DE1282962B - Process for the production of aqueous sedimenting, redispersible dispersions of crosslinked polyadducts containing urea groups - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. a .;

C08g

C 09 d; D06m;
C14c

German class: 39 b5- 41/00

51/44; 22 g -3; 22 $ 3;
8k-1 ^ 8 a-9

Number: 1282962

File number: P 12 82 962.8-43 (F49039J

Filing date: April 28, 1966

Opening day: November 14, 1968

It is known to convert polyurethanes with ionic groups in the molecule into aqueous dispersions. According to Belgian patent specification 653 223, ionic polyurethanes can be made from organic polyisocyanates and compounds having at least two reactive hydrogen atoms with the additional use of Compounds which apart from at least one NCO group or at least one reactive hydrogen atom contain at least one salt-like group or group capable of salt formation will. According to a preferred embodiment, this is used to produce a dispersion Process of the solution of such a structured ionic polyurethane in a suitable organic Solvent and replace it with »5 water.

When building up the polyurethane, a distinction is made according to the ratio of the isocyanate groups to the reactive hydrogen atoms three possibilities: ao

1. NCO groups in deficit,

2. equivalence,

3. NCO groups in excess.

When converting to an aqueous dispersion, no further chemical substances occur in cases 1 and 2 Reactions with the water. A maximum chain length is only possible in case 2. But only predominantly there high molecular weight polyurethanes with a linear structure are sufficiently soluble in organic solvents, this maximum chain length can only be achieved if crosslinking reactions are largely eliminated. The latex particles according to 1 and 2 are e.g. B. soluble in dimethylformamide.

The situation is different in case 3. The excess NCO groups react with water below Chain elongation and branching of the molecules, and the latex particles can be converted into dimethylformamide be largely insoluble. This process has some serious drawbacks and most of the time it leads to clumping of approaches. The main disadvantage is that a primarily formed latex changes greatly with time. For example, an initially thin, finely divided latex can take a few hours or only after a few hours Days to clump together completely or turn into a quark-like state. Another disadvantage is that you need relatively large amounts of water to make a latex at all Very poor reproducibility.

It was therefore to be expected that the production of aqueous polyurethane dispersions would require a high process for the production of aqueous polyurethane dispersions
sedimenting redispersible dispersions crosslinked, containing urea groups
Polyaddition products

Applicant:

Paint factories Bayer Aktiengesellschaft,
5090 Leverkusen

Named as inventor:

Dr. Harro Witt, 5000 Cologne-Buchheim;

Dr. Dieter Dieterich, 5090 Leverkusen

cross-linked, discrete particles made of ionic polyurethanes or polyureas with free NCO groups not realized by simple means in a reaction step in a technically useful manner could be because on the one hand the pre-adducts are still soluble in organic solvents and therefore would have to have a largely linear structure and, on the other hand, the reaction of the excess isocyanate groups causes great difficulties with water.

The invention relates to the production of aqueous sedimenting, redispersible dispersions crosslinked polyadducts containing urea groups from NCO-polyurethanes and Polyamides, which is characterized in that polyurethanes and / or polyureas with ionic Groups and with free NCO groups in the presence of polyamines with more than two primary and / or secondary amino groups and / or hydrazine with water in any order or mixed at the same time by simply bringing them together.

According to a preferred embodiment of the process according to the invention, the Solutions of the ionic polyisocyanate addition product containing NCO groups in a suitable one organic solvents such as acetone, ethyl acetate, methyl ethyl ketone, tetrahydrofuran, benzene or methylene chloride or mixtures thereof, on the one hand and the polyamine or hydrazine in water on the other hand with stirring and removed the organic solvent by distillation, leaving a dispersion of highly cross-linked particles. Higher-boiling solvents such as cyclohexanone, chlorobenzene, Dimethylformamide or dimethyl sulfoxide,

