EP1794206A1

EP1794206A1 - Hydrolysis-stable coating agent composition

Info

Publication number: EP1794206A1
Application number: EP05791613A
Authority: EP
Inventors: Thorsten Rische; Gerald Kurek; Jürgen Meixner; Torsten Pohl; Uwe Klippert; Thomas Feller
Original assignee: Bayer MaterialScience AG
Current assignee: Covestro Deutschland AG
Priority date: 2004-09-20
Filing date: 2005-09-08
Publication date: 2007-06-13
Also published as: CN101061153A; WO2006032373A1; JP2008513555A; CA2580744A1; AU2005287668A1; KR20070059160A; BRPI0515486A; RU2007114782A; DE102004045533A1; US20060084775A1; AU2005287668B2; NO20071944L

Abstract

The invention relates to hydrolysis-stable, aqueous coating agent compositions, to a method for the production thereof and to their use as soft feel paint.

Description

Hydrolysis-stable coating composition

The invention relates to hydrolysis-stable, aqueous coating compositions, to a process for their preparation and to use as soft-feel coating.

Polyurethane-polyurea dispersions (PU dispersions) and aqueous formulations of PU dispersions are known in the art. An important field of application of aqueous preparations of ionically modified PU dispersions is in the field of coating plastic parts.

Due to aesthetic and technical requirements, plastic parts are usually painted to protect the plastic from external influences, such as sunlight, chemical, thermal and mechanical stress, to achieve certain hues and color effects, to cover defects of the plastic surface or to the plastic surface a pleasant grip To give (haptic). In order to improve the haptic properties of plastic parts, so-called softfeel lacquers are increasingly being used in recent years. "Softfeel effect" in the sense of the present invention denotes a special feel (feel) of the painted surface; This feel can be described in terms of velvety, soft, rubbery, warm. Following the trend of avoiding emissions of solvents into the environment, aqueous soft-feel coatings based on polyurethane chemistry have become established in recent years, as disclosed by way of example in DE-A 44 06 159. In addition to an excellent softfeel effect, these coatings also give coatings with good resistance and protective effect for the plastic substrate. In the meantime, however, it has been shown that these lacquers and coatings often have inadequate resistance to hydrolysis.

The object of the present invention was therefore to provide coating compositions which, in addition to the o.g. mechanical and haptic properties, compared to coatings of the prior art, lead to significantly more hydrolysis-stable coatings.

As described, for example, in DE-A 44 06 159, plastic coating compositions with the desired haptic soft feel properties consist to a certain extent of PU dispersions which have no appreciable amounts of hydroxy-functional groups.

DE-A 101 22 444 describes hydrolystable, ionically and / or nonionically hydrophilicized polyurethane-polyurea- (PUR) -dispersions based on polycarbonate polyols and polytetra methylene glycol polyols. The dispersions lead to hydrolysis-resistant, kink-resistant and scratch-resistant coatings on a wide variety of substrates in one-component coating compositions. However, an application of these dispersions as softfeel paints is not described. It has now been found that aqueous two-component (2K) coating compositions which contain both non-functional polyurethane polymers based on polycarbonate polyols and polytetramethylene glycol polyols and hydrophilic, hydroxyl group-containing polyurethane polymers exhibit excellent hydrolytic stability and simultaneously the desired haptic properties ,

The present invention therefore relates to aqueous coating compositions containing

I) hydroxyl-free polyurethanes and / or polyurethane ureas based on polycarbonate polyols and polytetramethylene glycol polyols,

IT) ionically modified, hydroxyl and / or amino-containing polyurethanes and / or polyurethane ureas and

(IQ) at least one crosslinker as well

(IV) optionally further film-forming resins.

The non-functional PUR polymers (I) and the hydroxy- and / or amino-functional crosslinkable PUR polymers (H) contain compounds selected from the groups L1) to 1.6) or π.l) to II.6) :,

I.iyil.l) polyisocyanates,

1.2) Mixture of polycarbonate and polytetramethylene glycol polyols having number average molecular weights of 200 to 8000 g / mol,

π.2) polymeric polyols having a number average molecular weight of from 200 to 8000 g / mol,

I.3) / π.3) low molecular weight compounds of molecular weight 62 to 400 which in total have two or more hydroxyl and / or amino groups,

I.4) /π.4) compounds which have a hydroxyl or amino group,

I.5) / π.5) isocyanate-reactive, ionic or potentially ionic hydrophilizing compounds,

I.6) /I1.6) isocyanate-reactive nonionic hydrophilizing compounds.

Suitable polyisocyanates of component 1.1) and Hl) are the aromatic, araliphatic, aliphatic or cycloaliphatic polyisocyanates known to the person skilled in the art having an NCO functionality of preferably> 2, which also comprises iminooxadiazinedione, isocyanurate, Uretdione, urethane, allophanate, biuret, urea, Oxadiazintrion, oxazolidinone, acyl urea and / or carbodiimide structures may have. These can be used individually or in any mixtures with one another.

Examples of suitable polyisocyanates are butylene diisocyanate, hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 2,2,4 and / or 2,4,4-trimethylhexamethylene diisocyanate, the isomeric bis (4,4'-isocyanatocyclohexyl) methanes or their mixtures of any isomers content, isocyanatomethyl-l, 8-octane diisocyanate, 1,4-cyclohexylene diisocyanate, 1,4-phenylene diisocyanate, 2,4- and / or 2,6-toluene diisocyanate, 1,5-naphthylene diisocyanate, 2,4'- or 4 , 4'-diphenylmethanediisocyanate, triphenylmethane-4,4 ', 4 "-triisocyanat or derivatives based on the above-mentioned diisocyanates having uretdione, isocyanurate, urethane, allophanate, biuret, Immooxadiazindion- and / or Oxadiazintrionstruktur with more than 2 NCO groups as described by way of example in J. Prakt. Chem. 336 (1994) p. 185-200.

As an example of a non-modified polyisocyanate having more than 2 NCO groups per molecule, see e.g. 4-Isocyanatomethyl-l, 8-octane diisocyanate (nonane triisocyanate) called.

Preference is given to polyisocyanates or polyisocyanate mixtures of the abovementioned type with exclusively aliphatically and / or cycloaliphatically bonded isocyanate groups.

Particularly preferred are hexamethylene diisocyanate, isophorone diisocyanate, the isomeric bis (4,4'-isocyanatocyclohexyl) methanes and mixtures thereof.

