DE2025616C3 - Process for the production of microporous sheet-like structures by coagulating polyurethane solutions - Google Patents

Description

45

It is known, water-vapor-permeable sheet-like structures or coatings made from solutions of polyurethanes {e.g. B. dimethylformamide) by coagulation in non-dissolution riddles (z. B. water) after a Series of processes to produce the desired, microporous structure of the polymer should be achieved by adhering to very specific> md specified conditions during coagulation. If the special conditions are not complied with, macropores can easily arise on the one hand, i. i.e., coarse, with Holes in the film that are visible to the naked eye, 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.

The use of solutions of polyurethanes or polyurethane ureas in highly polar solvents, such as dimethylformamide or dimethylacetamide, (possibly with the use of other Polymers, such as polyvinyl chloride or polyacrylonitrile) for the production of films, coatings on fabrics or as a binder for nonwovens with removal of the solvent by treatment (e.g. dipping) with water, glycerine or other liquids that are miscible with the aforementioned highly polar solvents but are incompatible with the polyurethanes, is already described in German patent specification 888 766. There is already the co-use common solvents (which are nonsolvents for the polyurethane), e.g. B. methylene chloride, Acetone or benzene

In a number of later patents special process steps are given in order to deal with more or less improved security to arrive at the desired microporous structure. This is how in German patent 1 110607 for coagulation of polyether-based polyurethanes, hygroscopic polyurethane solutions (as Solvent is used for. B. dimethylformamide) the action of a steam-containing, optionally exposed to a circulating atmosphere, which has a relative humidity of 15 to 100% at a The temperature of the dry thermometer is from 10 to 38 C. By absorbing the water due to the hygroscopic solvent, the surface of the polyurethane becomes more or less less pronounced, probably with preforming of the microporous structure. When inserting The pre-poured film or coatings in water become the hygroscopic solvent with coagulation completely removed from the film. If the pre-gelation is omitted by the action of the above specified humid atmosphere, then one obtains mostly transparent, non-permeable foils or coarse-pored, inhomogeneous films which are unusable for the intended purpose.

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

The German Offenlegungsschrift 1 444 165 specifies a further method, according to which, without pre-gelation, "" - by direct coagulation in a mixture -.m non-solvent and solvent] (e.g. dim>.;H;!"Ormamid / H ₂ O 10:90 to 95: 5) microporous ί -. κ ;? should receive.

According to another variant, which is described in Belgian patent specification 624 250, sit! so much nonsolvent is added to the polyurethane solution that the gel of the polymer can be separated off and First this gel spreads onto the substrate and coagulates in non-solvent (water) to form a microporous structure.

In this last mode of operation, it is technically difficult to separate the gel and combine it to process homogeneous coating. The mode of operation according to German Offenlegungsschrift 1 444 165 requires changes longer coagulation times, especially for baths with a lot of solvent, because the polyurethane only slowly coagulates. So the capacity of a given production facility will be greatly reduced set. You can also use this procedure

Microporous structures only with little certainty and apparently on selected polyurethane compositions can be obtained to a limited extent.

When working according to German Offenlegungsschrift 1444163, it is difficult to get the right amount of Take nonsolvents for the preparation of the colloidal dispersions. The process uses raw materials in an instable state, because the properties 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 Auslegeschrift 1 110 607 requires an _{atmosphere conditioned in terms of humidity exactly 1S} and a long exposure time in this humid atmosphere. The results are, however, hardly reproducible. Obviously, only polyether urethanes can be processed. Here, too, a relatively low productivity is achieved with a low level of security and application range.

According to the proposal of the German Offenlegungsschrift 1803021 a dry or wet stream of gas with a certain flow velocity over a surface fastener placed painted layer of a ₂ $ polyurethane solution acts formed a dense, gelled layer on the surface of the solution up by moisture or by evaporation of the solvent at the surface. It is then coagulated in water, for example. As will be explained in detail, it is expedient and desirable that the temperatures do not exceed 50.degree. C., preferably not above 30.degree.

In German Auslegeschrift 1 238 206 it is stated that direct coagulation of elastomers then leads to microporous structures if one is in baths which are close to the boiling point the bath liquid are heated, e.g. B. coagulated in hot water 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 quaternary 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.

According to this method, after treating the painted polyurethane solutions with moist Air and subsequent coagulation in water or aqueous solvent mixtures permeable to water vapor Polyurethane top layers are much safer than produced in the previously described process will.

When pretreating with moist air, residence times are necessary in this procedure

a) when adding commercially available tanning agents to the ^S5 coagulable polyurethane solution using 10 to 30 percent by weight of cationic polyurethane dispersion, not less than 10 minutes,

b) in the aftertreatment of the coagulated polyurethane cover layers in aqueous neutralized tannin solutions not for less than 20 minutes and

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

The object of the invention is an economical process for the production of microporous polyurethane top layers, without providing these complex measures and without additional chemical auxiliaries, which are carried out continuously can.

This process delivers with increased production reliability and, in particular, increased production speed and improved microporous planar structures with little expenditure on equipment, whereby Advantageously, the use of the cationic polyurethane dispersion can also be dispensed with.

The invention relates to a process for the production of microporous sheet structures from polyurethanes by pretreating thin layers of polyurethane solutions, optionally with a aqueous cationic polyurethane dispersion are mixed, in a moist atmosphere at increased Temperature, coagulation of the layers in water or aqueous precipitation baths with removal of the main amount 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 exposed to at least 50% at temperatures of at least 65 C for 0.1 to 60 minutes, after which Coagulation of the microporous polyurethane, optionally with an aliphatic alcohol, 0.2 to Treated for 30 minutes and then dried.

Solvent for polyurethane, which can be used for carrying out the method of the invention are preferably highly polar hygroscopic water-soluble organic solvent having amide, urea or Sulfoxydgruppen, particularly preferably with boiling points above 130 ⁰ C. It must in water or aqueous coagulation baths be soluble . For example, dimethylformamide, dimethylacetamide, tetramethylurea, dimethylsulfoxide, diethylformamide, formylmorpholine, hexamethylphosphoramide or mixtures thereof are suitable. In the following, these solvents are understood as “solvents” or “solvents”.

These "solvents" can also be "nonsolvents" or "non-dissolvers" may be mixed in. Liquids are to be understood by this, which the Polyurethanes do not dissolve (and preferably swell only slightly) or are inert to polyurethanes. The preferred nonsolvent is water. But there are also z. B. 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, can be used.

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 In special cases, pure alcohol is also used, preferably made from aliphatic alcohols, such as Methanol or ethanol. Mixtures of water and a "solvent" are also suitable according to the definition given above.

It was surprising that so at high temperatures and intense exposure to concentrated Water vapor a safe, even and fine-pored pre-gelation is achieved, which with considerably broader process security than with the previously described process too well microporous coagulate Leads to flat structures with a good surface. The previous methods used relatively low water vapor pressures (e.g. German interpretation 1110067

at 10 to 38 ° C and 15 to 100% relative humidity, corresponding to a maximum of about 50 Torr) and describe it as desirable that the temperature is not higher than 50 ⁰ C, preferably not higher than 30 ° C (see. German Auslegeschrift 1 803021, p. 6/7), if the pre-gelation of the solution is carried out in a flat spread.

The water vapor atmosphere for performing the method according to the invention should be at least 50%, preferably 80 to 100% relative humidity at temperatures above 65 ° C, preferably 75 to 100 ⁰ C, included. It is most expedient to work in the specified temperature range with a steam atmosphere which is as saturated as possible, for example with saturated steam or steam atmosphere over boiling 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 prior to contact with the painted 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.

Forms when exposed to the concentrated water vapor atmosphere at high temperatures A gelled polyurethane layer forms on the surface of the polyurethane solution or mixture in a very short time which then controls the further coagulation of the solution with the formation of micropores. Therefore, in general, the outermost layer of the resulting microporous film is somewhat denser than that Inner.

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

If one heats in dry air at about 80 to 100 ~ C the 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 Pre-gel heated polyurethane solution over a container with hot or boiling water in a closed room (discontinuous operation). You can also use saturated or superheated steam in a room of the appropriate temperature initiate in which the solution to be gelled is located. No condensation drops are allowed here fall on the gelling polyurethane. This can be done by appropriate design of the ceiling of the Gelierraumes or z. B. can be prevented by heating the ceiling and / or the coagulation pad.

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 pourers, then optionally; for equalization of the applied solution a short distance without the action of steam or one of ίο subject the underside to a vacuum (for direct coating and impregnation of textiles, such as woven, knitted or non-woven or felt-like materials) and then through the hot Lead treatment room containing water vapor. If necessary, the carrier material can also be used be heated.

Ah coagulating liquids, water or aqueous solutions of the polyurethane solvent come in Consideration, e.g. B. water, dimethylformamide, mixtures up to a mixing ratio of 1: 1. One can Provide a coagulating bath or several coagulating baths of different compositions one after the other. The bath temperatures are preferably from 20 to 35 ° C .; however, it can also be higher and lower Temperatures used or if several baths are used, temperatures and concentrations varied will.

If a concentrated alcohol solution, preferably methanol, is used as the final wash bath, see the microporous structure is stabilized and the subsequent drying is made much easier. The drying can be done in conventional hot air dryers after squeezing off excess liquid will.

