] Method for producing polyester-polyurethane-poly(meth)acrylic hybrid dispersion The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention can be obtained by, in a first step (a), esterifying at least one carboxyl-containing polyurethane having an acid value of more than 200 mgKOH / g to 400 mgKOH / g and at least one or more terminal carboxyl groups with at least one hydroxyl-containing polyester having a hydroxyl value of 50 mgKOH / g to 300 mgKOH / g to obtain a polyester-polyurethane, followed in a second step (b) by radical polymerization of ethylenically unsaturated monomers, including at least one (meth)acrylic monomer, in the presence of the polyester-polyurethane of step (a) to obtain a poly(meth)acrylate, wherein one or more solvents are present and / or used during steps (a) and / or (b) and / or added after step (b).

[0105] Step (a): Preparation of polyester-polyurethane (PEU) or polyester-polyurethane dispersion (PEUD) The polyester-polyurethane of the polyester-polyurethane-poly(meth)acrylic dispersion is prepared by esterifying at least one carboxyl-containing polyurethane (the at least one polyurethane having an acid value of more than 200 mg KOH / g to 400 mg KOH / g and at least one or more terminal carboxyl groups) with at least one hydroxyl-containing polyester (the polyester having a hydroxyl value of 50 mg KOH / g to 300 mg KOH / g).

[0106] Polyurethane is synthesized by reacting one or more diisocyanates, one or more diols, and one or more carboxyl-containing and / or carboxyl-forming monomers, which are the same as the diols, diisocyanates, and carboxyl-containing and / or carboxyl-forming monomers described above in item i. Synthesis of Polyurethane.

[0107] The reaction of the one or more diisocyanates with the one or more diols is preferably carried out until less than 2% by weight, most preferably less than 1% by weight, of the NCO groups, based on the weight of the polyurethane, is converted, so that the polyurethane is substantially free of free NCO groups.

[0108] The hydroxy-terminated polyurethane thus obtained is reacted with one or more carboxyl-containing and / or carboxyl-forming group-containing monomers, which are preferably polycarboxylic acids and their anhydrides, preferably dicarboxylic acids, tricarboxylic acids and / or their anhydrides. Suitable dicarboxylic acids, tricarboxylic acids and their anhydrides are given above.

[0109] Preferably, a hydroxy-terminated polyurethane is reacted with trimellitic anhydride.

[0110] The reaction is stopped at a certain acid value. The resulting polyurethane has at least one terminal carboxyl group, preferably the polyurethane has one or more terminal carboxyl groups and one or more carboxyl groups in the backbone, more preferably the polyurethane has at least two carboxyl groups per end, and most preferably the polyurethane has at least two carboxyl groups per end and one or more carboxyl groups in the backbone.

[0111] The resulting polyurethanes can be linear or branched, preferably linear.

[0112] The resulting polyurethane has an acid number of from greater than 200 mgKOH / g to 400 mgKOH / g, preferably from greater than 205 mgKOH / g to 350 mgKOH / g, more preferably from greater than 210 mgKOH / g to 300 mgKOH / g, even more preferably from greater than 220 mgKOH / g to 300 mgKOH / g, and most preferably from greater than 240 mgKOH / g to 300 mgKOH / g, measured according to DIN EN ISO 2114.

[0113] The polyurethane obtained is subsequently diluted with a solvent, preferably an organic solvent, to a solids content of preferably 60% to 80% by weight, more preferably 65% ​​to 75% by weight, the solids content being determined according to DIN EN ISO 3251 at 130° C. for 60 min using a 1.0 g weighing portion.

[0114] At least one polyester is synthesized by reacting one or more polyols with one or more monomers selected from the group consisting of dicarboxylic acids and cyclic acid anhydrides, the polyols and the one or more monomers selected from the group consisting of dicarboxylic acids and cyclic acid anhydrides being the same as the polyols and the monomers selected from the group consisting of dicarboxylic acids and anhydrides described above in item ii. Synthesis of polyesters.

[0115] One or more polyols are reacted with one or more monomers selected from the group consisting of dicarboxylic acids and cyclic acid anhydrides at a temperature preferably between 200°C and 250°C, more preferably between 210°C and 240°C.

[0116] The resulting polyesters can be linear or branched, preferably branched.

[0117] The hydroxyl number of the resulting polyester is 50 mg KOH / g to 300 mg KOH / g, preferably 60 to 280 mg KOH / g, more preferably 70 to 250 mg KOH / g, even more preferably 100 to 250 mg KOH / g, and most preferably 120 to 250 mg KOH / g, as measured at room temperature in a tetrahydrofuran (THF) / dimethylformamide (DMF) solution in the presence of 4-dimethylaminopyridine as a catalyst using acetic anhydride according to R.-P. Krueger, R. Gnauck and R. Algeier (Plaste und Kautschuk, 20, 274 (1982)).

[0118] The acid number of the resulting polyester is less than 20 mg KOH / g, preferably less than 18 mg KOH / g, more preferably less than 15 mg KOH / g, most preferably less than 12 mg KOH / g, determined according to DIN EN ISO2114.

[0119] The polyester and polyurethane are mixed and the temperature is carefully raised, under reduced pressure, preferably to 120°C-180°C, more preferably to 130°C-170°C. Preferably the pressure is 15mbar-80mbar, more preferably 15mbar-70mbar. The process is monitored by titration and viscosity measurement at 140°C. Preferably the reaction is stopped when the acid number reaches preferably 10-50mgKOH / g, more preferably 15-45mgKOH / g, most preferably 20mgKOH / g-40mgKOH / g and / or when the viscosity reaches preferably 1000mPa*s-2400mPa*s, more preferably 1200mPa*s-2200mPa*s, most preferably 1300mPa*s-2000mPa*s, measured at a temperature of 1250s using a CAP2000H viscometer equipped with spindle 03 at 140°C. -1 It is determined according to DIN EN ISO 2884-1 using a shear rate of 100 MPa.

[0120] The temperature is preferably reduced to a temperature of 60°C to 120°C, more preferably 70°C to 115°C.

[0121] The polyester-polyurethane may be reacted with at least one ethylenically unsaturated monomer as outlined in step (b) with or without the addition of one or more solvents after neutralization with a neutralizing agent.

[0122] Suitable examples of neutralizing agents are alkylalkanolamines such as dimethylethanolamine (DMEA), diethylethanolamine (DEEA), methyldiethanolamine (MDEA) or methylethanolamine (NMEA). Preferably, dimethylethanolamine is used as the neutralizing agent.

[0123] One or more solvents may be present and / or used during steps (a) and / or (b) and / or added after step (b), the solvent may be present during the preparation of the polyester and / or polyurethane and / or during step (a) and / or during the esterification of the polyester and polyurethane in step (b), the solvent may be present before, during and / or after the addition of the (meth)acrylic monomer and / or the radical initiator. The at least one polyurethane and the at least one polyester in step (a) may be esterified in the presence of one or more solvents to obtain a polyester-polyurethane dispersion.

[0124] Preferably, a solvent is added to adjust the solid content of the polyester-polyurethane dispersion. The solvent can be water or an organic solvent. Preferably, water is added to adjust the solid content and produce an aqueous polyester-polyurethane dispersion.