The PUR polymers (I) contain as component 1.2) a mixture of polycarbonate polyols and polytetramethylene glycol polyols. The proportion of polycarbonate in the mixture is between 20 and 80 wt.%, The proportion of polytetramethylene glycol polyols is between 80 and 20 wt.%. Preference is given to a proportion of 30 to 75 wt .-% of polytetramethylene glycol polyols and a content of 25 to 70 wt .-% of polycarbonate polyols. Particular preference is given to a proportion of from 35 to 70% by weight of polytetramethylene glycol polyols and from 30 to 65% by weight of polycarbonate polyols, in each case with the proviso that the sum of the percentages by weight of the polycarbonate and polytetramethylene glycol polyols is 100%.

The polyols mentioned under 1.2) have an OH functionality of at least 1.8 to 4. Preference is given to using polyols in a mean molecular weight range of from 200 to 8000 with an OH functionality of from 2 to 3. Particular preference is given to polyols having average molecular weight ranges from 200 to 3000. Suitable polytetramethylene glycol polyols are polytetramethylene glycol polyethers which can be prepared, for example, by polymerization of tetrahydrofuran by cationic ring opening.

Hydroxyl-containing polycarbonate polyols corresponding to the definition of component 1.2) are obtained by reaction of carbonic acid derivatives, e.g. Diphenyl carbonate, dimethyl carbonate or phosgene with diols available.

As such diols come e.g. Ethylene glycol, 1,2- and 1,3-propanediol, 1,3- and 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,12-dodecanediol, neopentyl glycol, 1,4-bis-hydroxymethylcyclo hexane, 2-methyl-l, 3-propanediol, 2,2,4-trimethylpentanediol-l, 3, dipropylene glycol, polypropylene glycols, dibutylene glycol, polybutylene glycols, bisphenol A, tetrabromobisphenol A but also lactone-modified diols in question. Preferably, the Diolkompomponente contains 40 to 100 wt .-% of hexanediol, preferably 1,6-hexanediol and / or hexanediol derivatives, particularly preferably those derivatives which in addition to terminal OH groups ether or ester groups, such as products obtained by reaction of 1 mole of hexanediol with at least 1 mole, preferably 1 to 2 moles of caprolactone or by etherification of hexanediol with itself to di- or trihexylene glycol were obtained. The preparation of such derivatives is e.g. known from DE-A 15 70 540. The polyether-polycarbonate diols described in DE-A 37 17 060 can also be used.

The hydroxylpolycarbonates are preferably linear, but may optionally be branched by the incorporation of polyfunctional components, in particular low molecular weight polyols. For example, glycerol, trimethylolpropane, hexanetriol-1,2,6, butanetriol-1,2,4, trimethylolpropane, pentaerythritol, quinitol, mannitol and sorbitol or methyl glycoside and 1,3,4,6-dianhydrohexitols are suitable for this purpose.

Polyester polyols which can be used as compounds π.2) preferably have a molecular weight Mn of from 400 to 6000, particularly preferably from 600 to 3000. Their hydroxyl number is generally 22 to 400, preferably 50 to 200 and particularly preferably 80 to 160 mg / KOH / g, and have an OH functionality of 1.5 to 6, preferably from 1.8 to 3 and particularly preferably from 2 on.

Highly suitable examples are the on are the known polycondensates of di- and optionally poly (tri, tetra) ols and di- and optionally poly (tri, tetra) carboxylic acids or hydroxycarboxylic acids or lactones. Instead of the free polycarboxylic acids, it is also possible to use the corresponding polycarboxylic acid anhydrides or corresponding polycarboxylic acid esters of lower alcohols for the preparation of the polyesters. Examples of suitable diols are ethylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyalkylene glycols such as polyethylene glycol, furthermore propanediol, butanediol (1,4), hexanediol (1,6), neopentyl glycol or Hydroxypivalinsäureeneopenthylglykolester, wherein the latter three compounds are vor¬ assigned to. Examples of suitable polyols to be used here are trimethylolpropane, glycerol, erythritol, pentaerythritol, trimethylolbenzene or trishydroxyethyl isocyanurate.

Suitable diGarboxylic acids are, for example, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, cyclohexanedicarboxylic acid, adipic acid, azelaic acid, sebacic acid, glutaric acid, tetrachlorophthalic acid, maleic acid, fumaric acid, itaconic acid, malonic acid, suberic acid, 2-methylsuccinic acid, 3,3- Diethylglutaric acid, 2,2-dimethyl-succinic acid. Anhydrides of these acids are also useful, as far as they exist. As a result, for the purposes of the present invention, the anhydrides are encompassed by the term "acid". Monocarboxylic acids such as benzoic acid and hexanecarboxylic acid can also be used, provided that the average functionality of the polyol is higher than 2. Saturated aliphatic or aromatic acids are preferred, such as adipic acid or isophthalic acid. As polycarboxylic acid which may optionally be used in smaller amounts, trimellitic acid may be mentioned here.

Hydroxycarboxylic acids which can be used as reactants in the preparation of a hydroxyl-terminated polyester polyol include hydroxycaproic acid, hydroxybutyric acid, hydroxydecanoic acid, hydroxystearic acid, and the like. Useful lac- tones are u. a. Caprolactone, butyrolactone and the like.

Compounds of component II.2) may at least partially contain primary or secondary amino groups as NCO-reactive groups.

Suitable compounds H2) are also hydroxyl-containing polycarbonates having a molecular weight Mn of 400 to 6000, preferably 600 to 3000, which are obtainable, for example, by reaction of carbonic acid derivatives, for example diphenyl carbonate, dimethyl carbonate or phosgene with polyols, preferably diols. Examples of such diols are ethylene glycol, 1,2- and 1,3-propanediol, 1,3- and 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, 1,4-bishydroxymethylcyclohexane, 2 Methyl-l, 3-propanediol, 2,2,4-Trimethylpentandiol-l, 3, dipropylene glycol, polypropylene glycols, dibutylene glycol, polybutylene glycols, bisphenol A, tetrabromo bisphenol A but also lactone-modified diols in question. The diol component preferably contains 40 to 100% by weight of hexanediol, preferably 1,6-hexanediol and / or hexanediol derivatives, preferably those which have ether or ester groups in addition to terminal OH groups, for example products which are obtained by reacting 1 mole of hexanediol with at least 1 mole, preferably 1 to 2 moles of caprolactone or by etherification of hexanediol with itself to di- or trihexylene glycol were obtained. Polyether-polycarbonate diols can also be used. The hydroxyl polycarbonates should be substantially linear. You can, however, if necessary by the Incorporation of polyfunctional components, in particular low molecular weight polyols, can be easily branched. For example, glycerol, trimethylolpropane, hexanetriol-1,2,6, butanetriol-1,2,4, trimethylolpropane, pentaerythritol, quinitol, mannitol, sorbitol, methyl glycoside or 1,3,4,6-dianhydrohexitols are suitable for this purpose.

