DE2025616B2 - Process for the production of microporous sheet-like structures by coagulating polyurethane solutions - Google Patents

Description

45

Ice is known, flat structures that are permeable to water vapor or coating from solutions of polyurethanes (e.g. dimethylformamide) by coagulation in nonsolvents (e.g. water) by a number of processes involving the Desired, microporous structure of the polymers by adhering to very specific and fixed Conditions to be achieved in the coagulation. Failure to comply with the special conditions will result on the one hand slightly macropores, d. h .. gross holes visible to the naked eye in the Foil, or the structure becomes unusable (*> uneven, the surfaces are uneven, or the microporous structure disappears critical phase of drying again with the formation of a non-porous, transparent translucent Foil. (15

The use of solutions of polyurethanes or polyurethane ureas in highly polar solvents such as dimethylformamide or dimethylacetamide. ij-'L-'jeltinvjulaiis inner Mitverwcndiinu otheri IOkmerer, such as polyvinyl chloride or polyacrylonitrile) / ur production of foils, coatings on CiJV-'eheti OUiM i'i! ! ' B. diving) with water. Gkeerin or other liquids that are feasible with the highly polar solvents mentioned, but are incompatible with the polyurethanes, have already been described in the German patent 8! <K Ibh . Don is also already the use of common solvents (which are non-losers for the polyurethane), z. B. methylene chloride, acetone or benzene mentioned.

A number of later patents give specific procedural principles to help with more or less improved security to the desired microporous structure. For example, in German Patent 1,110,607 Pt, coagulation is used proposed by PoK urethanes based on polyethers, hygroscopic polyurethane solutions (e.g. dimethylformamide serves as a solvent) one containing water vapor. to expose a circulating atmosphere, if necessary, which has a relative humidity of 15 to 1 fX)% at a Temperature of the dry thermometer from 10 to 3S C ". Due to the absorption of the water due to the hygroscopic solvent, the surface of the polyurethane is more or less less pronounced, probably with preforming the microporous structure. When placing the pre-gelled film or coatings in water the hygroscopic solvent is completely removed from the film with coagulation. Fail if the pregelatinization is effected by the action of the humid atmosphere indicated above, this is usually obtained transparent, non-permeable foils or coarse-pored, inhomogeneous foils, which are intended for the intended Purpose are useless.

In German Offenlegungsschrift 1 444 163 a modified method indicated where by adding smaller proportions of nonsolvents Iz. B. water) to the polyurethane solution this brought into a slightly cloudy, dispersion-like form which, if necessary, after heating after brushing on in flat form directly (i.e. without Pregelation in a humid atmosphere) in a non-solvent. like water, can be coagulated.

In the German Offenlegungsschrift I 444 165, a further process is specified, according to which, without pre-gelation, by direct coagulation in a mixed university! from non-solvent and solvent Iz. B. dimethylformamide, H ₂ O 10:90 to 95: 5) microporous films are to be obtained.

According to a further variant, which is described in Belgian patent 624 250. So much nonsolvent is added to the polyurethane solution. daf. ¹ you can separate the gel of the polymer, first spread this gel onto the substrate and coagulate in non-dissolver (water) to form a microporous structure.

In this last mode of operation, it is technically difficult to separate the gel and unite it to process homogeneous coating. The Arbeilswcisi according to German Offenlegungsschrift 1444 165 research dcrt longer coagulation times, especially for baths with a lot of solvent, because of the polyuretic only slowly coagulates. So the capacity of a given production facility will be greatly increased set. In addition, according to this procedure!

nsi 'structures only with low security and iilleuhar on selected i'olyup.Hhan / iisanimeiiscr / ui-uc-n can be obtained to a limited extent.

Home work according to German OfkuilcguugYv.iinli ί 444 ί (). ΐ it is difficult to find the right menu au Ntchllösur.gsmittel for the preparation of the colloidal.: !! Dispersions to imTen. The process uses raw materials in an insiatiilcn state, because the The characteristics of the dispersion change over time and depending on temperature and humidity. wherein the elastomer dispersions change into a pasty, no longer smoothly deformable state.

The working method according to German AiKlegeschrifl I IiO 607 requires one to be accurate in its humidity k "iu! itionierie atmosphere and long exposure - /. '■ l in this humid atmosphere. The results are, however, hardly reproducible. So obviously can also only polyether urethine can be processed. A relatively low productivity is achieved here low security and application range achieved.

According to the suggestion of the German standard specification I SO3O21 has a drier or more humid effect Gas flow with a certain flow velocity A layer of polyurethane solution applied over a large area through moisture or through Evaporation of the solvent forms a dense, gelled layer on the surface of the surface Solution formed. Then z. B. coagulated in water. As will be explained in detail, it is expedient and it is desirable that the temperatures are not above 50.degree. C., preferably not above 30.degree.

In the German Auslegeschrift 1238 200 becomes stated that direct coagulation of elastomers leads to microporous structures when one in baths, which are heated in the vicinity of the boiling point of the Ba lefliquid. z. B. in hot water coagulated at 95 ° C.

Furthermore, German Auslegeschrift 1 270 276 teaches the polyurethane solutions to be coagulated 10 to 30 percent by weight of a cationic containing quartz ammonium nitrogen atoms Polyurethane dispersion, up to 7 percent by weight of water and optionally up to 2.5 percent by weight to add anionic, synthetic tanning agents.

After this procedure, after treating the coated polyurethane solution with candlesticks Air and subsequent coagulation in water or aqueous solvent mixtures are permeable to water vapor Polyurcthandeckschichtcn substantially safe uls manufactured in the previously described process Will.

When pretreating with moist air, this procedure requires the

a) when adding commercially available tanning agents to the coagulable polyethane solution with use from 10 to 30 percent by weight of cationic polyurethane dispersion not below 10 mins,

b) in the aftertreatment of the coagulated polyurethane top layers in aqueous neutralized dye solutions not less than 20 minutes and

c) without the use of tanning agents as an aid, not less than 30 minutes new.

The task of the fulfillment is an economic process for the production of microporous polyurethane top layers, without these complex measures! without additional chemical additives toggle. that is carried out continuously can.

This method provides increased production security and, in particular, increased production speed and with little equipment expenditure improved microporous flat structures, wöbe Advantageously, the use of the cationic polyurethane dispersion can also be dispensed with

ι :, The invention relates to a method Manufacture of microporous flat structures from polyurethane by pretreating thin layers of polyurethane solutions. oie mitcinei, if applicable aqueous canonical polyurethane dispersion ver

ι ς mixed: are increased in a moist atmosphere Temperature. Coagulation of the layers in water or aqueous dye baths with removal of the major part of the Polyureihanlösi'ngsmittel.s and subsequent Drying, characterized in that the

: o thin layer of the polyurethane solution in a water vapor atmosphere with a relative .. humidity of at least.! 50 "η at temperatures of at least fo C 0.1 to 60 minutes, after which coagulation the microporous polyurethane, given

> _s nenfalis with an aliphatic alcohol. Treated for 0.2 to 30 minutes and then dried. Solvents for polyurethanes which can be used to carry out the process of the invention are preferably highly polar, hygroscopic, water-soluble organic solvents! with amide. Urea or sulphoxide groups, particularly preferably with boiling points above 130 " ¹ C. They must be soluble in water or the aqueous precipitation baths. Examples of suitable are dimethylformamide, dimethylacetamide, tetramethylurea, dimethylsulphoxide, diethvlformamide, formylmorpholine. Hxamethylphosphoramide or mixtures thereof. These In the following, solvents are understood as “solvents” or “solvents”.

These “solvents” can also be mixed with “nonsolvents” or “nonsolvents”. These are liquids that do not dissolve the polyurethanes (and preferably only swell little) or are inert to polyurethanes. The preferred nonsolvent is water. There come but also, for example, hydrocarbons such as benzene or chlorobenzene, aliphatic alcohols such as methanol or ethanol. Ethers, such as dioxane or tetrahydrofuran, or esters, such as ethyl acetate, in

■ so question.

The coagulation bath preferably consists of water. But there can also be baths that are not water still contain a (water-miscible) non-solvent (as defined above) can be used. In special ■. In some cases, pure alcohol baths are also used. preferably from aliphatic alcohols, such as Methanol or ethanol. Mixtures of water and a "solvent" are also suitable according to the definition given above.

bo It was surprising that so at high temperatures and intense action of concentrated steam a safe, smooth and fine-pored Vorgclicrung is achieved, the mi (considerably wider process safety than the vorbeschric-

6s benen process too well microporous coagulated Leads to flat structures with a good surface. The previous methods used relatively low water drainage pressures Iz. B. Deuische Ansln.r ^ rhrift 1 1 iniv, 7

at 10 to 3RC, and 15 to 1 (X) ⁰ ZoJyCr relative humidity, corresponding to a maximum of about 50 Torr) and "preferably C ₁ not higher than 30" refer to it as desired, daf3 the temperature not higher than 50 Cist (see FIG. German Auslegeschrift 1 803 021, p. 6/7). when the pre-gelation of the solution is carried out in a thin spread.

The water vapor atmosphere for filling the process according to the invention should contain at least 50 ⁰ Z ₀ , preferably 80 to 100% relative humidity at temperatures above 65 ° C, preferably 75 to KX) C. It is most expedient to work in the specified temperature range with a water vapor atmosphere that is as saturated as possible, e.g. B. with saturated steam or steam atmosphere over boiling is water. For a continuous manufacturing process, the additional presence of an inert transport gas, in the simplest case air, is important for the technical control of the flow conditions in the gas phase. In practice, the desired gas mixture, which is almost saturated with water vapor, can be produced by mixing superheated steam and transport gas before contact with the pierced polyurethane solution. The water vapor atmosphere should generally be brought into contact with the polyurethane solution at a negative pressure of a few millimeters of water column. However, you can also work under a slight excess pressure.

The optimal exposure time to the steam atmosphere can be different for polyurethane mixtures Composition can be determined in simple preliminary tests. It is generally 0.1 to 30 minutes, preferably 0.5 to 3 minutes.

When exposed to the concentrated water vapor atmosphere at high temperatures, the Polyurethane solution or mixture a gelled polyurethane layer, which then the further coagulation controls the solution with the formation of micropores. Therefore, in general, the outermost layer is the obtained microporous film somewhat denser than the interior.

However, this is desirable because it makes the films easier to use.

It is heated in dry air at about 80 to 100 "C c'ie on z. B. Polyurethane solution painted on glass plates and then immersed in water, the desired result will not be achieved. On the other hand, if you spray the painted polyurethane solution with a fine liquid mist, so form on the concrete The points of contact of the fine water droplets with the solvent surface are discrete, visible Macropores with the formation of an inhomogeneous surface.

The process can be carried out batchwise or continuously in various embodiments will. For development or testing purposes, one can, if necessary, paint on glass plates heated polyurethane solution over a container of hot or boiling water, in a sealed Pre-gel the space (discontinuous operation). One can also get saturated or overheated Introduce steam into a room of the appropriate temperature, in which the Solution is located. No drops of condensation should fall on the gelling polyurethane. this can by appropriate design of the ceiling of the Gclierraiimes or z. B. by heating the ceiling and / or the coagulation pad can be prevented.

For continuous implementation, the polyurethane mixture can be carried out continuously in the customary manner pour onto an endless carrier, e.g. B. with doctor blades or slot casting, then if necessary a short one to even out the applied solution Convey the piece without the action of steam or subject it to a vacuum acting from the underside (for Direct coating and impregnation of textiles such as woven, knitted or non-woven or felt-like fabrics Materials) and then through the treatment room containing hot water vapor If necessary, the carrier material can also be heated.

Water or aqueous solutions of the polyurethane solvent can be used as coagulating liquids Consideration, e.g. B. water. Dimethylformamide, mixtures up to a mixing ratio of about 1: 1. One can Provide a coagulation bath or several coagulation baths of different composition one after the other. The bath temperatures are preferably 2 (up to 35 C: however, higher and lower temperatures can also be used Temperatures used or if several baths are used, temperatures and concentrations vary will.

If you use a concentrated wipe as the last wash Alcohol solution, preferably methanol, se the microporous structure is stabilized and the subsequent drying is made much easier. The drying after squeezing off excess liquid. done in conventional hot air dryers will.

For the preparation of the solutions suitable poly urethanes are in particular rubber-like polyurethanes In principle, all polyurethanes can be used, but their tendency to develop dei microporous structure is different. The formation of microporosity can be achieved by adding cationic agents see polyurethane dispersions to make polyurethane soluions much easier, but occasionally increases with it a deterioration in the mechanical strength of the microporous film is accepted. The amount of cationi shear polyurethane dispersion should generally not exceed 35 percent by weight. Preferred one takes 0.5 to 20 percent by weight and br-onder: advantageously 0.5 to 10 percent by weight. Percentanga ben refer to the solids in the polyurethane solution and the dispersion.