[0125] Preferably, the synthesized polyester-polyurethane dispersion has a solids content of ≧40% by weight, more preferably ≧42% by weight, most preferably ≧45% by weight, measured according to DIN EN ISO 3251 at 130° C. for 60 min using a 1.0 g weighing portion.

[0126] Preferably, the polyester-polyurethane dispersion is subjected to a rheometer test at a temperature of 23° C. for 1000 s using a Rheolab QC rotational rheometer equipped with a cc27 cylinder. -1 The viscosity of the composition is preferably from 100 mPa*s to 300 mPa*s, more preferably from 110 mPa*s to 290 mPa*s, even more preferably from 120 mPa*s to 280 mPa*s, and most preferably from 130 mPa*s to 260 mPa*s, measured according to DIN 53019-1 using a shear rate of 100 mPa*s to 300 mPa*s, more preferably from 110 mPa*s to 290 mPa*s, even more preferably from 120 mPa*s to 280 mPa*s, and most preferably from 130 mPa*s to 260 mPa*s.

[0127] Preferably, the polyester-polyurethane has an acid number in the range of 10 mgKOH / g to 50 mgKOH / g, more preferably 15 mgKOH / g to 45 mgKOH / g, even more preferably 20 mgKOH / g to 40 mgKOH / g, most preferably 25 mgKOH / g to 35 mgKOH / g, measured according to DIN EN ISO2114.

[0128] Preferably, the polyester-polyurethane has a particle size of 50 nm to 200 nm, more preferably 70 nm to 180 nm, even more preferably 80 nm to 150 nm, and most preferably 90 nm to 130 nm, as determined by measuring the hydrodynamic volume / hydrodynamic radius of the dispersed particles using Photon Correlation Spectroscopy (PCS).

[0129] Preferably, the polyester-polyurethane has a number average molecular weight (M) of 1,000 g / mol to 3,500 g / mol, more preferably 1,200 g / mol to 3,200 g / mol, even more preferably 1,500 g / mol to 3,000 g / mol, and most preferably 1,800 g / mol to 2,800 g / mol. n ) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0130] Preferably, the polyester-polyurethane has a weight average molecular weight (M) of 6,000 g / mol to 50,000 g / mol, more preferably 7,000 g / mol to 48,000 g / mol, even more preferably 8,000 g / mol to 46,000 g / mol, and most preferably 9,000 g / mol to 43,000 g / mol. w ) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0131] Step (b): Preparation of poly(meth)acrylate In the presence of the polyester-polyurethane of step (a), ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, are polymerized by radical polymerization to obtain a poly(meth)acrylate.

[0132] The ethylenically unsaturated monomer can be added to the neutralized and / or diluted polyester-polyurethane dispersion or to the undiluted polyester-polyurethane. The ethylenically unsaturated monomer of step (b) is added to the polyester-polyurethane of step (a) before the addition of the radical initiator or simultaneously with the radical initiator. When the ethylenically unsaturated monomer is added to the polyester-polyurethane of step (a) before the addition of the radical initiator, the ethylenically unsaturated monomer and the polyester-polyurethane of step (a) are preferably incubated for at least 10 minutes, more preferably at least 30 minutes, even more preferably at least 60 minutes, most preferably at least 2 hours, for example at least 4 hours, preferably at a temperature of 20°C to 30°C.

[0133] Before or after the addition of the (meth)acrylic monomer or the radical initiator, a solvent can be added to the polyester-polyurethane to obtain a polyester-polyurethane dispersion containing the (meth)acrylic monomer. The solvent can be water or an organic solvent. Preferably, water is added to adjust the solid content and produce an aqueous polyester-polyurethane dispersion.

[0134] Suitable ethylenically unsaturated monomers are set forth above. Preferably, monoethylenically unsaturated alkyl (meth)acrylate monomers are polymerized in step (b), more preferably t-butyl acrylate, n-butyl acrylate, n-butyl methacrylate and ethylhexyl methacrylate.

[0135] Water-soluble or water-insoluble initiators can be used to initiate radical polymerization.Examples of water-soluble initiators are hydrogen peroxide, peroxydisulfates, such as sodium, potassium and ammonium peroxydisulfates, the ammonium salt of 4,4'-azobis(4-cyanopentanoic acid), 2,2'-azobis(2-methyl-N-1,1-bis(hydroxymethyl)ethyl)propionamide, 2,2'-azobis(2-methyl-N-(2-hydroxyethyl)propionamide).Preferably, ammonium peroxydisulfate (APS) is used as the water-soluble initiator.

[0136] Examples of water-insoluble initiators are tert.butyl-peroxy-2-ethylhexanol, tert.butyl peroxypivalate and dibenzoyl peroxide. Preferably, tert.butyl-peroxy-2-ethylhexanol is used as the water-insoluble initiator.

[0137] Preferably, the radical polymerization is initiated by a water insoluble initiator, more preferably tert.butyl-peroxy-2-ethylhexanol.

[0138] The radical initiator generates radicals within the ethylenically unsaturated polyester-polyurethane polymer and / or within the ethylenically unsaturated monomers.

[0139] Thereby, a poly(meth)acrylate is obtained, which can be physically mixed with the polyester-polyurethane of step (a) or can be covalently bonded to the polyester-polyurethane of step (a), for example, by the formation of a graft polymer formed by radical copolymerization of an ethylenically unsaturated monomer with an ethylenically unsaturated group in the backbone of the polyester-polyurethane of step (a) and / or by abstraction of H on the backbone of the polyester-polyurethane of step (a).

[0140] Preferably, the solids content of the resulting polyester-polyurethane-poly(meth)acrylic hybrid dispersion is ≧40% by weight, more preferably ≧42% by weight, even more preferably ≧43% by weight, even more preferably ≧44% by weight, even more preferably ≧48% by weight, most preferably ≧50% by weight, measured according to DIN EN ISO 3251 at 130° C. for 60 minutes using a 1.0 g weighing portion.

[0141] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid has a glass transition temperature of -50°C to +50°C, more preferably -48°C to 40°C, even more preferably -45°C to 35°C, and most preferably -45°C to 30°C, measured according to DIN-EN-ISO 11357-1 and -2.

[0142] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrids prepared with one or more monoethylenically unsaturated monomers have a number average molecular weight (M) of 2,500 g / mol to 5,000 g / mol, more preferably 2,700 g / mol to 4,800 g / mol, and most preferably 3,000 g / mol to 4,500 g / mol. n ) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0143] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrids prepared with one or more monoethylenically unsaturated monomers have a weight average molecular weight (M) of 25,000 g / mol to 550,000 g / mol, more preferably 30,000 g / mol to 500,000 g / mol, even more preferably 50,000 g / mol to 450,000 g / mol, and most preferably 100,000 g / mol to 400,000 g / mol. w) as determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0144] The number average molecular weight (M) of polyester-polyurethane-poly(meth)acrylic hybrids prepared with at least one poly-ethylenically unsaturated monomer, preferably at least one di-ethylenically unsaturated monomer, is n ) and mass average molecular weight (M w ) is the number average molecular weight (M) as described in the preceding two paragraphs of this specification. n ) and mass average molecular weight (M w ) may be even higher.