Polyurethanes suitable for producing the solutions are, in particular, rubber-like polyurethanes. In principle, all polyurethanes can be used, but their tendency to form the microporous structure is different. The formation of microporosity can be achieved by adding cationic Polyurethane dispersions make the polyurethane solution much easier, but it occasionally increases a deterioration in the mechanical strength of the microporous film is accepted. The crowd more cationic Polyurethane dispersion should generally not exceed 35 percent by weight. Preferred one takes from 0.5 to 20 percent by weight and particularly advantageously from 0.5 to 10 percent by weight. Percentages each refer to the solid in the polyurethane solution and the dispersion.

The cationic polyurethane dispersions are particularly effective in the continuous production of the microporous ones Flat structures regulating and stabilizing when treated with steam and with dei subsequent coagulation. You thus improve di (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 tannins, carboxymethyl cellulose, PoIj alkyl (meth) acrylates. Emulsifiers, optical brighteners, antioxidants, special light stabilizers, w N.N-dialkyl hydrazides. crosslinking substances Zen. like paraformaldehyde. Meiaminhexamethylci ether or other formaldehyde derivatives, polyisocyanate; nate. Quaternizing agents or polyaziridinhari

substances and dyes, more appropriate insoluble ones

may ö ^ speziel.er innuence the KoagulierbarkeH of S by adding non-

their isocyanate-reactive ^^ _{bound to} nitrogen atoms

lähieen polyurethane systems, au

^^ _this chain extension

⁸ d 2 reaction preferred in hoc ^ j

_{Lösungsmiudn,} ü _with e.nem boiling point

^1S

should be 9% in general

suitable, which however al Ic ow ^ _{En k} i _o gruppierungenthaUe ^ vgLUl 1 m ^ ^ _{&? 3 Ws} sation ^

^ ^rteC Γϊ, for example, Polyurethane 40 Hexand ο

and diols or amines such as _molecular weights are _{also suitable ;} Special

Polyurethanharn _Äl herdiolen.die given

Solvents work

«En.

in highly polar

diisocyanate may be mentioned

Expected 1 270 ^ essence Manufacture will be hoch ^ W ^ JijJ _ändi

with bifunctional compounds, the mmac

4. ^ _{Λ y} idiphenylm

_is ocyanate, 2J-WJ «^^ _{Di hen}

_{409646/2 |}

2 9

or halogen substitution products, dimeric toluene-2,4-diisocyanate, Bis (3-methyl-4-isocyanatophenyl) urea or naphthylene-1,5-diisocyanate. Aliphatic diisocyanates, such as hexamethylene diisocyanate, Cyclohexane - 1,4-diisocyanate, dicyclohexylmethane-4,4 ' - diisocyanate, 1 - isocyanato - 3 - isocyanatomethyl-3,5,5 - trimethylcyclohexane or 2,2,4 - trimethylhexane-1,6-diisocyanate, can be used and produce very little discolouring products when exposed to light.

Diphenylmethane-4,4'-diisocyanate, the isomeric tolylene diisocyanates, p-xylylene diisocyanate, as well as - optionally partially hexamethylene diisocyanate or dicyclohexylmethane-4,4'-diisocyanate, used.

The higher molecular weight polyhydric compounds are mixed with the diisocyanates in about a molar ratio of 1: 1.25 to 1: 4.0, optionally in several stages in the melt or in solvents inert to isocyanates, such as tetrahydrofuran, dioxane or chlorobenzene or dimethylformamide, at temperatures of about 20 to 13O ⁰ C, preferably 40 to 100 C. implemented.

Reaction times are kept such that an essentially linear pre-adduct with terminal NCO groups is obtained, which in the implementation with approximately equivalent amounts of bifunctional Chain extenders are a substantially linear elastomeric which is soluble in polar solvents Polyurethane or a polyurethane urea results.

It can be used together with higher molecular weight polyhydroxy compounds and low molecular weight diols (molecular weight preferably below 250), z. B. ethylene glycol, 1,4-butanediol, bis-N, N - (/? - hydroxyäthyI) -methylamine. Bis - N, N - (ß - hydroxypropyl) - methylamine, N.N'-bis-hydroxyethylpiperazine or hydroquinone-bis (/ S-hydroxyethyl ether) can also be used. The amount of low molecular weight diols can be, for. B. be dimensioned so that 0.1 to 3 mol OH groups of the low molecular weight diol are present per mole of OH groups of the higher molecular weight polyhydroxyl compound. Diols with tertiary nitrogen increase the colorability, improve the light resistance and create the point of attack for further after-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 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, have and can optionally be used in a mixture or stepwise reaction will. In addition to water, there are for example ethylenediamine, 1,2- or 1,3-propylenediamine, 1.4 - tetramethylene diamine, ί, 6 - hexamethylene diamine.

2,2,4 - trimethylhexanediamine - 1,6, 1 - methylcyclohexane - 2,4 - diamine, 4,4 '- diaminodicyclohexylmethane, bis - (aminopropyl) - methylamine, N, N - bis - (aminopropyl) - piperazine, araliphalic Diamines, such as 1,5-telrahydronaphthalene, or aromatic diprimary amines, such as 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 1-methyl -2,4-diaminobenzene or araliphatic diprimary diamines, svie m-xylylenediamine, p- Xylylenediamine, a, a, a ', a' -tetramethyl-p-xylylenediamine or l, 3-bis- (/ i-aminoisopropyl) -benzene, also diamines containing sulfonic acid groups, such as 4,4'-diaminostilbene-2,2 '- disulfonic acid or 4,4 '- diaminodiphenylethane - 2,2 - disulfonic acid, hexamethylenediamine - 1,6 - N - butylsulfonic acid, 1,6-hexamethylene-3-sulfonic acid or its alkali salts. Hydrazide compounds such as carbodihydrazide, adipic acid dihydrazide, succinic acid dihydrazide. Glutaric acid dihydrazide, pimelic acid dihydrazide, hydracrylic acid dihydrazide, terephthalic acid dihydrazide. Isophthalic acid dihydrazide, β - Semicarbazidoäthancarbazinester, β - Aminoäthylsemicarbazid, β - Semicarbazidopropionsäurehydrazid, 4 - Semicarbazidobenzoesäurehydrazid or further hydrazine hydrate or N, N'-diaminopiperazine. These chain extenders can be used individually, in a mixture or together with water. Secondary diamines, preferably with a symmetrical structure, such as piperazine or 2,5-dimethylpiperazine, can also be used (but expediently less than 30 mol percent.

When using chain extension mixtures, the solubility of the polyurethane ureas usually increases, and the melting point of the polyurethanes decreases. As preferred chain extenders are ethylenediamine, m-xylylene diamine. Hydrazine, carbodihydrazide, aliphatic dicarboxylic acid hydrazides, such as glutaric acid dihydrazide. further Water used. If these chain extenders are used together with others, then theirs should be Amount be at least 50 mole percent, preferably more than 80 mole percent of the total amount.

The NCO pre-adducts are reacted with the chain extenders in highly polar, water-soluble solvents boiling above 130 ° C. Mention should be made of solvents containing amide or sulfoxide groups with the ability to enter into strong hydrogen bonds, for example dimethylformamide, N-methylpyrrolidone, diethylformamide, dimethylacetamide, formylmorpho-Hn. 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 alone cannot dissolve the polyurethane ureas, can be added to the highly polar amide solvents, e.g. B. tetrahydrofuran, dioxane, acetone or GIykolmonomethylätheracetat. The concentration of the polyurethane solutions should preferably be about 5 to 33 percent by weight, especially 15 to 27 percent by weight, the viscosities preferably being between 1 and 1000 P, especially between 5 (3 to 800 P / 25 ^° C.).

Further suitable polyurethanes are also those obtained by reacting bis-chlorocarbonic acid esters and diamines or from bis-carboxylic acid chlorides and diamines have been obtained (with preferential

wise one of the components is a higher molecular weight compound with a molecular weight of about 400 to 5000). Examples are reaction products of higher molecular weight bis-chloroformic acid esters of polyhydroxyl compounds with diamines as well as reaction products of higher molecular weight compounds with amino end groups (produced e.g. from polyhydroxyl compounds, diisocyanates and chain lengthening with noticeably excess amounts of chain end groups containing NH ₂ or bischloride chlorides) and bischloric acid chlorides. Such connections are z. See, for example, U.S. Patents 2929801, 2929 802, 2962470, 2957852. Segmented polyester or polyether methanes, as described, for example, in French patents 1,354,553 and 1,359,090 and in Belgian patent 574,385, are also suitable. Mechanical strength values or elastic properties, e.g. B. determined after cutting the foils to strips or threads. Solid foils made from polyurethanes particularly suitable for the process according to the invention have the following properties:

1. Melting point on the Kofler bench at least 180 C, preferably above 200 ° C,

2. Tear strength of at least 200 kg / cm ² , preferably 300 to 800 kg / cm ² ,

3. Elongation at break at least 200%, preferably 400 to 800%,

4. Tension forces in the first expansion to 20%: at least 5.0 kg / cm ² , preferably 10 to 30 kg / cm ² : in the expansion to 100%: at least 20 kg / cm ² , preferably 45 to 75 kg / cm ² , for 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 > _n of at least 0.6, preferably 0.90 to 1.9

In

with C = concentration in g / 100 ml, j _{/ Jt} = viscosity of a 1 percent by weight solution of the polyurethane

in phosphoric acid trisdimethylamide at 25 ⁰ 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:

where χ is 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 module in g / dtex, g is the measure of the density in g / cm ³ .