Suitable polyether polyols corresponding to the definition of the compounds π.2) are the polytetramethylene glycol polyethers known per se in polyurethane chemistry, e.g. can be prepared by polymerization of tetrahydrofuran by cationic Ringöffήung.

In addition, suitable polyether polyols are polyethers, e.g. the polyols prepared from starter molecules using styrene oxide, ethylene oxide, propylene oxide, butylene oxides or epichlorohydrins, in particular of propylene oxide.

The use of polyester polyols and / or polycarbonate polyols is preferred.

The low molecular weight polyols 1.3) or H3) used to build up the polyurethane resins generally cause stiffening and / or branching of the polymer chain. The molecular weight is preferably between 62 and 200. Suitable polyols may include aliphatic, alicyclic or aromatic groups. Mentioned here are, for example, the low molecular weight polyols having up to about 20 carbon atoms per molecule, such as. For example, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,3-butylene glycol, cyclohexanediol, 1,4-cyclohexanedimethanol, 1,6-hexanediol, hydroquinone hydroxyethyl ether, bisphenol A (2,2-bis (4-hydroxyphenyl) propane), hydrogenated bisphenol A (2,2-bis (4-hydroxycyclohexyl) propane) and mixtures thereof, and trimethylolpropane, glycerol or pentaerythritol. Also, ester diols such as e.g. δ-Hydroxybutyl-ε-hydroxy-caproic acid esters, ω-hydroxyhexyl-γ-hydroxybutyric acid esters, adipic acid (β-hydroxyethyl) esters or terephthalic acid bis (β-hydroxyethyl) esters can be used.

Di- or polyamines as well as hydrazides can also be used as 1.3) or π.3), e.g. Ethylenediamine, 1,2- and 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, isophorone diamine, isomer mixture of 2,2,4- and 2,4,4-trimethylhexamethylenediamine, 2-methylpentane methylenediamine, diethylenetriamine, 1,3- and 1,4-xylylenediamine, α, α, α ', α'-tetramethyl-1,3,4,4-diaminodicyclohexylmethane, dimethylethylenediamine, hydrazine or adipic dihydrazide ,

As 1.3) or H.3) are in principle also compounds which contain active hydrogen with respect to NCO groups of different reactivity, such as compounds which in addition to a primary amino group and secondary amino groups, or in addition to an amino group (primary or sekvmdär) also have OH groups. Examples of these are primary / secondary amines, such as 3-amino-1-methylaminopropane, 3-amino-1-ethylaminopropane, 3-amino-1-cyclohexylaminopropane, 3-amino-1-methylaminobutane, furthermore alkanolamines, such as N-aminoethyl- ethanolamine, ethanolamine, 3-aminopropanol, neopentanolamine and more preferably diethanolamine. In the case of use for the preparation of the PU dispersion (I), these are used as chain extenders and in the case of use for the preparation of the PU dispersion (IT) as chain termination.

The polyurethane resin may also optionally contain building blocks 1.4) or H4), which are respectively located at the chain ends and terminate them. These building blocks are derived, on the one hand, from monofunctional compounds reactive with NCO groups, such as monoamines, in particular mono-secondary amines or monoalcohols. Examples which may be mentioned here are: ethanol, n-butanol, ethylene glycol monobutyl ether, 2-ethylhexanol, 1-octanol, 1-dodecanol, 1-hexadecanol, methylamine, ethylamine, propylamine, butylamine, octylamine, laurylamine, stearylamine, isononyloxypropylamine, dimethylamine , Diethylamine, dipropylamine, dibutylamine, N-methylaminopropylamine, diethyl (methyl) aminopropylamine, morpholine, piperidine, or suitable substituted derivatives thereof, amide amines from diprimary amines and monocarboxylic acids, monodime of diprimary amines, primary / tertiary amines, such as N, N-dimethylaminopropylamine and the like.

By ionic or potentially ionic hydrophilizing compounds 1.5) or H5) is meant all compounds which contain at least one isocyanate-reactive group and at least one functionality such as -COOY, -SO ₃ Y, -PO (OY) ₂ (Y, for example = H , NH ₄ ⁺ ,

Metal cation), -NR ₂ , -NR ₃ ⁺ (R = H, alkyl, aryl), which upon interaction with aqueous media undergoes a pH-dependent dissociation equilibrium and to this

May be negative, positive or neutral. Preferred isocyanate-reactive groups are hydroxyl or amino groups.

Suitable ionically or potentially ionically hydrophilic compounds according to the definition of component 1.5) or H5) are, for example, mono- and dihydroxycarboxylic acids, mono- and diaminocarboxylic acids, mono- and dihydroxysulfonic acids, mono- and diaminosulfonic acids and mono- and dihydroxyphosphonic acids or mono- and diaminophosphonic acids and their salts, such as dimethylolpropionic acid, dimethylolbutyric acid, hydroxypivalic acid, N- (2-aminoethyl) -β-alanine, 2- (2-aminoethylamino) -ethanesulfonic acid, ethylenediamine-propyl- or -butylsulfonic acid, 1,2- or 1,3-propylenediamine-β-ethylsulfonic acid, malic acid, citric acid, glycolic acid, lactic acid, glycine, alanine, taurine, lysine, 3,5-diaminobenzoic acid, an addition product of PDI and acrylic acid (EP-A 0 916 647, Example 1 ) and its alkali and / or ammonium salts; the adduct of sodium bisulphite with butene-2-diol-1, 4, polyethersulfonate, the propoxylated adduct of 2-butenediol and NaHSO ₃ , for example described in DE-A 2 446 440 (page 5-9, For¬ mel I-iπ ) as well as compounds which can be converted into cationic groups, for example amine-based, components such as N-methyldiethanolamine as hydrophilic constituent components. Furthermore, cyclohexylaminopropanesulfonic acid (CAPS) can be used, for example, in WO-A 01/88006 as a compound corresponding to the definition of component 1.5) or II.5).

Preferred ionic or potential ionic compounds 1.5) are those which have carboxy or carboxylate and / or sulfonate groups and / or ammonium groups. Particularly preferred ionic compounds 1.5) are those which contain carboxyl and / or sulfonate groups as ionic or potentially ionic groups, such as the salts of N- (2-aminoethyl) -β-alanine, the 2- (2-amino-ethylamino) ) ethanesulfonic acid or the addition product of IPDI and acrylic acid (EP-A 0 916 647, Example 1) and the dimethylolpropionic acid.