The cationic polyurethane dispersions are particularly effective in the continuous production of the micro regulating and stabilizing porous fabric when treated with steam and both subsequent coagulation. You thus improve production reliability and increase production speed.

Furthermore, you can add additives without impairing the coagulation behavior, for. B. Poly vinyl chloride or its copolymers, polyacrylic nitrile or its copolymers, commercially available anionic tanning agents, carboxymethyl cellulose, polyalkyl (meth) acrylates, emulsifiers, optical brighteners Antioxidants, special light stabilizers, wi Ν, Ν-dialkylhydrazides, crosslinking substances zen, such as paraformaldehyde, melamine hexamethylol ether or other formaldehyde derivatives, Pclyisocya nate, quaternizing agents or polyaziridine urine

substances and dyes, usually insoluble l'igmcrile.

Fun spe / icllcr F'.influB on the Koagulicrbarkcil the Polyurethane solutions can be coagulated by adding nonsolvents, preferably water drive polyurethane systems. The highest possible amount of nonsense liquid has been reached when that Polyurethane begins to fail. Also by using the cationic Polvuicthandispeision Non-solvent milk (water) can be introduced into the system. In this case, too, you can also add non-solvents. In general, the nonsolvent is not given in pure form but in a mixture with solvent. so uses / B. a dimethylformamide water mixture, is The total content of nonsolvents in the coagulable mixture should generally not be 9% exceed.

Fine further influencing the coagulability results from a thermal pretreatment of the polyurethane mixtures that may contain nonsolvents. about short-term warming, e.g. B. up to 2 hours at 70 to 100 C or 2 to 20 hours at 40 to 70 "C, or by letting such polyurethane mixtures stand for a long time at room temperature. especially if they contain small amounts of nonsolvents. The ready-to-use Polyurcthannii .-. Chungen can have viscosities between 1 and 1000 P. preferably 10 to KX) O P.

The solid grocery store for ready-to-use polyurethane mixtures should be between 5 and 40 percent by weight, preferably between 10 and 30 percent by weight lie.

For the production of the polyurethane solutions for the process according to the invention, a large number of The most varied of methods accessible products are suitable, but all of which have the typical urethane grouping included (cf. Ul 1 ma η n. Encyklopadie der technischen Chemie, 4th edition. Rd. 14, p. 338 bis 363). It can, for example, be polyurethanes in the narrower sense, which are composed of high molecular weight Polyhydroxy compounds, dialcohols and diisocyanates are accessible by single or multi-stage processes (via NCO pre-adducts). For example can polyesters or polyethers with an excess of diisocyanates to form NCO pre-adducts implemented and then with diol compounds such as butanediol-1,4, N-methyl-diethanolamine. Hydroquinone bis (hydroxyethylene ether) or terephthalic acid bis-hydroxyethyl ester, has been reacted in equivalent or slightly less than the amount be, where you can work both in the melt and in solvents. But you can also have implemented the above components in a classification process for polyurethane and then have dissolved in highly polar solvents.

However, polyurethane ureas, as described as "components a" in German, are particularly suitable Auslegeschrift 1 270 276 are described. For their production are higher molecular, essentially linear polyhydroxy compounds with terminal hydroxyl groups with a molecular weight between 400 and 5000 and optionally other low molecular weight dialcohols, amino alcohols or diamines with an excess of diisocyanates initially to a pre-adduct with terminal isocyanate groups implemented and this then with water or with bifunctional compounds that at least contain one of their isocyanate-reactive hydrogen atoms bound to nitrogen atoms, implemented. Because of its significantly higher reactivity and conversion rate compared to diols This chain-lengthening agent, this reaction is preferred in highly polar, water-soluble Solvents, with a boiling point 100 ('carried out.

The production of such PohurethanharnstolTe and their solutions is for example in the German Patent specification! ·!) 88X766.1 123 467.1 150517. | 154937. the German scripts I 161007. I 183 196.

1 1X6 618. Belgian patents 649 619. 646 637, 658 363, 664 344, 664 346, 666 208. French patents 1380082. I 371 391. 1,383,077 and U.S. Patents 2,929,803,

2 929 804. 3 040 003.

Higher molecular. essentially linear polyhydroxy compounds with terminal hydroxyl groups used in the manufacture of rubbery polyurethanes are suitable. are /. B. polyester. Polyester amides. Polyether. Polyacetals. Polycarbonates or Poly-N-alkylurcthanc or mixtures thereof, too those with window, ether. Amide. Urethane. N-alkyl urethane groups with molecular weights between 400 and 5000 and melting points of preferably +60 to -50 ° C., suitably below 45 ° C. (polyhydroxy compounds with higher melting points can lead to excessive hardening of the finished products at temperatures around or 0 C.)

Particular mention may be made of polyesters made from adipic acid and dialcohols or mixtures of dialcohols. e.g., ilium glycol. Propylene glycol. Bulandiol-1.4. 2,2-Dimethylpropanediol-1,3. 1,6-hexanediol or bishydroxymethylcyclohexane. Diols or mixtures of diols with five or more carbon atoms are preferred because of the good hydrolysis resistance of the polyester made from it. Polyester by condensation of caprolactone and diols or amines, such as hexanediol-1.6. with narrow molecular weight distribution are also suitable. Particularly good microporous films with excellent Surface properties and good water vapor permeability are derived from mixed polyesters, that of 90 to 60 percent by weight adipic acid and 10 to 40 percent by weight terephthalic acid and one Diol. preferably ethylene glycol, 1,4-butanediol, neopentyl glycol and / or 1,6-hexanediol.

Polyurethane ureas with excellent hydrolysis resistance can also be obtained from polyethers, preferably from polytetramethylene ether diols, which can also be used as mixed polyethers nen.

Suitable diisocyanates, if appropriate a mixture, are aliphatic, cycloaliphatic, araliphatic table, aromatic diisocyanates or heterocyclic diisocyanates. Diisocyanate may be mentioned in particular with symmetrical structure, e.g. B. diphenylmethane 4,4'-diisocyanate, diphenyldimethylmethane-4,4'-di isocyanate. 2,2 '- 6,6' - tetramethyldiphenylmethane diisocyanate. Diphenyl-4,4'-diisocyanate, diphenyl ether - 4,4 '- diisocyanate or its alkyl, alkoxy! or halogen-substituted derivatives, also toluene 2,4- or 2,6-diisocyanate or their technical products see, diisopropylphenylene diisocyanate, m-xylylene isocyanate, p-xylene diisocyanate or a, a, a ', a'-tetn methyl-p-xylylene diisocyanate or other alkyls thereof

309 586/4 ^

2 025 S16

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or allalogensubstitution products.diinciesToluvlen 2,4-diisocyanate. Bis (3-methyl-4-isocyanatophene) urea or naphthylene-1,5-diistitanal. Alipiiatischc Diisocyaiiaic. such as hexamelhylenediisoeyanate. Cyclohexane - 1.4 diisocyanate. Dieyclohew! Methan->

4.4 -diisoeyanate. I - isocyanato-3-isocyanatomethyl-3,5.5 - trimciliylcyclohc.xan or 2.2.4 - Trimelhylliexan-l. (S-dii-iicyanat. can be used and produce very little discolouring products when exposed to light. | "

Diphenylmctlian-4.4 -diisoeyanat, the isomeric toluene diisocyanates. p-xylylene diisocyanate, and, if appropriate, partially methylated methylene diisocyanate or dicyclohexylated methylene-4,4'-diisocyanate. used. is

The higher molecular weight poly hydroxyl compounds are mixed with the diisocyanates !! roughly in the molar ratio I: 1.25 to I: 4.0. optionally in several stages in the melt or in inert to isocyanates Solvents such as tetrahydrofuran. Dioxane or chlorobin / .ol or dimethylformamide, at temperatures from about 20 to 130 ° C. preferably 40 to 100 ° C. implemented.

Such reaction times are observed. that an essentially linear pre-adduct with terminal NCO groups is obtained which, when reacted with approximately equivalent amounts of bifunctional chain lengthening agents, yields an essentially linear elastomeric polyurethane or polyurethane substance which is soluble in polar solvents. ^ ₀

Hs can, together with higher molecular weight polyhydroxy compounds, also lower molecular weight diols (molecular weight preferably below 250) .ζ. 3.Atine glycol. Butanediol-1.4. Bis-NN - (, i-hydroxyäthyi) -methylamine. Bis - NN - (/ ■>' - hydroxypropyl) - methyl- 3s amine, N.N'-Bis-hydroxyäthylpiperazin or Hydroehinon-bis - (/ i-hydroxyä thy lather) can be used with. The amount of low molecular weight diols can, for. B. be dimensioned so that per mole of OH groups of the higher molecular weight poly hydroxyl compound 0.1 to 3 moles of OH groups of the low molecular weight diol are present. Diols with tertiary nitrogen increase the colorability. improve the light resistance and create the attack sites for further post-treatments, e.g. B. Crosslinking with strongly alkylating compounds.

The NCO group content of the pre-adducts (calculated on the solvent-free pre-adduct) is from of decisive importance for the properties of the polyurethane ureas obtained from them. He must be at least 0.75 percent by weight and should preferably be between about 1.00 and about 7.6 percent by weight, especially between about 1.5 and

5.5 percent by weight, so that the polyurethane ureas sufficiently high melting points, tensile strengths, elongations at break and stress values exhibit. In the case of the chain extension reaction with water, the NCO content is preferably higher,

z. B. between 3.5 and 7.6 percent by weight, since some of the NCO groups are saponified to form amino groups will.

The chain extenders should have a molecular weight from 18 to about 500, preferably from 32 to 350, and can optionally be in Mixture or staged implementation can be used. In addition to water, these include, for example Ethylenediamine, 1,2- or 1,3-propylenediamine, 1,4-tetramethylene diamine, 1,6-hexamethylene diamine.

2.2.4 - Trim unhexanediamine - 1.6. I - Methylcyclohcxane-2.4-diaiiiin. 4.4'-diaminodicycloxyl methane. Bis (aminopropyl) mclhylamine. NN - Bis - (aminopiopvl) - pipera / .in. araliphalic diamines, such as 1,5-tetrahydronaphlhalin, or aromatic diprimary amines, such as 4,4'-diaminodiphenylmethane. 4.4 Diainino diphenyl ether. I - methyl-2,4-diaminobenzene or araliphatic diprimary diamines, such as m-xylylenediamine. p-xylylindiamine, a, a, a ', a'-tetramethyl-p-xylylindiamine or I.VBis - (/ f-aminoisopropyD-benzene. also sulfonic acid group-containing diamines, such as 4.4'-diamino-silbenes ■ 2,2'-disulfonic acid oiler 4.4 - Diaminodiphynylethane-2,2-disulphonic acid, hexamethylenediamine-1,6-N-butylsulphonic acid c. 1.6-hexamethylene-3-sulphonic acid or its alkali salts /.id. Tercphthalic acid dihydrazide, isophthalic acid dihydrazide, β- scmicarbazidoethane carbazine ester. jl -Aminoethylscmicarbazide, / f-semi-arbazidopropionic acid hydrazide. Secondary diamines, preferably with a symmetrical structure, such as piperazine or 2,5-di melhylpipcrazin, can be used.

When using chain extension mixtures As a rule, the solubility of the polyurethane ureas increases. and the melting point of the polyurethanes decreases. Preferred chain extenders include ethylenediamine, m-xylylenediamine, Hydrazine. Carbodihydrazide, aliphatic dicarboxylic acid hydrazidec. such as glutaric acid dihydrazide, and water is also used. Will these chains lengthen used together with others, their amount should be at least 50 mole percent, preferably more than 80 mole percent of the total.

The reaction of the NCO-Voradduktc with the chain lengthening agents is carried out in highly polar water-soluble than 130 ⁿ C-boiling solvents. Mention should be made of solvents containing amide or sulfoxide groups with the ability to form strong hydrogen bonds, for example dimethylformamide, N-methylpyrrolidone, diethylformamide, dimethylacetamide, formylmorpholine. Hexamethylphosphoramide, dimethylsulfoxide, tetramethylurea or their mixtures. The technically preferred solvent is dimethylformamide . Up to a certain proportion, which is about 35 percent by weight of the amount of solvent, less polar solvents, which are not capable of dissolving the polyurethane ureas, can be added to the highly polar amide solvents, e.g. B. tetrahydrofuran, dioxane, acetone or GIy kolmonomethylälheraceiat. The concentration de; Polyurethane solutions should preferably be about 5 weight percent to 33 Ge, be particularly 1 5 to 27 weight percent, with the preferred viscosities zwischei 1 and 1000 P, especially between 50 to 800 P / are intended to be 25 ° C.