If the tensile strength or modulus values y are expressed in mg / dtex, the relationship χ = gy applies, where χ and ο have the above meaning.

Solid polyurethane films generally have the following density:

Polyester polyurethanes y = about 1.2 g / cm ^3, polyether polyurethanes η = about 1.0-1.05 g / cm ³

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 coagulable

ίο Polyurethane solution, cationic aqueous polyurethane dispersions can be added, in amounts up to 35 percent by weight (each based on solid polyurethane based). These are, in particular, polyurethanes containing quaternary ammonium groups with a

ι s certain hydrophilic character that exist in water or aqueous liquids e.g. B. water / dimethylformamide mixtures. preferably in mixed proportions 1: 1, dispersed or colloidally dissolved without the aid of emulsifiers or wetting agents.

Cationic polyurethanes suitable for this purpose are e.g. B. obtained according to the German interpretative document 1 270 276, if at least one component with one or more basic components is used in the construction of the polyurethane tertiary nitrogen atoms has also 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 the basic

jo see nitrogen atoms are located. One can also Reacting polyurethanes with reactive halogen atoms capable of quaternizing with tertiary amines. Furthermore, one can also produce polyurethanes with chain-building quaternization by one z. B. from optionally higher molecular weight diols and isocyanates with reactive halogen atoms or Diisocyanates and haloalcohols Dihalogenurethane produces and these with ditertiary amines implements. Conversely, one can choose from compounds with two isocyanate groups and tertiary amino alcohols Prepare ditertiary diaminourethanes and these with reactive dihalogen compounds implement. Of course, the cationic polyurethane composition can also consist of a cationic, salt-like one Starting component, such as a quaternized basic polyether or a quaternary Nitrogen containing isocyanate, to be produced. B. in the German see exposition 1 184946. 1 178 586, 1 179 36:

and Belgian patents 653 223, 658 026 636 799. There are also those to be set up of the salt-like polyurethanes suitable starting

materials listed.

The polyurethane mass can be next to the urethane

SS gruppen also contain urea groups.

In order to obtain a satisfactory property profile of the end product, the content of urethane and optionally urea groups are 8 to 35 percent by weight of the polyurethane composition. De Quaternary ammonium grap content should be approx

0.5 to ZO percent by weight, preferably 0.8 to 1.8 percent by weight, of the polyurethane mass is "

The aqueous dispersions or colloidal solvents

Some of these cationic polyurethanes have:

<> 5 sizes between approximately 10 and 1000 ηαμ. Si can also contain organic solvents in an amount up to about 50%, for example acetone ode Dimethylformamide. So you need that for the Hei

e ";." snit saturated water

The method _{according to the invention prefers the} p emea tion coefficient PK ^, ^ f _0n

weightSOOtoSOOO ^ olyisocyanates.einemasic Torr

"hen chain extenders, such as preferably d Ans. as well as the

In the polyurethane mass 5 to 12% NM «hyl diethaoolamine is incorporated. Up to 60% of the tertiary nitrogen built in as a result of this is made up of an alkylating agent such as dimethyl sulfate. Methylchlomelhyläther D, _a thyl _S u- «fal or bromoethanol, quatcrniert and 30 to 70 /. with you, acid, such as hydrochloric acid, lactic acid or acetic

Ur = TiA ^: _m S filming in general, the more medr, outer.

"'3 ⁰ ^ WMsrrdamprdurchtaaigkeit to» der je greater α _{her Wa5Seldam} pfd „r _C h.

PK-We ^ "j _ewe ili ₈ eu strength properties" ^sl £ ^h _e ^a S _"e idend, on the goodness un« I Gto *. "" ?? ■■ "er microporous structure. «Oak through ™» «^ ™ ^ aguUtion procedure behave.

"^ r

Manufacture of the micropor. »»

2 ™ rosen! Rachengebi.de then a networking ₄ "Ä Po.yureth.ne are then in to a

4 "» "7

appropriate values for the solid film from ά: η Pol_y-

on the microporous films, the lower the ho the water vapor permeability of the material

* kU

Determination of the water vapor permeability

at 20 ⁰ C) or according to a new method which allows much faster determinations and which uses the so-called Pe ™ «;» as a measured value. ⁰¹¹ »^^; The measurement or evaluation of the measurement results is carried out as follows:

- Layer thickness depends on the

The thickness of the microporous paints is usually the _{same as} the layer thicknesses of the polyurethane mixtures of ^ S ^ is

'S with ST polyurethane compound

i off? a:

or

_{ff e.g.} Perfluorpolyathy en, be _{bebahnen be} used when fS ^ polyurethane films are desired, the abge-P ° [° ~ _{'d uf another} example, porous substrates J ° ™ JJ _{"s, for} B are to be glued. Suitable f" ^ _az. B. Wood Split leather, cardboard, paper J _{the woven} or non-woven flat textile structure, masonry or Me * ,.

IS

A. Experiments without using a cationic polyurethane dispersion

A1) Manufacturing instructions for the

Polyurethane solutions

Polyurethane a)

6000 parts of an adipic acid mixed polyester (1,6-hexanediol and 2,2-dimethylpropanediol- _{1,3 in (0} molar ratio 65:35) with an OH number of 66.3 are mixed with 1550 parts of diphenylmethane-4,4'- diisocyanate and 1895 parts of dimethylformamide heated 170 minutes at 50 ^c C. until the NCO content of 2.35% is Voradduktlösung (equivalent to 2.93% NCO in the solids). in a 70 ° C hot solution of 190 parts of carbodihydrazide in 16,010 7525 parts of the above NCO adduct solution are allowed to flow in parts of dimethylformamide with stirring, a clear, homogeneous solution with a viscosity of 506 P being formed.

"5

Polyurethane b)

HH) O parts of an adipic acid mixed polyester (ethylene glycol / 1,4-butanediol in a molar 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 31.15 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-1,6-diisocyanate become a clear, homogeneous solution with a viscosity of 530 P. receive.

Polyurethane

1000 parts of the polyester (OH number 66.9) described in a) diphenylmethane-4,4'-diisocyanate with 50 parts of 2 ^ -Dimethylpropandiol-1,3, 373 parts and 356 parts of dimethylformamide for 50 minutes at 60 ^c C for NCO pre-adduct (2.39% NCO in the solid substance) implemented. 316 parts of the same are introduced into a solution of 6.6 parts of carbodihydrazide in 681 parts of dimethylformamide to form a homogeneous solution (600 P). /, = 1.26.

Polyurethane g)

1,000 parts of the polyester from a), 239 parts of diphenylmethane-4,4'-diisocyanate and 310 parts of dimethylformamide are reacted 57 minutes at 45 to 50 ⁰ C to the NCO preadduct and 212 parts of the same in a solution of 4.42 parts of carbodihydrazide in 452 parts of dimethylformamide entered to form a solution with a viscosity of 1010 P.

Polyurethane h)

1000 parts of an adipic acid-hexanediol-1,6 / 2,2-dimethylpropanediol-1,3-mixed polyester (Diol ratio 65:35) the OH number 65.9, with 250 parts Diphenylmethane-4,4'-diisocyanate and 313 parts of dimethylformamide heated to 45 to 50 ° C for 125 minutes until the NCO content is 2.6% (based on solids).

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, to form a homogeneous solution ' (565 P / 20 C).

Polyurethane c) polyurethane 1)

269 parts of the NCO pre-adduct solution prepared according to the previous example are in a suspension, 800 parts of an adipic acid-butanediol polyester of ₄ o are prepared by throwing in solid carbonic acid OH number 119 with 314 parts of diphenylmethane in a solution of 4.10 parts of ethylenediamine in 4,4'-diisocyanate and 280 parts of dimethylformamide '"™"

Reacted for 25 minutes at 55 ⁰ C until the NCO content was 2.93% (based on solids) is. 421 parts of this solution are stirred in with a solution of 10.82 parts of carbodihydrazide in 910 parts of dimethylformamide, 562 parts of dimethylacetamide, to form a clear, homogeneous solution of 315 P.

to a clear
mixed.

homogeneous solution (750P / 20 ^c C)

Polyurethane d)

800 parts of a butanediol / adipic acid polyester of OH number! 113 are heated with 305 parts of diphenylmethane-4,4'-diisocyanate and 277 parts of dimethylformamide at 50 ° C. for 25 minutes until the NCO content has fallen to 2.98%. 413 parts of the NCO pre-adduct are stirred into a solution of 11 parts of carbodihydrazide in 910 parts of dimethylformamide, a homogeneous solution of 650 P being obtained.

Polyurethane k)

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

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

Polyurethane 1)

245 parts of the NCO pre-adduct solution described for polyurethane k) are in a finely divided suspension

phenylmethane-4,4-diisocyanate and 253 parts of Di sion, prepared by introducing 5 parts of solid methylformamide for 25 minutes at 55 ° C to NCO-65 carbonic acid in a solution of 2.87 parts of hydrazine adduct. 413 parts of this NCO pre-adduct hydrate in 559 parts of dimethylformamide are stirred in with 11.0 parts of carbodihydrazide and 910 parts, a homogeneous solution of dimethylformamide being converted into a solution (400 P) _{with evolution of CO 2.} (290 P / 20 "C), its viscosity according to

Polyurethane e)

800 parts of a butanediol -1,4 / adipic acid polyester the OH number is 69.3 with 217 parts of diphenylmethane-4,4'-diisocyanate and 253 parts Difid 25 Mi b

Addition of 0.2 parts of hexane-1,6-diisocyanate 170 P.

