HK1178552B

HK1178552B - Aqueous polyurethane-polyurea dispersions

Info

Publication number: HK1178552B
Application number: HK13105555.1A
Authority: HK
Inventors: J．明特尔; T．菲舍
Original assignee: 斯塔尔国际有限公司
Priority date: 2010-05-25
Filing date: 2011-04-27
Publication date: 2015-09-04

Description

Aqueous polyurethane polyurea dispersions

The present invention relates to aqueous polyurethane polyurea dispersions and to a process for their preparation, which can be used as part of a coating for flexible flat substrates. Which improves the soiling performance and the cleanability of the flexible substrate.

The preparation of aqueous polyurethane polyurea dispersions by means of the prepolymer ionomer process or the acetone process has been known for a long time, for example from prog. In this document, an isocyanate group-containing prepolymer is prepared in bulk or in solution and is optionally dissolved in a solvent after the reaction has been carried out. Subsequently, the prepolymer or prepolymer solution is dispersed in water and a chain extension reaction is carried out with a polyamine. The propagation reaction may be carried out partly or also completely before the dispersion. Finally, the solvent is optionally distilled off.

WO-2009/144157 discloses a process for preparing foam-stabilized aqueous polyurethane polyurea dispersions, in which

A) An NCO-group-containing polyurethane prepolymer having an NCO-functionality of more than 1 and less than 2 is first produced by the reaction of:

A1) polyisocyanates and

A2) polymeric polyols and/or polyamines having a number average molecular weight of 400 to 8000g/mol,

A3) isocyanate-reactive, non-ionic hydrophilic compounds,

A4) isocyanate-reactive, aliphatic group-containing compounds,

A5) optionally low molecular weight compounds having a number average molecular weight of 17 to 400g/mol selected from the group consisting of monoalcohols and polyols, monoamines and polyamines and aminoalcohols,

A6) optionally isocyanate-reactive, ionic or potentially ionic hydrophilic compounds,

A7) optionally in an aliphatic ketone or ester as solvent,

B) reacting the still free NCO groups of the prepolymer with isocyanate-reactive monoamines, polyamines, hydrazine and/or hydrazides such that the ratio of isocyanate-reactive NH groups to NCO groups is from 0.8 to 1.2, wherein

C) Optionally dissolving the prepolymer obtained from step a) in an aliphatic ketone or ester, provided that the preparation is carried out in the presence of a7), optionally diluting the prepolymer solution by adding an aliphatic ketone or ester.

Starting from the prior art, the object of the present invention is to provide an adhesive which improves the soiling properties of flexible flat substrates, in particular leather. Furthermore, the adhesive should improve the cleanability of the flexible flat substrate, in particular leather.

It has now surprisingly been found that polyurethane polyurea dispersions derived from the reaction of polyisocyanates with isocyanate-reactive compounds having at least one polysiloxane group achieve this object.

The present invention therefore relates to a process for preparing aqueous polyurethane-polyurea dispersions, in which

A) Firstly, NCO-group-containing polyurethane prepolymers are produced by reaction of

A1) Polyisocyanates and

A2) polymeric polyols and/or polyamines having a number average molecular weight of more than 400 to 8000g/mol,

A3) optionally low molecular weight compounds having a number average molecular weight of 17 to 400g/mol selected from the group consisting of monoalcohols and polyols, monoamines and polyamines and aminoalcohols,

A4) isocyanate-reactive, ionic or potentially ionic hydrophilic compounds and/or isocyanate-reactive non-ionic hydrophilic compounds,

A5) isocyanate-reactive compounds containing at least one C₇To C₂₄Alkyl or C₇To C₂₄Alkenyl, and

A6) an isocyanate-reactive compound containing at least one polysiloxane group,

and

B) reacting the still free NCO-groups of the prepolymer with isocyanate-reactive monoamines, polyamines, hydrazine and/or hydrazides such that the calculated ratio of isocyanate-reactive NH-groups to NCO groups amounts to 0.7 to 1.2.

Of importance to the invention is the reaction of the isocyanate with the isocyanate-reactive compound comprising polysiloxane groups, with the isocyanate with the compound containing C₇To C₂₄Alkyl or C₇To C₂₄The reaction of the alkenyl isocyanate-reactive compound is combined.

The invention further relates to the use of the polyurethane polyurea dispersions produced according to the invention for providing stain resistance and easy-to-clean properties to flexible flat substrates.

The invention also relates to a method for providing flexible flat substrates with stain resistance and easy-to-clean properties by applying the polyurethane polyurea dispersions according to the invention to flexible flat substrates, in particular leather.

Another subject of the invention is an aqueous polyurethane polyurea dispersion which can be prepared according to the above process.