[0145] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid has an acid number of 5 mgKOH / g to 50 mgKOH / g, more preferably 10 mgKOH / g to 45 mgKOH / g, even more preferably 15 mgKOH / g to 40 mgKOH / g, even more preferably 15 mgKOH / g to 35 mgKOH / g, and most preferably 15 mgKOH / g to 30 mgKOH / g, measured according to DIN EN ISO2114.

[0146] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion is subjected to a rheometer test at a temperature of 23° C. for 1000 s using a Rheolab QC rotational rheometer equipped with a cc27 cylinder. -1 The viscosity of the composition is from 5 mPa*s to 3000 mPa*s, more preferably from 10 mPa*s to 2500 mPa*s, even more preferably from 10 mPa*s to 1000 mPa*s, even more preferably from 10 mPa*s to 500 mPa*s, and even more preferably from 10 mPa*s to 200 mPa*s, measured according to DIN 53019-1 using a shear rate of 1000 mPa*s to 500 mPa*s.

[0147] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion has a particle size of 50 nm to 400 nm, more preferably 70 nm to 300 nm, even more preferably 100 nm to 250 nm, and most preferably 120 nm to 220 nm, as measured by measuring the hydrodynamic volume / hydrodynamic radius of the dispersed particles using Photon Correlation Spectroscopy (PCS).

[0148] Preferably, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion comprises 45-90% by weight of the polyester-polyurethane of step (a) and 10-55% by weight of the poly(meth)acrylate of step (b), more preferably 50-90% by weight of the polyester-polyurethane of step (a) and 10-50% by weight of the poly(meth)acrylate of step (b), even more preferably 55-90% by weight of the polyester-polyurethane of step (a) and 10-45% by weight of the poly(meth)acrylate of step (b), even more preferably 60-90% by weight of the polyester-polyurethane of step (a) and 10-40% by weight of the poly(meth)acrylate of step (b), most preferably 65-90% by weight of the polyester-polyurethane of step (a) and 10-35% by weight of the poly(meth)acrylate of step (b), these weight percentages being based on the solid content of the polyester-polyurethane-poly(meth)acrylic hybrid dispersion.

[0149] Methods of using the polyester-polyurethane-poly(meth)acrylic hybrid dispersions according to the present invention The polyester-polyurethane-poly(meth)acrylic hybrid dispersions according to the invention are suitable for a number of applications: The polyester-polyurethane-poly(meth)acrylic hybrid dispersions according to the invention can be used, inter alia, in many fields of coatings, in particular automotive coatings.

[0150] In particular, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention can be used in base coat compositions or filler coating compositions, more preferably in base coat compositions or filler coating compositions in automotive coatings. The coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention can be used to form a base coat layer on an untreated substrate or a pretreated substrate. Furthermore, the coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention can be used to form a second base coat layer on a first base coat layer.

[0151] Coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention Another object of the present invention is a coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the invention.

[0152] The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention can be used as a binder in any coating composition, especially in basecoat compositions.

[0153] The polyester-polyurethane-poly(meth)acrylic hybrid dispersions according to the present invention can be used in any liquid coating composition, which can be aqueous or solvent-based, preferably aqueous coating compositions.

[0154] The coating compositions comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersions according to the invention can be used to form one or more layers in multi-layer coatings, preferably on untreated or pre-treated substrates, in particular on automotive bodies or parts thereof.

[0155] The coating composition is preferably thermosetting. A thermosetting coating composition comprises, besides the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the invention, further materials, such as one or more further binders (A1) and / or one or more commonly used coating additives (A2) and / or one or more pigments and / or fillers (A3) and / or one or more solvents (A4), as additional components (A).

[0156] Further Binders (A1) In addition to the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the invention, further polymers selected from the group consisting of polyurethanes, polyureas, polyesters, polyamides, poly(meth)acrylates and / or copolymers of structural units of said polymers can be used as binders. The term "poly(meth)acrylate" refers not only to polyacrylates, but also to polymethacrylates and also to polymers comprising both methacrylates and / or methacrylic acid and / or acrylates and / or acrylic acid.

[0157] Preferred polyurethanes are described, for example, in German patent application DE 19948 004 A1, page 4, line 19 to page 11, line 29 (polyurethane prepolymer B1), European patent application EP 0 228 003 A1, page 3, line 24 to page 5, line 40, European patent application EP 0 634 431 A1, page 3, line 38 to page 8, line 9, and International patent application WO 92 / 15405, page 2, line 35 to page 10, line 32.

[0158] Preferred polyesters are described, for example, in DE 4009858 A1, column 6, line 53 to column 7, line 61 and column 10, line 24 to column 13, line 3 and example D, or in WO 2014 / 033135 A2, page 2, line 24 to page 7, line 10 and page 28, line 13 to page 29, line 13. Similarly, the polyesters may have a dendritic structure, as described, for example, in WO 2008 / 148555 A1.

[0159] Preferred polyurethane-poly(meth)acrylate copolymers (e.g. (meth)acrylated polyurethanes) and their preparation are described, for example, in WO 91 / 15528 A1, page 3, line 21 to page 20, line 33, and DE 4437535 A1, page 2, line 27 to page 6, line 22.

[0160] Preferred poly(meth)acrylates are those that can be prepared by multi-stage free radical emulsion polymerization of olefinically unsaturated monomers in water and / or organic solvents. For example, seed-core-shell polymers (SCS polymers) are particularly preferred. Such polymers or aqueous dispersions containing such polymers are known, for example, from WO2016 / 116299A1.

[0161] Preferred polyurethane-polyurea copolymers are polyurethane-polyurea particles, preferably with an average particle size of 40 to 2000 nm, each polyurethane-polyurea particle in reacted form containing at least one isocyanate group-containing polyurethane prepolymer containing anionic groups and / or groups that can be converted into anionic groups, and at least one polyamine containing two primary amino groups and one or two secondary amino groups. Preferably, such copolymers are used in the form of an aqueous dispersion. Such polymers can in principle be prepared, for example, by conventional polyaddition of polyisocyanates with polyols and polyamines.

[0162] In order to crosslink the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the invention, at least one further binder is included in the coating composition comprising the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the invention. Suitable crosslinking binders are amino resins, such as urea-formaldehyde resins or melamine-formaldehyde resins, or isocyanate-terminated polyurethanes with free or blocked isocyanate groups, or isocyanates that can be free or blocked isocyanates. Blocked isocyanates refer to the reaction products of isocyanates in which the isocyanate functional groups have reacted with a "blocking agent". Blocking of isocyanates occurs by reaction of isocyanates with compounds containing active hydrogen. Suitable blocking agents are derivatives of oximes, lactams, phenols, active methylenes, pyrazoles, mercaptans, imidazoles, amines, imines, triazoles, hydroxylamines, and aliphatic or cycloaliphatic alkyl monoalcohols. The blocked isocyanate component does not react at room temperature. The crosslinking reaction between the blocked isocyanate and the hydroxy-functional compound is accomplished at elevated temperatures.