Preferred ionic or potential ionic compounds II.5) are those which have carboxy and / or carboxylate groups. Particularly preferred ionic compounds π.5) are dihydroxycarboxylic acids, very particular preference is given to α, α-dimethylolalkanoic acids, such as 2,2-dimethylolacetic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolpentanoic acid or dihydroxysuccinic acid.

Suitable nonionically hydrophilicizing compounds according to the definition of the component 1.6) or π.6) are e.g. Polyoxyalkylene ethers containing at least one hydroxy or amino group. These polyethers contain from 30% to 100% by weight of building blocks derived from ethylene oxide.

Nonionically hydrophilizing compounds are, for example, monohydric polyalkylene oxide polyether alcohols having a statistical average of 5 to 70, preferably 7 to 55 ethylene oxide units per molecule, as are obtainable in a conventional manner by alkoxylation of suitable starter molecules (eg in Ullmanns Encyclopadie der technischen Chemie, 4 Edition, Volume 19, Verlag Chemie, Weinheim pp. 31-38).

Suitable starter molecules are, for example, saturated monoalcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, the isomers pentanols, hexanols, octanols and nonanols, n-decanol, n-dodecanol, n-tetradecanol, n Hexadecanol, n-octadecanol, cyclohexanol, the isomeric methylcyclohexanols or hydroxymethylcyclohexane, 3-ethyl-3-hydroxymethyloxetane or tetrahydrofurfuryl alcohol, diethylene glycol monoalkyl ethers such as diethylene glycol monobutyl ether, unsaturated alcohols such as allyl alcohol, 1,1-dimethylallylalcohol or oleic alcohol, aromatic alcohols such as phenol, the isomeric cresols or Methoxyphenols, araliphatic alcohols such as benzyl alcohol, anisalcohol or cinnamyl alcohol, secondary monoamines such as dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, bis (2-ethylhexyl) amine, N-methyl- and N-ethylcyclohexylamine or dicyclohexylamine and heterocyclic secondary amines such as morpholine, pyrrolidine, piperidine or 1H-pyrazole. Preferred starter molecules are saturated monoalcohols. Particular preference is given to using diethylene glycol monobutyl ether as starting molecule.

Alkylene oxides which are suitable for the alkoxylation reaction are, in particular, ethylene oxide and propylene oxide, which can be used in any desired order or else as a mixture in the alkoxylation reaction.

The polyalkylene oxide polyether alcohols are either pure polyethylene oxide polyethers or mixed polyalkylene oxide polyethers whose alkylene oxide units consist of at least 30 mol%, preferably at least 40 mol%, of ethylene oxide units. Preferred nonionic compounds are monofunctional mixed polyalkylene oxide polyethers which have at least 40 mol% of ethylene oxide and not more than 60 mol% of propylene oxide units.

For the PU polymers (I) it is preferred to use a combination of ionic and nonionic hydrophilicizing agents according to the definitions of components 1.5) and 1.6). Particular preference is given to combinations of nonionic and anionic hydrophilic agents.

The PUR polymers (D) preferably have a pure ionic hydrophilization according to the definition of the components π.5).

Preference is given to 5 to 45 wt .-% of component 1.1), 50 to 90 wt .-% of component 1.2), 1 to 30 wt .-% of the sum of compounds 1.3) and 1.4), 0 to 12 wt .-% of component 1.5 ), 0 to 15% by weight of component 1.6), the sum of 1.5) and 1.6) being 0.1 to 27% by weight and the sum of all components adding to 100% by weight.

Particularly preferred are 10 to 40 wt .-% of component 1.1), 60 to 85 wt .-% of component 1.2), 1 to 25 wt .-% of the sum of compounds 1.3) and 1.4), 0 to 10 wt .-% component 1.5), 0 to 10 wt .-% component 1.6) is used, wherein the sum of 1.5) and 1.6) is 0.1 to 20 wt .-% and the sum of all components added to 100 wt .-%.

Very particular preference is given to 15 to 40% by weight of component L1), 60 to 82% by weight of component 1.2), 1 to 20% by weight of the sum of compounds 1.3), 0 to 8% by weight of component 1.5) , 0 to 10 wt .-% of component 1.6), wherein the sum of 1.5) and 1.6) is 0.1 to 18 wt .-% and the sum of all components added to 100 wt .-%. The coating compositions according to the invention comprise PU polymers (T) which are used in the form of their aqueous PU dispersion (I).

The process for the preparation of the aqueous PU dispersion (I) can be carried out in one or more stages in homogeneous or in multistage reaction, partly in disperse phase. After completely or partially carried out polyaddition from Ll) - 1.6) takes place a dispersing, emulsifying or dissolving step. This is followed, if appropriate, by a further polyaddition or modification in disperse phase.

For the preparation of the aqueous polyurethane dispersions (I), all known from the prior art methods such as. Example, prepolymer mixing process, acetone process or Schmelzdiper- be used. The PU dispersion (I) is preferably prepared by the acetone process.

For the preparation of the polyurethane dispersion (T) by the acetone process are usually the ingredients 1.2) to 1.6), which may have no primary or secondary amino groups and the polyisocyanate component Ll) for the preparation of an isocyanate-functional polyurethane prepolymer completely or partially submitted and optionally diluted with a water-miscible but isocyanate-inert solvent and heated to temperatures in the range of 50 to 120 ⁰ C. To accelerate the isocyanate addition reaction, the catalysts known in polyurethane chemistry can be used. Preference is given to dibutyltin dilaurate.

Suitable solvents are the usual aliphatic, ketofunctional solvents, e.g. Acetone, butanone, which can be added not only at the beginning of the preparation, but possibly also in parts later. Preferred are acetone and butanone.

Subsequently, the components of Ll) - 1.6), which are optionally not added at the beginning of the reaction, are added.

In the preparation of the polyurethane prepolymer, the molar ratio of isocyanate groups to isocyanate-reactive groups is 1.0 to 3.5, preferably 1.1 to 3.0, particularly preferably 1.1 to 2.5.