809 637/1128

3 4

can be used if the dispersions - The surprising technical progress according to the invention not to be free of organic solvents is also that the preparation of the need; Aqueous dispersions of highly crosslinked urea It is known that amines react much more quickly with group-containing polyadducts with isocyanates than water. It was therefore in 5 simple means surprising in a .Reaktionsschritt in techhöchsten extent that can be realized with as quickly Nian very easily, reacting amines dispersing without encryption while proceeding according to the process of German Patentklumpung, you can even _daß less water writing 1 097 678 the reaction mixture is more vigorously required than otherwise with a dispersion and that it has to be carried out, with a high-performance stirring dispersion proceeding very well reproducibly. The io device, e.g. B. a high-speed stirrer has to be used, is particularly surprising when you get along with amines according to the invention with completely normal with more than two primary and / or secondary stirring devices. In this way, aqueous amino groups can be used, as is the case in the process according to the invention to prepare dispersions of crosslinked polyadducts. The decisive advantage which such dispersions is not produced, even in hot dimethylformamide that they dissolve more 15.

their final properties immediately after their production. The properties of those produced according to the invention and subsequently in the course of the dispersions can practically no longer be changed within wide limits over time. Another advantage is to vary suitable measures in a targeted manner. This applies in front of part of the process is that you do not have to worry about the hardness and size of the particles. Fast stirrer is instructed, but with normal, w The first possibility of influencing is in the low-speed stirrer gets by. Aqueous dispersions which are adducts can be prepared in this way by building up the ionic ion containing isocyanate groups. According to known methods, this does not dissolve even in hot dimethylformamide. (Belgian patent 653 223) using

The starting point listed in this patent specification is already known from German patent 1097 678, aqueous dispersions of polyurethanes 25 materials, so that at this point it is possible to dispense with a renewed enumeration based on higher molecular organic compounds. In addition, with at least two active hydrogen atoms as higher molecular weight substances with reactive atoms and excess organic diisocyanate-capable hydrogen atoms, amino groups with chain extension of the iso-containing compounds produced in this way can also be used, as they are in the cyanate group-containing pre-adducts with water 30 French patents 1,361,810 and 1,300,981, or a difunctional diamine. In · - the German Auslegeschrift 1,122 254 and der-USA.-In contrast to the invention, according to the polyurethanes patent specification 2,888,439 are described, and / or polyureas with ionic groups and The size of the particles is determined by the with free NCO groups in Presence of poly content of the pre-adduct of ionic groups whose amines with more than. two primary and / or secondary hardness 35 are mainly mixed by the type of polyisocyanates dary amino groups and / or hydrazine * with water and the compounds containing reactive hydrogen by simply contacting influenced atoms. If, according to this patent specification, one limits oneself to use such isocyanate- these compounds with median molecular weights group-containing pre-adducts which are free of up to about 500, harder products, verionic groups, are obtained. Thus, it is according applies the encryption 40 is relatively high molecular weight only to about driving of the cited German patent also "10000, we obtain softer. Between these mandatory erf orderlich, for the preparation of this aqueous extremes all mixing ratios are concomitantly possible. Dispersions emulsifier, wherein In contrast, it is carried out in solvents with, relatively according to the invention, without additional auxiliaries, 45 large excesses of isocyanate - the molar veraiso without additional emulsifiers, aqueous dispersion ratio of the NCO groups to the reactive ones Sions of crosslinked polyadducts from hydrogen atoms is expediently between 4 and 0, the dispersions thus obtained sedimentation, preferably from 3 to 1.4, being worked, but being redispersible at any time possible The ability to grow 50 containing crosslinked urea groups is a strict linearity of the chain structure of polyurethanes without the use of emulsifying agents; unnecessary. Technical solvents can be used to produce agents, - represents an essential area - which still contain water, can be used, the technology used for the ionic, NCO-group-containing poly-