[0163] Additives are binders, which are typically used in minimal amounts to impart special properties to the coating composition.

[0164] Coating Additives (A2) The coating composition may comprise at least one additive selected from the group consisting of reactive diluents, light stabilizers, antioxidants, antifoaming agents, emulsifiers, surfactants, slip additives, polymerization inhibitors, free radical polymerization initiators, catalysts, adhesion promoters, film-forming aids, wetting agents, dispersants, leveling agents, rheology control agents, sag control agents (SCAs), flame retardants, corrosion inhibitors, drying agents, biocides, matting agents, and dyes (colorants and soluble in the coating composition). Further examples of suitable coating additives are described, for example, in the textbook "Lackadditive" ("Additives for Coatings" by Johan Bieleman, Wiley-VCH, Weinheim, 1998). The additives can be used in known and conventional amounts.

[0165] Preferred coating additives are rheology control agents, wetting agents or leveling agents.

[0166] Pigments and fillers (A3) The coating composition according to the present invention may contain pigments, especially when the coating composition is a base coat composition or a filler composition. The terms "color pigment" and "color pigment" are interchangeable and include colored pigments, black pigments and white pigments. As color pigments, inorganic pigments and organic pigments can be used.

[0167] Examples of white pigments include titanium dioxide, zinc white, zinc sulfide, and lithopone. Examples of black pigments include carbon black, iron manganese black, and spinel black. Examples of other color pigments include chromium oxide, chromium oxide hydrate green, cobalt green, ultramarine green, cobalt blue, ultramarine blue, manganese blue, ultramarine violet, cobalt and manganese violet, iron oxide red, cadmium sulfoselenide, molybdate red and ultramarine red, iron oxide brown, mixed brown, spinel and corundum phases, and chrome orange, iron oxide yellow, nickel titanium yellow, chrome titanium yellow, cadmium sulfide, cadmium zinc sulfide, chrome yellow, and bismuth vanadate.

[0168] Possible organic pigments are azo pigments, polycyclic pigments and anthraquinone pigments.

[0169] The term "filler" is known to those skilled in the art, for example from DIN 55943 (date: October 2001). Examples of suitable fillers are kaolin, dolomite, calcite, chalk, calcium sulfate, barium sulfate, talc, silica, especially pyrogenic silica, hydroxides such as aluminum hydroxide or magnesium hydroxide. See further "Fillers" in Roempp Lexikon Lacke und Druckfarben, Georg Thieme Verlag, 1998, p. 250 ff.

[0170] Solvent (A4) In particular, the coating composition may include a solvent. The solvent may be water or an organic solvent. Preferably, water is used as the solvent. Suitable examples of organic solvents include heterocyclic, aliphatic or aromatic hydrocarbons, monofunctional or polyfunctional alcohols, ethers, esters, ketones and amides, such as N-methylpyrrolidone, N-ethylpyrrolidone, dimethylformamide, toluene, xylene, butanol, ethyl glycol and butyl glycol and their acetates, butyl diglycol, diethylene glycol dimethyl ether, cyclohexanone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), acetone, isophorone, or mixtures thereof. Organic solvents can be used in combination and in combination with water in the aqueous coating composition.

[0171] The content of the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention in the entire coating composition is preferably 2% by mass to 30% by mass, more preferably 5% by mass to 25% by mass, and most preferably 7% by mass to 20% by mass.

[0172] Coating layers formed from coating compositions comprising polyester-polyurethane-poly(meth)acrylic hybrid dispersions according to the present invention, and substrates so coated The coating composition for forming the coating layer is applied to the substrate by conventional painting methods well known to those skilled in the art. The substrate material is selected from the group consisting of metal, polymer, wood, glass, mineral-based materials, and composites of any of the aforementioned materials. Untreated or pretreated substrates can be used, the pretreatment usually depending on the chemical nature of the substrate.

[0173] Coating compositions comprising the polyester-polyurethane-poly(meth)acrylate hybrid dispersions according to the present invention are preferably applied by spraying, pneumatically and / or electrostatically. The coating compositions are thermosetting at elevated temperatures, preferably between 60° C. and 180° C., most preferably between 80° C. and 160° C., depending on the reactivity and duration of the crosslinking agent.

[0174] The present invention further provides a substrate coated with a coating layer formed from a coating composition comprising a polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention.

[0175] Multi-layer coatings and multi-layer coated substrates Another object of the present invention is to provide a method for producing a multi-layer coating comprising the following steps: a) applying one or more basecoat compositions to form one or more basecoat layers on a substrate, at least one basecoat composition comprising a polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention; b) applying a clearcoat composition over the one or more basecoat layers to form a clearcoat layer; c) curing one or more basecoat and clearcoat layers simultaneously, or curing one or more layers obtained in steps (a) and (b) separately before applying a subsequent coating layer, or curing all layers obtained in steps (a) and (b) separately. The method includes:

[0176] The multi-layer coated substrate can be a pretreated substrate or an untreated substrate, which can be uncoated or precoated. The individual coating layers are applied by conventional painting methods well known to those skilled in the art. The coating compositions are preferably applied by spraying, pneumatically and / or electrostatically, and at least one coating composition comprises the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention and can be a base coat composition or a filler coating composition.

[0177] The application of the basecoat composition onto the substrate to form the basecoat layer and the application of the clearcoat composition over the basecoat layer(s) is preferably performed by wet-on-wet application, i.e., application where the preceding layer is not cured or not fully cured before applying the next coating composition. Thus, prior to application of the clearcoat composition, the basecoat composition may be flashed off at room temperature (25° C.) and / or alternatively, dried at an elevated temperature.

[0178] The coating composition is thermosetting at elevated temperatures, preferably between 60° C. and 180° C., depending on the reactivity of the crosslinker and the duration, most preferably between 80° C. and 160° C. The coating composition is preferably cured for 15 to 50 minutes, most preferably 20 to 40 minutes.

[0179] Further provided by the present invention is a substrate coated with the multi-layer coating of the present invention. The substrate is selected from the group consisting of metal, polymer, wood, glass, mineral-based materials, and composites of any of the aforementioned materials. Untreated or pretreated substrates can be used, the pretreatment usually depending on the chemical nature of the substrate. Pretreatment of metal substrates is, for example, a zinc phosphating process.

[0180] The multi-layer coatings of the present invention, including the coating compositions according to the present invention, showed excellent appearance in terms of low long wavelength values, which was achieved using polyester-polyurethane-poly(meth)acrylic hybrid dispersions with high solids content, which was surprising since dispersions with such high solids content usually result in coagulation. Furthermore, good compatibility of the basecoat compositions is achieved when at least one of the basecoat compositions comprises the polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to the present invention. EXAMPLES

[0181] method solids content Unless otherwise stated, the solids content was determined according to DIN EN ISO 3251 at 130° C. for 60 min using a 1.0 g weighing portion.