The reaction of the components 1.1) - 1.6) to the prepolymer takes place partially or completely, but preferably completely. Thus, polyurethane prepolymers containing free isocyanate groups are obtained in bulk or in solution. After or during the preparation of the polyurethane prepolymers, if this has not yet been carried out in the starting molecules, the partial or complete salt formation of the anionically and / or cationically dispersing groups takes place. In the case of anionic groups, bases such as tertiary amines, for example trialkylamines having from 1 to 12, preferably from 1 to 6, carbon atoms in each alkyl radical are used. Examples of these are trimethylamine, triethylamine, methyldiethylamine, tripropylamine and diisopropylethylamine. The alkyl radicals can also carry hydroxyl groups, for example, as in the dialkylmonoalkanol, alkyldialkanol and trialkanolamines. If appropriate, inorganic bases such as ammonia or sodium or potassium hydroxide may also be used as neutralizing agents. Preference is given to triethylamine, triethanolamine, dimethylethanolamine or diisopropylethylamine.

The molar amount of the bases is between 50 and 100%, preferably between 70 and 100% of the molar amount of the anionic groups. In the case of cationic groups, dimethyl sulphate or succinic acid are used. If only nonionically hydrophilicized compounds 1.6) with ether groups are used, the neutralization step is omitted. The neutralization can also take place simultaneously with the dispersion in which the dispersing water already contains the neutralizing agent.

Subsequently, in a further process step, if not yet done or only partially done, the resulting prepolymer with the aid of aliphatic ketones such as acetone or butanone.

Subsequently, possible NH ₂ - and / or NH-functional components are reacted with the remaining isocyanate groups. This chain extension / termination can be carried out either in a solvent before dispersion, during dispersion or in water after dispersion. The chain extension is preferably carried out in water before dispersion.

If compounds corresponding to the definition of 1.5) with NH ₂ or NH groups are used for the chain extension, the chain extension of the prepolymers preferably takes place before the dispersion.

The degree of chain extension, ie the equivalent ratio of NGO-reactive groups of the compounds used for chain extension to free NCO groups of the prepolymer, is between 40 and 150%, preferably between 70 and 120%, particularly preferably between 80 and 120%. The aminic components [1.3), 1.4), 1.5)] can optionally be used individually or in mixtures in water- or solvent-diluted form in the process according to the invention, wherein basically any order of addition is possible.

If water or organic solvents are used as diluents, the diluent content is preferably 70 to 95% by weight.

The preparation of the PU dispersion (T) from the prepolymers takes place after the chain extension. To this end, the dissolved and chain extended polyurethane polymer is optionally sheared under high shear, e.g. vigorous stirring, either added to the dispersing water or, conversely, the dispersing water is stirred into the prepolymer solutions. Preferably, the water is added to the dissolved prepolymer.

The solvent still present in the dispersions after the dispersion step is then usually removed by distillation. A removal already during the dispersion is also possible.

Depending on the degree of neutralization and content of ionic groups, the dispersion can be adjusted very finely divided, so that it has practically the appearance of a solution, but also very coarse-particle settings are possible, which are also sufficiently stable.

The solids content of the PU dispersion (!) Is between 25 to 65%, preferably 30 to 60% and particularly preferably between 40 to 60%.

Furthermore, it is possible to modify the aqueous PU dispersions (I) by polyacrylates. For this purpose, in these polyurethane dispersions, an emulsion polymerization of olefinically unsaturated monomers, e.g. Esters of (meth) acrylic acid and alcohols having 1 to 18 carbon atoms, styrene, vinyl esters or butadiene performed.

The coating compositions of the invention comprise PU polymers (H), which are either converted into the aqueous form during production and thus present as a dispersion or alternatively also present in a water-miscible and isocyanate-inert solvent as solution.

The crosslinkable polyurethane polymers (H) can be prepared by the usual methods known in the art. They contain carboxylic acid and / or sulfonic acid groups, preferably carboxylic acid groups, which may be at least partially neutralized, as hydrophilic groups. The compounds falling under the components H2) to H6) can also contain C =C double bonds, which can be derived, for example, from long-chain aliphatic carboxylic acids or fatty alcohols. Functionalization with olefinic double bonds is also possible, for example, by the incorporation of allylic groups or of acrylic acid or methacrylic acid and their respective esters.

The preparation of the crosslinkable polyurethane polymers (III) is usually carried out to such an extent that first an isocyanate-functional prepolymer from compounds corresponding to the definition of components ILI) - TL.6) is prepared and in a second reaction step by reaction with compounds corresponding to the definition of the components π .3), π.4) and H5), in non-aqueous medium an OH- and / or NH-functional polyurethane is obtained, such as in EP-A 0 355 682, p. 4, Z. 39-45. However, the preparation can also be carried out such that the OH and / or NH groups-containing polyurethane resin is formed directly by reacting the components ILI) to IL 6) in non-aqueous medium, such. in EP-A 0427 028, S.4, Z. 54 - page 5, Z.l described.

The compounds used to form this prepolymer according to the definition of component II.2) may, but not necessarily, be subjected beforehand to a distillation step under reduced pressure. For this purpose, these compounds are preferably continuously in a thin film evaporator at temperatures> 150 ⁰ C, preferably 170 to 230 ⁰ C, particularly preferably 180 to 220 ⁰ C, under a reduced pressure of <10 mbar, preferably <2 mbar, more preferably < Distilled 0.5 mbar. Low molecular weight, non-reactive volatiles are separated under these conditions. In the distillation, volatile fractions of 0.2 to 15 wt .-%, preferably 0.5 to 10 wt .-%, particularly preferably 1 to 6 wt .-% separated.

The prepolymer preparation is usually carried out at temperatures of 0 ° to 14O ⁰ C, depending on the reactivity of the isocyanate used. Components II.1) and II.2) are preferably used in such a way that an NCO / OH ratio of 0.5 to 0.99 / 1, preferably 0.55 to 0.95 / 1 and particularly preferably 0 , 57 to 0.9 / 1 results.

To accelerate the urethanization reaction, it is possible to use suitable catalysts, as are known to the person skilled in the art for accelerating the NCO / OH reaction. Examples of these are tertiary amines such as triethylamine or diazobicyclooctane, organotin compounds such as dibutyltin oxide, dibutyltin dilaurate or tin bis (2-ethylhexanoate) or other organometallic compounds. The prepolymer preparation is preferably carried out in the presence of isocyanate-inert solvents. For this purpose, in particular those solvents are considered which are compatible with water, such as ethers, ketones and esters and N-methylpyrrolidone. The amount of this solvent expediently does not exceed 30% by weight and is preferably in the range from 10 to 25% by weight, in each case based on the sum of polyurethane resin and solvent.