Polyurethane m)

257 parts of the NCO-VOradduktlösung described for polyurethane k) are in a suspension made by adding 8 teaspoons of solid carbonic acid in a solution of 3.32 parts ethylenediamiii in SOOTeUen dimethylformamide, with the formation of a stirred in viscous solution, the viscosity of which after the addition of 0.4TeUen hexane-1,6-diisocyanate further increases to 506 P / 20 ° C.

Polyurethane n)

800 parts of an adipic acid-hexanediol-l ^ / l ^ -diis methylpropanediol-l ^ mixed polyester (diol ratio 65:35), OH number 65.9, and 98 TeUe of 2,2-dimethylpropanediol-1,3 with a solution of 451 parts of diphenylmethane-4,4'-diisocyanate and 339 parts of dimethylformamide were mixed at 50 ⁰ C, where the κ> temperature rises briefly to 88 C. 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). * 5

266 parts of the NCO pre-adduct are dissolved in a solution of 9.72 parts of 0-semicarbazidopropionic acid hydrazide in 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 / 1,4-butanediol mixed polyester (OH number 54.8) are added together with 35.2 parts of 1,4-butanediol to a solution of 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 held at this temperature for 30 minutes. The cloudy NCO pre-adduct mixture has an NCO content of 2.86% NCO (in the solid).

10.58 parts carbodihydrazide are dissolved at 60 to 70 ⁰ C in 910 parts of dimethylformamide and above with 430 parts of NCO-Voradduktlösung stirred. The homogeneous, clear solution (180 P / 20 ° C) increases after the addition of 0.5 parts of diphenylmethane ^^ '- diisocyanate to a viscosity of 630 P.

entered with stirring, a clear solution of 555 P / 20 ° C being obtained.

Polyurethane q) 14 9 parts of carbodihydrazide are in 1325 parts

Polyurethane r)

By esterifying 1752 parts of adipic acid, 762 parts of terephthalic acid bishydroxyethyl ester and AQS-TV en Äthvlenglykol, a polyester of OH öS ^ 77 9 is produced. 600,000 of the same? m 5 parts of diphenylmethane-4,4'-diisocyanate and i ί ^ dimethylformamide to the NCO pre-adduct '.. _the NCO pre-adduct solution ÄtSSung of 123 parts ^ Carbod? hydrazide reacted in 1136 parts of dimethylformamide to form a solution with a viscosity of 880 P. Polyurethane s)

By esterifying 1752 parts of adipic acid. 76 parts of bisydroxyethyl terephthalate and 1,328 parts of 1,6-hexanediol, a polyester with an OH number of 67 is produced. 600 parts of the Po yesters be -dnsocyanat with 157.5 parts of diphenylmethane-M ™ 90 parts dimethylformamide be 40 minutes converted 55 <C. 535 parts of the NCO pre-adduct formed are stirred into a solution of 1295 parts of carbodihydrazide in 42 parts of dimethylformamide sterile> a solution with a viscosity of 660 P.

Polyurethane t)

A polyester of the composition as in r) with r 47 becomes 600 parts with 128 parts

and 183 parts of

Polyurethane p)

<o

800 parts of an adipic acid-ethylene glycol 1,4-butanediol 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 mixed at 40 ° C, wherein the reaction temperature rises to 8? ° C, but is brought about by cooling rapidly to about 50 ⁰ C. 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 / I-semicarbazidopropionic acid hydrazide (NH ₂ - NH · CO NH CH ₂ · CH ₂ · CO · NH · NH ₂ ) in 20 parts of water and 490 parts of dimethylformamide

meinyiiuimaimuT- 'm ...

adduct implemented, which is 543 parts 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 acid-butanediol-l ^ polyester with a molecular weight of 1695 are heated to 5OC for 100 minutes with 155.3 parts of r) phenylmethane-4,4'-diisocyanate and 189 parts of methylformamide. I. · -Iu NCO Gehait 2.855% (based on Festsub ^ in ^Λ is 532 parts of the NCO-Voradduktlösung grazed with a solution of 13.15 parts of carbodihydrazide in 1139 parts of dimethylformamide at 65 ^C C stirred to give a homogeneous. Forms a solution with a viscosity of 700 P / 20 C.

Polyurethane v)

1100 parts of a mixed polyester of adipic acid-1,6-hexanediol and 2,2-dimethylpropanediol-1,3 in a molar ratio 65:35 (OH number 65.9) are mixed with 659 g of a solution of 331 parts of 4,4'-diphenylmethane diisocyanate , reacted for 5 hours between 50 and 6O ⁰ C in 373 parts of dimethylformamide, which had an NCO content of 6.35% after 30 minutes of standing. The NCO content of the pre-adduct is then 3.32% based on the solid substance.

162 parts of the above NCO pre-adduct will be

stirred into a solution of 362 parts of dimethylformamide and 4.6 parts of carbodihydrazide at 50 to 60 ° C The solution then has at 20 ⁰ C a viscosity of 855 P.

Polyurethane νή

160 parts of the above NC O preadduct are stirred into a solution of 340 parts of dimethylformamide and 9.55 parts Pimelinsäuredihydrazid at 60 to 80 ^c C. The solution has a viscosity ι ο of 800 P.

Polyurethane x)

150 parts of the v) instructions described in NCO preadduct be in a solution of 340 parts of dimethylformamide 10.3 parts of un Korksäuredihydrazid at 70 to 8O ⁰ C is stirred in. After cooling, the solution has a viscosity of 630 P at 2O ⁰ C.

Polyurethane y)

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

Polyurethane z)

150 parts of adipic acid / 1,4-butanediol polyester (molecular weight about 950) are combined with 133 g of a Solution of 90 parts of 4,4'-DiphenyImethandiisocyanat in 67 parts of dimethylformamide, which after 30min utigem 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-preadduct, is stirred in a solution of 425 parts of dimethylformamide and 9.75 parts of carbodihydrazide, which was dissolved hot in 19.5 parts of water at 30 to 40 ⁰ C. After the reaction, the 26% solution has a viscosity at 20 ⁰ C 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'-diphenylmethane diisocyanate in 267 parts of dimethylformamide, which after 30 minutes of standing had an NCO content of 13.55%, reacted at about 40 to 45 ° C. To 32.3 parts of 1,4-butanediol at between 40 and 45 ° C. are added dropwise over a period of 20 minutes. the After 90 minutes, the NCO content of the pre-adduct is 2.73% NCO based on the solid substance.

500 parts of the above NCO pre-adduct are in a solution of 1016 parts of dimethylformamide and 9.44 parts of carbodihydrazide in 18.9 parts of water was dissolved hot, stirred in at about 30 ° C. After the reaction has ended, the 20% solution is present 20 ° C a viscosity of 175 P.

Polyurethane bb)

1000 g of an adipic acid / ethylene glycol-butanediol mixed polyester (molar ratio of the glycols 1: 1; OH number 55.0; Acid number 0.70; Water content 0.01%) with 93.0 g of 1,4-butanediol, 14.4 g of titanium dioxide (Rutile) and mixed with 0.31 g of iron (III) acetylacetonate at 6OC and quickly with 400 g of stirring Diphenylmethane - 4,4 '- diisocyanate added. After a mixing time of about 3 minutes, the melt is in Poured flat bowls and reheated for 15 minutes in an oven heated to 110 ° C, then the already solidified polyurethane mass removed and granulated after cooling

To prepare a solution 250 g of granulated polyurethane having a "7, value of 0.90 are partly to 750 g of dimethylformamide at 50 to 6O ⁰ C is added with stirring until complete after about 8 hours solution has occurred, the viscosity of the solution is 35 P / 20 ° C.

Polyurethane cc)

200 parts of an adipic acid / 1,4-butanediol polyester (molecular weight about 950) are mixed 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, 38 parts of 1,4-butanediol are added dropwise over 25 minutes at the same reaction temperature. The solution becomes more viscous as the reaction time progresses. It is gradually diluted to 2 (*% with dimethylformamide. After 24 hours it has a viscosity of 1260 P.

Polyurethane dd)

200 parts of an adipic acid / 1,4-butanediol polyester (Molecular weight 400) are mixed 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.

485 parts of the above pre-adduct are in a solution of 781 parts of dimethylformamide and 19.75 parts of carbodihydrazide, which is dissolved in 39.5 parts of hot water, stirred in at between 30.degree. And 35.degree The approximately 26% solution has a viscosity before 54P.

Polyurethane ee)

210 parts of a 1 hour at 130 ° C / 12 Torr freed from volatile constituents polyester au: 1,6-hexanediol and f-caprolactone with the OH number 78.5 are cyanate with 50.5 parts of 1,6-hexamethylene diiso Stirring brought to an internal temperature of 75 to 78 ^° C. and held for 20 minutes. The hot pre-adduct melt (NCO content 4.62%) was cooled and diluted with 112 parts of dimethylformamide to form a solution with a solids content of 70%.