"The process of the German patent 1097678 isocyanate adducts (polyurethanes and / or polyurines also require chain extension with 55 substances) are carried out according to methods known per se water" or difunctional diamines in the presence (Belgian patent 653 223) in an aqueous of alkali additives. This entrained dispersion is transferred, whereby according to the invention the addition of alkali is disadvantageous insofar as the dispersion is carried out in the presence of polyamines or the alkali is also hydrazines present in the finished dispersion. The polyamine is that must have a pH of 9. The hydro- 60 'are useful in the lysenstabilität for dispersing the polyurethanes by loading needed water is dissolved or dispersed. Sensitively reduced in knowledge. In business cases, the polyamine can also be dissolved in an organic solvent different from the method of the cited patent specification, while the polyamines or alloy are added during the dispersion according to the invention. "In this case, hydrazine is used as a reaction component with the iso- ^; 65 trap Appropriately concentrated solutions of the polycyanate component are reacted so that the highly crosslinked polyurea poly- "is readily soluble in a solvent" in which it is readily soluble as a dispersant. Solvents are except those which urethanes no longer show an alkaline reaction . are suitable for the isocyanate pre-adduct., low-

5 6

boiling alcohols, such as methanol or ethanol, or whether the organic in the aqueous or the aqueous

useful. is added to the organic phase. However, it is

In principle, all organic polyamines come as polyamines - again emphasized that one can use simple means

see connections in question, which more than two achieve the goal by e.g. B. with stirring

carry primary and / or secondary amino groups. 5 a normal stirrer the aqueous phase in the

Amino compounds which can also be incorporated as organic compounds are suitable. After or during the

Hardeners have been suggested for polyepoxides. Mixing is optionally the organic

Aromatic mononuclear or polynuclear solvents may be mentioned removed by distillation.

Polyamines, e.g. B. 2,4,4'-triaminodiphenyl, 1,2,4- or the dispersions produced according to the invention

1,2,3-triaminobenzene or 2,4,5-triaminotoluene, all-io-contained particles can be spherical or

Phatic polyamines, such as basic reaction products, are elongated in shape.

which have arisen by reacting aliphatic polyamines. Depending on their properties, such dispersions with polyhalogen compounds or polyhalogenhy- sions, also in combination with crosslinking agents, are produced, hydrogenated addition products, additives, various fields of application, e. Solidifying unsaturated nitriles such as acrylonitrile, ether amines or lamination - as of aliphatic polyamines or ammonia on 15 textile and leather equipment, coatings, Vliesa, /?. They can be used as binding or thioether amines, which are used in the hydrogenation of agents or as auxiliaries in the paper industry, cyanoethylated polyols or polymercaptans. The coarser dispersions are, ethyleneimine polymerization products, can be converted into powder by filtration, the finer, for example, addition products of ethyleneimine to poly- 20 by roller drying. B. and formaldehyde with aliphatic polyamines, that of the heat seal adhesive.
Hydrogenated condensation products of acetoacetic ester The dispersion can in any case be made with primary polyamines or basic polyamides without the addition of emulsifiers. Of course, aliphatic polyamines and polycarboxylic acids or 25 is possible, however, the dispersions additionally by their .Estern or lactams or basic poly subsequent addition of emulsifiers to Koaguharnstoffe. lation, caused for example by electrolytes, Furthermore, products should be mentioned, which stabilize from polyalkyl. In such cases, preference is given to vinyl ketones, polymethacrolein or ethylene-carbon nonionic stabilizers. Likewise, the use is monoxide copolymer by reductive amination 30 of protective colloids for such cases possible
or by hydrogenation of the corresponding oximes or

Hydrazones or Hydrogenation Example 1

products, from polyacrylonitrile to polymethacrylonitrile or ^ production of the starting material

Copolymers, the molecular weights below * ^bb

Should be 1000. 35,500 g of one dehydrated at 15 Torr and 130 ° C

Water-soluble aliphatic polyhexanediol - neopentyl glycol - adipic acid - polyester are preferred

amines with more than two primary and / or secondary (molar ratio of the diols 11: 6) with an OH number

the amino groups. The following compounds are of 67 with 107.6 g of hexamethylene-1,6-diiso-

for the process according to the invention especially cyanate about 2 hours at temperatures between

suitable: diethylenetriamine, triethylenetetramine, tetra 40 110 and 120 ° C stirred. It is allowed to cool to 50 ° C,

ethylene pentamine, pentaethylene hexamine, tripropylene sets at a bath temperature of 60 ° C 4 g of N-methyl

