MXPA96000073A - Aqueous dispersion of polyurethanes containing siloxan lines, producing them and using compositions of revestimie - Google Patents

Abstract

The present invention relates to an aqueous dispersion of one or more polyurethane resins, characterized in that the polyurethane resin: a) has a number average molecular weight (Mn) of 2,500 to 1,000,000, b) contains siloxane bonds, c) contains water dispersing portions selected from the group consisting of ionic groups, groups convertible to ionic groups, hydrophilic groups and any combination thereof, d) do not have hydroxysilyl, alkoxysilyl or alkanoyloxysilyl groups in an amount sufficient to cause entanglement; it has essentially no isocyanate group subsequent to the formation of the siloxane bonds or the groups derived from the isocyanate groups, and f) is linear or branched, and ungelled but chain-extended by the siloxane bonds, the bonds of siloxane in a content of 2 to 150 mmol of siloxane bonds per 100 g of solid resin, and the dispersing portions of water are n present in an amount of 5 to 200 mEq per 100 g of resin Sóli

Description

AQUEOUS DISPERSION OF POLYURETHANES CONTAINING SILOXAN LINKS. PRODUCTION OF THE SAME AND USE IN COATING COMPOSITIONS This invention relates to aqueous polyurethane dispersions (PU dispersions), to a process for the production thereof, to water-based coating compositions containing the polyurethane dispersions, and - * 1 use of them for the production of multilayer lacquer coating. A multitude of differently understood polyurethane dispersions of chain have been known. Due to their relevant properties they have found particular industrial applications as binders in aqueous bake lacquers. Thus, for example, EP-A-O 0 &9 W97, EP-A-O 22β 003, DE-A-3Ó 26 121+ and EP-AO 5J.2 52 «+ describe lacquers for baths containing aqueous polyurethane dispersions as the binder, which can be produced by chain extension of the functional isocyanate prepolymers with polyamine and / or polyol. DE-A-39 15? +59 provides examples of aqueous basecoats containing aqueous polyurethane dispersions as the binder, which can be produced by chain extension of functional isocyanate prpolymers with water. Examples of water-based lacquers based on aqueous polyurethane dispersions, which can be produced by chain extension with reactive polyisocyanate polyisocyanate PU polyisocyanates containing active hydrogen, can be found in DE-A-39 03 d0l * and DE-A Multilayer lacquer coatings produced using water-based base lacquers formulated in bake to known polyurethane dispersions require improvements with respect to their resistance to watercontained. If known polyurethane dispersions are used as the sole binder in water-based basecoats, the development of the resulting effect is less favorable compared to aqueous basecoats containing at least one additional co-glue. EP-A-0 163 214 discloses aqueous self-entangling polyurethane dispersions with preferably side silicone groups. PU dispersions are produced and stored under conditions that deliberately prevent the siliconate groups from reacting with each other. After application, the binders are entangled by condensation of the siliconate groups to form siloxane bonds. Additional aqueous solutions or dispersions of polyurethanes with reactive silicone groups suitable for crosslinking are known from EP-AO 315 006. The binders described therein are synthesized by the reaction of the isocyanate groups of the isocyanate prepolymers with amino groups , that is, the extension of adena "occurs by means of amino groups, a large amount of water is added during the production of the agants, so that, in accordance with the law of mass action, virtually no water is produced. The object of the present invention is to provide novel aqueous polyurethane dispersions, which, when used as binders in aqueous coating compositions, in particular in lacquers, of aqueous bake, require the production of coatings of polyurethane. multi-layered lacquer with improved resistance to condensed water When the water-based lacquers are used they contain As the only binder PU dispersion to be provided, the development of the resulting effect within the multilayer lacquer coatings should meet the current requirements for automotive lacquer coating. This object is achieved by the provision of aqueous polyurethane dispersions based on a polyurethane resin with an average molecular weight (Mn of 2500 to 1000000, a content of 2 to 150 mmol, preferably 3 to 100 mmol, particularly preferably of 7 to 70 mmol of siloxane bonds (-Si-0-Si-) per 100 g of solid resin, a hydroxyl value of from 0 to 100, preferably higher than less than 60 mg K'GH / g in relation to the solid resin and a content of ionic groups, groups that are converted into ionic groups and / or hydrophilic groups of 5 to 200 Eq per 100 g of solid resin. The polyurethane resins according to the invention are of a linear or branched structure or are in the form of microgels In the PU dispersion according to the invention, 5 to 200 mEq (milliequivalents) of ionic groups, groups which They are converted into ionic groups and / or hydrophilic groups are present per 100 grams of solid resin.If the groups that are converted to ionic groups are acidic groups, or if the ionic groups are anionic, then - "3C above 15 and below 100, particularly above 18 and below 60 mEq / 100 grams of solid resin are preferably present in a particular manner, if the groups that are converted into ionic groups are basic groups , or if the ionic groups are cationic, then preferably more than 30 and less than 150, particularly more than 45 and less than 100 mEq / 100 g of solid resin will be present. / _ In the hydrophilic groups, 5 to 200 mEq it refers to the lower molecular weight components of such groups, such as for example to alkylene oxide units in polyalkylene oxide groups, for example to ethylene oxide groups in polyethylene oxide groups (such units are known also as repeating units.) Examples of ionic groups and groups that are converted into ionic groups and hydrophilic groups contained in the PU dispersion according to the invention can be found in the following specification, which refers, '* the production of dispersion, PU. The present invention also provides a process for the production of aqueous dispersions of polyurethane resins, which process is characterized in that a polyurethane prepolymer containing ionic groups, groups capable of ion formation and / or hydrophilic groups, whose prepolymer has at less a R'OSu- group, in which, R '= C ± a C? alkyl or C (0) R '' 'and R' '' CJ.-C..O alkyl, and which may be present in the presence of an organic solvent, is subjected to the chain extension by adding at least a stoichiometric amount of water to hydrolyze the SiOR 'groups, converting the reaction product during or after the extension of catitana ^ optionally after neutralizing complete or partial, in an aqueous dispersion and optionally removing any solvent present by distillation, wherein the proportions of the individual educts are selected in such a way that the finished polyurethane resins satisfy the above-mentioned specifications with respect to the definition of dispersions. The complete amount of water needed for the production of the dispersion can be used for the hydrolysis and the consequent chain extension. Preferably, however, the hydrolysis proceeds initially with a quantity jf ^ nr of water preferably of up to 10 times of excess estequeométrico, preferably of up to 5 times of excess estequeométrico, calculated in relation to the amount of water necessary to hydrolyze the groups R ' Or if. The production of polyurethane (PU) prepolymers with R'OSi groups using the process according to the invention can proceed, for example by: 1) production of a linear or branched ungelled functional polyurethane polyurethane prepolymer , which contains ionic groups, groups capable of forming ion and / or hydrophilic groups in an organic solvent or in the absence of solvents, 2) reaction of the free isocyanate groups of the PU prepolymer with one or more compounds of the general formula ((H-X -), R) .Si (0R ') to (R "> _- (I) with X = 0, S, NH or NR V, preferably NH or NR'V R = a difunctional, trifunctional or tetrafunctional organic residue with a molecular weight of 13 to 500, preferably alkylene (ar) with 1 to 12 carbon atoms. carbon, particularly alkylene with 1 to 12 carbon atoms, R '= alkyl of 1 to ß carbon atoms or C (0) R' '', preferably alkyl of 1 to 4 carbon atoms. R "= R '' '= alkyl of 1 10 carbon atoms, where R" and R '' 'can be identical or different, v = alkyl of 1 carbon atoms a = 1, 2 or 3, preferably 1, b = 1, 2 or 3, preferably 2 or 3, c = 0, 1 or 2, n = 1 to 3, preferably 1 or 2, particularly 1 wherein two or more residues R ", R" and R "'can be identical or different and wherein the sum of a + b + c is four, optionally mixed with one or more alkanolamines possessing >• • NH-B and / or NH-groups with an OH functionality of at least 1. The chain extension of the R'OSi prepolymers functionalized with PU proceeds after the addition of preferably up to 10 times of excess The amount of water required for hydrolysis of the SiOR 'groups is stoichiometric. The hydrolysis of the R'OSi groups proceeds rapidly. The HOSi group formed by hydrolysis condense with the elimination of water to form the siloxapo ace so that in an extended chain polyurethane resin whose groups contain virtually no R'OSi and diagonally HOSi, ie those groups are present in such a small amount that they may not effect entanglement. The optionally neutralized reaction product can be converted to an aqueous dispersion by the addition of a sufficient amount of water during or after extension of the caplet. The extension of the chain proceeds in the resin phase; in this way, if the resin is already dispersed by the addition of a sufficient amount of ¡Ua, the chain extension proceeds within the particles of the dispersion. Any solvent optionally present can be optionally removed from the aqueous dispersion by distillation. In the process according to the invention the proportions of the individual educts are selected in such a way that the finished polyurethane resin contains 2 to "50 mmol, preferably 3 to 100 mmol, preferably particularly 7 to 70 mmol of siloxane bond (Si-0-Si-) per 100 g of solid resin, has an average molecular weight number (Mn) from 2500 to 1000000, a hydrox value from 0 to 100, preferably from 0 to 60 mg KOH / g in relation to the solid resin and a content of ionic groups, groups convertible into ionic groups and / or hydrophilic groups of 5 to 200 mEq per 100 g of solid resin. • "&": - As an alternative to the sequential production process by means of NCO prepolymers described above, the PU pre-polymers functionalized with R'OSi can also be produced in a single-stage process, i.e. the process steps 1 and 2 described above can be run simultaneously by reacting the necessary educts with each other simultaneously When selecting the reactive agents, care must be taken to ensure that the reactivity of the -XH functional groups is not impaired.