198 parts of this NCO pre-adduct solution werdei in a 50 to 55 ° C hot solution of 7.41 parts egg Carbodihydrazide, 14.82 parts of water and 368 parts of dimethylformamide are stirred in as quickly as possible, wöbe a solution of 320 P at 25 ° C is obtained. The solids content of the solution is 25%.

⁶ S polyurethane ff)

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

A number of 106 are heated to an internal temperature of 70 to 75 ° C. with 84.1 parts of 1,6-hexamethylene diisocyanate for 45 minutes. The NCO content of the melt is then 5.69%. After cooling to 40 to 45 ^° C. and adding 150 parts of dimethylformamide, an NCO content of 3.94% is obtained. The viscosity of the 70% pre-adduct solution is 12.3P / 25 ° C. 194 parts of the NCO-Voradduktlösung be a 50 to 55 ⁰ C hot solution of 9.29 parts of carbodihydrazide, stirred 13.94 parts of water and 375 parts of dimethylformamide. A solution of 162 P at 25 ° C. is obtained.

Polyurethane gg)

180 parts of a polycaprolactone ester according to Bei spiel ee) with the OH number 185 are with 88.2 parts 1,6-hexamethylene diisocyanate and 115 parts damsel thylformamide reacted for 20 minutes at 40 to 45 ° C. The NCO content of the pre-adduct is 4.90%.

199 parts of the above preadduct be converted into di (solution of 371 parts of dimethylformamide, 11.7 Divide carbodihydrazide and 23.4 parts of water at 50 ⁰ C. The resulting 25% solution possessing a viscosity of 216 P at 25 ° C.

Table 1
Properties of solid films of the polyurethanes used for microporous coagulation *)

Tear resistance Elongation at break Module 300% Module 150% Bl. Ohg. HDl **) Polyurethane (3rd return curve (g / dtex) (%) (mg / dtex) 300%) (%) I Cl 0.66 480 285 (mg / dtex) 23 170 C. 0.56 486 214 16 23 168 d 0.53 511 203 14th 28 168 e 0.67 546 165 7th 12th 163 f 0.78 628 103 18th 14th 160 G 0.50 520 108 18th 15th _ _ H 0.54 586 81 20th 29 i 0.57 536 137 16 15th k 0.48 588 105 22nd 17th __ 1 0.52 566 101 21 27 m 0.69 424 414 20th 27 178 η 0.63 653 132 20th 17th 170 O 0.64 490 250 19th 28 183 P. 0.69 529 241 17th 26th 169 q 0.72 619 170 18th 13th 164 r 0.73 603 134 20th 14th 167 S. 0.62 763 103 18th Π 163 t 0.82 681 97 14th 16 162 U 0.71 622 131 20th 18th 165 V 0.66 515 137 18th 21 165 W. 0.51 463 150 18th 22nd 140 X 0.53 474 162 17th 23 137 y 0.82 529 410 16 51 181 Z 1
The η, - value of the viscosity r _{/ (} = (rrtoiii j _n hexamethylphosphoramide 16 iegi for the above polyurethanes within the limits of 0. '

Up to 1Λ all protection 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 solid film.

··) HDT Heat Distortion temperature measurement specification. Belgian patent specification 734 189, with 1.8 mg / dtex as full load and as Aufhei? speed Zl ° / min is selected

A 2) Production of the microporous films
example 1

A 26% dimethylformamide solution of the polyurethane a) is βο with a dimethylformamide / water 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 applied evenly to glass plates with a squeegee. The foils are at 75 C and 90% relative humidity pre-gelled.

The foils are then coagulated in water at room temperature for 30 minutes and then dried by letting them lie at room temperature. If the steam gelation times are varied, foils with an extraordinary difference in microporosity, surface and appearance are obtained. Films with r, = 0 minutes are completely transparent, with i, =: 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 good grip is obtained with t = 30 minutes. While the quality of the surface decreases somewhat with increasing time i , the PK value reaches eil

/ ιγ

Maximum around \ _x = 40 minutes. The measured values are shown in Fig. 1. If the hot steam atmosphere is left to act for more than 2 hours, the films become completely transparent and impermeable to water vapor again. They then resemble foils that have been obtained by evaporating the solvent in a drying cabinet (see Fig. 1).

Increasing the steam temperature in the Vorgelierphase to 100 ⁰ C at 100% relative humidity, so the maximum of the microporosity of the films is faster (approximately 20 to 30 minutes) is reached and after only 1 hour exposure time of the vapor start the films again less vapor permeable or to become partially transparent.

It can be seen from the example that for a certain substance under the action of steam certain temperature and humidity, there is a maximum range that corresponds to the desired Microporosity provides (see Fig. 1).

Comparative experiment 1.1

Leaving the same solution as in Example 1 in the moist for a period of 1 to 120 minutes Atmosphere (approx. 22 C 60% relative humidity) to pre-gel and then proceed as given in Example 1, only transparent or predominantly transparent films are obtained with a rough surface and a strong tendency to curl.

Comparative experiment 1.2

(according to German interpretation 1 238 206.
analogous to example 1)

A 23% strength dimethylformamide solution of the polyurethane a) is evenly applied to a with a doctor blade Glass plate applied, so that a film about 1.2 mm thick is formed. One dips this slide directly 2 minutes in water at 95 ° C and then in water at around 20 ° C and air-dry at 60 ° C. After drying, it becomes a transparent, shrunk film with a high tendency to curl obtained which has no microporosity and has an extremely low coefficient of permeability (<200).

Comparative experiment 1.3
(analogous to the German interpretation document 1 i 10 607)

A dimethylformamide solution of the polyurethane a) is applied evenly to a glass plate using a doctor blade painted on 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. It creates a coarsely structured film, which is about 80% transparent and scattered, white islands of a little more microporous Has structure, is also white at the edge in a small width of about 5 mm wide. But here too has a partially coarse-pored structure. The film in this form is far insufficient for practical use Purposes of use.

Comparative experiment 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 coagulating bath with the composition 50% dimethylformamide and 50% water soaked for 20 minutes, several hours in cold water with removal of the dimethylformamide from the film is coagulated and air-dried. It becomes a transparent one Drying, non-microporous, strongly curling film received, which only has a very low level Has permeation coefficient.

Example 2

The solution of the polyurethane b) is diluted with aqueous dimethylformamide to a solids content of 23% with a water content of 1.5 percent by weight in the total solution. The solution is ^{heated to 100 °} C. for 1 hour with stirring and painted onto glass plates. These spreads are pregelatinized for 30 minutes at a steam temperature of 70 ° C. 100% relative humidity or 100 ° C./100% relative humidity, then freed from the solvent in running water for 30 minutes, immersed in methanol for 5 minutes and then dried in warm air. Films with an extremely uniform surface, a high water vapor permeability wedge and, for this permeability, high strength are obtained (see Table 2).

Comparative experiment 2.1

If the procedure is as in Example 2, but instead of steam only moist air (23 C 55% relative humidity) is used for pre-gelling, transparent, heavily shrunk elastomer films with insufficient water vapor permeability PH · 10 ⁸ <500 are obtained.

Example 3

A dimethylformamide solution of the polyurethane i) is stirred for 2 hours at 100 ° C. and then with a doctor blade evenly applied with a thickness of 1 mm on glass plates. You leave a film 30 minutes at 100 C in steam (100% relative humidity) and another film for comparison Pre-gel for 30 minutes at room temperature and 65% relative humidity and then carry out the 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 pre-gelled in steam according to the invention is considerably higher than the values of the comparative experiment (according to the German interpretation document 1 110 607). wa <

must be attributed to the more uniform structure of the first film. Accordingly, dk The surface of the first film is smooth and even while the second film has a sponge-like structure with small vesicles on the underside.

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

ration with hot steam microporous films before improved, more even structure with improve surface properties and significantly improved strengths can be achieved.

409 646,280

26th

Table 2
Manufacturing conditions and properties of microporous films

example

Polyure
than

b
b)
b)

i
i

Additions to
PU solution

1.5% H ₂ O
1.5% H ₂ O
5.0% H ₂ O

Pretreatment of the PU solution

1 h / 100 Ih. 100 2h 100

2 h / 100 "2 h. 100

Pre-gelation conditions

(min, C r. I.)

30 / 70,100% 30/100/100% 30/100/100%

100/100% 25 65%

Coagu- Tear fracture module Stay lational fcsiiii- strain 300% Dhg. had speed (25 C) Parts ⁽ ° '"L · (mg dtex) _ (%) H, O (gdtex) 514 - 18th DMI- " 0.16 445 18th 0.13 559 19th 100/0 0.13 572 75 36 100 0 0.248 497 55 28 100/0 0.120 100Ό 100 0

PK. II) "
ι · cm · Torr Water-
steam-
through-
nonchalance
mg h · cnr 250,000 21.5 260,000 22.0 320,000 22.6 2,400 1.8 2 900 1.5

Remarks

good surfaces good lightfastness

good surfaces bad surface structure

The tear strength of the film according to Graves is door

Example 2.1; 2.2; 2.3 3.8 to 3.9 - ^ -

Example 3.1; 3.2 6.5 to 7.6 ^

Table 3
Manufacturing conditions and properties of microporous films

At-
game Poly
ure Additions to Over
plot No. 4 than PU solution the PU
solution b no PAN 1 h / l 00 ° 1 h / l 00 ° b 1% PAN I h / 100 ° 1% PAN 1 h / 100 " 1% PAN without b 3% PAN 2 h / l 00 ° 3% PAN 2 h / 100 " 3% PAN without b 5% PAN without 5% PAN without b 10% PAN without 10% PAN without

Pre-gelation conditions

(min Ct. F.)