1,2-tetramine or bis (3-aminopropyl) amine. In addition to diethanolamine, dissolved in 20 ml of acetone, add, stir

Hydrazine are also substituted hydrazines, another 2 hours and diluted with 100 ml of acetone.

e.g. methylhydrazine, ethylhydrazine or phenyl- The acetone used in all examples contains

hydrazine. 45 0.22 to 0.25 per cent water. Then add 3.12 ml

The amount of polyamine depends on the NCO content of dimethyl sulfate and is stirred for 30 minutes at one of the polyisocyanate adducts (polyurethane and / or bath temperature of 60 ° C. The solution is several polyureas). The ratio of amino groups is stable for days. Is expediently in a range dispersion prior to transfer into the aqueous to NCO groups is diluted with a further 680 ml of acetone, of about 0.1 to 1.8, preferably from 0.2 to 1.5, 50 For the following preparations dispersion is to achieve highly crosslinked, in each case one fifth of the amount of the pre-insoluble particles obtained in dimethylformamide. The amino compounds can be used adduct solution,
can be used partly in the form of their salts. _ "", .._ _{TT J} "

The properties of the dispersions can be determined ^{according to the} invention
except by the chemical composition of the 55 water dispersion
Polyisocyanate pre-adduct is decisive due to the a) To 248 g of the pre-adduct solution, the dispersion conditions are allowed to be influenced in a targeted manner. Room temperature 140 ml of water in which 0.6 g of di- The most important factors are: the type and amount of ethylenetriamine dissolved in about a minute under polyamines, the amount of water, type and amount of stirring. At a bath temperature of 60 ° C. organic solvent, the pH value and 60 , the acetone is stripped off under reduced pressure. Reaction temperatures, which can be from about 0 ° C. to about 20 to 30 μ, which can also be carried out under pressure, which settle out but are easily redispersible , can be. b) The procedure described under a), except that the • Much is also the procedure of the 65 addition of the aqueous amine solution is not at room-mixing of the aqueous and organic phases, temperature, but at a bath temperature of whether this practically simultaneously, for example Made in a 60 ° C. The acetone is distilled off, continuously operating mixing device, taking it for the properties of the dispersions

is indifferent whether the distillation is carried out at 60 ⁰ C bath temperature under reduced pressure or at 70 to IOO ⁰ C under atmospheric pressure. A dispersion is obtained with particles which are on average 20 to 3.0 μm larger than those described above and which are insoluble in dimethylformamide.

c) The dispersion takes place as under a) and b), only the addition of the aqueous amine solution is under Cooling made with an ice bath. The resulting dispersion is different from the above described only by the particles that are on average 10 to 20 μ smaller than a).

C comparison test

The experiment is carried out according to B, a) with the difference that the 140 ml water is not Diethylenetriamine is added. The approach completely clumps when the acetone is distilled off.

Example 2. ^2p

. B. The proportions are the same as in Example 1 under B, a). The only difference in the preparation of the dispersion is that one does not add the aqueous phase to the organic one, but rather the «5 solution. of the pre-adduct in the aqueous solution of the triamine _t A normal stirrer is used. The result is a dispersion of about 5 μ of particles insoluble in dimethylformamide, but which can settle out easily.

C. Comparative experiment

* The experiment is carried out according to Example 2 B with the difference that the water has no Triamine is added. The approach clumps when the acetone is distilled off.

and dissolved in 1600 ml of acetone; For Examples 4 to 10, one tenth of the amount is used in each case.

B. Preparation of the dispersion according to the invention

To 249 g of the solution of the ionic polyurethane, which is stirred at a bath temperature of 60 ° C., leaves the solution of 1.4 g of diethylenetriamine in 240 ml of water is added dropwise in about ten minutes. To Evaporation of the acetone under reduced pressure gives an approximately 36% strength aqueous dispersion of Polyurethane urea particles of about 5 to 20 microns that are insoluble in dimethylformamide. The particles settle, but can still be easily removed even after months, e.g. B. by shaking, redisperse.