Suitable polyisocyanates according to A1 are of the formula X (NCO)_pWherein p is a number greater than 1 to 4, preferably 2 to 3, particularly preferably 2, and X is an aliphatic, cycloaliphatic, aromatic or araliphatic hydrocarbon radical. Preferably, X is an aliphatic hydrocarbon group having 3 to 20 carbon atoms, a cycloaliphatic hydrocarbon group having 5 to 15 carbon atoms, an aromatic hydrocarbon group having 6 to 15 carbon atoms, or an araliphatic hydrocarbon group having 7 to 15 carbon atoms. If the formula X (NCO) is used_pIs a mixture of compounds having different numbers of isocyanate groups, then p is the average number of isocyanate groups present.

Examples of diisocyanates are tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1, 4-diisocyanatocyclohexane, 1-isocyanato-3, 5, 5-trimethyl-5-isocyanatomethylcyclohexane (IPDI), 2-bis- (4-isocyanatocyclohexyl) -propane, trimethylhexane diisocyanate, 1, 4-diisocyanatobenzene, 2, 4-diisocyanatotoluene, 2, 6-diisocyanatotoluene, 4 ' -diisocyanatodiphenylmethane, 2,4 ' -diisocyanatophenylmethane, p-xylylene diisocyanate, tetramethylxylylene diisocyanate (TMXDI), isomers of 4,4 ' -diisocyanatodicyclohexylmethane such as trans/trans-, the formal/formal and the formal/trans isomers and mixtures of these compounds.

Polymeric polyols or polyamines according to A2) are generally derived from hydroxyl-or amino-containing polycarbonates, polyesters, polyethers, polyacrylates, polyolefins and polysiloxanes, such as are known, for example, from Ullmann's Encyclopedia of Industry Chemistry 2005, DOI:10.1002/14356007.a 21-665. pub2 "polyurethanes", chapter 3, W.Friederichs.

Suitable polycarbonate polyols are, for example, those which can be obtained by reaction of phosgene with an excess of polyol. Suitable diols are, for example, ethylene glycol, 1, 2-propanediol, 1, 3-propanetriol, 1, 2-butanediol, 1, 3-butanediol, 1, 4-butenediol, 1, 4-butynediol, 1, 5-pentanediol, neopentyl glycol, 2-butyl-2-ethyl-1, 3-pentanediol, bis (hydroxymethyl) -cyclohexanes, such as 1, 4-bis (hydroxymethyl) cyclohexane, 2-methylpropane-1, 3-diol, methylpentanediol, and also diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol and polybutylene glycol.

Preferred are compounds of the formula HO- (CH)₂)_xAlcohols of-OH, where x is a number from 1 to 20, preferably an even number from 2 to 20. Examples of such ions are ethylene glycol, 1, 4-butanediol, 1, 6-hexanediol, 1, 8-octanediol and 1, 12-dodecanediol. Further preferred are neopentyl glycol and 2-butyl-2-ethyl-1, 3-propanediol. It is also possible to use proportions of more polyhydric alcohols such as, for example, glycerol, trimethylolpropane, 1,2, 6-hexanetriol, 1,2, 4-butanetriol, pentaerythritol, p-cyclohexanediol, mannitol and sorbitol.

Furthermore, polyester polyols are also contemplated, which are obtained by reaction of polyols with polycarboxylic acids. Instead of the free polycarboxylic acids, it is also possible to useThe corresponding polycarboxylic anhydrides or mixtures thereof are used to prepare the polyester polyols. The polycarboxylic acids may be aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic and optionally substituted (for example by halogen atoms) and/or unsaturated. Mention may be made here, as examples: suberic acid, azelaic acid, phthalic acid, isophthalic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, endomethylenetetrahydrophthalic anhydride, glutaric anhydride, maleic acid, maleic anhydride, fumaric acid, dimeric fumaric acid. Preferred is a compound of formula HOOC- (CH)₂)_yDicarboxylic acids of-COOH, wherein y is a number from 1 to 20, preferably an even number from 2 to 20, such as succinic acid, adipic acid, sebacic acid and dodecanedioic acid. As polyols, preferably diols, the low molecular weight alcohols mentioned as building blocks for polycarbonate polyols come into consideration.

Also suitable are polyester diols based on lactones, preferably addition products of lactones with terminal hydroxyl groups with suitable polyfunctional starter molecules. Preferred lactones are those of the general formula HO- (CH)₂)_zThose of compounds of the formula-COOH, where z is a number from 1 to 20 and the H-atom of the methylene unit may also be replaced by C₁To C₄Alkyl substitution. The ion is epsilon-caprolactone, beta-propiolactone, gamma-butyrolactone and/or methyl-epsilon-caprolactone ethyl, and mixtures thereof. Suitable starter components are, for example, the low molecular weight polyols mentioned above as building components for polycarbonate polyols. Polymers of the corresponding epsilon-caprolactone are particularly preferred. Also lower polyester diols or polyether diols can be used as starting materials for the preparation of the lactone polymers. Instead of the polymers of lactones it is also possible to use corresponding, stoichiometric amounts of polycondensates of the hydroxycarboxylic acids corresponding to the lactones.