Further suitable polyurethanes are also those produced by the reaction of bis-chlorohienoic acids. th and diamines or from bis-carboxylic acid chlorides and diamines (with preference

each of the components has a volatile molecular structure Compound with a molecular weight of about 400 to 5 (KK) is). May be mentioned by way of example Conversion products of high molecular weight bis-chloramic acidic acid of polyhydroxy compounds with diamines as well as reaction products of liquid molecules Compounds with amino end groups (manufactured / .. B. from polyhydroxyl compounds. Diisocyanalcn and chain lengthening with appreciably excess amounts of NH ^ end groups Scoop lengthening agents) and bis-acid chlorides or bischloramic acidic acids. Such connections are z. B. in the USA, -Patent 2929801. 2 929 802, 2 962 470, 2 957 852. Segmcntierte polyester or Polyethermcthanc are also suitable. as described, for example, in French patents 1,354,553 and 1,359,090 and in Belgian patent 574,385. At produced by drying the solutions Solid foils made from these polyurethane solutions can have mechanical strength values or elastic properties, z. B. determined after cutting the foils to strips or threads. Solid foils made for Polyurethanes particularly suitable for the process according to the invention have the following properties:

1. Melting point on the coffin bench at least 180 C _1, preferably above 2 (H) C.

2. Tear strength of at least 200 kg / cm 2, preferably 300 to 8 (X) kg cm ² .

3. Elongation at break at least 2 (X)%. preferably 400 to 800%,

4. Tension forces with the first expansion to 20%: at least 5.0 kg / cm ² , preferably K) up to 30 kg / cm ² : with the expansion to 100%: at least 20 kg cm ² . preferably 45 to 75 kg / cm ² , with the first expansion to 300%: at least 60 kg cm ² , preferably 80 to 580 kg / cm ² .

5. Molecular weight corresponding to an intrinsic viscosity ι /, of at least 0.6. preferably 0.90 to 1.9

In 'ir C

with C = concentration in g / 100ml. / _{/; i} = viscosity of a I weight percent solution of the polyurethane

in phosphoric acid trisdimethylamide at 25 Cj.

6. Insolubility in weakly polar solvents such as tetrahydrofuran, dioxane or glycol monomethyl ether acetate to solubility in highly polar solvents, such as. B. dimethylformamide.

To convert the strength and modulus data from kg / cm ² to g / dtex or mg / dtex (see for example Table 1 or Table 8), the following relationship applies:

χ = "· y · 10 ³

where the measure of the tensile strength or of the module in kg / cm ² , y is the measure of the tensile strength or of the modulus in g / dtex, η is the measure of the density in g / cm ³ .

If the tensile strength or modulus values y are expressed in mg / dtex, then the relationship χ - η ■ y applies, where χ and ρ have the above meaning.

Pol) iircthan solid films generally have the following Density:

Polyester polyurethanes η - about 1.2 g / cm '
Polyäthcrpolyurelhanc π = about 1.0 1.05 g / cm ¹

The density of microporous films is generally between 0.5 and 1.0 g / cm ³ .

In a particular embodiment of the method of the invention, the coagulant can Cationic aqueous polyurethane dispersions are added to polyurethane solution, in amounts up to 35 percent by weight (based on solid polyurethane). In particular, these are quaternary ammonium groups containing polyurethanes with a certain hydrophilic character, which in water or aqueous liquids e.g. B. water / dimethylformamide mixtures. preferably in mixed proportions 1: Use emulsifiers or wetting agents that are dispersed or colloidally dissolved.

Canonical polyurethanes suitable for this are obtained, for example, in accordance with the German Auslegeschrift 1270 276, if at least one component with one or more basic components is used in the construction of the polyurethane Additional nitrogen atoms have been used and the basic tertiary nitrogen atoms of the polyurethane have been reacted with alkylating agents or inorganic or organic acids. It is basically irrelevant at which point of the polyurethane macromolecule they are based Nitrogen atoms are located. Polyurethanes with reactive quaternizing capabilities can also be used React halogen atoms with tertiary amines. Furthermore, you can also use polyurethanes Establish chain-building quaternization by z. B. from optionally higher molecular weight diols and isocyanates with reactive halogen atoms or diisocyanates and halogen alcohols dihalo urethane produces and converts these with ditertiary amines. Conversely, you can make connections with two isocyanate groups and tertiary amino alcohols produce ditertiary diaminourethanes and convert these with reactive dihalophene compounds. Of course, Jie can be cationic Polyurethane compound also made from a cationic, salt-like starting component, such as a quaternary one basic polyether or an isocyanate containing quartz nitrogen. These manufacturing methods are e.g. B. in the Auslegeschriften 1 184 946, 1 178 586, 1 179 363 and Belgian patents 653 223, 658 026. 636 799. The starting materials suitable for building up the salt-like polyurethanes can also be found there listed.

In addition to the urethane groups, the polyurethane composition can also contain urea groups.

In order to obtain a satisfactory set of properties in the end product, the urethane content should and optionally urea groups are 8 to 35 percent by weight of the polyurethane composition. Dei The content of quaternary ammonium groups should be approximately 0.5 to 2.0 percent by weight, preferably 0.8 to 1.8 percent by weight of the polyurethane mass

The aqueous dispersions or colloidal solutions of these cationic polyurethanes have particle sizes between about 10 and 1000 πΐμ. Sk can also contain organic solvents in quantities of up to about 50%, for example acetone or Dimethylformamide. So you need that to

Positioning of the dispersion according to the German Ausleeeschrifien 1 84 94, 1178 586 or the Belgian Patent 653,223 does not and can not remove the solvent used from the dispersion formed In addition, high-boiling solvents, such as dimethylformamide, in the preparation of the dispersion use.

Cationic polyurethanes made from higher molecular weight are preferred for the process according to the invention Polyhydroxy compounds with a molecular weight of 500 to 5000. Polyisocyanates, a basic one Chain extender with tertiary, preferably aliphatically substituted nitrogen atoms, such as. B. N - methyl diethanolamine. N, N - bis (aminopropyl) methylamine, and optionally other non-basic chain extenders, as preferred Dialcohols or diamines. Water. Hydrazine or substituted hydrazines are made. Preferably contains the predominantly linear, in organic solvents such as dimethylformamide, cold soluble polyurethane mass 5 to 12% N-methyldiethanolamine built-in. From the tertiary nitrogen built into the polyurethane mass as a result become 10 to 60% with an alkylating agent. such as dimethyl sulfate, methyl chloromethyl ether. Dietary sulfate or bromoethanol, quaternized and 30 to 70% with an acid such as hydrochloric acid. Lactic acid or acetic acid, neutralized in the presence of water. 10 to 20% of the tertiary nitrogen is generally used not converted to salt. ·

Preference is given to finding, at least in part, bi- or trifunctional alkylating agents. like dibrombulan. p-xylylene dichloride, 1,3-dimethyl-4,6-bis-chloromethylbenzene, methylene-bis-bromoacetamide. Trimethylolpropane - tris - chloroacetic acid ester or bi- or tri- \ s functional acids with pH values below 4, such as phosphoric acid, oxylic acid or sulfuric acid, each used as an aqueous solution, whereby these mainly react monofunctionally and then exert a crosslinking function in the finished microporous fabric .

These cationic polyurethanes are then dispersed in Wa scr. For later networking you can the dispersed polyurethanes of course also z. B. Mcthyloläthergruppen included.

The mechanical strength values and elastic properties of the microporous fabrics are determined in the same way as the corresponding values for the solid film made of the polyurethane elastomer components. Naturally, the higher the microporous films, the lower they are is the water vapor permeability of the materials.

The determination of the water vapor permeability is carried out according to the method of I UP 15. given in »Das Leder«, 1961, pp. 86 to 88. which describes the "water vapor permeability in, ι delivers (measurement at

Normal pressure and a relative humidity of 65% at 20 "C) or according to a new method, which (*> allows much faster determinations and the so-called permeation coefficient as a measured value provides, which describes the water vapor permeability through a film of normalized thickness. the Measurement b / .w. the evaluation of the milking results c f, s is done as follows:

A circular film sample with a diameter of 2 cm is removed from a rope with saturated! Contaminated with water vapor. The amount of water permeating through the effect of the satiating steam pressure of 18.7 Torr at 21 ° C. is frozen in a cold trap and then determined by thawing the cold trap and measuring the vapor pressure that is established in the known measuring volume. The permeation coefficient PK is obtained in ^. _cn ^ .j _liri ■

which is the amount of water in grams angihi. which passes through a film with an area of 1 cm and 1 cm thick at a differential pressure of 1 Torr. (Dimension: gh · cm Torr.l The numerical values of the PK-Weries are given in the following in each case ^{multiplied by 10 M.} (For literature see: La \ d'Ans. Springer-Verlag. W3. S. IIIS.) The determination of the Elongation at break, as well as the modules and other elasticity values on the microporous foils, are carried out as described on the solid foils.

The strength values of the microporous films are naturally all the lower, the greater the water vapor permeability b / w. is the PK value. Even with the same water vapor permeability the respective physical properties still depend crucially on the quality and uniformity the microporous structure. which is determined by the coagulation process used will.

There is a particular value in the invention Method is that uniformly microporous films with good surface compared to others Process of increased strength values, reduced thermoplasticity. improved abrasion properties can be achieved with high permeabilities, while at the same time the process is shortened in terms of time can.

The polyurethane solution is used for the continuous production of the microporous surface structures or a mixture of polyurethane solution and cationic dispersion to a porous or non-porous one Substrate, e.g. B. by spreading. Pouring or squeegeeing on, leaves the applied layer a Pass the treatment room with water vapor, whereby gelling enters a foil and bathes the material then in coagulation. Washing and post-treatment baths, the last of which can be an alcohol bath. The microporous material is then dried.

The applied layer thickness depends on the desired final thickness of the microporous surface structure The layer thicknesses of the applied polyurethane mixtures are normally from 0.5 to 1.5 mm will be sufficient. A porous substrate will be chosen if this is made of polyurethane is to be coated directly. As porous substrates are, for. B. called, tissue. Knitted fabrics. Fleece or Felts.

A non-porous substrate, e.g. B. glass plates. McIaII tapes (if necessary with a structural surface) or with plastics, /. B. Pcrfluorpolväthylcn. coated Fabric sheets are used when porous polyurethane films are desired. who took off and on other z. B. transferring porous substrates, e.g. B. to be glued. Suitable Substrates are e.g. wood. Split disc. Cardboard. Paper or woven b / w. ungwcwcwcwcbted textile fabrics c Masonry or metal.

A. Try without using a
cationic polyureihandispciMon

Al) Manufacturing instructions for Jic
Polyurethane solutions

PoIv urethane aι

6000 parts of an adipic acid mixed polyester (1,6-hexanediol and 2,2-dimethylpropanediol in a molar ratio of 65:35) with an OH number of 66.3 are mixed with 1550 parts of diphenylmethane-4,4'-diisocyanate and 1895 parts of dimethylformamide for 170 minutes 50 C until the NCO content of the pre-adduct solution entrusts 2.35%! Corresponds to 2.93 ", NCO in the solid). In a 70 C solution of 190 parts of carbodihydrazide in 16010 parts of dimethylformamide, 7525 parts of the above NCO adduce solution are added with stirring allowed to flow in, a clear, homogeneous solution with a viscosity of 506 P being formed.

Polyurethane b |

IO (X) parts of an adipic acid mixed pile yesteryear (Ethylene glycol / Bulandiol-1.4 in a volumetric ratio of 1: 1) the OH number 54.8 with 233 parts of diphenylmethane-4,4'-diisocyanate and 310 parts of dimethylformamide heated to 50 C for 80 minutes until the NCO content the solution is 2.26% (corresponds to 2.84% NCO in the solid substance). In a 70 C hot solution of: 1.15 parts of carbodihydrazide in 2730 parts of dimethylformamide are 1290 parts of the above NCO pre-adduct solution stirred in, resulting in a viscous solution (270 P / 20 "C). After stirring in 2.35 parts of hexane-1.ö-diisocyanate becomes clear. homogeneous solution with a viscosity of 530 P obtained.

Polyurethane c)

800 parts of an adipic acid-butanediol polyester The OH number is 119 with 314 parts of diphenyl methane 4,4'-diisoeyanate and 280 parts of dimethylformamide reacted for 25 minutes at 55 ° C. until the NCO content 2.93% (based on solids). 421 parts of this solution are mixed with a solution of 10.82 parts Carbodihydrazide in 910 parts of dimethylformamide to a clear, homogeneous solution 1750 P 20 C) mixed.

Polyurethane d)

800 parts of a butanediol / adipic acid polyester The OH number is 113 with 305 parts of diphenyl methane-4,4'-diisocyanal and 277 parts of dimethylformamide heated to 50 C for 25 minutes until the NCO rate has fallen to 2.98%. 413 parts of the NCO pre-adduct are dissolved in 11 parts Carbodihydrazide stirred into 910 parts of dimethylformamide, a homogeneous solution of 650 P. is obtained.