If the diethylenetriamine solution is adjusted to pH 7 by adding 1η-acetic acid, so a similar dispersion with particles of about 2 to 12 μ is obtained by the above process. .

Example 5

The procedure is as in Example 4, except that 1.49 g of triethylenetetramine are used in place of the diethylenetriamine. This results in an approximately 36 ° / ₀ aqueous dispersion of dimethylformamide in un *-soluble particles that are smaller than 10 μ, allowed to settle, but which can easily redispersible.

Example 6

Instead of the diethylenetriamine in Example 4, 1.62 g of tetraethylene pentamine are used. The result animal dispersion corresponds to that of example 5;

Example 7

In Example 4, the triamifl is replaced by 1.64 g of pentaethylene hexamine and a dispersion of Particles of the order of 50 μ.

Examples

Instead of the triamine in Example 4, 1.91 g of tripropylene-4,2-tetramine are used. The resulting Dispersion largely corresponds to that of Examples 5 and 6.

Example 9

The diethylenetriamine in Example 4 is replaced by 1.78 g of bis (3-aminopropyl) amine and one is obtained Dispersion of fibrous particles that can already be seen with the naked eye, which are contained in dimethylformamide are insoluble.

Example 10

Instead of the diethylenetriamine in Example 4, a basic amide with an equivalent weight of 114 is used, which is prepared from adipic acid and excess diethylenetriamine by known processes. If 2.28 g of the amide ₃ is used, a dispersion of about 20 to 100 μm particles is obtained; if 13.7 g is used, particles of the order of magnitude of up to 1 mm are obtained.

45

50

Example

A. Manufacture of the starting material

As in Example 1, 500 g of hexanediol * neopentylglycol adipic acid polyester (OH number 67), 4 g of N-methyldiethanolamine and 114.3 g of hexamethylene-1,6-diisocyanate produced an adduct with 3.12 ml Quaternized dimethyl sulfate and dissolved in 700 ml of acetone.

B. Preparation of the dispersion according to the invention

The solution is left to half of the starting solution at a bath temperature of 60 ° C. while stirring of 2.8 g of diethylenetriamine in 450 ml of water flow in about one minute. After removing the acetone an approximately 44% strength aqueous dispersion of particles insoluble in dimethylformamide of approximately 10 to 15 μ, which combine to form larger agglomerates. She settles down, but can be shaken easily redisperse.

B is ρ i el 4

A. Manufacture of the starting material

for Examples 4 to 11, Example 11

As in the example, an adduct of 1000 g hexane is used in place of the polyamines in Examples 4 to 9, diol neopentyl glycol adipic acid polyester (OH number 65 , 2.6 g of a 25% hydrazine solution are used. 63), 8 g of N-methyl diethanolamine and 208 g of hexa-es the result is an aqueous dispersion of particles of methylene-1,6-diisocyanate with 6.24 ml of dimethyl-less than 10 μ, which are insoluble in dimethylformamide and 1,6-diisocyanate, quaternized with 6.24 ml of dimethyl sulfate, are thus crosslinked.

C. Comparative experiment

The procedure is as in Examples 4 to 11, except that no polyamine is added to the water. The approach clumps together when the acetone is distilled off.

Example 12

A. Preparation of the starting material

An adduct of 500 g of hexanediol-neopentylglycol-adipic acid polyester (OH number 63), 3 g of N-methyl diethanolamine and 102.8 g of hexamethylene 1,6-diisocyanate are quaternized with 2.34 ml of dimethyl sulfate and dissolved in 800 ml of acetone.