Polyether diols are also suitable as polyols. They may be prepared in particular by reacting ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, styrene oxide, epichlorohydrin or partially or perfluorinated derivatives of these compounds with themselves, for example in BF₃In the presence of (A), orObtained by adding these compounds, optionally in admixture or one after the other, to a starting component having a reactive hydrogen atom, such as an alcohol or an amine, for example water, ethylene glycol, 1, 2-propanediol, 1, 3-propanediol, 1, 2-bis (4-hydroxydiphenyl) -propane or aniline.

Likewise suitable are polyhydroxyolefins, preferably those having 2 terminal hydroxyl groups, such as α -, ω -dihydroxypolybutadiene, α -, ω -dihydroxypolymethacrylate or α -, ω -dihydroxypolyacrylate, as monomers. These compounds are known, for example, from EP0622378a 1. Other suitable polyols are polyacetals, polysiloxanes and alkyd resins.

Suitable low molecular weight compounds according to A3) are the low molecular weight polyols mentioned above as building blocks for polycarbonate polyols, preferably diols and triols.

Furthermore, monohydric or secondary alcohols are also contemplated, preferably primary or secondary alcohols, such as, for example, methanol, ethanol, propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, 1-hexanol, 1-octanol, 2-ethylhexanol, 1-decanol, 1-dodecanol, 1-tetradecanol, 1-hexadecanol, 1-octadecanol and 1-eicosanol.

Also suitable are amines or amino alcohols which are obtained, for example, by exchanging the alcohol radical of the alcohols mentioned in the last two paragraphs with amino or monoalkylamino groups.

Ionic or potentially ionic hydrophilic compounds according to a4) mean compounds which all have at least one group reactive toward isocyanates, preferably a hydroxyl or amino group, and at least one ionic or potentially ionic functionality. The ions of the ionic and potentially ionic groups being-COOY, -SO₃Y、-PO(OY)₂(Y e.g. ═ H, NH₄ ⁺Metal cation), -NR₂、-NR₃ ⁺(R = H, alkyl, aryl). Suitable ionically or potentially ionically hydrophilicizing compounds are known to the person skilled in the art and are described, for example, in DE102004002526A1 in paragraph [0032]As set forth or illustrated herein.

Isocyanate-reactive, nonionic hydrophilic compounds according to A4) are polyoxyalkylene ethers which contain at least one hydroxyl or amino group. Suitable nonionic hydrophilic compounds are known to the person skilled in the art and are proposed or elucidated, for example, in DE102004002526a1 in paragraphs [0035] to [0039] or also in DE102006036220a 1.

The isocyanate-reactive, alkyl-or alkenyl-containing compounds according to A5) are compounds containing at least one isocyanate-reactive group (such as, for example, an alcohol, amine or thiol) and at least one C₇To C₂₄Alkyl or alkenyl compounds. These include, for example, alkyl-or alkenyl-containing monoalcohols or dialcohols, monoamines or diamines and aminoalcohols. Likewise included in this class are alkoxylation products of aliphatic carboxylic acids, carboxamides, phosphoric monoesters, phosphoric diesters, phosphonic acids, phosphonic monoesters, sulfuric monoesters, sulfonic acids, monohydric or dihydric alcohols or diamines.

In a preferred embodiment, component A5) contains at least one compound of the formula (1)

Wherein

X' represents O, S, NH or NR,

a ', B' independently of one another denote a hydrocarbon radical having 1 to 30 carbon atoms, which may optionally contain heteroatoms selected from N, O, P and/or S, and which is not reactive toward isocyanates,

n represents a number from 6 to 23, preferably from 10 to 21, in particular from 14 to 19,

k represents 1 or 2.

Preferably, monohydroxy-, dihydroxy-, and monoamine compounds containing aliphatic hydrocarbon groups are used. The aliphatic hydrocarbon groups present are preferably unbranched. Particularly preferred are saturated, unbranched alkyl groups having 11 to 22 carbon atoms. Particularly preferred are saturated, unbranched alkyl groups having 15 to 20 carbon atoms.

Examples of compounds according to A5) are 1-octanol, 1-decanol, 1-dodecanol, 1-hexadecanol, 1-octadecanol, oleyl alcohol, 1-eicosanol, and also their alkoxylates (prepared, for example, by addition reaction of ethylene oxide and/or propylene oxide). Preference is given to using alkoxylates having less than 9 alkoxy units.

Further examples are 1-octylamine, 1-decylamine, 1-dodecylamine, 1-hexadecylamine, 1-octadecylamine, oleylamine, 1-eicosylamine, and also alkoxylates thereof (prepared, for example, by addition of ethylene oxide and/or propylene oxide), where the amine nitrogen is monosubstituted and/or disubstituted by alkoxylation. Preference is given to using alkoxylates having less than 13 alkoxy units.

The compounds according to A5) may also be carboxylic acid alkoxylates or carboxylic acid dialkoxides (for example prepared from octanoic acid, decanoic acid, dodecanoic acid, hexadecanoic acid, octadecanoic acid, oleic acid, eicosanoic acid, octanoyl amide, decanoyl amide, dodecanoic amide, hexadecanoid amide, octadecanoic amide, oleamide or eicosanoid with, for example, ethylene oxide and/or propylene oxide). Preference is given to using alkoxylates having less than 10 alkoxy units.