The functional and non-gelled linear or branched isocyanate PU prepolymer containing ionic groups, groups capable of ion formation and / or hydrophilic groups, will be described hereinafter as the polyurethane prepolymer containing NCO groups, which is for example in process step 1, it can for example be produced by reacting 1 or more compounds having at least the reactive isocyanate groups, in particular 1 more polyols, in particular diols, with one or more organic polyisocyanates, preferably diisocyanates, and with one or more compounds having more than one, preferably two, groups of reactive iso ianatoe and at least one ionic group, group capable of formation of ion and / or hydrophobic group. For example, according to the invention, a polyurethane prepolymer containing NCO groups usable as a starting material for the production of the dispersion * -. PU according to the present invention can be produced by the reaction in an anhydrous environment of a) at least one linear or branched compound, which possesses at least two groups of reactive isocyanates with an average molecular weight of 60 to 10000, preferably from 60 to 6000. b) at least one organic polyisocyanate, in particular diisocyanate, c) at least one compound with more than one reactive isocyanate group and at least one ionic group, a peace ion formation group and / or hydrophilic group with an average molecular weight number (Mn) of up to 10000, preferably of up to 200 in an NC0 / 0H ratio, above 1 to 4: 1. According to a preferred embodiment of the invention, the aforementioned component a) linear or branched compound is at least one polyol based on one or more polyethers, polyesters and / or polycarbonates having at least two OH groups per molecule and one molecular weight number x to edium (Mn) of 600 to 10000, preferably above 1000 and below 5000, optionally together 1 or more at least of difunctional lower molecular weight alcohols and / or amines and / or amine alcohols with a molecular weight below 600, preferably below 400. All production processes for the preparation of polyurethane prepolymers containing NCO groups can be carried out as simple or single stage procedures. The PU prepolymer containing the isocyanate groups preferably has a content of urethane groups (-NHC-100) and optionally urea (-NHC0NH) of between 10 and 300 milliequivalents per 100 g of solid resin. The preparation of the aqueous polyurethane dispersion according to the invention can be carried out as any stage without organic solvents. The compounds used as component a) for the production of PU prepolymer containing NCO groups can beFor example, a linear or branched polyol component, for example diols. These are, for example, polyols used in PU chemistry known to persons skilled in the art. The examples are described in DE-A-42 2 510. If a linear diol component is used as the starting material, the proportions of polyols with a functionality of 3 or more can be added to achieve the polymer branching. The Amount selected here may be such that gelation occurs during the synthesis of the PU prepolymer containing NCO groups. Suitable diols are, for example, diols derived from fatty alcohols. Higher fatty alcohols with &; at 22 carbon atoms can, for example, also be dimerized or trimerized to form long chain polyols. The long chain polyol is preferably a , and particularly a C3 dimer diol < s > preferably, also known as dimeric alcohol or dimeric fatty alcohol. This can be easily produced by hydrogenation of the dimeric fatty acids. polyether polyols of the general formula (II) • They can be examples of the polyol component a), where Rl * is a hydrogen or a lower alkyl residue (for example Cx to CA or Ca. to Cl +), optionally with several subtenants, n is two at 6 and m is from 10 to 50 or even more, where the reslluoe Rl * are identical or different. The polyester polyols can be established as additional examples of the polyol component a). The polyester polyols can be produced, for example, by "Sterification of organic dicarboxylic acids or the anhydrides thereof with organic polyols. The dicarboxylic acids and polyols can be aliphatic, cycloaliphatic or aromatic dicarboxylic acids, and polyols. The dicarboxylic acids may be long chain dicarboxylic acids with 16 to 60 carbon atoms in the chain. The long chain component can be an alkylene or aralkylene chain or a chain with similar j * drof properties. A preferred long chain dicarboxylic acid is C3A dicarboxylic acid known as dimeric acid. The C3A dimeric fatty acid fractions consist substantially of a dimeric compound (CaA carboxylic acid di) with up to approximately 20 to 2% trimer compound (CBt +). Such mixtures are described as the dimeric fatty acid. A mixture with 97% dimer and 3% trimer is preferred. The polyesters preferably have a molecular weight of 300 to 6000, an OH value of 20 to 400 and a value of less than 3, preferably less than 1. Linear polyesters are preferably used. Polycarbonate diols, such as those described in EP-A-0 427 979, can also be used, for example, as component a). Polyester polyols, preferably diols, derived from lactones can also be used as component a). These products are, for example, obtained "by the reaction of a β-caprolactone with a diol Examples of such products are described in US-A-3, 169, 945. The polylactone polyols obtained by this reaction are distinguished by the presence of a terminal hydroxyl group and by components of repeating polyester derivatives from the lactone These repeating molecule constituents can, for example, be in the structure of the general formula. 0 -C- (CHRs) rl-CHa! 0- (iii) wherein n is preferably from 4 to 6 and the substituent R is hydrogen, an alkyl residue, a cycloalkyl residue or an alkoxy residue, wherein it contains no substituents of more than two carbon atoms and the total number of carbon atoms in the substituents of the lactone ring does not exceed 2. The lactone used as the starting material can be any desired lactone or any combination of lactones, wherein this lactone preferably contains at least 6 carbon atoms. carbon atoms in the ring, for example from 6 atoms to 6 carbon atoms and wherein at least two hydrogen substituents must be present on the carbon atom which is attached to the ring oxygen group. The lactone used as the starting material can be represented by the following general formula IVs - CH-, (CRB2) n - C = 0 (IV) where n and Rs have the meaning already established. The preferred lactones in the invention for the production of polyester diols are the E-caprolactones in which n has a value of 4. The most preferred lactone is the €-unsubstituted caprolactopa in which n has a value of 4 and all the RB substituents are hydrogens. This lactone is particularly preferred because it is available in large quantities and the resulting polylactone diols produce coatings with excellent properties. Other lactones can also be used individually or in combination. Examples of suitable aliphatic diols for the reaction with the lactone include ethylene glycol, 1,3-propanediol, 1,4-butanediol and / or dimethylolcyclohexane. The reactive isocyanate compound that is used as component a) can, for example, be 1.5 polyethers containing OH groups and / or SH groups such as condensation products of thiodiglycol with itself and / or with other glycols, dicarboxylic acids, hydroxycarboxylic acids, formaldehyde, aminocarboxylic acids, or aminoalcohols. The products are mixed polyether ether esters of mixed plotioether or ester polyether ester ester amides. Polyacetals containing OH groups prepared, for example, from the polyols mentioned above, in The specific polyacetals can also be obtained by polymerization of cyclic acetals, polyether esters containing polyether groups, and polyethylene glycols. reactive isocyanate, polyester and polyamide amides containing groups OH, which preferably include condensation products prepared neatly from polybasic and unsaturated saturated carboxylic acids or from the anhydrides thereof and to polyhydric, saturated and unsaturated indole alcohols, diamines, polyanes or mixtures thereof. Carbonates dihydro ipol iester. Polyurethane diols, which can be produced from either appropriate carbonates and diaminee or, as is conventional, from suitable polyols and polyisocyanates. Polymethacrylate polyols, in particular diols of f Mimetacrylate. Diols of polybutadiene oils. siloxane copolymers functionalized with hydroxy, such as for example copolymers of < x, w-dihydroxypolietet-polidi eti 1-si loxane. Emtas classes of compounds can be used alone or as mixtures of two or more of themselves. Compounds that correspond to two or more of those classes, (can be used * - * also intramolecular mixtures). Low molecular weight compounds which can also be optionally used in a) are in particular alcohols and amines. These are the compounds of a molecular weight below 600, preferably below 300, which have hydroxyl and / or amino groups and are at least difunctional with respect to the known isocyanate addition reaction from the chemistry of polyurethane. The compounds which can be considered as na are only compounds which are difunctional with respect to the addition reaction of the isocyanate but also at least trifunctional compounds or any desired mixtures of such compounds. Any desired organic polyisocyanates, such as, for example, diisocyanates, can be used as component b) for the production of the polyurethane dispersion. Aliphatic, cycloaliphatic or aromatic isocyanates may be used as well as estethically hindered isocyanates. polyisocyanates, for example diisocyanates, containing ether or ester groups, can also be used, for example. Examples of suitable diisocyanates are trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexadecyanate diisocyanate, propylene diisocyanate, ethylene diisocyanate, 2,3-dimethylethylene diisocyanate, 1-methytrimethyl diisocyanate, diiocyanate. of 1, 3-cyclobenzyl or 1,4-phenylane diisocyanate, 1,2-cyclohexyl diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-diisocyanate. -tol i loo, 2,6-tolyl ilena diisocyanate, 1, isocyanatom e 1 -5-oocyte nata-l, 3, 3-t ime i lcyclohexane, bis- (4-isocyanatocyclohe yl) met no, bis- ( 4-isocyanatophenyl) ethane, 4,4-di-isocyanatodiphenyl ether, di-diisocyanate of 1,5-dibutylpentamethyl, tetramethyl-xylene diisocyanate, 2,3-bie- (6-isocyanatoctyl) -4-oti 1- 5-hexyl ichlohene, ieocyanate Ae 3 (4) -ieacianata and 1-1-met il-cyclahexyl and / or 2,6-diisoci natometyl caproate. Isocyanates which are hindered and / or without yellow heat with 4 to 25, preferably 6 to 16 carbon atoms, containing 1 or more cyclic or linear alkyl groups, branched with 1 to 12, preferably 1 to 4 carbon atoms, in a position «in relation to the NCO group are those that are preferably used. The structure of origin may consist of an aromatic or alicyclic ring or of a linear or branched aliphatic carbon chain with 1 to 12 atoms of 16 *; rbono. Examples of such compounds are isofurone diisocyanate, bis- (4-isato-nato-cyclohexyl) methane, di-isocyanate of 1, 1,6,6-tetramethylhexylene ethylene, 1,5-dibutylpentane diisocyanate, oriocene. of 3 (4) -isacyanatomethyl 1-1-methylcyclohexyl, p- and m-tetramet-ilxy-li-lena diisocyanate and / or the corresponding hydrogenated homologs thereof. Small proportions of highly functional isocyanates, such as biuret or polyisocyanates The isocyanurate type, or products obtained by the reaction of an excess of diisocyanate with polyols, can also be added optionally. This approach, however, is not preferred. Compounds that can be used confocally with the invention as component c) are preferably low molecular weight compounds containing more than one, preferably 2 or at least 2 active iocyanate groups, and at least one ionic group, group capable of formation of ion and / or hydrophilic group. Apionic or anion-forming groups are preferred. Appropriate reactive isocyanate groups are in particular hydroxyl groups and primary and secondary amino groups. Acid groups capable of anion formation which can be considered are, for example, groups of carbaxyl acid, phosphoric acid and sulfonic acid. The basic groups which can be converted into cations which can be considered are, for example, primary, secondary and tertiary amino groups or groups of opium, such as quaternary ammonium, phosphonium and / or tertiary sulfonium groups. The anionic groups which are preferable to be introduced according to the invention are carboxyl groups; they can, for example, be introduced using hydroxyalkane carboxylic acids of the following general formula as component c): (HO) MQ (COOH) and wherein Q represents a linear or branched hydrocarbon residue with 1 to 12 carbon atoms and? and y means each of 1 to 3. Examples of such acids are citric acid and tartaric acid. Those carboxylic acids in which x = 2 and y = l are preferred. Examples of such acids are described in US-A-3, 41, 054. Lin preferred group of acids < * Hydroxyalkane comprises acids < x, a-dimet and the alkaline of the general formula CH20H Q'-C-COOH CHffl0H where it is hydrogen or alkylates from 1 to 6 carbon atoms. The most highly preferred compounds are < x, α-dimefc i lolpropiónico and acid a, a-dime i lolbut írica.