Polyurethane c)

8 (X) parts of a butanediol -1,4 adipic acid poIvesters the OH number 69.3 will be with 2! 7 parts of Diphynylmclhan- ^ '- diisocyanate and 253 parts of dimethylformamide for 25 minutes at 55 C / um NCO precursor implemented. 413 parts of this NCO pre-adduct are mixed with 11.0 parts of carbodihydrazide and 910 parts Dimethylformamide to the solution (400 P) imigesei / i.

LO

Polyurethane II

In it parts of the poi> es! Cr "described in ai (Uli number 66. '. ¹ I are mixed with 50 files 2.2-dimethj! Propane diol-1.3. 373 parts diphen / methane-4,4-diisoc \ an.i and 35 ('i parts of dimethylformamide 50 minutes at 60 C to the NCO-Voraddiiki 12.39 "» NCO in the solid substance). 316 parts of the same are converted into a solution of 6.6 parts of carhodihvdrazide in 681 parts of dimethylformamide with the formation of a homogeneous solution (600 P. ) entered. ,,, = 1.26.

Polyurethane gl

KX) O parts of the polyester from al. 239 parts Diplien_v! Methaii-4.4-diisoeyanat and 310 parts of dimethylformamide are converted to the NCO pre-adduct at 45 to 50 ° C. for 57 minutes, and 212 parts of the same into a solution of 4.42 parts of carbodihydrazide in 452 parts of dimethylformamide to form a Solution of viscosity 1010 P entered.

PoIv urethane h)

K) (M) TeUc of an adipic acid-He \ andiol-l.6 / 2,2-Dimethylpropanediol-1.3 mixed polyester (Diol ratio 65:35) the OH number 65.9. are made with 250 parts Diphenyl methane-4,4-diisoeyanate i: nd 313 parts of dimethylformamide Heated for 125 minutes at 45 to 50 C until the NCO content is 2.6% (based on solids) amounts to.

269 parts of the NCO pre-adduct solution are added to a suspension prepared by adding 5 parts solid carbonic acid in a solution of 3.56 parts of 94.2% hydrazine hydrate in 562 parts of dimethylformamide, entered under formation of a homogeneous solution (565 P 20 C).

Polyurethane i)

269 parts of the NCO pre-adduct solution prepared according to the previous example are poured into a suspension produced by throwing solid carbonic acid into a solution of 4.10 parts of ethylenediamine in 562 parts of dimethviacetamide. stirred in to form a clear, homogeneous solution of 315 P.

Polyurethane k)

1000 parts of a Polyvtetramcthylenätherdiols molecular weight 1020 with 21.2 parts of N-methyl-bis (/ Mydroxypropyl) -amine. 368 parts of diphenylmethane 4,4'-diisocyanate and 346 parts of dimethylformamide are heated at 45 ° C. for 80 minutes until the NCO content of 2.12% (based on solids) is reached.

100 parts of the above NCO pre-adduct solution are in stirred a warm solution of 1.95 parts of carbodihydrazide in 226 parts of dimethylformamide and the then homogeneous, semi-viscous solution (1000 P 20 C) diluted with dimethylformamide to 23 percent by weight (530 P '20 C).

Polyurethane 1)

245 parts of the NCO Voraddtiktlösung described for Pol vuret hank (are in a finely divided suspension, prepared by introducing 5 parts of solid hydrazine acid into a solution of 2.87 parts of hydrazine hydrate in 559 parts of dimethylformamide, stirred in, whereby a homogeneous solution under CO ^ -Hntwieklung (290 P 20 C) is obtained, the viscosity of which mir-h

2

616

Addition of l!, 2 "Ϊ
470 P ansieiui.

He \ aii-l.6-dK

added to stirring, with eiiic clear solution; vnii 555 P 20 C is obtained.

Polyurethane ml

257! Fallopian tube door polyurethane k) described NC '() - pre-addict solution are in a suspension prepared by throwing in 8 parts of solid carbonic acid in a solution of 3.32 parts of ethylenediamine in 6 (K) parts of dimethylformamide, stirred in to form a viscous solution, the viscosity of which after adding 0.4 parts of He. \ an-I.6-diisoe \ ana! continues to rise to 506 P / 20 C.

Polyurethane η I

SOO parts of an adipic acid-helium andiol-1.6 2.2-dimethylpropanediol-1.3-iVI mixed polyester (diol ratio 65:35). OH number 65.9. and 98 parts of 2,2-dimethylpropanediol-1. ^; are mixed with a solution of 451 parts of diphenymethane-4,4'-diisocyanate and 339 parts of dimethylformamide at 50 ° C., the temperature rising to 88 ° C. for a short time. A reaction temperature of about 55 to 60 ° C. is maintained by cooling. After 60 minutes the NCO content of the NCO pre-adduct is 2.36% (based on solids content).

266 parts of the NCO pre-adduct are dissolved in a solution of 9.72 parts of // - semicarbazidopropionic acid hydrazidine 19 parts of water and 561 parts of dimethylformamide to form a solution of viscosity 410 P stirred in.

Polyurethane o)

800 parts of an adipic acid-ethylene glycol butanediol-1.4 mixed polyester (OH number 54.8) are combined with 35.2 parts of 1,4-ButanedioI with a solution 297 parts of diphenylmethane 4,4'-diisocyanate in 286 parts of dimethylformamide are added at 50 ° C, the reaction temperature rising briefly to 71 ° C., brought to 50 ° C. by cooling, and 30 minutes is kept at this temperature. The cloudy NCO pre-adduct mixture has an NCO content of 2.86% NCO (in the solid).

10.58 parts of carbodihydrazide are dissolved in 910 parts of dimethylformamide at 60 to 70 ° C. and mixed with 430 parts of the above NCO pre-adduct solution were stirred. The homogeneous, clear solution (180 P 20 C) rises Addition of 0.5 part of diphenyl metha1M ^ '- diisocyanate to a viscosity of 630 P.

Polyurethane p)

800 parts of an adipic acid-ethylene glycol biitanediol-1,4-mixed polyester (OH number 54.8) and 70.4 parts of 1,4-butanediol are mixed with a solution of 407 parts of diphenylmethane-4,4'-diisocyanate in 694 parts of dimethylformamide at 40.degree the reaction temperature rises to 83 C, but is quickly brought to about 50 C by cooling. After about 50 minutes at 40 to 50 ° C., a relatively viscous, cloudy NCO pre-adduct mixture is obtained which contains 2.49% NCO (based on solids) .

307 parts of the NCO pre-adduct are dissolved in a solution of 10.0 parts / f-semi-arbazidopropionic acid hydrazide

(NH ₂ - NH CONII - CI I ₂ ■ CH, · CO · NH · NH,) in 20 parts of water and 490 parts of dimethylformamide pol} urethane i |)

s 14.9 parts of carbodihydrazide are divided into 1325 parts Dissolved dimethylformamide at 70 ° C. and stirred 5 parts of the NCO pre-described in p) with stirring iidduktlösiing mixed, leaving a clear, homogeneous viscous solution (670 P 20 C) is obtained-

Polyurethane r)

By esterification of 1752 parts of adipic acid to 762 parts of bishydroxyethyl terephthalate 698 parts Äthylennlvkol is "a polyester dei

.5 OH number 77.9 established. 6 (X) parts of it become with 73.5 parts of diphenylmeihan-4,4'-diisoeyanate unc 194 parts of dimethylformamide to the NCO pre-adducl implemented. 537.5 parts of the NCO pre-adduct solution! are with a solution of 12.3 parts of carbodihydrazide in 1136 parts of dimethylformamide to one Solution of viscosity 880 P implemented.

Polyurethane s)

By esterifying 1752 parts of adipic acid.

762 parts of bishydroxyethyl terephthalate and I32S parts of hexanedioI-1.6 is a polyester OH number 67 established. 600 parts of the polyester are mixed with 157.5 parts of dipheny! Methane-4,4'-diisocyanate and 190 parts of dimethylformamide for 40 minutes

} o 55 C implemented. 535 parts of the NCO pre-adduct formed are stirred into a solution of 12.95 parts of carbodihydrazide in H42 parts of dimethylformamide to form a solution with a viscosity of 660 P.

■ "polyurethane t)

A polyester of the composition as in r) with the OH number 47 becomes 600 parts with 128 parts Diphenylmethane-4,4'-diisocyanate and 183 parts of dimethylformamide45 Minutes at 50 C to the NCO pre-adduct, 543 parts of which in a Solution of 13.24 parts of carbodihydrazide in 1139 parts Dimethylformamide is added to form a solution with a viscosity of 500 P.

Polyurethane u)

600 parts of an adipic-butanediol-M polyester with a molecular weight of 1695 are heated with 155.3 parts of diphynylmethane-4,4'-diisocyanate and 189 parts of dimethylformamide at 50 ° C. for 100 minutes until the NCO content is 2.855% (based on solids). 532 parts of the NCO pre-adduct solution are stirred with a solution of 13.15 parts of carbodihydrazide in 1139 files of dimethylformamide at 65 ° C., a homogeneous solution having a viscosity of 700 P / 20 ° C. being formed.

Polyurethane v)

1100 parts of a mixed polyester made of adipic acid

fio He.xandiol-1,6 and 2,2-dimethylpropanediol-1,3 im Molar ratio 65:35 (OH number 65.9) are mixed with 659 g of a solution of 331 parts of 4,4'-diphenylmethane diisocyanate in 373 parts of dimethylformamide, which have an NCO content after standing for 30 minutes

fts of 6.35%. 5 hours between 50 and 60 C. implemented. The NCO content of the pre-adduct is then 3.32% based on the solids.

162 parts of the above NCO pre-adduct will be

2 025 6! 6

ti

- Stirred into a solution of 362 parts of dimethylformamide and 4. (Ί files of carbodihydrazide at 50 to 60 C. The solution then has a viscosity of K55 P at 20 C.

r'olyiircthan w)

16OTeUe of the above NCO-Vontdüukt in a solution of 340 parts of dimethylformamide and Stir in 9.55 parts of pimelic acid dihydrazide at 60 to HO C. The solution has a viscosity at 20 C .. mc by S (X) P.

Polyurethane x)

150 parts of the NCO-Voradduki.es described in regulation v) are in a solution of 340 parts of dimethylformamide and 10.3 parts of Korkäuredihydia / id Introduced at 70 to Hü C. After cooling, the solution has a viscosity of 630 P at 20 C.

Polyurethane y)

158 parts of the NCO-Voraddukies described in regulation v) are in a solution of 343 parts of dimethylformamide and 11.7 parts of sebacic acid dihydrazide stirred in at 80 to 90 C. After cooling, the viscosity of the polyurethane solution is 675 P at 20 C.

Polyurethane z)

150 parts of adipic acid 1,4-butanediol polyester (molecular weight about 950) with 133 g of a Solution of 90 parts of 4,4'-diphenylmethane diisocyanate in 67 parts of dimethylformamide, which after 30 minutes Stand had an NCO content of 19.1%. 120 minutes implemented at 50 to 54 C. The NCO content of the pre-adduct is then 5.29% based on Solid matter.

212 parts of the above NCO pre-adduct are in a solution of 425 parts of dimethylformamide and 9.75 parts of carbodihydrazide, which was dissolved in 19.5 parts of hot water, stirred in at 30.degree. To 40.degree. To When the reaction is complete, the 26% solution has a viscosity of 655 P.

Polyurethane aa)

170 parts of adipic acid / 1.4-butanediol polyester (Molecular weight about 950) are mixed with 412 g of a solution of 180 parts of 4,4'-Diphcnylmethandiisocyanal in 267 parts of dimethylformamide, which, after standing for 30 minutes, has an NCO content of 13.55% had reacted at about 40 to 45 ° C. After 5 minutes, 32.3 parts are obtained within 20 minutes 1,4-Butanediol was added dropwise between 40 and 45 ° C. The NCO content of the pre-adduct is after 90 minutes at 2.73% NCO based on solids.

500 parts of the above NCO-preadduct are stirred into a solution of 1016 parts of dimethylformamide and 9.44 parts of carbodihydrazide, which was dissolved hot in 18.9 parts of water at about 30 ⁰ C. When the reaction is complete, the 20% solution has a viscosity of 175 P.

Polyurethane bb)

1000 g of an alipic acid / ethylcnglycol-butanediol mixed polymer (Molar ratio of glycols 1: 1; OH number 55.0; acid number 0.70; water content 0.01%) are with 93.0 g of 1,4-butanediol, 14.4 g of titanium dioxide (rutile) and 0.31 g of ice-cream (III) -acctylacetonate 60 ° C. and 400 g of phenylmethane - 4,4 '- diisocyanate are quickly added while stirring. the Melt is poured into shallow bowls after about 3 minutes of mixing and 15 minutes in one on - 110 C heated oven reheated, then the already solidified Poiyureihanmasst- ciunomir.cn and by granulated after cooling.