The acid groups incorporated in the prepolymer thus obtainable are at least partly neutralized. This can be done during or after the prepolymer but also during or after the dispersion in water by adding suitable neutralizing agent (see also in PU dispersion (I)). Example of this is dimethylethanolamine, which preferably serves as a neutralizing agent. The neutralizing agent is usually used in molar ratio to the acid groups of the prepolymer of 0.3: 1 to 1.3: 1, preferably from 0.4: 1 to 1: 1.

The neutralization step is preferably carried out subsequent to the preparation of the prepolymer, wherein in principle at temperatures of 0 to 80 ⁰ C, preferably 40 to 8O ⁰ C is used.

Subsequently, the hydroxy- and / or amino-functional polyurethane is converted by the addition of water or by adding in water in an aqueous dispersion.

The resins of the polyurethane polymers (H) obtainable by the procedure described above have a number-average molecular weight M _{n of} from 1,000 to 30,000, preferably from 1,500 to 10,000, an acid number of from 10 to 80, preferably from 15 to 40 mg, KOH / g and an OH content of 0.5 to 6 wt .-%, preferably from 1.0 to 4 wt .-%.

The PU dispersions (I) and (II) may contain as component I.7) /I1.7) antioxidants and / or light stabilizers and / or other auxiliaries and additives.

Optionally, all light stabilizers and polyurethane dispersions known for polyurethanes or polyurethane dispersions and described, for example, in "light stabilizers for coatings" (A. Valet, Vincentz Verlag, Hannover, 1996) and "Stabilization of Polymeric Materials" may be used as light stabilizers and antioxidants 1.7) or II.7). Optionally used (H. Zweifel, Springer Verlag, Berlin, 1997) described additives. Preferred stabilizers are sterically hindered phenols (phenolic antioxidants) and / or hindered amines based on 2,2,6,6-tetramethylene piperidine (Hindered Amine Light Stabilizers, HALS light stabilizers). In addition, all known for PUR dispersants auxiliaries and additives, such as emulsifiers, defoamers, thickeners may be included in the PU dispersions. Finally, fillers, Plasticizers, pigments, carbon black and silica sols, aluminum, clay, asbestos dispersions are incorporated into the PU dispersions.

Crosslinkers TK) are also present in the coating compositions according to the invention. Depending on the choice of crosslinker, both one-component and two-component coatings can be prepared. In the context of the present invention, one-component paints are to be understood as coating agents in which binder component and crosslinker component can be stored together, without a crosslinking reaction taking place in appreciable or detrimental extent for the subsequent application. The crosslinking reaction takes place only after application after activation of the crosslinker. This activation may e.g. caused by increasing the temperature. For the purposes of the present invention, two-component coatings are to be understood as meaning coating compositions in which the binder component and crosslinking component must be stored in separate vessels because of their high reactivity. The two components are mixed just before application and then generally react without additional activation. In order to accelerate the crosslinking reaction, it is also possible to use catalysts or to use higher temperatures.

Suitable crosslinkers IH) are, for example, blocked or unblocked polyisocyanate crosslinkers, amide and amine-formaldehyde resins, phenolic resins, aldehyde and ketone resins, such as e.g. Phenol-formaldehyde resins, resoles, furan resins, urea resins, carbamic acid ester resins, triazine resins, melamine resins, benzoguanamine resins, cyanamide resins, aniline resins, as described in "Lackkunstharze", H. Wagner, H.F. Sarx, Carl Hanser Verlag Munich, 1971. Preference is given to polyisocyanates.

Polyisocyanates with free isocyanate groups are particularly preferably used as crosslinkers of component IH), since the aqueous polyurethane coatings obtained show a particularly high paint-technical level. Suitable crosslinkers JS) are, for example, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane, hexamethylene diisocyanate, 1,4-diisocyanatocyclohexane or bis (4-isocyanatocyclohexane) -methane or l, 3- (bis-2 isocyanatopropyl-2) benzene or polyisocyanates of hexamethylene diisocyanate, isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane or bisphenol polyisocyanates based on lacquer polyisocyanates, such as uretdione, biuret, isocyanurate or iminooxadiazinedione groups. (4-isocyanatocyclohexane) -methane or urethane-containing lacquer polyisocyanates based on 2,4- and / or 2,6-diisocyanate cyanatotoluene or l-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane on the one hand and low molecular weight polyhydroxyl compounds such as trimethylolpropane, the isomeric propanediols or butanediols or any mixtures of such polyhydroxyl compounds on the other. Likewise provided by the present invention is a two-component lacquer comprising the inventive Beschichrungsmittel.

Optionally, the said compounds containing free isocyanate groups can be converted by reaction with so-called blocking agents into less reactive derivatives, which then react only after activation, for example at higher temperatures. Suitable blocking agents for these polyisocyanates are, for example, monohydric alcohols such as methanol, ethanol, butanol, hexanol, cyclohexanol, benzyl alcohol, oximes such as acetoxime, methyl ethyl ketoxime, cyclohexanone oxime, lactams such as ε-caprolactam, phenols, amines such as diisopropylamine or dibutylamine, Dimethylpyrazole or triazole and dimethyl malonate, diethyl malonate or dibutyl malonate.

Very particular preference is given to the use of low-viscosity, hydrophobic or hydrophilic polyisocyanates of the abovementioned type with free isocyanate groups based on aliphatic, cycloaliphatic, araliphatic and / or aromatic isocyanates, preferably aliphatic or cycloaliphatic isocyanates, since this results in a particularly high level of resistance of the paint film leaves. These polyisocyanates generally have a viscosity of from 10 to 3,500 mPas at 23 ^° C.

If necessary, the polyisocyanates may be used in admixture with small amounts of inert solvents to lower the viscosity to a value within the stated range. Also Triisocyanatononan can be used alone or in mixtures in component JS).

The PUR polymers I) and II) described here are generally sufficiently hydrophilic, so that the dispersibility of hydrophobic crosslinkers from component HI) is ensured. If desired, however, it is also possible to add additional external emulsifiers as are known to the person skilled in the art.

However, it is also possible to use water-soluble or dispersible polyisocyanates, as described, for example, in US Pat. by modi¬ fication with carboxylate, sulfonate and / or polyethylene oxide groups and / or polyethylene oxide / polypropylene oxide groups are available in component JS) can be used.

In principle, of course, it is also possible to use mixtures of different crosslinker resins of the abovementioned type in component TU).