[0182] Isocyanate Content The isocyanate content (NCO content) was determined by adding an excess of a 2% solution of N,N-dibutylamine in xylene to a homogeneous solution of the sample in acetone / N-ethylpyrrolidone (1:1 vol.%) and potentiometric back titration of the excess amine with 0.1 N hydrochloric acid according to DIN EN ISO 3251, DIN EN ISO 11909 and DIN EN ISO 14886. The polymer content (solids content) in the solution is used to refer to the NCO content of the polymer relative to the solids content.

[0183] Hydroxyl Number The hydroxyl number was determined with acetic anhydride in tetrahydrofuran (THF) / dimethylformamide (DMF) solution at room temperature in the presence of 4-dimethylaminopyridine as catalyst according to R.-P. Krueger, R. Gnauck and R. Algeier (Plaste und Kautschuk, 20, 274 (1982)). The excess acetic anhydride remaining after acetylation was completely hydrolyzed and the acetic acid was titrated potentiometrically with alcoholic potassium hydroxide solution.

[0184] Acid value The acid number was determined according to DIN EN ISO 2114 with ethanolic potassium hydroxide solution in a homogeneous solution of tetrahydrofuran (THF) / water (9 parts by volume of THF and 1 part by volume of distilled water).

[0185] Number average molecular weight and weight average molecular weight Number average molecular weight (M n ) and mass average molecular weight (M w ) was determined by gel permeation chromatography using poly(meth)acrylate standards and a tetrahydrofuran / acetic acid mixture (1 mole of acetic acid per liter of tetrahydrofuran).

[0186] Average particle size In this application, the average particle size (z-average) of the particles of the polyester-polyurethane-poly(meth)acrylic hybrid dispersions was measured by measuring the hydrodynamic volume / hydrodynamic radius of the dispersion particles using Photon Correlation Spectroscopy (PCS).

[0187] The measurements were performed using a "Malvern Nano S90" (Malvern Instruments) at 25 ± 1 °C. The instrument covered a size range of 3 nm to 3000 nm and was equipped with a 4 mW He-Ne laser at 633 nm. The polyester-polyurethane-poly(meth)acrylic hybrid dispersions were diluted with particle-free deionized water as the dispersion medium and the polymer hybrid dispersions in 1 ml polystyrene cuvettes were measured at the appropriate scattering intensity. The measurements were performed five times and repeated with a second freshly prepared sample. The reported mean particle size (z-average) is the arithmetic mean of the mean particle size (intensity weighted) of the individual preparations. Polystyrene standards with certified particle sizes between 50 and 3000 nm were used for validation.

[0188] viscosity The viscosity of the polyester-polyurethane during synthesis was measured at 1250 s at a temperature of 140 °C using a CAP2000H viscometer equipped with spindle 03. -1 ~2500s -1The measurements were carried out in accordance with DIN EN ISO 2884-1 using a shear rate of 100 MPa.

[0189] The viscosity of the final polyester-polyurethane dispersion and the final polyester-polyurethane-poly(meth)acrylic hybrid dispersion was measured at a temperature of 23 °C using a Rheolab QC rotational rheometer equipped with a cc27 cylinder at 1000 s -1 The shear rate was measured according to DIN 53019-1.

[0190] Glass transition temperature The glass transition temperature was determined according to DIN-EN-ISO11357-1 and -2. The liquid dispersion was applied by drawdown (50 μm) onto a glass substrate and dried at 130° C. for 60 min. Nitrogen gas was used to obtain the desired atmosphere. The dried sample was placed in a crucible. When the starting temperature reached −90° C., the temperature was increased at 10 K / min to the selected limit and cooled at the same rate to the selected limit (−90° C. to 100° C.). A second measurement was then performed at the same temperature limit and the glass transition temperature was measured during the heating step of the second measurement.

[0191] Appearance evaluation The appearance of the coated substrates was evaluated using a Byk / Gardner Wavescan measuring instrument. A laser beam was irradiated at an angle of 60° onto the surface of the substrate coated with the multilayer coating, and the reflected light in the short wavelength range (0.3-1.2 mm) and long wavelength range (1.2-12 mm) was measured. The smaller the short wavelength (LW) and long wavelength (LW) values, the better the appearance. In addition, a wavescan measuring device was used to measure the clarity of the image reflected from the surface of the multilayer structure. This parameter is called "distinctness of image" (DOI), and the higher the value, the better the appearance.

[0192] All amounts listed are in parts or grams by weight and percentages are percent by weight unless otherwise specified.

[0193] Comparative Example: Synthesis of Polyester-Polyurethane-Poly(meth)acrylic Hybrid Dispersions C1 to C3 The preparation of carboxyl-rich polyurethanes and polyesters was carried out according to Example 3 of US 10,233,353 B2 (COOH-rich polyurethane: 23.3 g dimethylolpropionic acid, 53.4 g H 12 MDI, 23.3 g 12-hydroxystearic acid; acid value 141 mg KOH / g) and according to Example 4 (polyester: 375 g 1,6-hexanediol, 118 g trimethylolpropane, 389 g isophthalic acid, 118 g adipic acid; acid value 10 mg KOH / g). The synthesis of polyester-polyurethane dispersions was carried out analogously to Example 5 of US 10,233,353 B2 on the basis of comparative polyester-polyurethane-poly(meth)acrylic hybrid dispersions C1 and C3. Comparative dispersion C1 reproduces Example 6 of said patent. The amounts in Table 1 are given in grams.

[0194] [Table 1]

[0195] As shown in Table 1, polymerization at a solids content of 42 wt % caused coagulation and no polyester-polyurethane-poly(meth)acrylic hybrid dispersion was obtained.

[0196] Synthesis of the Polyester-Polyurethane-Poly(meth)acrylic Hybrid Dispersion of the Present Invention Synthesis of polyesters PE1 and PE2 The compounds in Table 2 were mixed in a reactor equipped with a stirrer and a Dean-Stark apparatus. The temperature was raised to 220 °C and carefully controlled to reduce monomer losses. Reaction monitoring was performed by titration. Polyester PE2 with the indicated properties was obtained. The condensation process of PE1 was carried out until the acid number reached less than 10 mg KOH / g. After cooling, polyester PE1 was adjusted with methyl ethyl ketone (MEK) to obtain a solids content of 74 wt.%.

[0197] [Table 2]

[0198] Synthesis of Polyurethanes PU1 to PU7 A N2 gas separator equipped with a stirrer and a reflux condenser 2 The compounds in Table 3 were reacted in a purged reactor to give polyurethanes PU1 to PU7 having the properties shown.

[0199] Dimethylolpropionic acid (DMPA), isophorone diisocyanate (IPDI) and methyl ethyl ketone (MEK) were mixed for the synthesis of PU1, and the temperature was carefully raised to 77°C. The reaction was monitored by titration. After the theoretical NCO content reached 14.9%, it was cooled and ethylene glycol was added. The temperature was kept at 77°C until complete conversion of NCO groups was detected by titration. Then trimellitic anhydride was added to stop the reaction at a certain acid value.

[0200] Dimethylolpropionic acid, methyl ethyl ketone, ethylene glycol and 4,4'-methylenebis(cyclohexyl isocyanate) were mixed for the synthesis of PU2, and the temperature after the exothermic reaction was kept at 77°C. The reaction was monitored by titration. After reaching complete conversion of NCO groups, MEK was added to adjust the solid content to 60% by weight. Then, trimellitic anhydride was added to stop the reaction at a certain acid value.