Additional examples of dihydroxyalkanoic acid which can be used are dihydroxipropionic acid, dimethylolokatic acid, dihydroisuccinic acid or hydroxybenzoic acid. The polyhydroxy acids obtained by the oxidation of onosaccharides, for example gluconic acid, saccharic acid, uic acid and glucuronic acid are also suitable. The usable acids containing amine groups > «-? N, for example, acid«, < x-diaminova.l. rich, 3,4-diaobenzoic acid, 2,4-diamino ~ (5 > -toluenesulfonic acid and 4,4-diamino-di f, or 1 sulphonic ether) Acid polyesters as described in DE-A-39 03 604 can also be used as component c) according to the invention. These polyethers preferably have a molecular weight of 300 to 2000, a hydroxyl value of 56 to 374 and an acid value of 8 8 to 167. Polyurethane polyols containing ionic groups or groups that are converted to ionic groups can also be used as component c > . Such a polyurethane polyol is obtained in the form of a prepolymer with OH end groups by, for example, the reaction of one or more polyisocyanates, such as those established for component b) with an excess of one or more compounds or was established for component a) and with at least one compound as established for component c).

Component c) may also include nonionic hydrophilic palols. These are, for example, compounds that have polyether chains with incorporated ethylene oxide units. These are compounds with 1 or 2 hydrogen atoms capable of reacting with isocyanates, the compounds of which have polyether chains with ethylene oxide, for example, in the side chain or mixtures thereof. These are, for example, compounds of the general formula R5 »R: a HO - CH - CH» - - CH »- CH - OH (V) NH - R - NH - CO - 0 X - Y - R < HO - X - Y - RA (VI) HNR: a - X - Y - RA (VID) in which . = the residue arises from an isacyanate component, for example from an isocyanate as stated above e te, R3 = H, alkyl of 1 to 6 carbon atoms straight or branched, RA = alkyl of the 12 atoms carbon, alkyl of 1 to 4 carbon atoms preferably unsubstituted, X = a residue as obtained by removal of the terminal oxygen atom from a polyalkylene oxide chain with 5 to 90, preferably 20 to 70 chain members .. wherein the chain members consist of up to at least 40%, preferably 65%, of ethylene oxide units and which, in addition to the ethylene oxide units, can for example also represent propylene oxide, butylene oxide or styrene oxide units. Of the aforementioned units, the propylene oxide units are preferred. Y = -O- or -NRA-, where RA is as defined earlier. Compounds V to VII can be produced, for example, "Analogous manner to US-A-3,920, 596, US-A-3,905,929, US-A-4,190,566 or US-A-4, 237, 264. The anionic, cationic or non-ionic groups of component c) act to stabilize the aqueous dispersion. The ionic and nonionic groups can be used together. Stabilization by ionic groups is preferred, particularly by anionic groups preferably. The dihydroxycarboxylic acids are preferred for the production of an anionic urethane prepolymer. Propionic dimethyloxy acid is particularly preferred. The component c) is preferably used in an amount of approximately 0.4 to approximately 7.5% by weight, particularly preferably from 0.6 to 5.0% by weight (calculated as carboxyl group, COOH), relative to the urethane prepolymer used ( solid resin). If the amount of the carboxyl groups is below approximately 0.4% by weight, it is difficult to produce a stable emulsion. On the other hand, if the amount exceeds 7.5% by weight, the hithophilic properties are not counted, making the emulsion highly viscous and reducing the water resistance of the coating. Therefore, the amounts of a), b) and c) are selected such that when they react, a reaction product with NCO terminal groups is made, ie an excess of polyisocyanate is used. The reaction can be performed with an NCO to OH ratio of 1 to 4: 1, the scale from 1.1 to 2: 1 is preferred, than that of 1.1 to 1.7: 1 Preferred polyurethanes are preferred to those having less than 260 milliequivalents of -NHC00-100 g of solid resin.The reaction product may have a branched structure, although a linear structure is generally preferred. of polyurethane containing NCO groups is reacted with one or more compounds of the general formula A '((HX-> r, R> ßSi (0R', t, (R ") 1_ (I) with X = 0 , S, NH or NR "", preferably between NH or NR'V, R = an organic residue diffuses to tetrafunctional, preferably difunctional with a molecular weight of 13 to 500, preferably (ar) alkyl with 12 carbon atoms, particularly alkylene with 1 to 1.2 carbon atoms preferably, i = alkyl of 1 to 6 carbon atoms or C (O) R '' ', preferably alkyl of 1 to 4 carbon atoms, R' '= R' '' = alkyl of 1 to 10 carbon atoms, R'v = alkyl from 1 to 6 carbon atoms a = 1, 2 or 3, preferably 1, b = 1, 2 or 3, preferably 2 or 3 c = 0 1 or 2, n = 1 to 3, preferably io 2, particularly preferable 1 ~ "* - in which the sum of a plus b plus c is four, optionally mixed with one or more alkanolamines possessing NH_¡, and NH and with a CH functionality of at least 1, to produce a prepoly was PU functionalized with R'OSi containing ionic groups, groups capable of ion formation and / or hydrophilic groups The compounds of the formula (I) are silane derivatives of the type (HX -) "R containing hydrogen groups, -? >and capable of addition with isocyanate groups. Amine groups are preferred as HX- functional groups containing hydrogen. n has a value of 1 to 3, n aeu and preferably the value of 1. The residue R is a difunctional to tetrafunctional, preferably di functional, organic residue which may possess chemically inert or substituent groups, having a molecular weight of 13. to 500. The residue R is preferable between a residue of (ar) alkyl or difunctional with 1 to 12 carbon atoms. An alkylene residue with 12 carbon atoms is particularly "" emitted as residue R. The silane derivative of the formula (I) contains in addition from 1 to 3, preferably 2 to 3, groups -OR 'attached to the silicone, in where R 'preferably has the meaning of an alkyl of 1 to 6 carbon atoms. Some preferred examples of the compound (I) which may be mentioned are β-aminoet i ltr ietioxisilana, t-ami npropi ltr i to isi laño, T-ami opropi ltr imeto iei ioño, T- * Fino ro i i i ld ito isilano , Ta inonrop i lfe i ldietax iei a, t-aminopropiltr imetoxisilano, á-aminobut iltr ietoxisi laño, < 5-ai obut ilet ildietox ieilana, N- (2-amincetil-3-ai opra il) tri e oxiei o, N-2-a inoe il-3-a ino ro i 1-t ie- (2-ethilexo i) yes l, 6- (aminohe ilami opro il) trimetDX i-si, na inoet il-3-aminopro i lmethyldi ethoxysilane. The reaction of the NC0-functional polybutane prepolymer to produce the pre-polymer R'OSi functionalized with * W proceeds with the HX groups of compound I being completely consumed. The isocyanate groups and the HX groups are preferably reacted in a methoxymetric manner together in a ratio of 1: 1. In other words, it is also possible to carry out the reaction with an excess of isocyanate groups. The remaining isocyanate groups can be used for additional synthesis reactions, for example by reaction with water, hydrazine, carboxylic acid hydraZides, palols to amines. The polyurethane resin on which the polyurethane dispersion according to the invention is based on hydroxyl groups. If so desired, the polyurethane prepolymer containing NCO groups is reacted during the production of the PU prepolymer functionalized with R'OSi with at least one compound of the general formula I and with at least one alkanola ina which has at least one NH group and / or NH and which has a functionality of at least 1. The reaction proceeds with the complete consumption of the HX groups of the compound ~ and the NH groups of the alkanolamine. The isocyanate groups of the functional PU prepolymer with NCO are preferably reacted in a stoichiometric ratio with the HX groups of I and the NH groups of the alkanolamine. In this reaction, the alkanolamine and the compound I can react with the functional polyurethane pre-mixed with NCO either mixed together or in succession. The alkanolamines of the groups Hg, and / or NH fi. E have a functionality of at least 1 are compounds which can act as sources of hydroxyl groups in the polyurethane resin dispersion according to the invention. The NH or NH.sub.i groups of the alkanolamines are considerably more reactive towards the isocyanate groups of the functional NCO prepolymer with NCO than those which are for the OH groups thereof, that is, the NH groups preferably react with the isocyanate groups to form urea. . Examples of suitable alkanolamines having an OH functionality of at least 1 are the monoalkanolamines and alkalolanes, for example diethanolamine, N-methyl-ethanolamine, di-isapropanole-ina, N-ethyl-1-oroprpanolamine, onoisoc propapolamine, ethanolamine, 2,2- amne or ethanol, monoethylethanolane, butylethanolamine, cyclohexylethanolane, 3-amino-ropanol, 2-amylo-1-butanal. Other monofunctional compounds reactive towards the NCO groups, for example monoanes and / or mannolalkols with alkyl residues of 6 to 30 carbon atoms can Also used instead of the alkanolanes possessing NH and / or NH groups. Fatty amines and / or fatty alcohols having more than 1.2 carbon atoms are particularly preferred here. In this case, the polyurethane resins with siloxane bonds that are obtained do not contain hydroxyl groups. The monoamines and / or monoalcohols can, of course, also be used in admixture with the alkanolamines possessing the NH and / or NH groups. The OH value of The resulting polyurethane resin with siloxane bonds can thus be adjusted at will within the scale according to the invention of 0 100. An essential characteristic of the invention in the production of the polyurethane resin, over which the dispersion of The polyurethane according to the invention is based, consists of an amount of water sufficient for the hydrolysis of the R'OSi groups that are added to the PU prepolymer functionalized with R'OSi, which optionally has hithyroxyl groups. The water is preferably added in excess of This is 10 times the amount of water needed to hydrolyze the R'OSi groups. From 1 to 5 times of the stoichiometric amount of water is preferably added. The hydrolysis reaction, together with the accompanying chain extension, may if desired be performed at an elevated temperature. Temperatures up to 95 ° C are, for example, appropriate. The silane groups formed by hydrolysis are dense to form siloxane bonds, which leads to the desired increase in the molecular weight that arises from the chain extension, depending on the PU-prtfpol, it is worked with R'OSi which is used. , linear, entangled or branched products are obtained that virtually do not contain R'OSi and / or HOSi groups The formation of siloxane bonds proceeds in the phase of resin disperea or non-diepersa, that is before or after the conversion in the dispersion * Auosa The polyurethane resin has ionic groups, groups capable of ion formation and / or hydrophilic groups. If the polyurethane resin contains groups capable of ion formation, these are partially or completely converted into the corresponding salts with an appropriate compound, a neutralizing agent. This may occur at any stage of the synthesis described above, where care must be taken to ensure that the compounds used for salt formation are selected such that they are chemically inert, in the presence of the substance. The compounds used for salt formation, such as, for example, the neutralization agents, are preferably added together with the water necessary for the hydrolysis. Preferred ion formation groups are those that are capable of anion formation. The vertical axis of the groups are described above for the synthesis of the PU prepolymer containing the NCO groups. A bath, by an amine, preferably a tertiary amine, is then used for the conversion into anions. Suitable tertiary amines are, for example, trialkyl lamines, such as t-ethyleneamide, t-ethylamine, tri-isopropyl-lane, tri-n-pr-p-lamine and t-i-n-but-i-lam; N-alkylmorpholines, such as N-met i lorum folin and N-e i lmor fol ina; N-dialkyllalkallamines, such as N-dimethylethanolamine, N-diethyl ethanolane and N-dimethexopropanolamipa and mixtures of at least two of these. "If the polyurethane resin contains cation formation groups, preferably use one or more acids for the formation of ion Suitable acids are, for example, phosphoric acid or acid phosphoric acid esters, or organic carboxylic acids such as formic acid, acetic acid, propionic acid, acrylic acid, hydroxycarboxylic acids such as lactic acid, dimethylolpropionic acid, or citric acid, or bicarboxylic acids such as alonic acid, glutaric acid or oxalic acid.