Koagu Tear lational firm bath speed (25 C) Parts (g dtex) IH, O 0.16 DMF) 0.13 100/0 0.25 Ι0Ο-Ό 0.27 100/0 0.26 100/0 0.24 100/0 0.25 100/0 0.24 100Ό 0.27 lOO'O 0.29 100Ό 0.27 lOO'O 0.23 100 0 100 0

Elongation at break

IfI ₁ ι (Ό)

module Stay 300% Dhg. (mg dlcx) (%) 18th 18th 68 13th 71 13th 72 14th 70 14th 74 14th 66 16 77 17th 75 18th 80 19th 83 19th

PK U) "
J ...
ι ■ cm Torr Water-
steam-
through-
casual-
speed
mg h ■ cm ² 260,000 21.5 17000 8.5 21000 9.5 5,600 4.5 15000 7.5 6,800 5.0 6900 5.0 7100 4.0 4,400 3.5 4,200 3.5 2,200 1.5

Remarks

70 ", 90% 100" / 100%

787 100%

1007 100%

75 '/ 100%

777 95%

1007 100%

757 100%

78/100%

100/100%

76/100% 100, 100%

Example 4

Dissolve in the polyurethane solution b) an additional 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 performs the pre-gelation or coagulation while varying the test conditions (see Table 3), then with increasing amounts of polyacrylonitrile copolymer (PAN) a reduction in water vapor permeability and an improvement in the surface and the handle the microporous layer. In this way, a polyurethane can be optimized with regard to water Achieve vapor permeability, strength and surface properties. Neither is it too high. The grip of the film improves (becomes "drier")

515 495

590 605

585

588 590 620

605 630

635

565

a too low water vapor permeability ^{1 is still} desirable. Under the steam pre-gelation conditions, the polymer additives bring about a comparison of the microporous structure while improving the strength values of the films (result, see Table 3).

Example 5

In the following, for a large number of different polyurethane solutions in compliance with fol Under the "standard conditions", the formation of micro-porous films was carried out. The main own Shafts of the microporous films are communicated (see Table 4).

025

Standard condition for the trial seric

The solution in dimethylformamide (about 23%) with additions of 0 to 5 percent by weight of water (based on the solution), if necessary, by stirring the solution for up to two hours at 50 to 100.degree "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. The "pre-gelation" takes about 30 minutes, essentially with ι ο Steam saturated air at 75 to 100 C made. The "coagulation" of the film becomes carried out in water at room temperature with dimethylformamide contents of 0 to 20% (duration about 30 minutes). A post-treatment of the white, microporous film is carried out by a subsequent treatment Bathing the foil in methanol (up to 30 minutes residence time). The foils are dried through Lay the foils at room temperature for 2 to 15 hours, followed by drying for 5 hours at 110 C

Of all polyurethane solutions were under the Slandard conditions, but with pre-gelation in Air at room temperature and a relative humidity of 50 to 65% (exposure time 15 to 30 minutes) - Instead of the pregelatinization conditions according to the invention - films are coagulated. All these Films (except for polyurethane i and z) were completely or partially transparent, severely shrunk, from poor surface and not microporous.

Examples ^

The solution of the polyurethane z) wrqd with aqueous dimethylformamide to a solution containing 23 weight percent solids and 3 weight percent water, stirred at 50 "C for 2 hours and left to stand for 48 hours. The solution is ^{warmed to 90 0} C before pouring and immediately to a hot glass plate (approximately 90 ° C) painted. After Vorgeherung in steam atmosphere of 78 C and 95% relative humidity during a just short period of time of 1 minute, the film is coagulated followed by 30 minutes in water at 6O ⁰ C, then treated in methanol 10 minutes and then dried, giving a microporous film with smooth, homogeneous surfaces and good tear strength (0.245 mg / dtex).

If one proceeds as above, however, the pre-gelation takes place in air at 25 ° C / 50% relative humidity, a microporous film is obtained, but it is has a rough surface and only reduced strength (0.195 mg / dtex).

Example 7

A water-containing solution prepared as in Example 6, the polyurethane z) is heated to 8O ⁰ 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 and about 90 to 95% relative humidity introduced. After a running time of 5 minutes, the film is run into a coagulation bath at 70C. The foil is then placed in a second, unheated water bath, where the remaining solvent is extracted. The total residence time in the coagulation baths is about 20 to 25 minutes. The dimethylformamide concentration in baths is kept below 5% by constant renewal of the water. The cover of the hot pre-gelling bath over the polyurethane film is kept at 90 to 100 ° C. in order to avoid the formation of drops on the ceiling. After being squeezed off, the film web passes through a methanol bath at room temperature for 10 minutes, is then squeezed off again and is then 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

example
No.

5.01
5.0:
5.03 5.04 5.05 5.06 5.07

5.08 5.09
5.10
5.11 5.12 5.13 5.14

Polyure
than

b
c
defg

H k 1

nt η
ο
P.

Additions to
PU solution

5% HjO 5% HjO

5% H ₂ O
5% H ₂ O

Pretreatment the PU solution

2h / 100 2h / 100 ' 2h / 10O 2h / 1 (w 2h / lC0 2h / TO 3h / 70-2h / 100 ' 2h / 100 ° 2h / 100 '

2h / irxr

2h / 100 ^r 2h / HXr

Koagu
lation bath
Parts Tear
firm
speed fracture
strain module
300% Stay
Dhg. PK 10 "
B.
h cm ■ Torr Water- Nforgelier
Sedation (HjO steam-
through-
casual wedge
mg (C. DMF) (gdtexl <% l (mg / dtex) <%) h cm ² rel. Humidity) 100 0 0.198 487 85 21 17000 100/100% 100 0 0.178 560 62 19th 130000 8.7 100.100% 100 0 0025 366 166 26th 62000 18.6 100.100% 100 0 0.132 298 _ 27 180000 13.8 100.100% 100 0 0.164 414 115 70 310000 19.0 100,100% 90 10 0.270 453 UO 20th 12000 22.6 100,100% 90 10 0020 526 70 17th 35000 7.0 100 100% 100 0 0.166 464 81 21 66000 UO 100/100% 95 5 0.244 504 95 25th 18000 14.6 100 100% 80 20 0009 511 89 22nd 89000 8.4 100 100% 100 0 0087 580 86 31 3400 170 100 100% 90 10 0J30 359 204 41 2500 2.7 90/100% 9010 0.180 478 SI 21 110000 U 100/100% 100 0 0.400 509 153 38 3900 16.6 100.100% 2.5

Tear-resistant wide (nacl Graves

flcg / cm ^

2.3 3.1 3.1 5.1

2.42.7

30 3.4 20 2.6

2 025 / IV

30th

Poly
ure Additions to. * Over
plot Cringing continuation Tear
firm I.
Bruc at
spat] than PU solution the PU
solution conditions Coagu-
lalionsb? x speed stretch No. ( ⁰ C / Parts rel. Humidity) (H ₂ O (g / dtex) (%) q 2h / 100 ° 100/100% DMF) 0.300 443 5.15 q - - 100/100% 100 0 0.290 475 5.16 r 5% HjO - 75/95% 100 0 0.270 525 5.17 r 5% H ₂ O 1 h / l 00- 78/95% 90 10 0.220 473 5.18 r - - 78 95% 90 IO 0.300 531 5.19 S. - - 78/95% 90 IO 0.300 493 5.20 S. - 2h /! 00 ° 78/95% 90 IO 0.210 473 5.21 S. 5% HjO I h / 100 " 7S <95% 90 IO 0.170 452 5.22 t - 2h / IO0 ' 75/90% 90 10 0.190 575 5.23 t 5% H ₂ O - 75/90% 90.10 0.220 515 5.24 U - - 78/95% 90 10 0.250 517 5.25 U 2h, 100 75.95% 100 0 0.250 j 529 5.26 U 5% HjO - 78.95% 100 0 0.290 j 539 5.27 U 5% HjO lh, 100 75 95% KX) 0 0.180! 501 5.28 V 5% HjO 1 h / 100 78 95% 100 0 0.230 j 489 5.29 W. 5% HjO IhJOO 78.95% 90 10 0.180 472 5.30 X 5% HjO lh, 100 78 95% 90 H) 0.190 481 5.31 i 5% HjO lh 100 78 95% 90.10 0.220 466 5.32 Z 2.9% H ₂ O - 75 90% 90 10 0.190 311 5.33 cc 3% HjO 2 h / l 00 78 90% 100 0 0.340 361 5.34 100 0

module 300%

(mg / dtex)

143

137

96

97

110

107

96

87

76

87

79

83

68

75

95

85

89

102

194

275

Stay
Dhg.