15th

B. Preparation of the dispersion according to the invention

One fifth of the pre-adduct solution is stirred at a bath temperature of 60 ° C. and a solution of 1.6 g of pentaethylene ao hexamine in 250 ml of water is added in about 10 minutes. After the acetone has been distilled off under reduced pressure, an aqueous dispersion of particles which are insoluble in dimethylformamide and which settle but can easily be redispersed is obtained. The particle size is in a range as from 30 to 65 μ.

Example 13
A. Making the finishing materials

a) From 500 g of hexanediol neopentyl glycol adipic acid polyester (OH number 63), 2 g of N-methyl diethanolamine and 101.2 g of hexamethylene-1,6-diisocyanate, an adduct is prepared as usual ^ with 1.56 ml of dimethyl sulfate quaternized and dissolved in 800 ml of acetone.

35

B. Preparation of the dispersions according to the invention

One fifth of the amount of starting materials a) are each in one. Bath temperature of 60 ° C with stirring in about 10 minutes with a solution of 1.4 g of diethylenetriamine in 240 ml of water. The acetone is then distilled off under reduced pressure, and about 35% strength aqueous dispersions of 20 to 80μ particles which are insoluble in dimethylformamide and which settle but can easily be redispersed are obtained. ^1st

Example 14

A. Preparation of starting material _g0

500 g of hexanediol neopentyl glycol adipic acid polyester (OH number 67), 5 g neopentyl glycol and 147 g hexamethylene 1,6-diisocyanate are stirred at 110 to 120 ° C. _{for IV a hours.} It is cooled to 50 ° C, 8 g of 1,4-butanediol and 4 g of N-methyldiethanolamine in 40 ml of acetone are added and stirred for 4 hours at a bath temperature of 60 ⁰ C. It is diluted with 100 ml of acetone and quaternized with 3.12 ml of dimethyl sulfate. Before dispersing, it is diluted with a further 660 ml of acetone.

B. Preparation of the dispersion according to the invention

The solution of 1.03 g of diethylenetriamine is added to one fifth of the adduct solution with stirring flow in. After the acetone has been distilled off, an aqueous dispersion of dimethylformamide is obtained insoluble particles of about 30μ that settle but are easily redispersed.

Example 15
A. Preparation of the starting material

The pre-adduct is made as usual from 500 g of hexanediol-neopentylglycol-adipic acid polyester (OH number 67), 4 g of N-methyl diethanolamine, 90.5 g of 1,6-hexamethylene diisocyanate and quaternization with 3.12 ml of dimethyl sulfate manufactured. Instead of the acetone previously used as a solvent, 800 ml Methyl ethyl ketone with a water content of about 0.004% is used.

B. Preparation of the dispersion according to the invention

At a bath temperature of 60 ° C., one fifth of the pre-adduct solution is left in with stirring run in the solution of 2.75 g of diethylenetriamine in 240 ml of water for about 2 minutes. After distilling off of the methyl ketone, a dispersion of particles insoluble in dimethylformamide is obtained of about 50 μ, which settle but can be easily redispersed.

Example 16
A. Preparation of the starting material

An adduct of 500 g of hexanediol, neopentylglycol-adipic acid polyester (OH number 67), 4 g of N-methyldiethanolamih and 67.1 g of hexamethylene 1,6-diisocyanate is quaternized with 3.12 ml of dimethyl sulfate and dissolved in 800 ml of tetrahydrofuran.

B. Preparation of the dispersion according to the invention

The solution of 0.9 g of diethylenetriamine in 240 ml of water is left in at a bath temperature of 60.degree Stir into a fifth of the pre-adduct solution and the tetrahydrofuran is distilled off. It results an aqueous dispersion of particles insoluble in dimethylformamide of about 40 μ.

Example "17

A. Preparation of the starting material

209 g of hexanediol neopentyl glycol adipic acid polyester (OH number 67) are ^{stirred with 38 g of hexamethylene 1,6-diisocyanate at 120 °} C. for 2 hours. It is allowed to cool to 50 ° C. and dissolved in 700 ml of acetone. At a bath temperature of 60 ° C., 34.1 g of an aqueous 0.935 molar solution of the potassium salt of an adduct of 1,3-propane sultone and ethylene diamine (molar ratio 1: 1) are stirred in for 10 minutes. Sultone diamine adducts are described in German Auslegeschrift 1200 318.