Further film-forming resins of component IV) are water-dispersible, emulsifiable or soluble polymers which differ from the constituents of components I) to HCT). Examples of these are, if appropriate, polyesters containing epoxide groups, polyols urethanes, acrylic polymers, vinyl polymers such as polyvinyl acetate, polyurethane dispersions, polyacrylate dispersions, polyurethane-polyacrylate hybrid dispersions, polyvinyl ether or polyvinyl ester dispersions, polystyrene or polyacrylonitrile dispersions. The solids content of the film-forming resins of component IV) is preferably 10 to 100 wt .-%, particularly preferably 30 to 100 wt .-%.

Likewise provided by the present invention is a process for preparing the aqueous coating compositions according to the invention, characterized in that the PU polymers (I) and the PU polymers (II) are dispersed in water and crosslinked with the crosslinker (DI) and optionally with the fibriform resins W) are mixed.

It is likewise possible for the PUR polymers (II) to be present as a solution in a water-miscible solvent which is inert toward isocyanate groups and converted into the aqueous phase by introduction into the PUR dispersion (I) and subsequently crosslinked with the crosslinker (III). and optionally with the film-forming resins PV).

The ratio of the crosslinker IH) to the reactive with him compounds of the components H) and optionally PV) is to be chosen so that a ratio of relative to the crosslinker reactive groups of H) and W) (eg OH groups) to the reactive groups of the crosslinker (in the case of isocyanate NCO groups) of 0.5: 1.0 to 3.5: 1.0, preferably 1.0: 1.0 to 3.0: 1.0 and particularly preferably of 1.0: 1.0 to 2.5: 1.0 results.

The mixture of components I), II) and W) preferably contains 5 to 95 wt .-%, particularly preferably 25 to 75 wt .-% of component II), wherein the amounts of I) and W) are to be chosen so the total amounts of I), H) and W) add up to 100% by weight.

As customary auxiliaries and additives, the substances known to the person skilled in the art, such as defoaming agents, thickeners, pigments, dispersing agents, matting agents, catalysts, anti-skinning agents, anti-settling agents and / or emulsifiers, as well as additives which enhance the desired soft feel effect, can be present in the coating compositions according to the invention , It is irrelevant at what point in the production of these added to the coating compositions of the invention or incorporated into this.

The aqueous coating compositions according to the invention are suitable for all fields of use in which aqueous coating and coating systems with high surface finish requirements of the films are used, eg coating of mineral building material surfaces, painting and sealing of wood and wood-based materials, coating of metallic surfaces (metal coating ), Coating and painting asphalt or bituminous coatings, varnishing and sealing of various plastic surfaces (plastic coating) as well as high gloss varnishes.

However, a preferred use of the coating compositions according to the invention is the production of soft feel effect paints, which ensure good hydrolysis resistances with very good haptic properties. Such coating agents are preferably lacquered in the plastics or the used timber coating, the curing is usually carried out at temperatures between room temperature and 130 ⁰ C. The two-component technology with non-blocked polyisocyanates as crosslinkers allows the use of comparatively low curing temperatures in the above-mentioned interval.

Softfeel paints containing the coating compositions according to the invention are thus also the subject of the present invention.

The aqueous coating compositions of the invention are usually used in single-coat paints or in the clearcoat or topcoat (top coat) of multi-layered structures.

The coating can be produced by the various injection methods, such as, for example, air-pressure, airless or electrostatic spray methods, using one-component or optionally two-component spray systems. However, the lacquers and coating compositions containing the binder dispersions according to the invention can also be applied by other methods, for example by brushing, rolling or knife coating.

The present invention likewise relates to a multi-layer structure, characterized in that the uppermost layer, which is a clear or topcoat layer, contains a soft feel coating containing the coating compositions according to the invention.

Examples:

Unless otherwise indicated, all percentages are by weight.

Substances used and abbreviations:

Diaminosulphonate: NH ₂ -CH ₂ CH ₂ -NH-CH ₂ CH ₂ -SO ₃ Na (45% in water)

Bayhydrol ^® XP 2429: Aliphatic, hydroxyfunctional polyester polyurethane dispersion with a solids content of 55% (Bayer AG, Leverkusen, Germany)

Bayhydrol ^® XP 2441: Aliphatic hydroxyfunctional polyester polyurethane resin, 75% in

N-methylpyrolidone (Bayer AG, Leverkusen, DE)

Desmophen ^® 2020: polycarbonate polyol, OH number 56 mg KOH / g, number-average molecular weight 2000 g / mol (Bayer AG, Leverkusen, DE)

PolyTHF ^® 2000: Polytetramethylenglykolpolyol, OH number 56 mg KOH / g, number average molecular weight 2000 g / mol (BASF AG, Ludwigshafen, DE)

PolyTHF ^® 1000: Polytetramethylenglykolpolyol, OH number 112 mg KOH / g, zahlen¬ average number average molecular weight 1000 g / mol (BASF AG, Ludwigshafen, DE)

Polyether LB 25: (monofunctional polyether based on ethylene oxide / propylene oxide number-average molecular weight 2250 g / mol, OH number 25 mg KOH / g (Bayer AG, Leverkusen, DE)

BYK 348: Wetting agent (BYK-Chemie, Wesel, DE)

Tego-Wet ^® KL 245: Leveling additive, 50% in water (Tegochemie, Essen, DE)

Aquacer ^® 535: wax emulsion (BYK-Chemie, Wesel, DE)

Defoamer DNE: Defoamer (K. Obermayer, Bad Berleburg, DE)

Sillitin ^® Z 86: filler (Hoffmann & Sons, Neuburg, DE)

Pergopak ^® M 3: filler, matting agent (Martinswerk, Bergheim, DE)

Talkum ^® IT extra: matting agent (Norwegian Tale, Frankfurt, DE)

Bayferrox ^® 318 M: Color pigment (black) (Bayer AG, Leverkusen, DE) OK 412: matting agents (Degussa, Frankfurt, DE)

Bayhydur ^® 3100: Hydrophilic aliphatic polyisocyanate based on hexamethylene diisocyanate (HDI) having an isocyanate content of 17.4% (Bayer AG, Leverkusen, DE)

Bayhydur ^® VPLS 2306: Hydrophil modified, aliphatic polyisocyanate based on

Hexamethylene diisocyanate (HDI) with an isocyanate content of 8.0% (Bayer AG, Leverkusen, DE)

Desmodur ^® XP 2410: Low viscosity, aliphatic polyisocyanate resin based Hexa¬ diisocyanate having an isocyanate content of 24.0% (Bayer AG, Leverkusen, Germany)

MPA: l-methoxy-2-propyl acetate

The solids contents were determined according to DESf-EN ISO 3251.