31

32
10
13th
8th
14th
14th
13th
14th
14th
15th
17th
17th
19th

22nd

25th

28

27

25th

87

PK 10 ⁸

h · cm ■ Torr

140000
000
17000

100,000
00
7700
000
72000
000

000
5400
15000

00
20000
50000
000
15000
000
000
120 «)

Water-

steam-

through-

casualness

mg

h ■ cm ²

19.5

11.5
6.5

16.0
3.6
4.5

16.5

15.0

11.9

14.7

4.4

7.4

4.2

8.5
12.0
11, "

6.5
11.0
14.7

7.5

Resistant to tearing. ability (after Graves)

5.1 7.5

2.1 2.8

I.S2.I

All the films listed in the table were white as a result of the “microporosity” of the film and showed good, smooth surfaces. The microporous films showed no damage after 200,000 kinks or deterioration of the surface.

If the methanol bath aftertreatment is dispensed with, some of the previous treatments will be applied during drying microporous films at least partially transparent (cf. 5.01, 5.06, 5.11). It also improves the Methanol aftertreatment removes the raw clay of the foils and facilitates the drying of the microporous ones Slides extraordinary.

nol bathed and then dried at 110 C to / u for 5 hours.

Uniformly microporous films with smooth surfaces are obtained. The measured values (Table 5) show that the water vapor permeability of the films is controlled by the gelation times in hot steam can be, which can be achieved with hot steam treatment of 1 to 4 minutes an essential Can improve the properties against gelation in humid air at room temperature.

Example 9 Example 8

A solution of the polyurethane aa), bb) or dd) is diluted in aqueous dimethylformamide optionally in a 23 weight percent solution containing, for 1 hour at looc and then coated with 8O ⁰ C on preheated glass plates. After different gel times (see Table 5) in hot steam or in moist air at room temperature, the films are coagulated for 30 minutes in water at 25 ° C., for 20 minutes in metha-A 22% dimethylformamide solution of the polyurethane ee), ff) or gg), which still contains about 3% water, is evenly applied to a glass plate 1.35 mm thick with a squeegee. The film is allowed to gel for a few minutes at 75 ° C. in saturated steam and then coagulation is carried out in water (15 minutes on the plate, 30 minutes without the plate) at room temperature. After drying for one hour at 70 to 80 ° C., the films show a uniformly microporous structure (measured values in Table 6).

table

Polyurethane

aa
aa
aa
aa

Gelling conditions

(min / Cr. F.)

30/78/95%
2/77/95%
1/76/95%

10/25/65%

Tear resistance
(g / dlex)

0.27
0.14
0.14
0.11

Elongation at break

246 178 172 137

Module 100 ". dlcx) (ΠΙ}. 31 1 10 1 10 1 10 1

PK 10 "

JL

h cm torr

160 (X) O

000

40000

800

Wiisscrdanipfdurchlüssigkcii

ηιμ
h ■ cnr

18.4

10.5

9.5

easy-

it
ι.
η -t

continuation

Polyi'reihan

bb
bb
bb

dd
dd
dd

Gelling conditions

(min, Cr F.)

30/78/95%

4/90/95%

10/25/65%

30/78/95%

4/90/95%

10/25/65%

Tear resistance
(g / dtex)

0.13
0.11
0.05

0.18
0.22
0.17

Elongation at break

example

No

7.2

7.3

Pol \ urethane

ee

ff
gg

/ usä; / e 7ur

Pohurelhun-

I osnnj!

3.3% H ₂ O
2.8% H ₂ O
3.9% H, O

¹ (lelier-
! conditions!

j (now I ι

I 3.575 j
I 1.5 75,

'· 1.3 75 i

604 528

427

148 155 119

table

parts H, O DMl-

100 100 100 module 100%

(mgdtex)

23
21
17th

145
160
160

PK 10 "
ε

h · cm · Torr

380,000
28,000
17000

84000

11000

1600

Water vapor permeable wedge
mg

Tear resistance.

Kp cm '.
Uinu ·. across * I

91.6 51.4
102 85
78.9 54.9

Elongation at break

495
625
485

White tear resistance.

(Kp cm.

lengthways across * \

7.8 5.0

10.8 7.S

2.0 1.8

25th
9.8
6.4

11.4
6.0
0.5

Wasscrdampfdurchiki

mg
h cm ²

4.9
5.3
6.9

♦) / "ur direction of winding up the high

B. Experiments using a cationic
Polyurethane dispersion

B1) Manufacturing instructions for the
Polyurethane ureas a)

Polyurethane urea a, I

4470 parts (parts by weight are always given) of a 1 hour at 130 C 12 Torr dehydrated Polyester made from adipic acid and 1,4-butanediol with the The OH number is 50.2 with 674 parts of hexamethylene-1,6-diisocyanal (Molar ratio of polyester to diisocyanate == 1: 2) with stirring to an internal temperature brought from 89 to 91 C and held for 25 minutes. The hot NCO pre-adduct melt (NCO content 3.82%), after cooling to 55 ° C., 2206 parts of dimethylformamide are added. The NCO content of the Pre-adduct solution is 2.55%.

5980 parts of the above pre-adduct solution are in a 50 to 55 C hot solution of 173 parts of carbodihydrazide, 346 parts of water and 11 040 parts of dimethylformamide entered, a homogeneous solution with a viscosity of 196 P / 25 C at 24.9% solids concentration results. The properties of the elastomer substance (measured at approx 0.2 mm thick foils, which are produced by knife-coating the solution onto glass plates and evaporating the solvent at 100 C) are listed in Table 1. The films show excellent durability against yellowing and mechanical degradation.

Polyurethane urea a / 2

3440 Parts of one described in regulation a / l Polyester with an OH number of 52.2 and 47.6 parts of N-methyldiethanolamine (molar ratio of polyester to Aminol = 0.8: 0.2) are mixed with 952 parts of diphenylmethane-4,4'-diisocyanate and 2550 parts of dimethylformamide at 30 "C for 15 minutes.

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

Polyurethane urea a 3

3930 parts of a polyester made from adipic acid and diethylene glycol with an OH number of 42.9 are _{stirred at 60 ° C. with 7 parts of a 35% strength solution of SO 2} in dioxane for 15 minutes and then freed from volatile Besland parts at 12 torr 120 ° C. for 30 minutes . The polyester pretreated in this way is heated to 35 to 40 ° C. for 15 minutes with 750 parts of diphenylmethane-4,4'-diisocyanate and 2010 parts of dimethylformamide. 4050 parts of the NCO pre-adduct solution (NCO content 1.70% are reacted with 76 parts of carbodihydrazide dissolved in 152 parts of water and 7272 parts of dimethylformamide to give a clear solution with a viscosity of 162 P / 25 ° C. Solids 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 1,4-Butanediol (molar ratio!: 1) with an OH number of 57 are mixed with 640 parts of hexamethylene-l.o-diisocyanate Reacted for 30 minutes at 92 ° C., cooled and mixed with 1960 parts of dimethylformamide to form the NCO pre-adduct solution (2.1% NCO) diluted.

1990 parts of this solution are added to the mixture

f> 5 from 44.7 parts of carbidohydrazide, 67.1 parts of water

and stirred in 3678 parts of dimethylformamide. the

25.1% solution has a viscosity of 276 P 25 C.

409 646/280

/ 1 * 1

Polyurethane urea a 5

7200 parts of a polyester made from adipic acid and 1,4-butanediol (OH number 62.4) are reacted at S5 C for 40 minutes with 1280 parts of hexamethylene-1,6-diisocyanate. The melt, cooled to 60 ^° C., is stirred with 3568 parts of dimethylformamide.

3950 parts of the NCO pre-adduct solution (2.29% NCO) result with 105.4 parts of carbodihydrazide dissolved in 210 parts of water and 7304 parts of dimethylformamide, 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 Procedure a / 5 are heated with 1253 parts of diphenylmethane diisocyanate and 2477 parts of dimethylformamide, 10 minutes 40 C ^c.

6250 parts of the NCO pre-adduct solution (NCO content 2.28%) are added to the solution of 161.3 parts Carbodihydrazide, 322.6 parts of water and 10966 parts of dimethylformamide entered with formation a solution of 225 P (25.4% solids).

Polyurethane urea a ¹ I

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 529 parts of diphenylmethane diisocyanate reacted in 2280 parts of dimethylformamide at 25 C. After 10 minutes the NCO content is 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 3998 parts of the above NCO pre-adduct solution are stirred in, a solution (25%) with a A viscosity of 143 P / 25 C arises.

Polyurethane urea a / 8

4160 parts of a polyester made from adipic acid and diethylene glycol with an OH number of 54.0 are used 673 parts of hexamethylene 1,6-diisocyanate were reacted at 92 ° C. for 25 minutes. After cooling down 2075 parts of dimethylformamide are added to the melt at 60.degree.

3980 parts of this NCO pre-adduct (2.24% NCO) are mixed 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 249%

Polyurethane urea a / 9

5000 parts of an adipic acid, ethylene glycol-butanediol-1,4 mixed polyester (Molar ratio of glycols 1: 1) with an OH number of 57.2 are 1205 parts Diphenylmethane-4,4'-diisocyanate and 2,650 parts of dimethylformamide were added. The temperature during stirring for 55 minutes is kept at 40.degree. 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 330P / 25 ° C and a solids content of 25.1%.

Polyurethane urea a / 10

3400 parts of a mixed polyester of adipic acid and 1,6-hexanediol treated according to regulation a / l

2,2-Dimethylpropanediol-1,3 (molar ratio of Glj-j kol mixture 65:35) with the OH number 66 are mixed with 1001 parts of diphenylmethane diisocyanate in 1884 parts len dimethylformamide for 40 minutes at 35 C to an NCO content of 2.38%.