Further examples are monoesters or diesters made from phosphoric acid and, for example, 1-octanol, 1-decanol, 1-dodecanol, 1-hexadecanol, 1-octadecanol, oleyl alcohol, 1-eicosanol or monoesters made from sulfuric acid and, for example, 1-octanol, 1-decanol, 1-dodecanol, 1-hexadecanol, 1-octadecanol, oleyl alcohol, 1-eicosanol and addition products of, for example, ethylene oxide and/or propylene oxide to these esters. Preference is given to using alkoxylates having less than 10 alkoxy units.

Furthermore, alkoxylated aliphatic phosphonic acids, phosphonic monoesters and sulfonic acids can be used, whose substituents on phosphorus or on sulfur and also the ester groups can be, for example, 1-octyl, 1-decyl, 1-dodecyl, 1-hexadecyl, 1-octadecyl, oleyl or 1-eicosyl, and their alkoxylation is carried out, for example, with ethylene oxide and/or propylene oxide. Preferably, alkoxylates having less than 10 alkoxy units are used.

Also possible are mono-ethers (e.g.1-octyl ether, 1-decyl ether, 1-dodecyl ether, 1-hexadecyl ether, 1-octadecyl ether, oleyl ether or eicosyl ether), trifunctional alcohols (e.g.glycerol, trimethylolpropane, pyrogallol, phloroglucinol and 1,2, 6-hexanetriol) and also alkoxylates prepared by addition of, for example, ethylene oxide and/or propylene oxide to these ethers. Preferably, alkoxylates having less than 10 alkoxy units are used.

It is likewise possible to use, for example, monoesters with octanoic, decanoic, dodecanoic, hexadecanoic, octadecanoic, oleic or eicosanoic acid and trifunctional alcohols, such as glycerol, trimethylolpropane, pyrogallol, phloroglucinol and 1,2, 6-hexanetriol, and also alkoxylates, which are prepared by addition of, for example, ethylene oxide and/or propylene oxide to these esters. Preference is given to using alkoxylates having less than 10 alkoxy units.

It is likewise possible to use, for example, dicarboxylic esters of octanoic acid, decanoic acid, dodecanoic acid, hexadecanoic acid, octadecanoic acid, oleic acid or rather acids with tetrafunctional alcohols (for example pentaerythritol, erythritol, threitol or diglycerol), and also alkoxylates (prepared by addition of, for example, ethylene oxide and/or propylene oxide to these esters). Preference is given to using alkoxylates having less than 10 alkoxy units.

Other examples are diesters or diamides of dihydroxydicarboxylic acids (e.g.from tartaric acid and 1 octanol, 1-decanol, 1-dodecanol, 1-hexadecanol, 1-octadecanol, oleyl alcohol, 1-eicosanol, 1-octylamine, 1-decylamine, 1-dodecylamine, 1-hexadecylamine, 1-octadecylamine, oleylamine or 1-eicosylamine), and also alkoxylates (prepared by addition of, for example, ethylene oxide and/or propylene oxide to esters or amides). Preference is given to using alkoxylates having less than 10 alkoxy units.

It is particularly preferred that component A5) contains a compound of formula (2)

Ingredient a6) is an isocyanate-reactive compound which contains at least one polysiloxane group.

In a preferred embodiment of the invention, these compounds contain polysiloxane structural units of the formula (3)

Wherein R and R' are hydrocarbyl groups and n has an average value of 3 to 55.

It is further preferred that R and R' are alkyl or aryl groups and that n has an average value of from 3 to 25. It is particularly preferred that R and R' are methyl or phenyl and n has an average value of 6 to 20.

It is further preferred that component A6) contains at least one compound of the formula 4)

Wherein

X is O, S, NH or NR,

A. b, B' are, independently of one another, hydrocarbon radicals having from 1 to 30 carbon atoms, which may optionally contain heteroatoms from the group N, O, P and/or S, and which are not reactive toward isocyanates,

m is a number from 3 to 55, preferably from 4 to 25, in particular from 6 to 20.

In the process of the present invention, for the preparation of the NCO-group containing polyurethane prepolymers, it is preferred to react from 10 to 45% by weight of component A1), from 30 to 80% by weight of component A2), from 0 to 10% by weight of component A3), from 0.1 to 20% by weight of component A4), from 0.1 to 20% by weight of component A5) and from 0.1 to 20% by weight of component A6), the sum of all components adding to 100% by weight. In another preferred embodiment, at least 0.1% by weight of a3) is used.

The process of the invention generally comprises a step in which component a1) is mixed with components a2) to a6) and optionally a solvent below the reaction temperature. The order of addition of component a1), component a2) to a6) and optionally solvent is arbitrary. The reaction of component A1) and components A2) to A6) is preferably initiated by an increase in temperature. Preferred solvents are ketones or esters, particularly preferred are copolyols or methyl acrylate. The reaction is preferably carried out at a temperature in the range of 50 to 120 ℃.