The mixtures of the acids can also be used.A quaternization reaction with alkylating agents, such as for example the reaction with alkyl halides or epoxides, is also possible.The reaction of the components used to synthesize the functional PU prepolymer with NCO and the additional reaction to produce the PU prenalimer f inalized with R'OSi proceed in an anhydrous environment; for example at temperatures of 20 to 140 ° C, preferably between 50 and 100 ° C. The reactions can be run without solvents or in organic solvents suitable for the synthesis of the polyurethane which are known to those skilled in the art. Solvents that are iscible or immiscible in water can be used as solvents. In general, it is advantageous to use those solvents which can be removed at any stage of the production of the PU dispersion according to the invention, for example after the termination thereof), for example by distillation, optionally under reduced pressure. . Examples of suitable sanitizers are ketones, for example acetone, methyl ethyl ketone, methylisobutyl ketone, N-alkyl-pyrrolidone, such as, for example, N-me i 1-pyrrolidone; ethers, such as, for example, diethylene glycol dimethyl ether, di-propyl di-glycol di-ethyl ether, or cyclic urea derivatives, such as, for example, 1,3-dirnethyl-3,4,5,6-te rahydro-2 (IHApirimidi ona.

The polyurethane resin that is free of solvent or in an inorganic solution is converted to the aqueous phase by adding sufficient amounts of water. The sufficient amount of water for conversion into the aqueous phase can be added after the conclusion of the chain extension. This is also possible to add the main quantity of water during the chain extension or after the swelling of the R'OSi groups. A dispersion of finely divided Polyvintane is obtained with an average particle size of more than 10 and less than 2000 mm preferably greater than 50 and less than 500 mm. The distribution here can be monamodal or bimodal, preferably monamoda.L. It is generally not necessary to use emulsifier to convert the polyurethane resins used according to the invention to aqueous dispersions. However, this does not exclude the addition of ionic emulsifiers and ionic 0 * 0 in order to facilitate emulsification and to reduce the number of ionizabl.es groups. The adducts are reacted together during the production of the polyurethane dispersion according to the invention in such amounts as the qualities of the binder desired by the person skilled in the art, such as, for example, dispersibility in water, viscosity, film formation characteristics, storage stability, are obtained. The properties, such as for example the hardness and weathering resistance, of the coatings obtained from the dispersions can also be influenced by the selection of the nature and quantity of the components. The persons skilled in the art can easily select the nature and quantity of the components using the teachings referred to herein, optionally combined with routine tests. Generally, the amounts of individual educts are selected "Rectifiably and the controlled reaction such that the polyurethane resin on which the polyurethane dispersion according to the invention is based contains 2 to 150 mmol of siloxane bonds (- Si-O-Si-) per 100 g of solid resin, a number average molecular weight (Mn) of 2500 to 1000000, a hydroxy number of 0 to 100, preferably 0 to 60 mg KOH / g, relative to the solid resin, and a content of ionic groups, groups convertible into ionic groups and / or hydrophobic Zones of 5 to 200 mEq per 100 g of the solid resin.The aqueous PU dispersion of the extended chain resin by the formation of Siloxane bonds can be produced using known procedures, for example, it is possible to initially introduce the neutralized resins and combine them with the water with all the dispersion. optionally containing the neutralizing agent and to incorporate the resin by stirring. A continuous method is also possible, ie the resin, the water and the neutralizing agent are homogeneously mixed in known units, for example a rotor / stator mixer. The conversion to the aqueous phase can also be induced by elevated temperature. The pH value of the resulting polyurethane dispersion can, for example, be adjusted to a value between and 10. A milky cloudy aqueous dispersion is obtained Paca, finely divided from the components. The anionic PU dispersions according to the invention or preferably used according to the invention have an acid value of 5 to 90 (relative to the solid) preferably of more than 10 and below 50. The content of solids is between 25 and 50. and 65% by weight, preferably more than 35 and ores of 60% by weight. The average molecular weight number (Mn) of the polyurethane resins contained in the PU dispersions according to the invention or used according to the invention is for example, 2500 to 1000000, wherein the lower limit is preferably 5000, particularly preferable 20,000, and the upper limit is up to 500000. Any solvents normally contained in the polyurethane dispersion in accordance with the invention may, if desired, be removed by distillation. . This can proceed under reduced pressure. The present invention also provides aqueous coating compositions, preferably water-based plates, which can be produced from the dispersions PU according to the invention containing siloxane bonds. Aqueous coating compositions can be self-drying (physical drying) or extrinsic entanglement. The PU resins on which the PU dispersions according to the invention are based have hydroxyl values of between 0 and 100, preferably between 0 and 60 mg "OH / g.If the PU dispersions according to the invention are used in compositions of extrinsic entanglement coating, the hydroxyl value is preferably towards the upper end of the titration scale In order to produce aqueous coating compositions preferably water based lacquers, pigments, additional binders, additivity together with small quantities of solvents are, for example, aggregates to the PU dispersions The coating compositions according to the invention may contain one or more additional binders in addition to the polyurethane resin dispersion according to the invention This may, for example, be favorable in order to obtain synergistic effects Examples of additional binders are soluble resins in ag ua for film formation or conventional water-dilutable resins for those skilled in the art, such as water-dilutable lime resins, water-dilutable polyacrylate resins and / or different water-dilutable polyurethane resins. The resins can be reactive or non-functional. The amount of added resins can be 0 to 75% by weight, preferably 0 to 50% by weight of the total content of resin solids. 0 to 30%, are particularly preferred. In this regard, the total resin elastids means the sum of all the binders without the content of entanglement agent. The specification and quantity of additional binders are selected so that a rubric is obtained? preferably to have an average content of ionic groups, groups convertible to ionic groups and / or hydrophilic groups of 5 to 200 mEq per 100 g of solid resin. Anionic groups are preferred. The aggregate binders can optionally be - ** <recondensed at elevated temperatures with polyurethane resins defined according to the invention. The usable water-dilutable polyesters are, for example, those with free carbaxyl groups, ie polyesters with a high acid value. There are essentially two known methods for incorporating the necessary carboxyl groups in the resin seventh. The first method is to terminate the iodization at a desired acid value. In this method, the incocpation of sterically hindered carboxyl groups is preferred, for example by condensation with dimethylated propionic acid. Once neutralized with baeee, the polyesters obtained in this way are soluble in water. The second approach consists in the formation of partial esters of di- or polycarboxylic acids with higher hydroxyl polyesters with a low acid value. The anhydrides of dicarboxylic acids are conventionally used for this reason, whose anhydrides are reacted with the hydroxyl component under moderate conditions to form a free arboxylate group. The water-dilutable polyacrylate resins that can be used, as well as the polyester resins described above, can contain free carboxyl groups. These are, for example, copolymer acrylic or methacrylic and the carboxyl groups originated from the content of acrylic or metaclic acid. Examples of additional polyurethane specifications are those described in DE-A-36 26 125. Fstae are anionically stabilized PU dispersions which can be obtained by reacting polyol. Diisocyanates, ionic compounds together with the chain extension with amines The PU dispersions stabilized by hydro ionic ionic groups can also be added to the coating compositions according to the invention. The water-dilutable polyurethane or water-resilient resins can be excised or grafted by suitable dispersion polymerization processes. Examples of usable acrylated polyurethane di persions are described in DE-A-41 22 265. A further group of aqueous dispersions that can be added to the coating compositions according to the invention are dispersions described in DE-A-36. 26 124 based on ionic polycondensation products containing epoxide groups that are reacted with unsaturated or polycarbonate manomers. When additional binders are added, it is self-evident that the ionically stabilized resins and dispersions can only be used with dispersions Ionics loaded in an identical manner in accordance with the invention, in order not to have a negative influence on the stability Several entangling agents can be used to prepare the coating compositions in accordance In the invention, such as, for example, condensation condensation resins, such as phenol condensation resins / aldehyde form and amine / formaldehyde condensation resins, together with blocked polyisocyanates. used individually or as combinations The mixing ratio of the crosslinking agent of the polyurethane resin is preferably 10:90 to 40:60, particularly preferably 20:60 to 30:70, in each case relative to the weight of the solids If additional binders are used in addition to the 36 * Dispersion of polyurethane resin according to the invention, the above mixed mixing ratios preferably refer to the contents of complete resin solids. Suitable amine resins as crosslinking agents include, for example, alkylated condensation products produced by reactive aminotriacs and amidatiakines with aldehydes. The amines or compounds possessing amino groups such as melamine, tuanamine, acetoguana ina, benzoguanamine, dicyanase or urea are condensed with aldehydes, in particular formaldehyde, in the presence of alcohols such as methanol, ethanol, propanol, butanol or hexanol. The reactivity of the amine resins is determined by the degree of condensation, the ratio of the amine or amide components to focmaldehyde and by the nature of the ether alcohol used. Examples of such resins and the production thereof are described in '' Jjtouben-Weyl, Methoden dec Acganischen Chemie, 1963, page 357. These are common commercial products. The blocked polyisocyanates can also be used as crosslinking agents. Any desired polyisocyanates, in which the isocyanates have been bound to react with a compound in such a way that the resulting blocked polyisocyanate is resistant to hydroxyl groups and water at room temperature, but reacts at elevated temperatures such as for example in the scale of Approximately 90 to approximately 250 ° C can be • used in the invention. Any suitable organic polyisocyanate desired for entanglement can be used to produce the blocked polyisocyanates. Preferred polyisocyanates are those which contain approximately 3 to about 36, in particular of about 6 to about 15 carbon atoms. Examples of suitable diisocyanates are the diisocyanates stated above as component b). The polyisocyanates of relatively high isocyanate functionality, as stated in b) above, are preferably used. Examples of these substances are tr is- (4-isaciantropheni 1) -methane, 1,3,5-tri-isocyanatobenzene, 2,4,6-triisocyanato-toluene, 1,3,5-r is- (6- ieacia atahexane) biure, bis- (2, 5-diisoci-nato-4-methylfe-1) methane and