NCO contents were determined volumetrically in accordance with DIN-EN ISO 11909, unless expressly stated otherwise.

Example 1 ; Comparative Example (Component I)

Bayhydrol ^® PR 240: anionically hydrophilized PUR dispersion based on polyester

Solids content of 40% and an average particle size of 100-300 nm (Bayer AG, Leverkusen, DE)

Example 2 Non-functional PU Dispersion (Component I)

144.5 g of Desmophen ^® 2020 188.3 g PolyTHF ^® 2000, 71.3 g PolyTHF ^® 1000 and 13.5 g of polyether LB 25 were heated to 70 ⁰ C. Subsequently, a mixture of 59.8 g of hexamethylene diisocyanate and 45.2 g of isophorone diisocyanate is added at 70 ^° C. in the course of 5 minutes and the mixture is stirred under reflux until the theoretical NCO value is reached. The finished prepolymer is dissolved with 1040 g of acetone at 50 ⁰ C and then added a solution of 1.8 g of hydrazine hydrate, 9.18 g of diaminosulfonate and 41.9 g of water within 10 min. The stirring time is 10 min. After adding a solution of 21.3 g of isophorone diamine and 106.8 g of water is dispersed within 10 min by adding 395 g of water. This is followed by removal of the solvent by distillation in vacuo and a storage-stable dispersion having a solids content of 50.0% is obtained. The following performance engineering experiments for the production of softfeel coatings are carried out using Examples 1-2.

The parent lacquer is prepared by predispersion by trituration over a laboratory shaker. The temperature of the ground material should not exceed 40 ^° C. Then stir in O 412 for approx. 10 min. After crosslinking, the paint system is set to a flow time of approx. 30 s (DIN ISO 2431, 5 mm nozzle) and conventionally sprayed onto Bayblend ^® T 65. The dry film thickness is between 30 and 40 μm.

Table 1 Application Examples 3-8 (according to the invention)

Application condition: approx. 23 ° C and 55% rel. Humidity. Drying condition: 10 min / RT, 30 min / 80 ⁰ C and about 16h / 6O ⁰ C aging TABLE 2 APPLICATION EXAMPLES 9-14 (COMPARATIVE EXAMPLES)

Application condition: approx. 23 ⁰ C and 55% rel. Humidity.

Drying condition: 10 min / RT, 30 min / 80 ⁰ C and about 16h / 60 ⁰ C aging Table 4 Hydrolysis resistance after 72 h at 90 ⁰ C and about 90% rel. humidity

¹ pencil hardness test:

The pencil hardening method is a test for determining the paint film hardness. Pencils of different hardness (6B to 7H) on painted specimens are tested at room temperature as follows: The pencil tip is ground horizontally to give a flat, round surface. At an angle of 45 °, the pencil is then pushed over the paint film to be tested, whereby a force that is as constant as possible should be applied. The value of pencil hardness is determined when the paint surface is damaged for the first time.

² determined according to DIN EN ISO 2409 (O = best value, 5 = worst value)

³ Film softening test (fingernail sample):

The film softening is determined by means of the film nail sample. The assessment of the

Softening through the fingernail test is as follows: not scratchable = 0 (best value) scratch-through to the substrate = 5 (worst value)

⁴ 0 = okay; 1 = occasionally bright spots; 2 = bright spots; 3 = many bright spots

The results from Table 4 show that both the coatings according to the invention (Example 3-8) and the comparative coatings (Examples 9-14) have an excellent feel and approximately the same coating hardness. After 72 h of hydrolysis at 90 ⁰ C and 90% relative humidity show the comparative example, however, considerable Filmerweichungen (degradation by hydrolysis), the coatings whereas from the inventive Examples 3-8 show no softening.

Claims

Patentansprfiche

1. containing aqueous coating agent

(I) hydroxyl-free polyurethanes and / or polyurethane ureas based on polycarbonate polyols and polytetramethylene glycol polyols,

(II) ionically modified, hydroxyl and / or amino-containing polyurethanes and / or polyurethane ureas and

(JS) at least one crosslinker as well

(IV) optionally further fibrous resins.

2. Coating composition according to claim 1, characterized in that component (Q) is a polyurethane polymer based on a polyester urethane and / or a polycarbonate natpolyols.

3. Coating composition according to claim 1, characterized in that the polyurethane polymer (I) contains a combination of ionic and nonionic hydrophilicizing agents.

4. Coating composition according to claim 1, characterized in that the polyurethane polymer (I) contains a combination of nonionic and anionic Hydrophilierungs¬ agents.

5. Coating composition according to claim 1, characterized in that the polyurethane polymer (I) has a pure ionic hydrophilization.

6. Coating composition according to claim 1, characterized in that the polyurethane polymer (JI) has a number average molecular weight M _n of 1000 to 30,000, an acid number of 10 to 80 mg KOH / g and an OH content of 0.5 to 6 wt .-% having.

7. Coating composition according to claim 1, characterized in that the crosslinker (JS) is a polyisocyanate with free isocyanate groups based on aliphatic or cycloaliphatic isocyanates.

8. A process for the preparation of the aqueous Beschichtungsmitel according to claim 1, characterized in that the PU polymers (I) and the PU polymers (H) dispersed in water and mixed with the crosslinker (JS) and optionally with the film-forming resins rV) become.

9. A process for the preparation of the aqueous Beschichtungsmitel according to claim 1, characterized in that the PU polymers (It) are present as a solution in a water-miscible and isocyanate-inert solvent and by being introduced into the PU dispersion (T) in the aqueous Phase transferred and then mixed with the crosslinker (IH) and optionally with the film-forming resins IV).

10. The method according to claim 8 or 9, dadruch CHARACTERIZED in that the ratio of the crosslinker HI) to the reactive with him compounds of the components II) and optionally IV) is to be chosen so that a ratio of crosslinkable to the crosslinker groups from D) and IV) to the reactive groups of the crosslinker from 0.5: 1.0 to 3.5: 1.0 results.

11. Two-component paint containing the coating composition according to claim 1 and 7.

12. Use of the coating composition according to claim 1 for the coating of mineral building material surfaces, metallic surfaces or coatings containing asphalt or bitumen, painting and sealing of wood and wood-based materials or plastic surfaces or as high-gloss lacquer.

13. Use of the coating composition according to claim 1 for the production of soft-shell coatings on plastic or wood substrates.

14. Softfeel lacquer containing the coating composition according to claim 1.

15. Multi-layer structure, characterized in that the uppermost layer, which is a clear or topcoat layer, contains a softfeel lacquer according to claim 12.