The reaction of the component a1) and the components a2) to a6) can be carried out in the presence of a solvent or in bulk. In a preferred embodiment of the present invention, the isocyanate group-containing prepolymers consisting of component a1) and components a2) to a6) are prepared in bulk or in solution and are optionally dissolved in a solvent after the reaction has been carried out. The prepolymer or prepolymer solution is then dispersed in water on hand. Preference is given here to adding the prepolymer or prepolymer solution to the pre-established water or to adding water to the pre-established prepolymer solution and carrying out the chain extension reaction with polyamines according to step B). The propagation reaction may be carried out partly or also completely before the dispersion. Finally, the solvent is optionally distilled off.

The process of the invention for preparing the aqueous PUR dispersions can be carried out in one or more steps in homogeneous phase or, in the case of a multi-stage reaction, in part in dispersed phase. After the complete or partial addition polymerization of A1) to A6), a dispersing step, an emulsifying step or a dissolving step is carried out. Subsequently, further polyaddition reactions or modifications are optionally carried out in the dispersed phase.

Catalysts known for promoting the isocyanate addition reaction in the process of the invention, such as, for example, triethylamine, 1, 4-diazabicyclo- [2.2.2] -octane, dibutyltin oxide, tin dioctoate or dibutyltin dilaurate, tin bis (2-ethylhexanoate) or other organometallic compounds, are metered in together, in advance or afterwards.

The components A1) to A6) which were optionally not added at the beginning of the reaction were then metered in.

In the preparation of the polyurethane prepolymers, the molar mass ratio of the total amount of isocyanate groups from a1) to the total amount of isocyanate-reactive groups from a2) to a6) in step a) is from 1.0 to 3.5 and preferably from 1.2 to 2.7.

The reaction of components A1) to A6) to form the prepolymer takes place partly or completely, but preferably completely. The conversion is usually monitored by tracking the NCO content of the reaction mixture. For this purpose, either spectroscopic measurements of the extracted sample, for example infrared or near-infrared spectroscopy, for determining the refractive index, or chemical analyses, for example titration, can be carried out. A polyurethane prepolymer containing free isocyanate groups is thus obtained.

After or during the preparation of the polyurethane prepolymers from a1) to a6), the groups which act as anionic and/or cationic dispersing groups are completely or partially salified if this is not yet carried out on the starting molecules. In the case of anionic groups, bases such as ammonia, ammonium carbonate or ammonium bicarbonate, trimethylamine, triethylamine, tributylamine, diisopropylethylamine, dimethylethanolamine, diethylethanolamine, triethanolamine, potassium hydroxide or sodium carbonate are used for this purpose, preferably triethylamine, triethanolamine, dimethylethanolamine or diisopropylethylamine. The molar mass of the base is between 50 and 150% and preferably between 85 and 120% of the no mass of the anionic groups. In the case of cationic groups, dimethyl sulfate, succinic acid or formic acid are used. If only the nonionic hydrophilic compound a3 having an ether group is used), the neutralization step is omitted. Neutralization can also be carried out simultaneously with the dispersion, the water already containing the neutralizing agent by dispersion.

Reacting the compounds from B) with the remaining isocyanate groups in a subsequent process step. The chain growth/-termination here can be carried out in a solvent before the dispersion, during the dispersion or preferably in water after the dispersion.

In step B), amino alcohols, mono-, di-or polyamines and hydrazine or hydrazides are used to convert the NCO groups which are still free. Monofunctional compounds used for the chain extension reaction may be aminoalcohols and monoamines, such as those mentioned under A3), preferably aminoalcohols or long-chain monoamines, such as, for example, ethanolamine, diethanolamine, 1-hexylamine, 1-octylamine, 1-decylamine, 1-dodecylamine, 1-tetradecylamine, 1-hexadecylamine, 1-octadecylamine, 1-eicosylamine. As di-or polyfunctional compounds there may be used, for example, ethylenediamine, 1, 2-and 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 6-diaminohexane, isophoronediamine, 2, 4-and 2,4, 4-trimethylthiomethylene diamine, 2-methyl-pentamethylenediamine, piperazine, 2, 5-dimethylpiperazine, 4,4 ' -diaminocyclohexylmethane, 1, 4-diaminocyclohexane, aminoethylethanolamine, aminopropylethanolamine, (2-aminoethyl) -2-aminoethylsulfonic acid sodium salt, diethylenetriamine, triethylenetetramine, tetraethylpentamine, 1, 3-and 1, 4-xylylenediamine, α, α ', α ' -tetramethyl-1, 3-and 1, 4-xylylenediamine and 4, 4' -diaminodicyclohexylmethane, dimethylethylenediamine, hydrazine, adipic acid dihydrazide or oxalic acid dihydrazide.