polymeric polyisocyanates, such co-dimers and trimers of diisocyanatotoluepo. Mixtures of isocyanates can also be used. The organic polyisocyanates which can be considered as crosslinking agents in the fluffiness compositions with the invention can also be prepolymers, for example derivatives from a polyol. For this purpose, the polyols are reacted in a conventional manner with an excess of polyisocyanates, thus producing prepayners with isocyanate end groups. The blocked polyisocyanates that can be used according to the invention as entanglement agents can be blocked with conventional volatile monovalent blocking agents, as used in lacquer chemistry. Examples of such substances are various alcohols, oximes, phenols, NH-functional nitrogen heterocycles, such as pyrazole derivatives or triasol derivatives, amines, β-keto compounds and phthalic compounds. The polyisocyanates can be blocked within A single molecule with different or different blocking agents The differently blocked polyisocyanate mixtures as well as the polyisocyanates which are blocked differently intramolecularly can also be used as blocking agents. The invention may also contain polymeric microparticles known to those skilled in the art.The interlaced or non-interlaced microparticles may be exemplified Examples of such polymeric microparticles are described in EP-AO 036 127 and EP-AO 234 362 The coating compositions may contain lacquer additives, eg, agents that include the rheological properties, such as highly dispersed silica, inorganic phyllosilicates or polymeric urea compounds. Water-soluble cellulose ethers, such as hydroxyethylcellulase, me-cellulose or carboxymethylcellulose, together with synthetic polymers and / or groups with an associative action such as polyvinyl alcohol, polyether-amylamide, an alimethacrylate, polyvinylpyrrolidone, styrene-anhydride maleic or two ethylene-allylic anhydride copolymers and derivatives thereof or hydrophobically modified ethoxylated polyurethanes or polyethyls also act as thickeners. Anti-fuming agents, leveling agents, light stabilizers, anti-foaming agents, such as, for example, silicone-containing compounds; Wetting agents together with coupling substances can also be isolated. Wetting agents are also taken to include known paste resins that can be used to improve pigment dispersion and grinding. The catalysts can optionally be used to accelerate the cure, although it is also possible to cure with thermal energy without using a catalyst. Suitable solvents present in small amounts are conventional lacquer solvents, which can Examples of such solvents are mannitol or polyhydric alcohols, for example propanol, butanal, hexanol, glycol ethers or ethers, for example diallyl ethers of diethylene glycol, and can be added separately. dialkyl ethers of dipro-ethylene glycol, in each case with alkyl of 1 to 6 carbon atoms, eta-ipropanol, monobutyl ether of ethylene glycol, glycols, for example, and glycol, propylene glycol and the oligomers thereof, N-methyl-1-pyrrolidone together with ketones such as met i let ilketones, acetone, c iclohexanone; < aromatic or aliphatic aromatics, for example, toluene, xylene or linear or branched aliphatic hydrocarbons of 6 to 12 carbon atoms. The flow and viscosity of the reverse composition may be influenced by the selection of the solvents. The instantaneous vaporization behavior can be influenced by the boiling point of the Solvent mixture used. The coating compositions according to the invention may contain one or more organic and / or inorganic effect pigments and / or colorants and optionally an additionally a grower. Examples of effect pigments are metallic pigments, for example made of aluminum, copper or other metals; the interference pigments, such as for example The metal gums are coated with metallic oxides, for example aluminum coated with titanium dioxide, coated micas, such as, for example, titanium dioxide-coated micas and graphite-effect pigments, examples of coloring pigments and extensionists. They are the titanium dioxide, the titanium dioxide micronized, iron oxide pigments, carbon black, silicon dioxide, barium sulfate, mycorrhized mica, talc, kaolin, clay, azo pigments, phthalocyamine pigments, quinacridone pigments, pyrropyrrole pigments, perylene pigments.

The effect pigments are initially introduced in the form of a conventional commercial aqueous or non-aqueous paste, optionally combined with organic solvents preferably dilutable in water and additives and then mixed with the binder with shear. The pulverulent effect pigments can first be converted to a paste with organic pigments preferably dilutable with water and additives. Care should be taken to ensure that the pigments are not mechanically damaged during mixing. Colored pigments and / or spreaders can, for example, be ground in a proportion of the aqueous binder. The milling can also be carried out in a special water-dilutable paste resin. An example of a paste resin based on the preferably usable polyurethane is the water-based lacquer according to the invention can be found -? * DE-A-40 00 669. The grinding can be carried out in conventional family units for people experienced in the technique. The preparation of the finished ground color pigment is then formulated with the remainder of the aqueous binder or the aqueous paste resin. If the paste resins are present in the coating composition, these are added to the binders plus any entanglement agents optionally present when the solid content of reein is calculated.

If the aqueous lacquer according to the invention is formulated on the basis of the preferred anionically stabilized PU dispersion of chain extended with siloxane bonds, it contains bases as the neutralizing agent. Examples are ammonia or organic amines such as triethylamine, N-met il orfolin, aminoalcohols such as dimethylisopanole ina, dime i letapola ina, 2-amino-2-me i 1-1-propapol. The coating compositions according to the invention are preferably formulated with water-based lacquers, as used in multi-coat lacquer coatings and overflows with clear and transparent lacquers. Such a water-based lacquer has a solids content of, for example, 10 to 50% by weight, for basecoats giving effect is preferable from 15 to 30% by weight, for lacquers with simple color is preferable higher, for example 20 to 45% by weight. The pigment to binder ratio optionally plus the crosslinking agent optionally plus the resin paste in the water based lacquer is, for example, between 0.03: 1 to 3: 1, for effect base lacquers, is, for example, preferred 0.06: 1 to 0.6: 1, for bake lacquers of simple and preferably higher color, for example 0.06: 1 to 2.5: 1, in each case in relation to the pee of the solids. The solvent content of the water-based lacquer according to the invention is preferably below 20% by weight, particularly below 15% by weight, in particular below 10% by weight, preferably. The water-based lacquers according to the invention can be applied using conventional methods. They are preferably applied by asperioning to a dry film thickness of 6 to 50 μm for effect basecoats and the dry film thickness ee, for example, preferably 10 to 25um for single-colored basecoat is preferably t. ayor, for example 10 to 40? m. The application is preferably carried out wet, it will taste wet, ie, after a period of instantaneous vaporization, for example at 20-60 ° C, layers of water-based coatings are overcoated with a conventional clear lacquer to a dry film thickness. preferably from 30 to 60 μm and is or is entangled together with the latter at temperatures of, for example, 20 to 140 ° C. The drying conditions for the topcoat lacquer layer (basecoat and clearcoat) are determined by the / * clear lacquer system used. They can be for example between to 150 ° C, for repair supplies, the temperatures of to 60 ° C, are, for example, preferred. For the purpose of reversing original lacquers, temperatures above 100 ° C for example at 110 ° C are preferred. Suitable clear lacquers are in principle any known clear lacquers or transparent pigment coating compositions. It is possible to use one or two component lacquers that contain solvents, clear lacquers on a water bath, powder coatings or lacquers curable by radiation for this purpose. The reverse coatings of multilayer lacquers produced in this way can be applied to the most varied types of substrates. In general, the substrates are made of metal or plastics. These are often prerevigated, that is to say, plastic substrates can, for example, be provided with a plastic apresta, metal substrates generally have an electroformingly applied sizing and One or more layers of optional lacquers are selected, such as, for example, these layers are generally fully cured. The aqueous bake lacquer according to the invention can, however, be applied wet on wet on non-interlaced surface forming layers, as described for example in EP-AO 236 037. In this case, the base lacquer is generally heated with the surface focmadac layer before the application of a coating layer Aperior of clear lacquer. It is also possible to apply the water-based layer according to the invention directly, without additional interlayers, on a layer of non-heated or heated electro-coating, as is also possible for other water-based or solvent-based lacquers known. The coating compositions according to the invention are excellently suitable for coating varnishes of other substrates, in particular organic substrates, such as concrete, wood and for sheeting (plastic films and sheets of paper) and for the production of Thin layers to join two or more substrates together. The coating compositions formulated with the polyurethane resin dispersions according to the invention are distinguished by good storage stability. The dispersion is directly dilutable with water; There is little requirement for coelectors. The The coating ions formulated in accordance with the invention exhibit excellent atomization behavior when applied by spraying. Very good adhesion between layers is obtained when multiple layer structures are produced. The good metallic effects are obtained when formulating metallic lacquers, even if the polyurethane dispersion according to the invention is used as the only binder in water-based lacquers. The multilayer lacquer coatings obtained with aqueous based lacquers according to the invention meet the current conventional automotive lacquer requirements. The water-based lacquers according to the invention are suitable for automotive priming coatings and automotive coatings, although they may also be used in other sectors, for example lacquer coating plastics, particularly for automotive lacquer coating components. This invention also relates to a substrate 46 ^? dressed with a multi-layer coating obtained by applying at least one size coat, preferably based on a coating composition carried by the waters, by applying a layer of colored lacquer with a coating composition of conformity with the invention, optionally by drying the undercoat layer and applying a transparent coating composition as the topcoat layer and subsequently heating the coated Aubstcato. Additional layers can optionally be added to this multilayer lacquer coating. In the coating of multilayer lacquers according to the invention has a good surface. The adhesion between the layers and the basecoat layer is good and, even when exposed to humid climate, it does not exhibit any inaccuracy. This invention is particularly suitable for application in automotive lacquer coating (original lacquer coating and repair). Multilayer lacquer coatings produced using the aqueous basecoat lacquers according to the invention containing dispersions of expanded PU with silaxane bonds as the binder are distinguished by outstanding resistance to exposure to condensed water. Aqueous basecoats containing expanded PU chain dispersions with siloxane bonds. "The only binder is suitable for the production of multi-layer coating with improved development in comparison with the coatings of varnish. corresponding effecta that can be produced using aqueous effect base lacquers containing PU dispersions of the prior art as the sole binder.