To prepare a solution, 250 g of granulated Polyurethane with a ;;, - value of 0.90 proportion-IU wise added to 75Ol 'dimethylformamide at 50 to 60 C with stirring, until after about 8 hours complete solution has occurred. The viscosity of the solution is 35 P / 20 C.

Polyurethane cc)

200 parts of an adipic acid, '!, 4-butanediol polyester (\ Mekulargewichlelwa950) are with 431 parts of a solution of 175 parts of 4,4'-diphenylmethane diisocyanate in 286.1 parts of dimethylformamide which, after standing for 30 minutes, has an NCO content of 12.8%, reacted at 40 to 50'C. After 5 minutes, the reaction temperature will be the same 38 parts of 1,4-butanediol were added dropwise over the course of 25 minutes. The solution becomes with increasing reaction time more viscous. It is gradually diluted to 26% with dimethylformamide. She owns after 24 hours a viscosity of 1260 P.

■ ^{; o} polyurethane dd)

200 parts of an adipic acid / 1,4-butanediol polyester (Molecular weight 400) v / earth with 355 parts of a solution of 200 parts of 4,4'-diphenylmethane diisocyanate in 177.2 parts of dimethylformamide which, after standing for 30 minutes, have an NCO content of 17.8% / reacted at 35 to 45 ° C. The NCO content of the pre-adduct is 5.4% NCO based on the solid substance after 190 minutes.

4c 485 parts of the above pre-adduct are in a Solution of 781 parts of dimethylformamide and 19.75 parts of carbodihydrazide in 39.5 parts of water is dissolved hot. stirred in between 30 to 35 ° C. The approximately 26% solution has a viscosity of 54 P.

Polyurethane ee)

210 parts of a 1 hour at 130 "C / 12 Torr

= 0 volatile-free polyester au; I.6-hexanediol and f-caprolactone with the OH number:

78.5 with 50.5 parts of 1,6-hexamethylene diisocyanate brought to an internal temperature of 75 to 78 ° C. with stirring and held for 20 minutes. the hot pre-adduct melt (NCO content 4.62%) is cooled down and treated with H2 parts of dimethylformamide diluted a solution with 70% solids content.

198 parts of this NCÖ pre-adduct solution are used in a 50 to 55 ° C hot solution of 7.41 parts of fto carbodihydrazide, 14.82 parts of water and 368 parts Stir in dimethylformamide as quickly as possible, if a solution of 320 P at 25 ° C. is obtained. Dci The solids content of the solution is 25%.

^{6 <i} polyurethane Π)

265 parts of a polyester of the composition as described under regulation cc) and an OH

21

/ 3

The number is 106 with 84.1 parts of 1,6-hexamethylene diisocyanate 45 minutes to 70 to 75 ° C warmed up. The NCO content of the melt is then 5.69%. After cooling to 40 to 45 C and adding 150 parts of dimethylformamide one has an NCO content of 3.94%. The viscosity of the 7 ()% pre-adduct solution is 12.3 P 25 C. Parts of the NCO pre-adduct solution are mixed with a 50 to 55 ° C. solution of 9.29 parts Carbodihydrazide. 13.94 parts of water and 375 parts of dimethylformamide were stirred. It becomes a solution of P resume at 25 C.

22nd

Polyurethane ggl

(SO parts of a polycaprolactone ester according to the example eel mil of OH number 185 are 88.2 parts I.d-Hexameihvllenendiisoevanat and 115 parts of dimethylformamide Reacted for 20 minutes at 40 to 45 ° C. The NCO content of the pre-adduct is 4.90%. Parts of the above pre-adduct are added to the solution of 371 parts of dimethylformamide. 11.7 Share Carbodüivdra / id and 23.4 parts of water at 50 ° C iimgesel / l. The resulting 25% solution possesses / l a viscosity of 216 P at 25 C.

Table I.
Properties of solid films of the polyurethanes used for microporous coagulation *)

IViwircthan

C.
d

G
H

m
η
ο
P.

r
s
t
u

V W. X

Mniliil 15 (1 ".,

Tear strength j Hnicliddiniiii !; " \ lmliil 3 (10" .ι ι ^! Kückkelirkimc

I! 3 («i" ..ι

(μ dicvi I Ι "· ιΙ 'im;.; illcvl, line iltevl

0.66

0.56
0.53
0.67
0.78
0.50
0.54
0.57
0.48
0.52
0.69
0.63
0.64
0.69
0.72
0.73
0.62
0.82
0.71
0.66
0.51
0.53
0.82

ι ".ι
480
486
511
546
628
520
586
536
58 p
566
424
653
490
529
619
603
763
681
622
515
463
474
529

285 214 203 165 103 108

81 137 105 101 414 132 250 241 170 134 103

97 131 137 150 162 410 16

14th

18 18 20 16

T)

21 20 20 19 17 18 20 18 14 20 18 18 17 16 16

St. Ι)! Ιμ ItI) T ** ("« I (O !? ■ 170 23 168 28 168 12th 163 14th 160 15th 29 15th 17th 27 27 178 17th 170 28 183 26th 169 13th 164 14th 167 11th 163 16 162 18th 165 21 165 22nd 140 23 137 51 181

The »/, - value of the viscosity ι /, =

In,.,

in hexamethylphosphoramide is within the limits of 0.7 for the above polyurethanes

until 1.5. All the melting points of the polyurethanes (measured on the Kofler bench) are above 220 C.

*) Solutions dried in a drying cabinet at 100 C to form a transparent film.

**) HDT Heat Distortion temperature measurement specification, Belgian patent 734 189. with 1.8 mg / dtex as preload and heating rate 2.1 "/ min is selected.

A2) Production of the microporous films Example 1

A 26% dimethylformamide solution of the polyurethane a) is treated with a dimethylformamide / water 60 Mixture diluted to 23% so that 1.5 percent by weight of water is contained in the total solution. The solution is stirred for 2 hours at 100 ° C. and then evenly applied to glass plates with a doctor blade applied. The films are pregelatinized at 75 ° C. and 90% relative humidity.

The films are then coagulated in water at room temperature for 30 minutes and then dried by leaving them at room temperature. If the steam gelation times f ,, sc are varied, films with an extraordinary difference in microporosity are obtained. Surface and appearance. Films with / i = 0 minutes are completely transparent, with I ₁ = still predominantly transparent, with white spots and edges, a rough surface and a strong tendency to curl. With r = 20 minutes, smooth, evenly microporous films are obtained. A smooth film with an excellent surface and a good handle is obtained with T ₁ = 30 minutes. While the quality of the surface decreases somewhat with increasing time r, the PK value reaches a

Maximum around ί.40 minutes. The readings are shown in Fig. '. Over 2 hours prolonged exposure to the hot steam atmosphere, the foils become completely transparent again and impermeable to water vapor They then resemble f ' > licn. which have been obtained by evaporating the solvent in a drying cabinet are (see Fig. I).

If one increases the Dampftenipcialui in the previous phase to 100 (at 100% relative humidity, so will the maximum of the microporosity of the films reached faster (after about 20 to 30 minutes) and after The films begin to be less permeable to steam as soon as the steam has been exposed to the steam for 1 hour or to become partially transparent.

It can be seen from the example that for a certain substance at I inwükunu \ on steam certain temperature and reuehte in each case a maximum range exists, which is the desired Microporosity provides (compare Λ b b. 11.

Comparative test I. I

Can be the same solution as (C about 22 60% relative humidity) are provided in Example I over a period of I to 120 minutes in a humid atmosphere for gelation and then moves as indicated in Example I, so erhall one only lrans _r arenle or predominantly transparent foils with a rough surface and a strong tendency to curl.

Comparative experiment 1.2

(in accordance with the German design code I 23N 206.
analogous to example I)

A 23% strength dimethylformamide solution of PoK-urcthans a) is applied evenly to a glass plate with a doctor blade, so that a film about 1.2 mm thick is formed. This film is immersed directly in water at 95 ° C. for 2 minutes and then in water at about 20 ° C. and air-dried at 60 ° C. After drying, a shrink film which is transparent and has a high curling tendency and has no microporosity is obtained and has an extremely low perniciousness (<200). "

Comparison test 1.3
(analogous to the German interpretation document 1 110 607)

A dimethylformamide solution of the polyurethane a) is evenly applied to a glass plate using a doctor blade painted in a thickness of about 1.2 mm. 90 minutes in air with 62% relative humidity Left to stand at 22 ° C. for pre-gelation and then coagulated in cold water for 3 hours and then dried in the air. The result is a coarsely structured film, which is about 80% transparent and has scattered, white islands of a somewhat microporous structure, at the edge in narrow width about 5 mm wide is also white. but also here has a partially coarse-pored structure. The foil in this form is by far insufficient for practical purposes.

Comparison test 1.4
(according to German Offenlegungsschrift 1 444 165)

A dimethylformamide solution of the polyurethane a) is applied to a glass plate about 1.2 mm with a doctor blade applied very evenly and then in a Koasjulievbad the composition 50 "η Dimelhvl-Inimamid and 50% water soaked for 20 minutes, several hours in cold water with removal ■ ties dimethylformamide * from the film coagulated and dried in animal air. It becomes a transparent drying, not microporous, strongly curling up Obtain film that has a very low Permeallonskoeflänke.

Example 2

The solution of the polyurethane b) is diluted to a solids content with aqueous dimethylformamide

■ s ν mi 23 ",, with a water content of 1.5 wt. ; nt in tier total solution. The solution will be I hour on KH) ('heated with stirring and spread on glass plates. These spreads are 3d minutes in a steam temperature of 70 C KH)%

.... relative humidity or 100 C 100% relative humidity pre-gelled, then freed from the solvent in running water for 30 minutes. 5 minutes in Immersed in methanol and then dried in warm air. Films are awarded with

2s uniform surface, high water vapor permeability wedge and for this permeability to have high strength (see Table 2).

Comparative tests 2.1

(j traversing "is transparent as in Example 2 but only moist air used instead of steam (23 C 55% relative I euchtei iir Vorgclierung. Sun strongly ge .rümpfte elastomer films with insufficient water vapor permeabilities I ¹ II ■ 10 ^s <500crhal-

u th.

Example 3

line dimethylformamide solution of the polyurethane i) is stirred for 2 hours at K) O C and then with a doctor blade evenly with a thickness of 1 mm applied to glass plates. A film is left in steam for 30 minutes at 100 V (100% relative Humidity) and for comparison another film 30 minutes at room temperature and 65% relative Pre-gelation of moisture and then coagulation in water (30 minutes) and subsequent immersion in methanol (5 minutes).

Both films show a microporous structure after drying. The compiled in Table 2 Measured values show that, with comparable water vapor permeability, the tear strength and modulus 300 of the film pregelled in accordance with the invention in the steam is considerably higher than the values of the comparative experiment (according to German interpretation 1 110 607) is what

5 = on the more even structure of the first film must be returned. Accordingly, the surface of the first film is smooth and even, while the second film has a sponge-like structure with small bubbles on the underside.

The example and the comparative test show that even with the (few) polyurethane solutions, which can be microporous coagulated with moist air at room temperature after pre-gelling the implementation according to the invention of the previous

6s tion with hot steam microporous films of improved, more uniform structure with improved surface properties and significantly improved Strengths can be achieved.

309 586/444

25th

26th

Tabel:
Conditions for making and covering microporous films

At- ■ picl

; / ικϋι / ο / in Ιΐίΐηιϋιιηΐΐ j \ oriiclior

huh

2.1 ξ b
bl
2.1 bl

I Κο ,, μιι-lalion--! bad KaW-

IM '-1 _ (ivvitTJ ί del Pl- ι ΙίίΗΐιιιμιιημπι

j Ι. >> Μΐημ j i ι ', ".' ,,

^! mini (ill

Uriich- 'module
diiliniiiiL · ¹ 30Ί ' ¹ ..

Ιμ illcM 'I "., I Ilmi; dlevi

! .S ",, | 1, ο j MiIOO j .Vl 70 ΙΟΊ"., Ί 100 0: η.16 j> | 4 ι 1.5 "., I ';, O i IhIOO ι Ό 100 ΙΟΙ)", , '' 100 0 0.13 445 |

5.0 "',, II, O! 21ι 100! 30 KIO HX)" ,. j H) (I II I 0.13 55 ') j

j 2Ii UXI
2Ii K) O

HHI! (ΧΙ ¹¹ ,, j 100 Il 'O.24S j ^ 72 ^! 7 ^Γ , 25 (>-'"., Ι 100 ο ^: 0.120 ι 40"

The hamlet of the l ^; olie according to ti ι a ν it is for ISIcili. Ι) Ιιμ.