The degree of chain extension, i.e.the equivalent ratio of the reactive NH groups of the freshly added compounds for chain extension in B) to the free NCO groups in the prepolymer, is preferably between 0.8 and 1.2.

In the process of the invention, the compounds B) can be used individually or in admixture, optionally diluted with water and/or solvents, where in principle any order of addition is possible.

The polyurethane polyurea dispersions of the invention are preferably prepared by introducing the solvent-free or dissolved prepolymer or chain-extended polyurethane polymer, optionally under intense shear (such as, for example, vigorous stirring), into the dispersing water or, conversely, stirring the dispersing water into the prepolymer or polymer or solution thereof.

The dispersions thus obtained have a solids content of from 10 to 70% by weight, preferably from 20 to 65% by weight and particularly preferably from 25 to 60% by weight.

Depending on the degree of neutralization and the content of ionic groups, the dispersion can be adjusted to be very fine-grained, so that it has virtually the appearance of a solution, but also very coarse-grained adjustments which are sufficiently stable are possible.

The invention also relates to mixtures of the polyurethane polyurea dispersions according to the invention with other aqueous binders and crosslinkers for producing coating agents. Auxiliaries and additives known per se from paint technology, such as, for example, thickeners, fillers, pigments, waxes, texture agents (griffmitel), dyes, solvents, flow aids and crosslinking agents, can also be used here. Particularly preferred auxiliaries and additives are nanoparticles, partially or perfluorinated polymers and silicones. Particularly preferred auxiliaries and additives are those described in the following documents: DE4328917, DE102004040266, DE19649953, WO2005/078182, US6171515, US4599438, US5385999, DE 4240274.

Another subject matter of the invention is the coating of the polyurethane polyurea dispersions of the invention and/or their mixtures described above on any substrates, such as, for example, metal, wood, glass fibers, carbon fibers, stone, ceramic minerals, concrete, various types of hard and flexible plastics, textiles and non-woven textiles, leather, split leather, imitation leather, paper, hard fibers, straw and asphalt, which are optionally also provided with conventional primers before coating or optionally with further coatings after coating.

Preferred substrates are leather and artificial leather. Particularly preferred substrates are full grain and ground leather and split leather.

The polyurethane polyureas of the invention contain those of formula (5) as the most important structural element

Therein, the

X, X' independently of one another denote O, S, NH, NR,

A. a ', B, B', B '' independently of one another denote a hydrocarbon radical having 1 to 30 carbon atoms, which optionally may contain heteroatoms selected from N, O, P and/or S and which is not reactive toward isocyanates,

m represents a number from 3 to 55, preferably from 4 to 25, in particular from 6 to 20,

PUR stands for polyurethane polyureas, which are formed by reaction of components a1), a2), A3), a4) and B).

If the structural units of inserts (2) and (4) are inserted, the structure of equation (6) is obtained when X = O

Examples

Comparative example PU-1:

190.3g (95mmol) of polycarbonate diol based on hexanediol (OHZ = 56) and 14.1g (105mmol) of dimethylolpropionic acid are initially introduced at 60 ℃ and 85.5g (385 mmol) of isophorone diisocyanate are added. The mixture was stirred at about 90 ℃ for 3 hours. Thereafter, the NCO value was 5.26% (calculated NCO value: 5.36%). To the prepolymer was added 150g of methyl acrylate and the solution was cooled to 30 ℃. 10.6g (105mmol) of triethylamine are subsequently added and 484g of cold water are added to the prepolymer solution over 5 minutes with vigorous stirring and stirring for a further 10 minutes. To the dispersion obtained a solution of 8.62g (172.4mmol) hydrazine monohydrate (corresponding to 95% of the calculated necessary diamine amount) in 50g of water was added over 5 minutes and stirring was continued for 10 minutes. The methyl acrylate was subsequently distilled off under vacuum and the solids content adjusted to 35% by weight with water.

Example of the invention PU-2:

190.3g (95mmol) of polycarbonate diol based on hexanediol (OHZ = 56), 17.4g (130 mmol) of dimethylolpropionic acid, 15.0g (15 mmol) of alpha- ((3- (2, 2-bis (hydroxymethyl) -butoxy) -propyl) -dimethylsilyl-omega- ((butyldimethylsilyl) -oxy) -poly (dimethylsiloxane) having a molecular weight of 1000g/mol and 18.8g (21.5 mmol) of diglycerol distearate ethoxylated on average with 4 ethylene oxide units are preset at 60 ℃ and 108.8g (490 mmol) of isophorone diisocyanate are added, the mixture is stirred for 3 hours at about 90 ℃ after which the NCO-value is 5.03% (calculated NCO-value: 5.50%). 200g of methyl acrylate are added to the prepolymer and the value is cooled to 30 ℃ followed by 13.6g (135 mmol) of triethylamine and 577g of cold water are added over 5 minutes with vigorous stirring The prepolymer solution was stirred for an additional 10 minutes. To the dispersion obtained a solution of 10.0g (199.7 mmol) hydrazine monohydrate (corresponding to 95% of the calculated necessary diamine amount) in 50g of water was added over 5 minutes and stirring was continued for 10 minutes. The methyl acrylate is subsequently distilled off under vacuum and the solids content is adjusted to 35% by weight with water.