EXAMPLE OF PRODUCTION 1 339 g of a polyester prepared from adipic acid, hexanediol and isophthalic acid (OH value 104) and 19 g of dimethyl lalprapionic acid were dissolved in 160 g of pyrrolidone and heated to 40 ° C. Then 5 g of isofurone diisacyanate was added in such a way that the reaction temperature of 60 g was not exceeded. The reaction temperature was maintained until an NCO content of 2% (with respect to the solid resin) determined for DIN 53 165 was attained. 14.6 g of 3- to n-propyltriethoxy-ylane and 16.2 g of diethanolamine were added in succession. The reaction mixture was kept at 60 ° C until more free NCO groups were detected. Neutralization was achieved by adding and fully incorporating a mixture of 2.6 g of triethylamine and 12.6 g of deionized water. Once 563.4 g of completely deionized water was grown, a dispersed aqueous polyurethane was finally divided.

"Characteristics: Solids 30 '150 ° C: 40.1 Acid value, solids: 15.9 mEq to ina / 100 g of solid resin: 26.1 pH value: 7.6 Average particle size: 69 nm EXAMPLE OF PRODUCTION 2 339 g of a polyester prepared from adipic acid, hexanediol and isophthalic acid (OH value 104) and 19 g of dimethyl acid were dissolved in 160 g of N-methyl pyrrolidone and heated to 40 ° C. Then, 15 g of iaafuran diisacyanate was added in such a way that the reaction temperature did not exceed 60 ° C. The reaction temperature was maintained until an NCO content of 2% was reached (with ^ "Elation to Solid Resin) determined for DIN 53 165. 43.6 g of 3-aminoo-pyrrolysy not and 2. 3 g of dietnala ina. The reaction mixture was maintained at 60 ° C until no more free NCO groups were detected (titration). The neutralization was achieved by adding and completely incorporating a mixture of 12.6 g of triethylamine and 12.6 g of deionized water. Once 163.4 g of completely deionized water had been added, a finely divided aqueous polyurethane dispersion was obtained. .l, Solid Characteristics 30 '150 ° C: 39.6 Acid value, solids: 16.0 mEq to ina / 100 g of solid resin: 25.4 pH value: 7.6 Average particle size: 101 nm EXAMPLE OF PRODUCTION 3: 339 g of a polyester prepared from adipic acid, hexanediol and isophthalic acid (OH value 104) and 19 g of dimethylolipathionic acid were dissolved in 160 g of N-ylpyrrolidone and heated to 40 ° C. they then added 125 g of isafurone diisocyanate in such a way that the reaction temperature did not exceed 60 ° C. The reaction temperature was maintained until an NCO content of ^ ~ (in relation to solid resin) determined for DIN 53 165. Then, 42 g of 3- were added to the inoculum and to the islet. The reaction mixture was maintained at 60 ° C until no more free NCO groups could be detected (titration). Neutralization was achieved by adding and completely encapsulating a mixture of 12.6 g of triethylamine and 12.6 g of deionized water. Once 563.4 g of fully deionized water had been added, a finely divided aqueous dispersion was obtained.

^ Characteristics Solids 30 '150 ° C: 40.4 Acid value, solids: 16.2 mEq amine / 100 g dés solid resin: 26.5 Valoc pH: 7.2 average particle size: 73 nm EXAMPLE OF PRODUCTION 4 339 g of a polyester prepared from adipic acid, hexanediol and isophthalic acid (OH value 104) and 19 g of dimethylolpropionol acid were dissolved in 160 g of N-met i pyrrolidone and heated to 40 ° C. Then 116.3 g of trime ilhexa and i-diisocyanate were added in such a way that the reaction temperature would be 60 ° C. The reaction temperature was maintained until an NCO content of • *% (relative to the solid resin) determined for DIN 53 165 was reached. Then 33.6 g of 3- aminopropylmethyliethoxyß and 4.6 g were added in succession. of diethanolamine. The reaction mixture was maintained at 60 ° until no more free NCO groups could be detected (titration). The neutralization was achieved by adding and completely incorporating a mixture of 10.9 g of N, N-dime and lysopropanole ina and 10.9 g of deionized water. Once 565.1 g of completely deionized water were added at 60 ° C, a dispersion of finely divided aqueous urea-urethane was obtained.

Characteristics Solids 30 '150 ° C: 39.6 Acid value, solids: 16.5 Fq amine / 100 solid resin: 24.9 pH value: 6.0 Average particle size: 124 nm EXAMPLE OF PRODUCTION 5 339 g of a palyster prepared from adipic acid, hexanediol and isophthalic acid (OH value 104) and 19 g of ionic dimethylolpro acid were dissolved in 160 g of N-met ilpyrrolidane and heated to 40 ° C. Then 125 g of isofurone diieocyanate was added in such a way that the temperature The reaction did not exceed 60 ° C. The temperature was maintained until an NCO content of 2% (relative to the solid resin) determined for DIN 53 165 was attained. 35.4 g of 3-amine-co-ildime-iletoxysilane were then added. The reaction mixture was kept at 60 ° C until no more free NCO groups could be detected (itching). Neutralization was achieved by adding and incorporating a mixture of 14.5 g of triethylamine and 14.5 g of deionized water. Once 561.5 g of fully deionized water had been added, a finely divided aqueous dispersion was obtained: Characteristics: Solids 30 '150 ° C: 40.3 Acid value, solids: 16.4 Fq amine / 100 solid resin: 26.6 pH value: 6.4 Average particle size: 62 nm EXAMPLE OF PRODUCTION 6 346 g of a polycaprolactan diol (OH value: 102) and 19 g of dimethyl or propionic acid were dissolved in 160 g of N-methylpyrrolidone and heated to 40 ° C. Then 136 g of 1,3-bis (1-isacyanate-1-methyl-1-i-benzene (TMXDI) were added so that the temperature of the reaction of 100 ° C) exceeded. The temperature was maintained until it reached an NCO content of 2% (relative to the solid resin) determined for DIN 53 165. Then, 43.6 g of 3-aminapropi ltriethoxysilane and 2.3 g of diethanolane were added in succession. The reaction mixture was maintained at 60 ° C until no more free NCO groups could be detected (itching). Neutralization was achieved by adding and incorporating a mixture of 12.6 g of triethylamine and 12.6 g of deionized water. Once 609.4 g of fully metered water had been added, a dispersion of slurried aqueous slurry finally divided was obtained: Characteristics: Solids 30 '150 ° C: 39.6 Acid value, solids: 15.2 niFq amine / 100 solid resin: 23.4 pH value: 7.1 Average particle size: 11.2 nm EXAMPLE OF PRODUCTION 7 a) production of a functional polymer with carboxy containing epoxide groups: For 1 hour 100 g per crawling an anhydride mixture (acid value / Ha0 = 466) produced by the reaction of trimethyl ion with 1,2-propanediol was added, Consisting in this way of trimethyl anhydride and anhydrides = 6 which had been homogenized in 106 g of ileal at 50 ° C were added to a solution of 141 of a polyester (OH value = 66), produced on the basis of phthalic anhydride, isophthalic acid, maleic anhydride and glycerol as described in DE-OS 26 11 913 in 70 g of met i let i lcetona. The mixture was stirred at 90 ° C, which the reaction mixture had reached an acid value in the water of 15 (100% reein). 12 g of water were then mixed, and after 6 hours of stirring at 60 to 90 ° C, an acid value in butanol of 166 (100% resin) was obtained. The temperature of the mixture was reduced to 60 ° and, once 0.3 g of lithium benzoate had been added, 132 g of an epoxidized linseed oil (epoxide value = 6.7) were added dropwise for 2 hours and the mixture it was stirred until the acid value in butanol fell to 66.5. A mixture of 42 g of dimethylamine (60% in water) in 660 g of water was stirred , 'then. A clear yellow opalescent solution was obtained, from which the organic solvent was removed by distillation at 0.1 bar and 40 ° C. After filtration, a virtual yellowish clear aqueous resin solution was obtained. Solids content: 32% (1 hour at 1.25 ° C). b) production of the polymer dispersion 705 g of the above aqueous dispersion (32%) and 196 g of water were placed in a reactor equipped with a stirrer, reflux condensate, internal thermometer and feeding device for the monomers and initiator. This mixture was stirred at 60 ° C while it was stirred and a solution of 0.5 g of peroxydisulfide d-ammonium in 35 g of water was added. 5 minutes after the addition of the initiator, 35 g of a mixture of mon? Echo prepared from 125 g of methyl methacrylate, 94 g of n-butyl acrylate and 17 g of glycidyl methacrylate were added and after an additional 15 minutes of prepolymerization, the remaining amount of monomer was distributed for 2 hours. 10 minutes after the completion of the addition, an additional 0.2 g of ammonium pepsin diphosphate dissolved in 10 g of water was added for 10 minutes and the bath was stirred for an additional 2 hours at 60 ° C in order to ensure complete conversion. A stable aqueous dispersion with a solids content of about 40% was obtained.