ι "" I.

IX IS I ¹ )

PK Kf

Ii · cm tone

250 IXX) 260 IHK) 320 (XX)

2 2 ¹ KXI

Water-

tli vaccine

dtirch-

lassn ^ kcil

mg h cnr

, '1.5 22.0 22.6

I.X 1.5

Remarks

giitc obcrniichcn good l.ichlhcsliindi.jkeil

giilc surfaces bad surface structure

Example 2.1: 2.2: 2.3 3.8 to 3.9

kp

Example 3.1: 3.2 6.5 to 7.6 ₍ .

kp

Table 3
Production conditions and properties of microporous films

Example
No. 4

PoU-iiretlian

/ usiit / e / ui

IT-I ÖM1I111

b I no ΡΛΝ

h 1% PAN

Ι ". '» ΡΛΝ
I "■" PAN

% ΡΛΝ

.1 η 1 / \; N 3% ΡΛΝ b 5% ΡΛΝ 5% PAN b 10% PAN 10% PAN

Pretreatment
the IT "

I iiMint I

I ii inn
I h KKI

I h KXl
lh loo
without

2h KK)
2h HX)
without

without
without

without
without

Voruclier- j,

IIlOll ^

had 25 Cl parts ill.)! ' ¹ I.
'V' ¹ '); I fractional '■ module ι
^r V? ' dchn:.! 3 (Hl ¹¹ ,

(min C r. Il j

711 W ". Η I

KX) in the "η

7X KK) "/ ,,

101! 100 "ι,

75 KK) ^0- Ii

■ * 7 05 "Ί.

KX) KH) ¹ ! ,,

75 100%

78 ΠΚ)%

HX) 100%

76 100%
100 100%

ι
j

wedge Il in ·; dle \ |.

HH) 0 HH) Il

HH) I) HX) 0

0.16 y

Ί.13 I

0.25 y

0.27 I.

IK) 0 0.26 00 0 0.24 (X) 0 0.25 on ο 0.24 IX) 0 0.27 00.0 0.20 000 0.27 000 0.23

515 405 500 605 585

58X 500 620

605 630

635 565 6X

72

70
74
66

77
75

80
83

Stay Dim.

IX IX

13 13 14

14 14 16

17 18

10 10

Water llilllipf- PK K) " iliirch- μ liissm- ι a ■ Torr wedge
rag Ii ■ cm ' 260 (XX) 21.5 17 (X) O 8.5 21 (XX) 9.5 5,600 4.5 15,000 7.5 6 XOO 5.0 6,000 5.0 7 100 4.0 4,400 3.5 4,200 3.5 2,200 1.5

Remarks

C> r i fT der

I olic improves (becomes »dry)

Example 4

Dissolve in the polyurethane solution b) an additional 55 1, 3, 5% or 10 percent by weight (based on on the solid substance) of a polyacrylonitrile copolymer composed of 95% acrylonitrile and 5% methyl methacrylate and carries out the pre-gelation or coagulation while varying the test conditions gen (see Table 3), one obtains with increasing Additional amounts of polyacrylonitrile copolymer (PAN) reduce the water vapor permeability and an improvement in the surface and feel of the microporous layer. So from a ^ 5 Polyurethane an optimization in terms of water vapor permeability. Strength and surface properties Achieve this is neither too high. still too low a water vapor permeability he wishes. The polymer additives bring about an equalization under the steam pre-gelation conditions the microporous structure while improving the strength values of the films (results see table 3).

Example 5

In the following, a large number of different doors are used These polyurethane solutions under observance of the following »standard conditions« create m'kro porous foils carried out. The most important properties of the microporous films are communicated (see table 4).

Standardbcdiiijiiniu for the search script

The solution in dimethylformamide (about 23%) With additions of 0 to 5 percent by weight of water (based on the solution), if necessary, through to Stir the solution at 50 to 100 ° C. for 1 hour "Aged". The optionally warm (40 to 95 C) solution is applied to warmed glass plates in thicknesses from about 0.5 to 1.5 mm spread on. The "pre-adjustment" is carried out for about 30 minutes in air essentially saturated with water vapor at 75 to 100.degree. The "coagulation" of the film takes place in water at room temperature with dimethylformamide carried out from 0 to 20% (duration about 30 minutes). Hinc post-treatment of the white, microporous film is made by subsequently bathing the film in methanol (up to 30 minutes residence time). The foils are dried by lying the foils for 2 to 15 hours at room temperature, followed by a long drying at IK) C.

Of all the polyurethane solutions were under the standard conditions, but with pregelatinization in Air at room temperature and a relative humidity of 50 to 65% (! Exposure time 15 to 30 minutes) instead of the established preconditioning conditions Foils coagulated. All of these films (except for polyurethane i and /) were whole or partially transparent, severely shrunk, of poor surface and not microporous.

B e i s ρ i e 1 6

The solution of the polyurethane z) becomes a 23 percent solid by weight with aqueous dimethylformamide and a solution containing 3 percent by weight of water is added, the mixture is stirred at 50 C for 2 hours and Left for 48 hours. The solution is heated to 90 C before pouring and immediately to a hot one Glass plate (about 90 C) painted on. According to Vorgelic

tion in a steam atmosphere of 78 C and 95% relative humidity for only a short time The IOMe is then followed by a period of 1 minute Coagulated in water of 60 7 for 30 minutes, then in methanol 10 minutes! «And then dried. A microporous film with smooth, homogeneous surfaces and good tear strength is obtained (0.245 mg / dtex).

If one proceeds as above, however, the pre-gelation takes place in air at 25 C / 50% relative humidity. so you get a microporous film, but that has a rough surface and only reduced strength (0.195 mg / dtcx).

Example 7

A water-containing solution prepared as in Example 6, the polyurethane /.) Is heated to 80 "C and knife-coated onto a revolving, pre-heated steel strip (70 to 80 C) and after about 5 to 6 seconds in a steam chamber with water vapor of about 75 C After a running time of 5 minutes, the film is run into a coagulation bath at 70 ° C. The film is then introduced into a second, unheated water bath, where the remaining solvent is extracted coagulation baths is about 20 to 25 minutes. the Dimethylformamidkonzentration is maintained in bath below 5% by constant water renewal. the hot Vorgelierbades cover over the polyurethane film is maintained at 90 to 100 ⁰ C in order to avoid drop formation on the ceiling. the film web passes through After squeezing off, a methanol bath at room temperature for 10 minutes is then squeezed off again and is then turned into dried in a drying oven at 110 ° C. for 20 minutes.

A uniformly microporous film web with a smooth surface and good tear resistance is obtained.

Table 4
Manufacturing conditions and properties of microporous films

at Poly game ure No. than 5.01 a 5.02 b 5.03 C. 5.04 d 5.05 e 5.0 (p r 5.07 5.08 H 5.09 k 5.10 I. 5.1! m 5.12 η 5.13 O 5.14 η

/ usal / c / ur
PU solution

5% H, O

5% H ₂ O

5% H ₂ O
5% H, O

Pre-

i.e. indium:

the PU

Lösuny

2 h / 100
2 h / 100
211/100
2 h, KX)
2 h 100

2 h / 70

3 h / 70
2 h 100
2h / IO0
2h / KX)
2h 100
2 h / 100
2 h / KX)
2 h / 1 (X)

Yoruclicr- Coagu-
lalion bath No B-
fcsliu- fracture module Stay 3cdint! Ungcn Parts kcit strain 300% Dhg. (C. (H, O rel. Humidity) DMF) (g dlcx) (%) (mg / dtex) (%) 100.-100% 100 0 0.198 487 85 21 100.100% 100, 0 0.178 560 62 19th 100 100% 100, 0 0.225 366 166 26th 100/100% 100 0 0.132 298 - 27 KX), 100% KX) 0 0.164 414 115 70 100.100% 90 10 0.270 453 110 20th 100/1 (X)% 90 K) 0.220 526 70 17th 100 100% 100 0 0.166 464 81 21 100 100% 95 5 0.244 504 95 25th 100 100% XO .. 20 0.209 511 89 22nd KX) 100% KX). 0 0.287 5S0 86 31 90.100% 90 K) 0.330 359 204 41 100 100% 90 10 0.180 478 81 21 100 100% IOP 0 0.400 509 153 38

Water PK 10 " d; vaccination
by- nonchalance ι · cm ■ Torr mg h cm ² 17000 8.7 130,000 18.6 62,000 13.8 180,000 19.0 310000 22.6 12000 7.0 35,000 IZO 66,000 14.6 18,000 8.4 89,000 17.2 3400 2.7 25 00 1.3 110000 16.6 39 00 2.5

Wide crack strength wedge (after Graves)

(kg / cm)

2.3 3.1
3.1 / 5.1

2.4 / Z7

3.2 / 3.4
12 / 2.6

if

at
game
No. Poly
ure
than / u><ii / e / ur
i'U-LiiMing Over
plot
the IM. ¹ -
1., 1SUIlU Vurgeiicr-
bconditions ^; "., l; tliiin> had
Part,. RciH-
Te-O *; -
wedge fracture
strain Miidul
300 ",, Lead
Dhg. PK Kl "
μ
h cm torr . «·» 'J 12 (KK! Water-> water-
(Lmipf-
dirty
casualness
mg hamlet
reillfcst-
wedge (after
O ra ι es • ! .S 2.1 (C.
rel. Feuchiel
- S ",. ill.υ
I) Ml I
- IU dtCM 1%) ι πιμ dteM 31 i 140 (K) (I. h ■ crrr (kg cm ι 5.15 _μ 2h Κ ») KHI HXl ",, ΐ ",, ο.'m 44 ' 143 32 ^l 24 (KKl 14.5 5.1 7.5 5.16 4th 100 | 00 "" KHl Il 0.240 47 5 137 10; 17 (KK '. 11.5 5.17 r 5% H ₂ O 7s Ί ΊΟ HI ο 2 " ¹ O 5.25 4ii 1 Ϊ, KK) (XHi 6.5 5.IS r 5 "n ILO i h HHi "S 4 ^ "" ΊΟ | u 0.220 4 "' Ί7 S 53IKi 16.0 5.14 r 7S 4 1"., 40 III i 1. Ί H I \ "l 1 IO ^; 4 77 (Ki 3.6 5.20 N ^ P 4 1", 40 10 0.31H! 443 1117 14, S4 (KKI 4.5 2.1 2.S \ 21 S. 2h HH! "S Ί ; "" ΊΟ | ιι 0.2Hl 47 ' 4f, ! ' 72 (KKl 16.5 5.22 S. 5 "., H ₂ O lh 100 "S Ί 40 IO ο. Ι "ι ι 452 S " 14 43 (KKi 15.0 > 23 I. 2h class 7 s' j | 40 | ll 0.140 ; -ί "V. 14 6SIKO I 1.4 5.24 t 5 "" H ₂ O "5 41 40 | 0 0.220 515 S7 15 54 00 14.7 5.25 U "S 4 "" ., HI O 0.25 (1 74 Γ IMK) O 4.4 5.26 U 2h l («i 75 4 "., liXl O 0.25 ι ■ S3 I "64 00 7.4 5.27 U 5 "o H ₂ O "'S 4 IOO O '1.2''Ii 5Ti 6 p H) 20 (KKI 4.2 5.2K U 5% H ₂ O 1 h iodine "5 ') 7S 45 '· ,, H) O O 0.1 SI) 501 -5 22 50 (XKI P.5 \ 24 5% H ₂ O I h HK) ~ S 4 75 ΊΓ, ",, 40 IO 0.230 -iV Ί5. 25 36 (KK) 12.0 - 3D U 5 " _n H ₂ O 1 Ii im) ■ 'S 4 ¹ S 4 (1 "" 40 IH O. ISl) 4 "2 S 5 2s 15,000 11.0 see 31 \ 5 "" H ₂ O I Ii KHI ^ P 4 411 10 0.141) 4SI XW 27 3S (KK) 6.5 5.32 \ 5% H ₂ O I h K) O 40 IO O.220 466 102 25 S3 (KK) 11.0 p. 33 I. 2.4% HO 100 ii 0.140 Ί I 144 S 7 14.7 5.34 approx 3 " η lld 2h HUI KXI O O'4O ! ft I "> ~ 5 7.5

All foils listed in the table were white due to the "microporosity" of the film and showed good, smooth surfaces. The microporous films showed no damage or impairment of the surface after 200 (XX) buckling.

If the methanol bath aftertreatment is dispensed with, some of the previous treatments will be applied during drying microporous films are transparent at least in places (cf. 5.01. 5.06. 5.11). It also improves the After-treatment with methanol reduces the raw tone of the foils and facilitates the drying of the microporous ones Slides extraordinary.