[0201] PU1 and PU2 were diluted with MEK to a solid content of about 70% by weight. PU3, PU4 and PU7 were synthesized similarly to PU1. Following the preparation of PU2, PU5 and PU6 were obtained and diluted to a solid content of 55% or 57%, respectively.

[0202] [Table 3]

[0203] Synthesis of polyester-polyurethane dispersions PEUD1, PEUD2, PEUD4 and polyester-polyurethane PEU3 Synthesis of polyester-polyurethane dispersion PEUD1 To prepare polyester-polyurethane dispersion 1, 7814.0 g of PE1 and 2218.0 g of PU2 were mixed in a reactor equipped with a stirrer. The temperature was carefully increased up to 160° C. while applying a vacuum (20 mbar). The process was monitored by titration and viscosity measurement at 140° C. An acid number of 29 mg KOH / g and a viscosity of about 1800 mPa*s (CAP2000H, spindle 03, 140° C., shear rate 1250 s -1 After reaching 100° C., the temperature was reduced to 115° C. and 160 g of dimethylethanolamine was added over 10 min. Water was added at 90° C. to adjust the solids content of PEUD1 to 55% by weight. Further properties are shown in Table 4.

[0204] Synthesis of polyester-polyurethane dispersion PEUD2 To prepare polyester-polyurethane dispersion 2, 1084.0 g of PE2 and 415.8 g of PU2 were mixed in a reactor equipped with a stirrer. The temperature was carefully increased up to 140°C while applying a vacuum (40-60 mbar). The process was monitored by titration and viscosity measurement at 140°C. An acid number of 32 mg KOH / g and a viscosity of about 1400 mPa*s (CAP2000H, spindle 03, 140°C, shear rate 2500 s) were obtained. -1 After reaching 100° C., the temperature was lowered to 80° C., and 46.0 g of dimethylethanolamine was added over 10 minutes. Water was added at 80° C. to adjust the solid content of PEUD2 to 45% by mass.

[0205] The characteristics of PEUD1 and PEUD2 are shown in Table 4.

[0206] [Table 4]

[0207] 1 The viscosity was measured using a Rheolab QC rotational rheometer equipped with a cc27 cylinder at a temperature of 23 °C for 1000 s -1 The measurements were performed using a shear rate of 0.05 mm.

[0208] Synthesis of polyester polyurethane PEU3 To prepare polyester-polyurethane 3, 2441.8 g of PE1 and 693.1 g of PU2 were mixed in a reactor equipped with a stirrer. The temperature was carefully increased up to 140°C while applying a vacuum (50-120 mbar). The process was monitored by titration and viscosity measurement at 140°C. An acid number of 26 mg KOH / g and a viscosity of about 2000 mPa*s (CAP2000H, spindle 03, 140°C, shear rate 1250 s) were obtained. -1 After reaching 82° C., the temperature was lowered to 82° C., and 203.0 g of n-butyl acrylate was added. Polyester-Polyurethane 3 having a solid content of about 90% by weight was obtained.

[0209] Synthesis of polyester-polyurethane dispersion PEUD4 To prepare polyester-polyurethane dispersion 4, 2168.3 g of PE1 and 831.7 g of PU2 were mixed in a reactor equipped with a stirrer. The temperature was carefully increased up to 140°C while applying a vacuum (50-120 mbar). The process was monitored by titration and viscosity measurement at 140°C. An acid number of 28 mg KOH / g and a viscosity of about 1800 mPa*s (CAP2000H, spindle 03, 140°C, shear rate 1250 s) were obtained. -1 After reaching a temperature of 100° C., the temperature was lowered to 100° C. and 187.3 g of butyl diglycol was added. 60.0 g of dimethylethanolamine was added over 10 minutes. Then, 1925.0 g of water was slowly added at 95° C. Polyester-polyurethane dispersion 4 with a solid content of 48.2% by weight was obtained.

[0210] Synthesis of polyester-polyurethane-poly(meth)acrylic hybrid dispersions B1-B17 of the present invention by emulsion polymerization Examples B1 to B11 The synthesis was carried out in a 3.5 L steel reactor with an anchor stirrer for B1-B11. The stirrer was at a low setting (50-100 rpm). For examples B9 and B10, a glass reactor with a 150 rpm stirrer was used. The reactor used thermal oil for temperature control. Undiluted PEUD1 was used for the synthesis of B1-B3, B5, B7 and B10, and undiluted PEUD2 was used for the synthesis of B9. For the synthesis of B4 and B6, PEUD1 was diluted with 569 g of deionized water. For the synthesis of B8, PEUD1 was neutralized with 17.2 g of dimethylethanolamine (DMEA) and diluted with 26.9 g of butyl diglycol and 792.2 g of deionized water to obtain a dispersion with a solids content of 40% by weight and a degree of neutralization of about 70%. Undiluted or diluted PEUD1 or PEUD2 were heated to 80°C. The amounts in Table 5 are given in grams.

[0211] In Examples B1 to B7, the (meth)acrylic monomer or monomers were mixed with 2 g of tert-butyl-peroxy-2-ethylhexanol. Each mixture was added slowly over 3 hours at 80° C. Then, 0.4 g of tert-butyl-peroxy-2-ethylhexanol was added and stirred at 80° C. for another 2 hours.

[0212] In Example B8, the (meth)acrylic monomer and 2.4 g of tert-butyl-peroxy-2-ethylhexanol were added slowly over 2.5 hours at 80° C. Then, 0.4 g of tert-butyl-peroxy-2-ethylhexanol was added and stirred at 80° C. for another 2 hours.

[0213] In Example B9, the (meth)acrylic monomer was mixed with 0.3 g of tert-butyl-peroxy-2-ethylhexanol. Each mixture was added slowly over 3 hours at 80° C. Then, the mixture was stirred at 80° C. for an additional 2 hours.

[0214] In Example B10, the (meth)acrylic monomer was mixed with 0.2 g of tert-butyl-peroxy-2-ethylhexanol. Each mixture was added slowly over 3 hours at 80° C., followed by stirring for 1 hour at 80° C. Then, 0.1 g of tert-butyl-peroxy-2-ethylhexanol was added and stirred for another hour at 80° C.

[0215] For the synthesis of B11, PEUD1 was diluted with 79.9 g of butyl diglycol and 257.8 g of deionized water. Then (meth)acrylic monomer and 1.3 g of tert-butylperoxy-2-ethylhexanol were added slowly over 3 hours at 80° C. After that, the dispersion was stirred at 80° C. for another 2 hours.

[0216] After the reaction and during the cooling period, dispersions B1 to B3, B5 and B10 were diluted with 230 g (B1, B2), 105 g (B3, B5) or 21 g (B10) of deionized water. Dispersions B4, B6 to B9 and B11 were not further diluted.

[0217] [Table 5]

[0218] Table 6 shows the properties of Dispersions B1 to B11.