Leather, which has been treated with a commercially available primer for automotive leather and a beige colored coating, was used to compare stain and cleaning performance.

The following composition was applied as a top coat by spraying:

topcoat T1:

500g of water, 360gPU-1, 40g of a water-dispersible crosslinker containing isocyanate groups, the isocyanate functionality of which is > 3.

Topcoat T2:

500g of water, 360gPU-2, 40g of a water-dispersible crosslinker containing isocyanate groups, the isocyanate functionality of which is > 3.

Application of T1 or T2 was carried out by spraying twice with a spray gun so that there was about 15g/m on the leather, respectively²The undried top coat of (a). The coating was dried in a drying tunnel between spray applications.

Soil pick-up and cleaning performance were tested according to the following test guidelines of the automotive industry association: "VDA 230-Leder, Kunststoffbahnenwaren und textilie fur Krafffahrzeuge-Bestimung des Anschmutz-undReinigungsverhaltens-Verfahren mit Anschmutzgewebe". The constituents of the test guidelines are evaluated for the degree of soiling according to ISO 105-A03 (grey scale), where the soiled leather is evaluated visually. The degree of staining is given on the scale of 1 (strongly stained) to 5 (not stained). The evaluation of the stainability was performed immediately after the staining. For the evaluation of the cleaning performance, the test specimens were cleaned and reevaluated 24 hours after soiling, corresponding to the test guidelines.

The degree of staining achieved with the leather treated with T1 was 1. The degree of staining after cleaning was 2.

The leather lane treated with T2 was between 2 and 3 in duty. The degree of standing after cleaning was 4.

Claims

1. Process for preparing aqueous polyurethane-polyurea dispersions, in which

A1) Polyisocyanates and

A6) an isocyanate-reactive compound comprising at least one compound of formula (4),

wherein

X is O, S, NH or NR,

A. b, B' are each independently a hydrocarbyl group having 1 to 30 carbon atoms, which may optionally contain heteroatoms selected from N, O, P and/or S, and which are not isocyanate-reactive,

m is a number of from 3 to 55,

and in which the polysiloxane groups introduced by component A6) are present as side chains,

and

2. The process as claimed in claim 1, wherein C is introduced via component A5)₇To C₂₄Alkyl or C₇To C₂₄The alkenyl group exists as a side chain.

3. The method of claim 1 or 2, wherein

C) The prepolymer obtained from step A) is prepared in an aliphatic ketone or ester and/or is dissolved or diluted in an aliphatic ketone or ester after the reaction in step A).

4. The process of claim 1 or 2, wherein component a1) is a diisocyanate.

5. A process as claimed in claim 3, wherein component a1) is a diisocyanate.

6. The process of claim 1,2 or 5, wherein component A1) is an aliphatic diisocyanate.

7.A process as claimed in claim 3, wherein component a1) is an aliphatic diisocyanate.

8. The process of claim 4, wherein component A1) is an aliphatic diisocyanate.

9. The process of any one of claims 1,2, 5, 7 and 8, wherein more than 95 mol% of components a2) to a6) consists of a compound having one or two groups reactive with isocyanates, wherein carboxylic acid groups are considered as being non-reactive with isocyanates.

10. The process of claim 3, wherein more than 95 mol% of components A2) to A6) consist of compounds having one or two groups reactive toward isocyanates, wherein carboxylic acid groups are regarded as being non-reactive toward isocyanates.

11. The process of claim 4, wherein more than 95 mol% of components A2) to A6) consist of compounds having one or two groups reactive toward isocyanates, wherein carboxylic acid groups are regarded as being non-reactive toward isocyanates.

12. The process of claim 6, wherein more than 95 mol% of components A2) to A6) consist of compounds having one or two groups reactive toward isocyanates, wherein carboxylic acid groups are regarded as being non-reactive toward isocyanates.

13. The process as claimed in any of claims 1,2, 5, 7, 8 and 10-12, wherein the NCO-group-containing polyurethane prepolymer is obtained by reaction of from 10 to 45% by weight of component a1), from 30 to 80% by weight of component a2), from 0 to 10% by weight of component A3), from 0.1 to 20% by weight of component a4), from 0.1 to 20% by weight of component a5) and from 0.1 to 20% by weight of component a6), where the sum of all the components adds up to 100% by weight.

14. The process as claimed in claim 3, wherein the NCO-group-containing polyurethane prepolymer is obtained by reaction of from 10 to 45% by weight of component A1), from 30 to 80% by weight of component A2), from 0 to 10% by weight of component A3), from 0.1 to 20% by weight of component A4), from 0.1 to 20% by weight of component A5) and from 0.1 to 20% by weight of component A6), the sum of all the components adding to 100% by weight.