Example p

A solution of the polyurethane aa). bb) or dd) is in optionally aqueous dimethylformamide in a solution containing 23 percent by weight diluted, stirred for 1 hour at 100 ° C. and then pricked onto preheated glass plates at 80 ° C. After different gel times (see Table 5) in hot steam or in moist air from The films are coagulated in water at 25 ° C. for 30 minutes at room temperature. 20 minutes in methanol bathed and then at 110 C for up to 5 hours: dried.

Uniformly microporous films ni are obtained; smooth surfaces. The measured values (Table 5) indicate that the water vapor permeability of the films can be controlled via the Gclierzeiten in hot steam, whereby already with superheated steam treatment from 1 to 4 minutes a significant improvement in properties compared to Gelierunti can be achieved in moist air at room temperature

Example 9

A 22 "aqueous dimethylformamide solution of the poly urethane lake). IT) or gg). which still about 3% Wassci is applied evenly to a glass plate 1.35 mm thick with a squeegee. One lets dci The film gels for a few minutes at 75 C in saturated water vapor and then leads to coagulation ii Water (15 minutes on the plate. 30 minutes oh tu plate) at room temperature. After drying from one hour at 70 to 80 ° C. the loliei show a uniformly microporous structure (measured values π Table 6).

rabclle

'olviirelhaii ( iclicr- hedinuuiiuen (mil «ί 'rl a a 30/78/95% aa 2/77/95 "'; a a I / 76/95 ", aa 10'25 / 65 ",

• il I Bnicl'dehnuny ⁽ \ lndul 100 "

Ι'Ί.Ι! One dle \ l

j, 3,

! ι ίο

ί no

'no

^ dlev) I ",. I 0.27 24f 1.14 I7X 0.14 172 O.I 1 137

I ¹ K Ιοί!
h cm * I (irr

160 (K) O
59 (K) O
40,000

5,800

Steam
1IUrChKiSMPkCH

IllL '

Ii mi '

18.4

10.5

9.5

3 y

t?

Polyurethane Gelation ReiUlesligkeil - -
Elongation at break conditional (min / ' ¹ C τ. F) ig dtex) <% l bb 30/78/95 '! i, 0.13 604 bb 4/90/95% 0.11 52S bb 10 / 25.65% 0.05 427 dd 30/78/95% 0.18 148 dd 4/90 / 95% 0.22 155 dd 10/25/65% 0.17 119

Module MKl ".,
I mg diexl

23
21
17th

145
160
160

PK

h ■ cm ■ torr

380,000
28,000
I 7,000

84,000

i 1 (M) O

I 600

Tabel example

No

7.1
7.2
7.3

Pohuvellian

ee

rr
gg

Additives to Poljurelhan

3.3% H ₂ O 2.8% H ₂ O 3.9% H ^ O

Gelling I conditions ι

! imm (Ί

3.5.75 1.5.75 1.3 75

Koagulatiiuiskul

Parts II.O I) Ml

100

100 100 KciMfcsiigkcii.

Kp cnr.
l; in; - '> across "I.

91.6 51.4
102 85
7p.9 54.9

fracture Hamlet tear strain fcsugkeii. ιKp cm. ("..I lana «across *

495
625
485

7.8 5.0

10.8 7.8

2.0 1.8

p
permeability

rr.g
Y-Ym ²

25th
9.8
6.4

11.4
6.0
0.5

Water-

steam through

liissiükeil

mg
h · cnr

4.9
5.3
6.9

• | The direction in which the film is pulled.

B. Experiments using a cationic polyurethane dispersion

B I) Manufacturing instructions for the polyurethane ureas a)

Polyurethane urea a / I

35

4470 parts (parts by weight are always given) dehydrated for 1 hour at 130 C / 12 Torr Polyester made from adipic acid and 1,4-butanediol with the The OH number is 50.2 with 674 parts of hexamethylene-1,6-diisocyanate (Molar ratio of polyester to Diisocy.inat = 1: 2) brought to an internal temperature of 89 to 9 Γ C with stirring and let it stand for 25 minutes. The hot NCO pre-adduct salt (NCO content 3.82%) is, after cooling to 55 ° C., with 2206 parts Dimethylformamide added. The NCO content of the pre-adduct solution is 2.55%.

5980 parts of the above pre-adduct solution are introduced into a solution of 173 parts of carbodihydrazide, 346 parts of water and 11,040 parts of diethylformamide at about 50 to 55 ° C., a homogeneous solution having a viscosity of 196 P 25 c "at 24.9% strength The properties of the elastomer substance (measured on approximately 0.2 mm thick films, which are obtained by knife-coating the solution onto glass plates and evaporating the solvent at 100.degree. C.) are listed in Table I. The films show excellent resistance to yellowing and mechanical degradation.

Polyurethane urea a / 2

.'l440Teilc of a described in regulation al Polyester with an OH number of 52.2 and 47.6 parts of N-methyldialhanolamine (molar ratio of polyester to <>? Aminol = 0.8: 0.2) are mixed with 952 parts of Diphcnylmc (han-4,4'-diisocyanate and 2550 parts dimethylformamide at 30 "C for 15 minutes.

3880 parts of this NCO pre-adduct solution (NCO content 1.49%) are heated to 55.degree Solution of 70.6 parts of carbodihydrazide. 141 parts water and 4070 parts dimethylformamide stirs. The 24.6% iue solution has a viscosity of 190 P 25 C.

Polyurethane urea a / 3

3930 parts of a polyester of adipic acid and dietylene glycol with an OH number of 42.9 are stirred at 60 ° C. with 7 parts of a 35% strength solution of SO2 in dioxane for 15 minutes and then freed from volatile constituents at 12 torr 120 ° C. for 30 minutes . The polycarbonate pretreated in this way is heated to 35 to 40 ° C. for 15 minutes with 750 parts of diphenylmethun-4,4'-diisocyana and 2010 parts of dimethylformamide. 4050 parts of the NCO pre-adduct solution (NCO content 1.70%) are carbodihydrazide with 76 parts. dissolved in 152 parts of water and 7272 parts of dimethylformamide, converted to a clear solution with a viscosity of 162 P / 25 ° C. Fesrstoff _E .: content 25.2%.

Polyurethane urea a / 4

3940 parts of a mixed polyester of adipic acid and ethylene glycol treated according to regulation a / 2 I.4-butanediol (molar ratio I: I (mild OH number 5: be with 640 parts of hexamethylene-1.ö-diisocyana Reacted for 30 minutes at 92 ° C., cooled and mixed with 1,960 parts of dimethylformamide to give the NCO pre-adduct solution (2.1% NCO) diluted.

1990 parts of this solution are added to the mixture from 44.7 parts of carbidohydrazide. 67.1 parts watct and stirred in 3678 parts of dimethylformamide. The 25.1% solution has a viscosity before 276 P 25 C.

Polvurelhanharnsioif a 5

72 (ΗίParts of a polyester au-> Adipic acid and 1,4-butanediol (OH number 62.4 i have 40 minutes at S5 C long rr.it 1280 parts hexamethylene, 6-diiso- s l- \ anat implemented. The melt cooled to 60 ° C is stirred with 3568 parts of dimethylformamide.

3950 parts of the NCO pre-adduct solution give 12.29 ⁰ O NCO) with 105.4 parts of carbodihydrazide. dissolved in 210 parts of water and 7304 parts of dimethylformamide, i "a solution with a viscosity of 157 P. 25 C. Solids content 24.3%.

Polyurethane urea a 6

450 parts of the polyester described in regulation a 5 are mixed with 1253 parts of diphenylmethane diisocyanal and 2477 parts of dimethylformamide for 10 minutes at 40 C c (AÜrmt.

6250 parts of the NCO pre-adduct solution (NCO content 2.28%) are added to the solution of 161.3 parts; <j Carbodihydrazide. 322.6 parts of water and 10,966 parts Dimethylformamide added to form a solution of 225 P (25.4% solids !.

Polyurethane urea a 7

1500 parts of the polyester from regulation a 5 with the OH number 66.7 and 25.9 parts of N-methyldiethanolamine are combined with '"" ^ parts of diphenylmethane diisocyanate reacted in 2280 parts of dimethylformamide at 25 C. After 10 minutes the NCO is w Content of the pre-adduct solution 1.23%.

In a solution of 82.5 parts of carbodihydrazide. 1.65 parts of water and 4080 parts of dimethylformamide are 3998 parts of the above NCO pre-adduct solution stirred in, a solution (25%) with a: o Viscosity of 143 P 25 C arises.

Polyurethane urea a 8

4160 parts of a Pohester from adipic acid and Diethylene glycol with an OH number of 54.0 are given with -p 673 parts of hydroxamethylene-l.o-diisocyanate at 92 ° C Reacted for 25 minutes. After cooling the melt to 60 ° C., 2075 parts of dimethylformamide are added close.

3980 parts of this "NCO pre-adduct (2.24% NCO) are with a solution of 107.6 parts of carbodihydrazide, 215.2 parts of water and 7118 parts of dimethylformamide converted to a solution of 133 P 25 C. The solids content of the solution is entrusted

24 9% "

Polyurethane urea a 9

5000 parts of an adipic acid, ethylene glycol-butanediol-1.4 mixed polyester (Molar ratio of glycols I: 1) with an OH number of 57.2 are 1205 parts Diphynylmethane-4,4'-diisocyanate and 2650 parts of dimethylformamide offset. The temperature is maintained at 40 ° C. during the 55-minute stirring. The NCO pre-adduct solution has an NCO content of 2.06%.

2050 parts of this NCO pre-adduct become a solution of 45 parts of carbodihydrazide and 90 parts Added water and 3640 parts of dimethylformamide. The solution obtained has a viscosity of 330 P / 25 C and a solids content of 25.1%.

Polyurethane urea a / 10

3400 parts of a mixed polyester of adipic acid and I.6-Hcxandiol- treated according to regulation a, I

-i?

('S 2.2-Diineih \ l |> r.jparKÜol-U (Molverhiiimis der CiIykolnuschuna Λ5: 35) with the OH / ^ ihl on be mn KK) I share D: phenylmei!: Uruiii * !! cyan <ii in 1884 Ieilen implemented dimethylformamide for 40 minutes at Ü5 C to an NCO content of 2.38%.

4030 parts of NCO pre-adduct react with 109.6 parts Carbodihydrazide, 219.2 parts of water and 7312 parts of dimethylformamide to form a cool solution from 272 P to 25 C to 25.2% solids.

Poiyureihanharnsloff a /! I.

2K) 0 parts of a polyester made from caprolactone and 1,6-hexanediol with a molecular weight of 1410 are at 74 to 76 C mn 505 parts of hexamethylene diisoc> anat implemented for 35 minutes. After cooling and adding 1120 parts of dimethylformamide one an NCO-Voraddukilösung with 3.1% NCO.

1980 Parts of this NCO pre-adduct are in di · .solution of 71.5 parts of carbodihydrazide, 107.3 parts of water and 3721 parts of dimethylformamide are stirred in The viscosity of the resulting homogeneous solution is 1X3 P / 25 C (24.9% solids).

Polyurethane urine a / l 2

2640 parts an-i as described in regulation a / 11 Polycaprolactone esters with an OH number of 107.5 are mixed with 1252 parts of diphenylmethane diisocyanai in 1680 parts of dimethylformamide for 10 minutes 35 to 40 C implemented.

1960 parts of this NCO pre-adduct solution (3.41 "" NCO) are in 80.4 parts of carbodihydrazide. 160.8 parts of water and 3641 parts of dimethylformamide are stirred in to form a solution of 160 P / 25 C (24.7% solids).

Polyurethane urea a / l 3

4120 parts of an AdipinsäuR-Hcxandiol-Polyeslers with the OH number 136 are at 30 to 35 ° C with 2,210 parts of diphenylmethane diisocyanate were stirred in 6330 parts of dimethylformamide. After 10 minutes the NCO content of the solution is 2.15%.

To 152 parts of carbodihydrazide in 304 parts of water and 6134 parts of dimethylformamide are 5920 parts of the NCO pre-adduct solution with stirring admitted. The viscosity of the clear solution increases within a few minutes to 232P / 25 ° C (24.8% Solid).

Polyurethane urea a / 14

4120 parts of the polyester from regulation a / 13 are advanced in 2025 parts of dimethylformamide with 625 parts of diphenylmethane diisocyanate. After 10 minutes stirring at 30 to 40 ⁰ C, the NCO Gehall goes to 0. In this solution 74,5Teile N-methyldiethanolamine, 1495 parts of diphenylmethane diisocyanate and 4110 parts of dimethylformamide are stirred. After 12 minutes the NCO content is 1.75%.

6030 parts of this NCO pre-adduct solution are added to the 124-part solution, which has been heated to 55.degree Carbodihydrazide. 248 parts of water and 6228 parts of dimethylformamide are stirred in, a solution with the viscosity of I86P / 25 ° C arises (25.1% solids).