EXAMPLE OF PRODUCTION & a) production of a functional polymer with carboxy containing epoxide groups: 100 g of anhydrous mixture (acid value / Ha0 = 560) produced by the reaction of tri-ethyl anhydride with i, 2-propanediol, which had been ogenized in 30 g of acetones at 50 ° C, were added dropwise for 1 hour to a solution of 127 g of a polyester (OH value = 107) in 70 g of methyl ethyl ketone. The mixture was stirred at 90 ° C until the reaction mixture had reached an acidic value in the water of 197 56 ícon relation to 100% resin). Then 15 g of additional water were mixed. After 6 stirring flats of 60 to 90 ° C, the acid value in butanol was 160 (100% resin). The temperature of the mixture was reduced to 60 ° C and 133 g of an epoxied linseed oil (epo value = 6.9) was added dropwise over two hours. The mixture was stirred until the acid value in the butanol decreased to 90. A mixture of 56g was then stirred. ^ e dimet i laminoetanal in 540g of water. A yellow opalescent solution was obtained, from which the organic solvent was removed by distillation at 0.1 bar and 40 ° c. After filtration, a virtually clear yellowish aqueous resin solution was obtained. Solids content (1 h at 125 ° C) approximately 39%. b) Production of the polymer dispersion 355g of the aqueous dispersion (39%) was mixed < At the end of the experiment, with 452g of water in a reactor equipped with a stirrer, reflux condenser, internal thermometer and feeding devices for the monomers and the initiator, the mixture was heated to 60 ° C while it was being stirred and stirred. A solution of 0.5 g of ammonium idisulfate in 35 g of water was added, 5 minutes after the addition of the initiator, 35 g of a monomer mixture prepared from? 165 g of methyl acrylate, 142 g of n- was added. butyl acrylate and 24 g of hydro? ethylacr ylate, after 15 additional minutes of pre-polymerization, the remaining amount of; ffhpnomers distributed during 2 hours. 10 minutes after the completion of the addition, an additional 0.2g of ammonium peroxydisulfate dissolved in iOg of water was added for 10 minutes and the bath was stirred for an additional 2 hours at 60 ° C in order to ensure complete conversion. The stable aqueous dispersion having a solids content of about 40% was obtained.

EXAMPLE OF PRODUCTION 9 Production of a paste resin In a reaction vessel with an internal thermometer and reflux condenser, 1395 g of a linear saturated polymer (synthesized from adipic acid and esterperopentyl glycalic acid hydroxypivalic acid) were thoroughly stirred with an OH value of 1.12 and a viscosity (a A * ^: 0C of 6.7 Pa-s with 161g of dimethyl-lalpropionic acid and 163g rimetil propane and ee dissolved with heating up 90 ° C and then cooled to 50 ° C. Once 665 g of tetramethyloxy isocyanate had been added, the mixture was heated slowly to 120 ° C until the NCO content was below 0.2%. The mixture was then diluted with 661 g of meto ipropanol.

Solids content (30 min. 150 ° C) 75%.

Acid value (relative to solids) 27 Viscosity at 25 ° C, diluted with methoxypropanol at 40 210 mP-s * A mixture prepared from 56.3g of dimethetanolamine and 56.3g of water was quickly added to 1963g of this resin solution and sa heated to 60 ° C. Mix Then it was diluted with water to produce a highly viscous turbid paste that could be easily worked when heated with the following characteristics: Content of solids (30 min 150 ° C) 32.3 P.% Viscosity at 25 ° C 1.3 Pa-s * value mEq 41 pH value 7.6 * measured in a rotary viscometer with a coaxial cylinder arrangement for DIN 52 016 and 53 019 after 5 minutes of shear stress at a gravity of shear of 231 sec-.

HOMATION OF THE COMPONENTS FOR THE FOLLOWING EXAMPLES OF LACQUER EXAMPLE OF PRODUCTION 10 Production of a binder solution 50.00 g of the water-based binder described above in example 7 is mixed with + 3.94 g of fully deionized water and 6.00 g of butoxyethanol and ee adjusted to a pH value of 6.2-6.4 with 0.06 g of N-dimeti laminoethanol.

EXAMPLE OF PRODUCTION 11 Production of an aluminum paste composition ^ .50 g of a conventional aluminum paste with a metal content of 65% was thoroughly stirred with a mixture of 7.00g of butoxyethanol and 15.50g of fully deionized water and then combined with a mixture prepared from 4.00g. of the binder described above in the production example 7 and additionally 4.50 g of the binder described in the production example 2, 10OOg of butoxyethanol, 34.70g of deionized com pound water, and 3.00 g of a commercially available acidic thickener thickened. The pH value was adjusted to 6.2-6.4 with a mixture prepared from 0.06g of N-dimethylamine-ethanal and 0.72g of completely deionized water.

EXAMPLE OF PRODUCTION 12 Production of a ground blue pigment preparation Using a solvent of 100 g of Cu-f talocyanine pigment, 14.00 g of a conventional hexametoxylamine resin and 10 000 g of butoxyethanal were added and, after adding an additional S.OO g of a melamine resin and 10 000 g of butane ethanol, completely dispersed with a ribbon mill. This was prepared with a mixture prepared from 0.90 g of a conventional commercial acidic acrylate thickener and 16.91 g of fully deionized water and adjusted to a pH of 7.1-7.3 with 2.00 g of N-dimethylaminoethanal and 26.19 g of water. completely deionized.

EXAMPLE OF PRODUCTION 13 Production of a ground green pigment preparation 20.00g of a chlorinated phthalacyanine pigment is prepared with a solvent in a mixture prepared from 20.00g of the binder described above in Production Example 9, 35.0g of butoxyethanal and 0.50g of N-dimethylatoethenoethanol and are dispersed in a ribbon mill. The mixture is then diluted with 24.50 g of completely deionized water.

EXAMPLE OF PRODUCTION 14 The same method described in the production example 10 was used, although the binder described in the production example 6 (50.00g) was used.

EXAMPLE OF PRODUCTION 15 The same method described in the production example 11 was used, but using the binder described in the production example 2 (4.50g).

Examples of lacquer formulations EXAMPLE 1 1. 1 Production of a metal based lacquer based on water, blue. 30.00 g of the binder solution described in the example of production i n 10 are stirred for a period of 30 min. with 19.00g of the aluminum paste composition described in the production example 11, 1.90g of acidic acrylate thickener (as previously used), 17.44g of fully deionized water and 0.25g of N-dimethoxyethanol. 25.50 g The polyurethane dispersion described in the production example 6 was stirred into that mixture and an amount of 0.94 g of the ground pigment preparation described in the production example 12 was added. 4.00g of n-butanol was then stirred and the viscosity was adjusted to 90-95 mPa.s at a shear force gradient of 100 sec- * with 0.96g of water. Solids content: 16.0 in weight (120 minutes in a circulating air bag at 1.20 ° C). 1. 2 Application of the base lacquer and clear lacquer. The base coat described in 1.12 is sprayed with an air-atomizing gun onto a metal sheet pretreated in a conventional manner by means of zinc foaming, electrocoating lacquer and spraying sizing so as to achieve a total dry film thickness of 15 .mu.m in two coatings. The conditions during the application of the basecoat are an ambient temperature of 23 ° C and a relative humidity of 60%. After application, the coated sheet is quickly dried for 5 min at 50 ° C in a circulating air oven and, once it is cooled to 23 ° C, it is overcoated in a conventional manner with a clear resin lacquer. conventional commercial ica / elamina and heated during 30min at 130 ° C. A coating free of uniform turbidity is obtained with excellent metallic effect, high gloss and outstanding resistance to the de-condensed water.

EXAMPLE 2 2. 1 Production of a metal-based water-based lacquer, silver-colored. In a manner similar to Example 1.1, a silver-colored bake lacquer is produced from 40.00 g of the binder solution described in the production example 14, 19.00 g of the aluminum paste composition described in the production example 15, 1.90 g of acid acrylate thickener, 0.26 g of N-dimethylaminoethanol, 22.00 g of polyurethane dispersion (according to production example 2), 4.00 g of n-butanal and 1.2. £ 4g of fully deionized water. The solids content is 16.0 by weight (120 minutes in a circulating air oven at 120 ° C). The viscosity is 90-95 mPa-s at a shear stress gradient of 100 sec ~ 2. 2 Application of the basecoat and a clear lacquer. As described in Example 1.2, a pretreated sheet of metal is coated with the basecoat and rapidly dried for 5 minutes at 50 ° C. After cooling, the faith * amine is overcoated with a clear lacquer of conventional commercial two-component / isocyanate and heated for 30 minutes at 130 ° C. The coating obtained in this way is distinguished by a high gloss, an absolutely uniform cloud formation effect, a pronounced metallic effect and an outstanding resistance to condensed water.