[0219] [Table 6]

[0220] Examples B12 to B14 The same equipment was used for the synthesis of dispersions B12-B14 as in examples B1-B6 and B8. The stirring speed was set at 150 rpm. According to table 7, 509.7 g of polyester-polyurethane 3 was diluted with 62.9 g of (meth)acrylate, after which 13.5 g of dimethylethanolamine was added. Over a period of 15 minutes, 463.4 g of water was added at 80° C., resulting in a monomer-swollen polyester-polyurethane dispersion with a theoretical solids content of about 43.7% by weight. Then, 0.6 g of tert-butylperoxy-2-ethylhexanol was added over a period of 2 hours, and the temperature was held at 80° C. for 2 hours. An additional 0.3 g of tert-butyl-peroxy-2-ethylhexanol was added, and stirring was continued for 1 hour.

[0221] Example B15 The same equipment as in Examples B1-B6 and B8 was used for the synthesis of Dispersion B15. The stirring speed was set at 150 rpm. At 110°C, 1456.0 g of Polyester-Polyurethane 3 was diluted with 316.0 g of t-butyl acrylate, 197.5 g of styrene and 323.9 g of n-butyl acrylate. The temperature was reduced to 95°C and 220.0 g of butyl diglycol was added followed by 63.2 g of dimethylethanolamine. After 10 minutes, 3100.0 g of water was added at 80°C, resulting in a monomer-swollen polyester-polyurethane dispersion with a theoretical solids content of about 23.1% by weight. 2500.0 g of this monomer swollen polyester-polyurethane dispersion was heated to 80° C. and 8.2 g of tert-butyl-peroxy-2-ethylhexanol was added over 2.5 hours and the reaction temperature was maintained at 80° C. for an additional 2 hours. 2.0 g of tert-butyl-peroxy-2-ethylhexanol was added and stirring was continued for 1 hour.

[0222] Examples B16 and B17 For the synthesis of dispersions B16 and B17, the same equipment was used as in examples B1-B6 and B8. The stirring speed was set at 150 rpm. According to table 7, 1065.1 g of PEUD4 was diluted with 185.7 g of water and heated to 80 ° C. 127.3 g of n-butyl acrylate, 73.5 g of t-butyl acrylate and 46.0 g of styrene were added over 3 hours. In parallel with the monomer addition, 2.4 g of tert-butyl-peroxy-2-ethylhexanol (B16) or a mixture of 52.5 g of water and 4.8 g of ammonium peroxydisulfate (B17) was added to the reactor. For the synthesis of dispersion B16, 1.0 g of tert-butyl-peroxy-2-ethylhexanol was used, the reaction temperature was kept at 80 ° C and the reaction was continued for another 2 hours.

[0223] [Table 7]

[0224] Table 8 shows the acid values ​​of dispersions B12 to B17.

[0225] [Table 8]

[0226] As is evident from Tables 5 and 7, the polyester-polyurethane-poly(meth)acrylic hybrid dispersions of the present invention exhibited solid contents much greater than 40% by weight, and no coagulation was observed. This was surprising, since in the comparative polyester-polyurethane-poly(meth)acrylic hybrid dispersion C3, coagulation occurred already at a solid content of 42% by weight, whereas the polyester-polyurethane-poly(meth)acrylic hybrid dispersion did not coagulate even at a solid content as high as about 60% by weight (B3).

[0227] Preparation of basecoat compositions containing the polyester-polyurethane-poly(meth)acrylic hybrid dispersions B1-B6 and B11 of the present invention Preparation of milling base MB1 A milling base was prepared from 19.1 parts by weight of deionized water, 0.9 parts by weight of a 10% dimethylethanolamine solution, 8.3 parts by weight of a water-based polyester having a solids content of 60.0±1.0% by weight (measured at 130° C. for 1 hour) and an acid number of 29-34 mg KOH / g solids, 15 parts by weight of titanium dioxide, 0.5 parts by weight of 2-ethylhexanol, 34.4 parts by weight of barium sulfate, 1.8 parts by weight of additives, 2.6 parts by weight of carbon black, and 17.4 parts by weight of a polyurethane dispersion having a solids content of 33.0±1.0% by weight (measured at 130° C. for 1 hour) and an acid number of 19-23 mg KOH / g solids.

[0228] Preparation of the Basecoat Composition Basecoat compositions were prepared by mixing the ingredients in Table 9. Inventive basecoat compositions BC-I1 to BC-I7 contained inventive polyester-polyurethane-poly(meth)acrylic hybrid dispersions B1 to B6 and B11, while comparative basecoat compositions BC-C1, BC-C2 and BC-C3 contained comparative aliphatic polycarbonate ester polyether polyurethane dispersion (Impranil® DLU) (BC-C1), polyurethane dispersion PEUD-1 (BC-C2), which is an intermediate product with no ethylenically unsaturated monomer added and polymerized, or comparative polyester-polyurethane-poly(meth)acrylic hybrid dispersion C2 (see Table 1) (BC-C3) prepared similarly to Example 5 of US 10,233,353 B2. Typical polyurethane, polyester and polyacrylate dispersions were used as the main resin for all basecoat compositions. As the basecoat compositions were one-part compositions, a melamine-formaldehyde crosslinker was used as a typical crosslinker for such compositions. The inventive or comparative basecoat compositions were adjusted with water to give basecoat compositions with a solids content of 27.5%.

[0229] [Table 9]

[0230] 1Polyurethane dispersion: solids content: 32-34%; acid number: 19-23 mg KOH / g solids, hydroxyl number: 17 mg KOH / g solids. A polyurethane dispersion is known from WO2016000947A1. 2 Aqueous polyester solutions: solids content: 60±1.0% (measured for 1 h at 130° C.); acid number: 29-34 mg KOH / g solids. Aqueous polyester solutions are known from DE 4009858, example D. 3 Polyacrylate dispersion: solids content: 25.5-27.5%, acid number: 16.6-17.6 mg KOH / g solids, hydroxyl number 16.5-17.5 mg KOH / g solids. Polyacrylate dispersions are known from WO2017148796A1. 4 Applicable viscosity: 85±25mPa*s (RheolabQC, cc27, shear rate 1000s -1 (Use Preparation of Basecoat Composition 2 (BC2) The BC2 formulation was prepared by mixing 26.5 parts by weight of deionized water, 3.1 parts by weight of a 10% dimethylethanolamine solution, 4.5 parts by weight of a water-based polyester having a solids content of 60.0±1.0% by weight (measured at 130°C for 1 hour) and an acid number of 29-34 mg KOH / g solids, 6.8 parts by weight of a rheology agent, 2.0 parts by weight of 2-ethylhexanol, 9.2 parts by weight of butoxypropanol, 1.0 part by weight of dipropylene glycol methyl ether, 4.1 parts by weight of additives, 14.0 parts by weight of carbon black, 7.5 parts by weight of melamine resin, a solids content of 35.5±1.0% by weight, A first polyurethane polyacrylate dispersion having a solids content of 36.0±1.0% by weight (measured at 130° C. for 1 hour) and an acid number of 32-35 mg KOH / g solids, a second polyurethane polyacrylate dispersion having a solids content of 36.0±1.0% by weight (measured at 130° C. for 1 hour), a third polyurethane polyacrylate dispersion having a solids content of 44.0±1.0% by weight (measured at 130° C. for 1 hour) and an acid number of 30-32 mg KOH / g solids, and 3.0 parts by weight of an OH-functional aqueous polyacrylate having a solids content of 46.5±1.0% by weight (measured at 130° C. for 1 hour).