15. The process as claimed in claim 4, wherein the NCO-group-containing polyurethane prepolymer is obtained by reaction of from 10 to 45% by weight of component A1), from 30 to 80% by weight of component A2), from 0 to 10% by weight of component A3), from 0.1 to 20% by weight of component A4), from 0.1 to 20% by weight of component A5) and from 0.1 to 20% by weight of component A6), the sum of all the components adding to 100% by weight.

16. The process as claimed in claim 6, wherein the NCO-group-containing polyurethane prepolymer is obtained by reaction of from 10 to 45% by weight of component A1), from 30 to 80% by weight of component A2), from 0 to 10% by weight of component A3), from 0.1 to 20% by weight of component A4), from 0.1 to 20% by weight of component A5) and from 0.1 to 20% by weight of component A6), the sum of all the components adding to 100% by weight.

17. The process as claimed in claim 9, wherein the NCO-group-containing polyurethane prepolymer is obtained by reaction of from 10 to 45% by weight of component a1), from 30 to 80% by weight of component a2), from 0 to 10% by weight of component A3), from 0.1 to 20% by weight of component a4), from 0.1 to 20% by weight of component a5) and from 0.1 to 20% by weight of component a6), wherein the sum of all the components adds up to 100% by weight.

18. The process of any of claims 1,2, 5, 7, 8, 10-12 and 14-17, wherein the compound according to a5) contains at least one unbranched alkyl or alkenyl chain of 7 to 24 carbons.

19. The process as claimed in claim 3, wherein the compound according to A5) contains at least one unbranched alkyl or alkenyl chain of 7 to 24 carbons.

20. The process as claimed in claim 4, wherein the compound according to A5) contains at least one unbranched alkyl or alkenyl chain of 7 to 24 carbons.

21. The process as claimed in claim 6, wherein the compound according to A5) contains at least one unbranched alkyl or alkenyl chain of 7 to 24 carbons.

22. The process as claimed in claim 9, wherein the compound according to a5) contains at least one unbranched alkyl or alkenyl chain of 7 to 24 carbons.

23. The process as claimed in claim 13, wherein the compound according to a5) contains at least one unbranched alkyl or alkenyl chain of 7 to 24 carbons.

24. The process as claimed in claim 18, wherein the compound according to a5) contains at least one unbranched, saturated alkyl chain of 11 to 22 carbons.

25. The process of any of claims 19 to 23, wherein the compound according to a5) contains at least one unbranched, saturated alkyl chain of 11 to 22 carbons.

26. The process as claimed in claim 24, wherein the compound according to a5) contains at least one unbranched, saturated alkyl chain of 15 to 20 carbons.

27. The process as claimed in claim 25, wherein the compound according to a5) contains at least one unbranched, saturated alkyl chain of 15 to 20 carbons.

28. The method of any one of claims 1,2, 5, 7, 8, 10-12, 14-17, 19-24, 26, and 27, wherein in the compound according to a6), m is 4 to 25.

29. The process as claimed in claim 3, wherein in the compounds according to A6), m is from 4 to 25.

30. The process as claimed in claim 4, wherein in the compounds according to A6), m is from 4 to 25.

31. The process as claimed in claim 6, wherein in the compounds according to A6), m is from 4 to 25.

32. The process as claimed in claim 9, wherein in the compounds according to a6), m is from 4 to 25.

33. The process as claimed in claim 13, wherein in the compounds according to a6), m is from 4 to 25.

34. The process as claimed in claim 18, wherein in the compounds according to a6), m is from 4 to 25.

35. The process as claimed in claim 25, wherein in the compound according to a6), m is from 4 to 25.

36. The method of any one of claims 1,2, 5, 7, 8, 10-12, 14-17, 19-24, 26, and 27, wherein in the compound according to a6), m is from 6 to 20.

37. The process as claimed in claim 3, wherein in the compounds according to A6), m is from 6 to 20.

38. The process as claimed in claim 4, wherein in the compounds according to A6), m is from 6 to 20.

39. The process as claimed in claim 6, wherein in the compounds according to A6), m is from 6 to 20.

40. The process as claimed in claim 9, wherein in the compounds according to a6), m is from 6 to 20.

41. The process as claimed in claim 13, wherein in the compounds according to a6), m is from 6 to 20.

42. The process as claimed in claim 18, wherein in the compounds according to a6), m is from 6 to 20.

43. The process as claimed in claim 25, wherein in the compound according to a6), m is from 6 to 20.

44. An aqueous polyurethane polyurea dispersion obtainable by the process of any one of claims 1 to 43.

45. Use of an aqueous polyurethane polyurea dispersion according to claim 44 for the preparation of coatings.

46. Coating obtainable from an aqueous polyurethane polyurea dispersion according to claim 45.

47. A substrate coated with the coating of claim 46.

48. A flexible planar substrate coated with the coating of claim 46.

49. The substrate of claim 48, wherein the substrate is leather or artificial leather.

50. The substrate of claim 49, wherein the leather is full grain leather, buffed leather, or split leather.