EXAMPLE 3 3. 1. Production of a water-based, green base metal lacquer. The basecoat is produced in a manner similar to Example 1.1 from 59.00g of the binder solution in accordance with the production axis 10. 16.50g of the composition of aluminum paste in accordance with production example 1.90g of acid acrylate thickener, 0.26g of N-dime and laminoethanal, 4.60g of polyurethane dispersion of con fi rm with the production example 4 0.60g of the preparation of green ground pigment described in the production example 13, 4.00g of n-but nal and 10.94g of completely de-ionized water.

Solid content: 17.1% by weight (120 minutes in a circulating air oven at 1.20 ° C), Viscosity: 90-95 mPa.s at a shear gradient of 100 sec_A 3. 2 Application of the basecoat and a clear lacquer As described in example 1.2, the lacquer of bake 66 From 3.1 on a pre-treated metal sheet and, after rapid removal, a conventional commercial acrylic / melamine clear lacquer is overcoated and heated for 30 minutes at 130 ° C. The green metallic coating is obtained with an equally good range of properties as in examples 1.2 and 2.2.

EXAMPLE 4 4. 1. Production of a base lacquer of red color uni form. 300g of a conventional paste resin (according to DE-OS 4 000 669) was mixed with 350g of a conventional commercial tubing pigment (Calour Index network 166). The pH is adjusted to 6.5 with dimeti-letanolamine and the solids content up to 50% by weight by adding ionized water. The mixture is completely dispersed in a ribbon mill until it is transparent. 4.2. 1.4 g of a thickedac based on conventional polyacrylic acid (solids content: 10% by weight, pH 7.5) were mixed with 129 g of the dispersion from example 1 and 40 g of the paste resin of example 4.1. Then 24g of a conventional commercial water-insoluble melamine resin (Setamine US 13 / BB 70 from Akza) were then added to 10 g of the red paste of Example 4.1. and stirred Homogeneously. An application viscosity of 100-130 mPa.s, determined by rotary viscosity at a shear rate of 231 sec-1 and 25 ° C, was then established with deionized water. 4.3. Application of base lacquer and a clear lacquer The acrylic lacquer obtained is sprayed on the conventional phosphated work body sheet already provided with a cathodic electrocoat and a surface coating. The coating is applied to a dry film thickness of 30um. After the application, the coating is vaporized for 10 minutes at room temperature and then pre-heated for 10 minutes at 60 ° C. An original automotive clear lacquer for curing with melamine resin based on acrylic resin is then overcoated to a dry film thickness of 35 m and dried for 16 minutes at 120 ° C (object temperature). A multi-layered lacquer coating with outstanding resistance to condensed water (DIN 50 017, 240 hours, 40 ° C) is obtained.

EXAMPLE 5 Production of a 20g silver-plated two-lacquer metallic lacquer coating of a conventional commercial aluminum paste suitable for plates of 65% by weight aqueous bau and aluminum is mixed with 20 g of ethylene glycol nomobutyl ether, 6 g of N- methylpyrrolidopa and lg of a commercial conventional wetting agent to produce a bronze brewing paste. Then 1.4 g of a thickener is mixed based on conventional commercial polyacrylic acid (contained in eolides: 10% in peeo, pH 7.5). 129g of the dispersion from Example 1 and 40g of the paste resin from Example 4 are stirred in the bronze colored solution. 24 g of a commercially available water-insoluble melamine resin (Setamine US 136 / BB 70 from Akzo) are also stirred. An application viscosity of 100-1.30 mPa-s, determined by rotary viscosity at a shear rate of 231 sec- and 25 ° C, is then established with deionized water. The aqueous basecoat is sprayed on the conventional phosphatized work body sheet already provided with up-cathode-coating and surface-forming coating. The coating is applied to a dry film thickness of 15u. After application, the reverse is reheated for 10 minutes at room temperature and then pre-dried for 10 minutes at 60 ° C. An original automotive clear lacquer for curing with melamine, commercial and conventional resin based on the acrylate resin is overcoated to a dry film thickness of 35jm and dried for 16 minutes at 120 ° C (target temperature). A multilayer lacquer coating is obtained with an absolutely uniform haze-free effect formation, a pronounced metallic effect and outstanding resistance to water condemned.

Claims (7)

NOVELTY OF THE INVENTION CLAIMS

1. - Aqueous dispersion of one to more polyurethane resins with an average molecular weight number (Mn) of 2500 to 1000 000, a content of 2 to 150 mmol of siloxane bonds (-Si-O-Si-) per lOOg of resin solid, a tidro ila dß value 0 to 100 and a content of ionic groups, groups that are converted into ionic groups and / or hydrophilic groups of 5 to 200 mFq per lOOg of solid resin.

2. The aqueous dispersion according to claim 1, further characterized in that a polyurethane prepolymer containing ionic groups, groups capable of ion formation and / or hydrophobic groups, can be obtained by dß chain extension. the prepolymer has at least one R'OSi- group, in which R '= C to C? alkyl or C (0) R '"and R'" = Ci-C -.o alkyl, which may be present in the presence of an organic solvent, by adding at least one water stearic amount to hydrolyze the SiOR 'groups and convert the reaction product neutralized in an aqueous dispersion with the addition of water during or after the chain extension and optionally removing any solvent present by distillation.

3. Process for the production of aqueous dispersions of polyurethane resins, characterized in that a polyurethane prepolymer contains ionic groups, groups capable of ion formation and / or halophyllous groups, in which the pre-mixer has at least one rump R 'OSi-, in which R '.. Ci to C? alkyl or C (0) R '"and R"' = Ca.-C or alkyl, and which may be present in the presence of an organic solvent, is subjected to chain extension by adding at least a stoic amount of water ether to hydrolyze the SiOR 'groups, convert the reaction product during or after the chain extension. After the complete partial to neutralization in an aqueous dispersion, optionally removing any solvent present by distillation, wherein the proportions of the individual educts are selected in such a way that the finished polyurethane resins contain from 2 to 150 mmol of siloxane bonds (-Si-O-Si) per lOOg of solid resin, have a number average molecular weight (Mn) of 2500 to 1000 000, a hydroxyl value of 0 to 100 mg KOH / g relative to the solid resin and a content of ionic groups, groups convertible to ionic groups and / or hydrophilic groups is 5 200 mFq per lOOg of solid resin.

4. The process according to claim 3, characterized in that the functional polyurethane pre-isocyanate and degeli fi ed, linear or branched polyurethane containing ionic groups, groups capable of forming ion and / or hydrophobic groups prepared in a organic solvent or in the absence of organic solvents is reacted with one or more compounds of the general formula ((H-X -) "R) < -, Yes (0R ') b (R ") ß (I) with X = 0, S, NH or NR'V, R = a difunctional, tridifunctional or tretrafunctional organic residue with a molecular weight of 13 to 500, R '= alkyl laughs C to C? or C (0) R '' ', = R' '' = alkyl of Cj. a Cxo, R'v = alkyl of C ± a C ?, a = 1, 2 or 3, b = 1, 2 or 3, c = 1 to 3, wherein two to more residues R ', R "and R"' can be identical or different and in which the sum of a plus b plus c equals 4, optionally mixed with one or more alkanoamines possessing groups NHa and / or NH and with an OH functionality of at least _. , to produce a polyurethane prepolymer functionalized with R'OSi- wherein the chain exteneion proceeds upon the addition of the water, the optionally neutralized reaction product ee converts to an aqueous dispersion with the addition of water during or after extension in chain and optionally any solvent present is removed by distillation.

5. The process according to claim 4, further characterized in that the functional polyurethane with isacyanate is produced by the reaction in an anhydrous environment of a) at least one linear or branched compound, which at least has isocyanate-reactive groups with an average molecular weight of 60 to 10000, b) at least one organic polyisocyanate and c) at least one compound with more than one isocyanate-reactive group and therefore less an ionic group, a group capable of forming the ion and / or hydrophilic group with an average molecular weight number (Mn) of up to 10000, preferably up to 2000, in an NC0 / 0H ratio above 1 to 4: 1.

6. The method of affinity with claim 5, characterized in that the component a) a linear or branched compound used is at least one polyol based on one or more polyethers, polyesters, and / or polycarbonates having at least 2 rumps OH per molecule and an average molecule number (Mn) of 600 to 10000, rationally together with one or more alcohols of molecular weight less difunctional.es and / or amines and / or aminoalcohols with a molecular weight of less than 600 7.- Aqueous coating composition containing a dispersion of aqueous polyurethane resin according to claim 2 or obtainable according to one of claims 3 to 6, optionally with one or more solvents and / or lacquer additives. conventional 6. The coating composition according to claim 7, which contains one or more aldehyde condensation resins and / or blocked polyisocyanates as entanglement agents. 9. The coating composition according to claim 7 or 6 which additionally contains one or more additional binders in an amount of up to 50% by weight, based on the sum of the solids content by weight of all the agglutinating agents. and the agents of. ntrelazamienta. 10. Use of the dispersion of the aqueous polyurethane resin according to claim 1 or 2 or obtained in accordance with one of claims 3 to 6 in aqueous coating compositions. 11. The use of the aqueous coating compositions according to one of claims 7 to 9, or basecoats in multi-layer coatings. 12. The use of the aqueous coating compositions according to one of claims 7 to 9 for the coating of original lacquer and repair of industrial articles and motor vehicles and the components thereof. 76 AQUEOUS DISPERSION OF POLYURETHANES CONTAINING SILOXAN LINKS. PRODUCTION OF THE SAME AND USE IN COATING COMPOSITIONS SUMMARY OF THE INVENTION The aqueous dispersion of one or more polyurethane resins having an average molecular weight number of (Mn) from 2500 to 1000 000, a content of 2 to 150 mmol of siloxane bonds (-Si-O-Si-) per lOOg of solid resin, a hryroxyl value from 0 to 100 and a content of ionic groups, groups which are converted into ionic groups and / or hydrafine groups from 5 to 200 Fq per lOOg of solid resin and the process for the production thereof by chain extension of a polyurethane prepolymer containing ionic groups, groups capable of forming ions and / or hydrophilic groups which have at least one R'OSi- group in which R '= C ± a Cß alkyl or C (0) R "' and R" '= CA a Cxo alkyl by adding water. The aqueous dispersion is suitable for aqueous coating compositions which are suitable in particular for multilayer lacquer coatings. RML / cg #c m * mvß * ieoh *