B. Preparation of the dispersion according to the invention

The entire adduct solution is mixed with the solution of 4.88 g at a bath temperature of 60 ° C. while stirring Diethylenetriamine was added to 450 ml of water. The acetone is then reduced under reduced pressure distilled off, and a dispersion of particles insoluble in dimethylformamide of less is obtained than 10 μ. The dispersion is slightly creaming.

Example 18

The preparation of the starting material is carried out as in Example 18 with the difference that only 11 g the solution of the potassium salt of the diamine-sultone adduct is used. Also the dispersion production takes place according to Example 17, but with a solution of 6.25 g of diethylenetriamine in 450 ml of water. It results

809 637/1128

Claims (2)

A dispersion of particles in the order of 100 μ, which are insoluble in dimethylformamide immediately after preparation, settle, but can be easily redispersed by shaking, C Comparative experiment The experiment is carried out according to Example 18 with the difference that the water does not contain any polyamine is added. The freshly prepared dispersion is soluble in dimethylformamide. They change over time and completely clump together after a few days. Example 19 A. Preparation of the starting material 15 "500 g of pxopylene glycol 1,2-polyether (OH number 56) are stirred with 198 g of diphenylmethane-4,4'-diisocyanate for 1 hour at 90.degree Cool, add a solution of 10 g of N-methyl diethanolamine in 50 ml of acetone and stir for 30 minutes at a bath temperature of 60 ° C. After dilution with 100 ml of acetone, 7.8 ml of dimethyl sulfate are added and a further 30 minutes at 60 ° C. This solution is left to stand overnight and is diluted with 650 ml of acetone before further processing ml of water are added.- After the acetone has been distilled off, an approximately 27% aqueous dispersion of 20 to 80 μm particles which are insoluble in dimethylformamide and which settle but can easily be redispersed is obtained is game 19 procedure, only with the. Preparation of the starting material instead of 198 g of diphenylmethane-4,4'-diisocyanate 235 g are used, and in the preparation of the dispersion a solution of 2 g of pentaethylene hexamine in 400 ml of water is used. The resulting dispersion is similar to that of Example 19. Example 21. A Preparation of the starting material 2 g of N-methyldiethanolamine dissolved in 20 ml of acetone are stirred with 28.2 g of hexamethylene 1,6-diisoeyanate for 30 minutes at a bath temperature of 60 ° C. 1.56 ml of dimethyl sulfate are added and the mixture is stirred for a further 30 minutes. The solution of 100 g of a diamine with an average molecular weight of 1400 in 140 ml of acetone is then allowed to flow in at 20 ° C. and the mixture is stirred for 15 minutes. The diamine was obtained by reacting a polypropylene ether with nitrophenyl isocyanate and then reducing it according to US Pat. No. 2,888,439. B. Preparation of the dispersion according to the invention. According to the invention, a solution of 2.4 g of pentaethylene hexamine in 400 ml of water is allowed to flow into this solution at room temperature with stirring and the acetone is distilled off under reduced pressure. The result is a dispersion of polyurethane urea particles of 20 to 80 μm which are insoluble in dimethylformamide and which settle but are easily redispersible. Patent claims: 1. Process for the preparation of aqueous sedimenting, redispersible dispersions crosslinked polyadducts containing urea groups from NCO-polyurethanes .und · - Polyamines, characterized in that they are polyurethanes and / or polyureas with ionic. Groups and with free; NCQt . Groups in the presence of polyamines with more than two primary and / or secondary amino groups and / or hydrazine with water in any order or at the same time easy matching mixed up. 2. The method according to claim 1, characterized in that the mixing with in water dissolved or dispersed polyamines with more than two primary and / or secondary amino . groups and / or hydrazine takes place. Considered publications: German Auslegeschrift Nn 1 097 678. 809 637/1128 10.68 © Bnndesdruckerei Berlin