[0231] Application of the coating composition The spray booth was kept at 25 °C and humidity 70%. The basecoats BC-C1 - BC-C3 and BC-I1 - BC-I7 were applied by electrostatic spray application (ESTA) on panels with an electronic dip coating (Cathoguard, BASF Coatings GmbH) in a layer thickness of about 25 μm. After a flash-off time of 3.5 min at 80 °C, the basecoat BC2 was applied in a layer thickness of about 12 μm (BC-C1, BC-C2 and BC-I1 - BC-I6) or in a layer thickness of about 24 μm (BC-C3 and BC-I7). After a flash-off time of 3.5 min at 80 °C, the clearcoat (UniGloss, BASF Coatings GmbH) was applied in a layer thickness of about 40 μm. The coatings were then cured for 30 min at 140 °C.

[0232] Coating Layer Testing The obtained multilayer coatings were evaluated for appearance in terms of long wavelength (LW) and short wavelength (SW) and for gloss in terms of DOI (distinctness of image) by means of an orange peel meter (BYK 4840 wave scan dual, BYK-Gardner GmbH) according to DIN EN ISO 2813.

[0233] [Table 10]

[0234] The multilayer coatings containing polyester-polyurethane-poly(meth)acrylic hybrid dispersions as basecoat 1 show an excellent appearance in terms of small long wavelength values, since this value is lower compared to the multilayer coatings containing basecoat 1 of the prior art containing an aliphatic polycarbonate ester polyether polyurethane dispersion (Impranil® DLU). Comparison with the multilayer coatings containing PEUD-1 as basecoat 1, which is also present in the inventive dispersions B1 to B7, demonstrates that the further emulsion polymerization with acrylate monomers improves the appearance of the multilayer coatings. It was surprising that the emulsion polymerization of polyester-polyurethane as described above with ethylenically unsaturated monomers improves the appearance in terms of small long wavelength values. Moreover, the multilayer coatings containing polyester-polyurethane-poly(meth)acrylic hybrid dispersions as basecoat 1 show an excellent appearance in terms of small long wavelength values ​​in combination with small short wavelength values ​​and high DOI values.

[0235] Furthermore, the compatibility of the basecoat composition containing the polyester-polyurethane-poly(meth)acrylic hybrid dispersion of the present invention with the second basecoat composition was improved compared to the comparative basecoat composition.

Claims

1. A polyester-polyurethane-poly(meth)acrylic hybrid dispersion comprising the steps of: a. at least one carboxyl group-containing polyurethane having an acid value of more than 200 mg KOH / g to 400 mg KOH / g and at least one terminal carboxyl group; and at least one hydroxyl-containing polyester having a hydroxyl value of 50 mg KOH / g to 300 mg KOH / g. Obtaining polyester-polyurethane, followed by b. A step of polymerizing ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, by radical polymerization in the presence of the polyester-polyurethane of step (a). can be obtained by one or more solvents are present and / or used during steps (a) and / or (b) and / or are added after step (b); Polyester-polyurethane-poly(meth)acrylic hybrid dispersion.

2. 2. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1, characterized in that said at least one polyurethane in step (a) has at least two carboxyl groups at each of both ends and / or said at least one polyurethane and at least one polyester in step (a) are esterified in the presence of one or more solvents to obtain a polyester-polyurethane dispersion.

3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, characterized in that the polyester-polyurethane obtained in step (a) has an acid value in the range of 10 to 50 mg KOH / g solids.

4. 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, characterized in that the polyester-polyurethane dispersion obtained in step (a) has a solids content of ≧40% by weight and / or is aqueous.

5. 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, characterized in that the ethylenically unsaturated monomer in step (b) is added to the polyester-polyurethane in step (a) before the addition of a radical initiator or simultaneously with the radical initiator.

6. 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, characterized in that the radical polymerization of the ethylenically unsaturated monomers in step (b) is initiated by a water-soluble initiator or a water-insoluble initiator.

7. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, characterized in that the (meth)acrylic monomer in step (b) comprises an alkyl (meth)acrylate monomer.

8. 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, characterized in that the polyester-polyurethane-poly(meth)acrylic hybrid has a glass transition temperature of -50°C to +50°C.

9. 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, characterized in that the solids content of the polyester-polyurethane-poly(meth)acrylic hybrid dispersion is ≧40% by weight.

10. 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, wherein the polyester-polyurethane-poly(meth)acrylic hybrid dispersion comprises 45 to 90% by weight of polyester-polyurethane and 10 to 55% by weight of poly(meth)acrylate, these weight percentages being based on the solid content of the polyester-polyurethane-poly(meth)acrylic hybrid.

11. 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion of claim 1 or 2, wherein said polyester-polyurethane of step (a) is physically mixed with said poly(meth)acrylate of step (b) and / or covalently bonded with said poly(meth)acrylate of step (b).

12. The polyester-polyurethane-poly(meth)acrylic hybrid prepared with one or more monoethylenically unsaturated monomers has a number average molecular weight (M ｎ ) and / or a weight average molecular weight (M ｗ 3. The polyester-polyurethane-poly(meth)acrylic hybrid dispersion according to claim 1 or 2, wherein

13. A method for producing a polyester-polyurethane-poly(meth)acrylic hybrid dispersion as defined in claim 1, comprising the steps of: (a) at least one carboxyl group-containing polyurethane having an acid value of greater than 200 mg KOH / g to 400 mg KOH / g and at least one terminal carboxyl group; and at least one hydroxyl-containing polyester having a hydroxyl value of 50 mg KOH / g to 300 mg KOH / g. Obtaining polyester-polyurethane, followed by (b) polymerizing ethylenically unsaturated monomers, including at least a (meth)acrylic monomer, by radical polymerization in the presence of the polyester-polyurethane of step (a). Including, one or more solvents are present and / or used during steps (a) and / or (b) and / or added after step (b); Thus, the polyester-polyurethane-poly(meth)acrylic hybrid dispersion is obtained.

14. A coating composition comprising a polyester-polyurethane-poly(meth)acrylic hybrid dispersion as defined in claim 1 or 2.

15. A coating layer formed from the coating composition of claim 14.

16. A substrate coated with the coating layer of claim 15.

17. 15. Use of the coating composition of claim 14 in automotive coatings.

18. A method for producing a multi-layer coating comprising the steps of: a. applying one or more basecoat compositions to form one or more basecoat layers on a substrate, at least one of the basecoat compositions comprising a polyester-polyurethane-poly(meth)acrylic hybrid dispersion as defined in claim 1 or 2; b. applying a clearcoat composition over the one or more basecoat layers to form a clearcoat layer; c) curing the one or more basecoat layers and the clearcoat layer simultaneously, or curing one or more layers obtained in steps a. and b. separately before applying a subsequent coating layer, or curing all layers obtained in steps a. and b. separately. The method includes:

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