Polyurethane urea a / l 5

1800 parts of a polyester made from caprolactone and 1,6-hexanediol with a molecular weight of 600

are reacted at 65 C for 8 minutes with ¹ JhO parts of hexunylethylene - 1,6 - dÜÄoeyanui. 11 SO parts of dimethylformamide are added to the melt. The NCO-Oehiili of the Voraddukles bcirimf 49Wi

199 parts of this pre-adduct solution are stirred into parts of carhodihydrazide dissolved in 234 parts of water and 37 parts of dimethylformamide. The oil viscosity is 216 P / 25 ¹ C, the solid content is 25%.

Table 7
Properties of polyurethane urea solutions and foils

a I
λ 2
; ι 3
a 4
a 5
a / 6
a. 7th
a 8
a 9
a / 10
a, Il
a / 12
a 13
a / 14
a / 15

"ι. NC O im
NCO precedent

2.55

1.49

1.70

2.10

2.29

2.28

i, 23

2.24

2.06

2.38

3.1

3.41

2.15

1.75

4.93

j LoMinu in P 25 C

196 190

162 276 157 .'-. 25 143 133 330 272 183 160 232 186 216 leslstnlTueliall
24.9

24.6

25.2
25.1
24.3
25.4
25.0
24.9
25.1
25.2
24.9
24.7
24.8
25.1
25.0

n ky cm
540
565
570
545
515
575
520
460
550
545
598
570
558
755
610

Exam university! on ClasHimerfilms on Slabprohen according to DIN 53 MH

¹ Weilcrrcilifcsliiikcil in kj: cm

Elongation at break
in "<>

905
890
9? .O
920
890
860
875
1085
855
795
620
582
555
560

58.0 69.0 62.0 56.0 74.4 81.7 68.5 54.2 47.2 42.6 64.0 52.1 41.1 36.7 39.4

Manufacturing instructions for the cationic polyurethanes b

Cationic polyurethane b / 1

1000 parts of one made from phthalic acid, adipic acid and Ethylene glycol (molar ratio 1: 1: 2.2) produced Polyester with an OH number of 62 with a water content of less than 0.1% is mixed with 257 parts of tolylene diisocyanal (Isomer mixtures 65:35) reacted at 70 ° C. for 120 minutes. To the tough Voradduki that has been preserved are successively 840 parts of dimethylformamide and 107 parts of N-methyldiethanolamine and Stirred at 50 ° C. until the viscosity is 60 P. A solution of 6.5 parts is then added one after the other Dibutylamine in 60 parts of dimethylformamide and a solution of 50 parts of 1,3-dimethyl-4,6-bis-chloromethylbenzene in 193 parts of dimethylformamide are added. The mixture is stirred at 50 ° C. until a viscosity of 45 P is reached is. A solution of 29 parts of phosphoric acid in 120 parts of water is then added one after the other, 1065 parts of dimethylformamide and 1300 parts of water b-'i 50'C were added. After cooling down, you get a 28.5% white dispersion.

Canonical polyurethane b / 4

The procedure is as in regulation b / 1, but using 33 parts of 2,5-dichloroenzoyl chloride instead of bischloromethylbenzene. After cooling, a bluish shimmering dispersion is obtained. which is 28.5%.

Cationic polyurethane b / 5

Proceed as in regulation b / 1. but using 30 parts of benzyl chloride in place des! .. VDimethylAo-bis-chloromethylbenzene and receives a 28.5% dispersion of the corresponding polyurethane.

Cationic polyurethane b / 6

The procedure is as in regulation b / 1, but using 23 parts of dimethyl sulfate. It results a 28.4% opaque polyurethane solution.

Cationic polyurethane b / 7

Cationic polyurethane b / 2 _{Map performs like} regulation b / 1, but below

The procedure is as in procedure b / 1, but using 30 parts of terephthalic acid dichloride

Use of 48 parts of acetic acid in place of the 60 in place of the K.l-Dimethyl ^ o-bis-chloromethylbenzene

Phosphoric acid. The 28.5% dispersion obtained is an opaque, viscous, 28.5% solution

is coarse. of polyurethane.

Canonical polyurethane b / 3

Proceed as described in regulation b / 1. but using before 87 parts conc. Hydrochloric acid. A 28.5% strength, opaque, viscous polyurethane liquid is obtained.

Cationic polyurethane b / 8

in regulation b / 1, but instead of the 1,3-dimethyl

One proceeds as
Phthalic acid dichloride
4.6-bis-chloromethylbenzene is used. It results

a less viscous, opaque solution of the polyurethane than in b / 7.

Cationic polyurethane b / 9 S

The procedure is as in procedure b / 1, but using 30 parts of 1,4-dichloromethylbenzene instead of the l ^ -dimelhyl- ^ o-bis-chloromethylbenzene. A thin, 28.5% strength dispersion is obtained.

B2) Manufacture of microporous films

Example 10

400 parts by weight of the solution of the Polyurcthanharn.noffs according to regulation a / 2 in dimethylformamide, which is 24.6%, with a solution of 38.4 parts of the canonical polyurethane solution according to regulation b / 1, with a further 7.6 parts of dimethylformamide are added, stirred intensively at room temperature. The mixture is 22% and has a viscosity of 116 P / 25 "C, the water content is 3.6%.

200 parts by weight of this solution are deaerated in vacuo and then painted with a doctor blade on a 460 cm ² glass plate in a 1.3 mm thick layer. This is then placed in a 90 "C box filled with relaxed steam and left in the steam atmosphere for 5 minutes, after which the solution has gelled. The plate is then placed in a water bath, where the dimethylformamide is washed out The porous film is peeled off the base after 15 minutes, left in the water bath for a further 30 minutes and then squeezed five times and soaked again with water in between. After the fifth squeezing, the smooth film is dried at 60 ° C. in flowing air. It has a water vapor permeability (according to I UP 15. "Das Leder". 1961, pp. 86 to 8H) of 16.1 mg / cm ² .

Example 11

300 parts of a 25.1% solution of the polyurethaneurea a / 9 in dimethylformamide are intensively mixed with 46.6 parts of a cationic polyurethane solution in dimethylformamide (28.5% strength according to instructions b, I with 56 parts of dimethylformamide. The solution is 22% solids and 4.5% in water. The viscosity is 214 P / 25 "C. The solution is slowly stirred for 1 hour at 70 C, degassed in vacuo and, as shown in Example 10, knife-coated on. The applied solution is 2 '/ _{Left in the steam atmosphere for 2} minutes and then treated further in a water bath as in Example I. The film produced in this way has a water vapor permeability of 18.9 mg / cm ² h.

Example 12

In each case 300 parts of the polyurethane urea solution are used 12 (in dimethylformamide, 24.7%) with the amounts of polyurethane urea given in Table 8 b / 1 and the necessary parts of dimethylformamide to obtain a 22% solution, intensive mixed at room temperature. The samples, as described in Example 10, on a glass plate in a more uniform manner Layer applied, in the steam box (90 C. 100% rel. Humidity) for the specified in the table Zeil treated and then in a water bath 7.11 End treats. After drying, the porous films have the properties listed.

Weight sver-
envelope of
PU after
script a.'l 2: b / 1 viscosity
in P / 25 80:20 185 85:15 172 90:10 158 95: 5 139 98: 2 128

Concentration of
solution

22nd
22nd
22nd
22nd
22nd

Water content

6.7
6.1
5.0
3.97

3.2

Table (example 12)

Water vapor permeability kit

(mg.cm-h)

23.3 19.1 16.4 12.1 9.8 gel time
(Mini

0.5
0.7
0.8

1.3
2.0

test

Tear resistance
(kp. cm ')

51
59
66
82
94

the microporous l-'olicn Continue reading fracture strength strain (kp / cm) (%) 5.0 395 6.1 410 6.7 442 8.0 430 9.4 580

Example 13

400 parts of a 24.3% solution of the polyurethaneurea a / 5 in dimethylformamide are used with 38 parts of a cationic polyurethane solution in dimethylformamide according to regulation b / 1 (ratio a: b = 90:10), 53 parts of dimethylformamide and with increasing Quantities (0.5 to 5%, based on the solids; Table 9) polyacrylonitrile added. The approximately 22% solutions are degassed and after

60 method specified in Example 1, 5 minutes in the steam atmosphere (90 ⁰ C; 100% re humidity) and then treated in water. The micro-porous films show a decrease in water vapor permeability with increasing amounts of polyacrylonitrile, but an improvement in handle and surface as well as an increase in the strength value. The polymer additives thus enable optimization with regard to water vapor permeability and surface.

40

Table 9
Comparison of the properties of microporous films with PAN additives according to Example 13

'ilytirclhan- / -usiit / c / ur Vorj; elieriini! N- KcilMcstigkcil Briii hdchnunp Weilerrciß- Water vaccination stibstan / I'U-l.iisunp Bcdingunpcn acuity permeability (C r. Γ.) (kp curl I "_ · ..! lkp cm) (mg / cnrh) a / 5 b / l no PAN 90/100% 53 500 10.5 19.8 a / 5 b / 1 0.5% PAN 90/100% 66 530 14.7 15.2 a / 5 b / l 1.0% PAN 90/100% 95 455 10.7 9.7 a / 5 b / l 1.5% PAN 90/100% 106 480 14.1 6.4 a / 5 b / l 2.0% PAN 90/100% 98 525 10.2 5.8 a / 5 b / l 3.0% PAN 90/100% 115 380 16.5 2.9 a / 5 b / l 4.0% PAN 90/100% 109 545 13.9 4.2 a / 5 b / l 5.0% PAN 90/100% 112 575 9.4 3.8

Example 14

The solution of the polyurethane urea a / 10 is mixed with the cationic polyurethane solution b / l (a: b = 9: l) and further dimethylformamide to a solution with a solids content of 22% and as a water content of 5.2%. The solution is poured out and pierced onto glass plates. Man treated this 10 minutes in a steam atmosphere of 80 "C / 100% relative humidity and rinses the dimethylformamide afterwards with water. The film is then immersed in methanol and in warm air dried. The films are characterized by good surfaces, water vapor permeability values and Strengths.

Example 15

In accordance with Example 10, the polyurethane urea solutions given in Table 10 below are used mixed with the specified kaiionischen polyurethane dispersions and with dimethylformamide diluted to the concentration of 22%. These solutions are knife-coated onto glass plates and exposed to the steam atmosphere. After the specified times they will be as in Example 1 in V / ater treated further. After drying, the water vapor listed in Table 10 results permeability of the foils.

Tabel

PoK urinary urine solution and regulations

a / l

a.i.i a / 4 a / 6 a / 7 a / 7 a / 7 a / 11 a / 13 a / 14 a / 15 a / 15

Cation. relationship water Gclicr- Poly-
urcthao PU a: b salary / cil before font b (%) (Min.) 90:10 4.0 10 b / l 90:10 3.3 15th b / l 90:10 3.2 5 b / l 90:10 3.8 4th b / l 90:10 4.0 3 b / 2 90:10 4.0 3 b / 9 90:10 4.0 5 b / 7 90:10 3.8 3 b / 2 90:10 4.4 10 b / 6 90:10 4.0 8th b / 9 90:10 5.6 2 b / 4 90:10 5.6 2.5 b / 5

Water

steam-

by-

casual kit

the l'olicr

(mg / hcnr

14.8

18.3

For this 1 Bktt drawings

309586 /

Claims (4)

Patent claims: 1. Stirring to produce microporous fleece structures from polyurethanes by pretreating thin layers of Polyurethaniösuuaeii. optionally with a flavorful cationic egg Polyurethane dispersion are mixed in a glowing atmosphere at elevated temperature. Coagulation of the layers in water or aqueous Fäiloä'dern ic with removal of the majority of the polyurethane solvent and subsequent drying, characterized in that the thin Layer of the polyurethane solution in a water vapor atmosphere with a relative humidity of min- is at least 50% exposed at temperatures of at least 65 C for 0.1 to 60 minutes, after which Coagulation of the microporous PoK urethane, if necessary with an aliphatic alcohol. 0.2 to Treated for 30 minutes and then dried: o is. 2. The method according to claim! characterized, that one has a water vapor aimosphere with a relative humidity of 80 to 100 "η and a temperature of 75 to 100 C for 0.1 to 30 minutes. 3. The method according to claim 1, characterized. d _u 3 one uses saturated steam at the boiling point of the water. 4. The method according to claim 1 to 3. characterized characterized in that the! "ismittelhaltigen polyurethanes or polyurethane mixtures continuous process on a manufacturing scale applies to a base, by a Treatment room with a humidity of at least 50% at a temperature above 65 C with a dwell time of 0.1 to 30 minutes, then the majority of the solvent is removed in permanent coagulation baths and optionally after squeezing off and after passing through a methanol bath with a Dwell time of 0.2 to 30 minutes in heated air dries.