4030 parts of NCO pre-adduct react with 109.6 parts | len carbodihydrazide, 219.2 parts of water and | 7312 parts of dimethylformamide to a clear solution I. of 272 P 25'C with 25.2% solids content. I.

Polyurethane urea all f

2100 parts of a polyester of caprolactone and \ 1,6-hexanediol having a molecular weight of 1410 I will be at 74 to 76 C with 505 parts of hexamethylene |

diisocyanate reacted for 35 minutes. After cooling and adding 1120 parts of dimethylformamide one an NCO pre-adduct solution with 3.1% NCO.

1980 parts of this NCO pre-adduct are added to the solution of 71.5 parts of carbodihydrazide and 107.3 parts Stir in water and 3721 parts of dimethylformamide. The viscosity of the resulting homogeneous Solution is 183 P 25 C (24.9% solids).

Polyurethane urea a 12

2640 parts of a as described in regulation a, 11 Polycaprolactone esters with an OH number of 107.5 are mixed with 1252 parts of diphenylmethane diisocyanate reacted in 1680 parts of dimethylformamide for 10 minutes at 35 to 40 C.

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 ° C. (24.7% solids).

Polyurethane urea a / 13

4120 parts of an adipic acid-hexanediol polyester with the OH number 136 are at 30 to 35 C. 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%.

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

Polyurethane urea a / 14

4120 parts of this polyester from regulation a 13 are advanced in 202.5 parts of dimethylformamide with 625 parts of dipheny-phantic isocyanate. After stirring for 10 minutes at 30 to. At 40 ° C., the NCO content approaches 0. 74.5 parts of N-methyldiethanolamine, 1495 parts of diphenylmethane diisocyanate and 4110 parts of dimethylformamide are stirred into this solution. After 12 minutes the NCO content is 1.75%.
6030 parts of this NCO-Voradduktlösung are stirred into the heated to 55 ^J C solution of 124 parts of carbodihydrazide, 248 parts of water and 6228 parts of dimethylformamide to obtain a solution having a viscosity of 186 P / 25 ° C is produced (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 with 960 parts of 1,6-hexamethylene diisocyanate at 05 ° C. for 8 minutes. the 1180 parts of dimethylformamide are added to the melt. The NCO content of the pre-adduct is 4.93%.

1998 parts of this pre-adduct solution are stirred into 117 parts of carbodihydrazide dissolved in 234 parts of water and 3710 parts of dimethylformamide. The solution viscosity is 216 P / 25 ^D C, the solids content 25%.

Table 7
Properties of polyurethane urea solutions and foils

% NCO in Viscosity of the Solids content Testing of elastomer foils tensile strenght Elongation at break to staff Tear on Pokurethane NCO pre-adduct Solution in P 25 C samples according to DIN 53: in kg / cm ² in % 504 strength in kg cm ureas a 24.9 540 965 58.0 2.55 196 24.6 565 905 69.0 a / l 1.49 190 25.2 570 890 62.0 a / 2 1.70 162 25.1 545 920 56.0 a / 3 2.10 276 24.3 515 920 74.4 a / 4 2.29 157 25.4 575 890 81.7 a / 5 2.28 225 25.0 520 860 68.5 a / 6 1.23 143 24.9 460 875 54.2 a7 2.24 133 25.1 550 1085 47.2 a 8 2.06 330 25.2 545 855 42.6 a9 2.38 272 24.9 598 795 64.0 a / 10 3.1 183 24.7 570 620 52.1 a / 11 3.41 160 24.8 558 582 41.1 a / 12 2.15 232 25.1 755 555 36.7 a 13 1.75 186 25.0 610 560 39.4 a / 14 4.93 216 a / 15

Manufacturing instructions for the
cationic polyurethanes b

Cationic polyurethane b / 1

1000 parts of a polyester with an OH number of 62 and a water content of less than 0.1% made from phthalic acid, adipic acid and ethylene glycol (molar ratio 1: 1: 2.2) is mixed with 257 parts of toluene diisocyanate (mixture of isomers 65:35) for 120 minutes 7O ⁰ C implemented. To the resulting viscous pre-adduct are added successively 840 parts of dimethylformamide and 107 parts of N-methyldiethanolamine and the mixture is stirred at 50 ⁰ C until the viscosity of 60 P at IGT. A solution of 6.5 parts of dibutylamine in 60 parts of dimethylformamide and a solution of 50 parts of 1, S-dimethyl-o-bis-chloromethylbenzene in 193 parts of dimethylformamide are then added in succession. The mixture is stirred at 50 ⁰ C until a viscosity of 45 P is reached. A solution of 29 parts of phosphoric acid in 120 parts of water, 1065 parts of dimethylformamide and 1300 parts of water at 50 ^° C. is then added one after the other. After cooling, a 28.5% white dispersion is obtained.

Cationic polyurethane b / 4

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

Cationic polyurethane b / 5

The procedure is as in regulation b / 1, but using 30 parts of benzyl chloride instead des 1,3-dimethyl-4,6-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 _{The procedure is wk jn} regulation b / 1, but below

The procedure is as in regulation 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!, S-dimethyl ^ o-bis-chloromethylbenzene

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

is coarser. of polyurethane.

Cationic polyurethane b / 3

Proceed as in regulation b / 1, but under

Use of 87 parts conc. Hydrochloric acid. Man /

receives a 28.5% opaque, viscous polyurethane-phthalic acid dichloride in place of the 1,3-dimet
solution. 4,6-bis-chloromethylbenzene is used. It results

Cationic polyurethane b / 8

Proceed as in regulation b / 1, but with

imetHyl-

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

Cationic polyurethane b / 9

Proceed as in regulation b / 1. however under Use of 30 parts of 1,4-dichloromethylbenzene instead of the l ^ -dimethyl ^ o-bis-chloromethylbenzene. A thin, 28.5% strength dispersion is obtained.

B 2) Manufacture of microporous films

Example 10

400 parts by weight of the solution of polyurethane urea according to regulation a / 2 in dimethylformamide, which is 24.6%, are mixed with a solution of 38.4 parts of the cationic polyurethane solution according to regulation b / 1, to which a further 7.6 parts of dimethylformamide are added are stirred intensively at room temperature. The mixture is 22% and has a viscosity of 116P / 25 ^C 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 warm box, which is filled with relaxed steam! is. and left in the steam atmosphere for 5 minutes, after which the solution gelled. The plate is then placed in a water bath where the dimethylformamide is washed out. The resulting porous film is peeled off the base after 15 minutes, left in the water bath for a further 30 minutes and then squeezed off five times and soaked again with water in between. After the fifth squeezing, the white, 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 88) of 16.1 mg / cm ² .

Example 11

300 parts of a 25.1% solution of the Pohurethanliarnstoffs a / 9 in dimethylformamide are intensively mixed with 46.6 parts of a cationic polyurethane solution in dimethylformamide (28.5% according to regulation b 1 with 56 parts of dimethylformamide. The solution is 22% solids and 4.5 The viscosity is 214 P / 25 ^° C. The solution is slowly stirred for 1 hour at 70 ° C., degassed in vacuo and, as in Example 10. The solution is applied with a knife for 2 ¹ minutes left in the steam atmosphere and then treated further in a water bath as in Example 1. The film produced in this way has a water vapor permeability of 18.9 mg / cm ² h.

Example 12

300 parts of the polyurethane urea solution a / 12 (in dimethylformamide. 24.7% igl with the quantities of polyurethane urea b / 1 given in Table 8 and the necessary parts of dimethylformamide, to obtain 22% solution, mixed intensively at room temperature. The samples, as in the Example 10 described, applied to a glass plate in an even layer, in a steam box (90 C, 100% rel. Humidity) for the time indicated in the table and then in a water bath End treats. After drying, the porous films have the properties listed.

Table (example 12)

Weight reduction viscosity Conc water ratios of in P / 25 tration of salary
l "nl PU after
font a 12 b 1 185 solution 6.7 80:20 172 22nd 6.1 85:15 158 22nd 5.0 90:10 139 22nd 3.97 I. 95: 5 128 22nd 3.2 98: 2 22nd

Water vapor permeability

Img cnr'h)

23.3 19.1 y 16.4 i IZl 9.8 Gclicr7cit

(Min)

0.5 0.7

0.8
1.3
ZO

test

Tearing

kcit
(kp cnvl

51 59 66 82 94

of microporous films Tear fracture strength strain Ikp cm I <%> 5.0 ' 395 6.1 410 6.7 442 8.0 430 9.4 580

Example 13

60

400 parts of a 243% solution of the polyurethane urea a.5 in dimethylformamide are mixed 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 st iron ends Amounts (0.5 to 5%, based on the solids: Table 9) polyacrylonitrile added. The approximately 22% solutions are degassed and knife-coated according to the method given in Example 1. 5 minutes treated in a steam atmosphere (90 C; 100% relative humidity) and then in water. The microporous Films show a decrease in water vapor permeability with increasing amounts of polyacrylonitrile, but an improvement in the handle and the surface as well as an increase in the strength values. The polymer additives thus enable optimization with regard to water vapor permeability. Strength and surface

616

40

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

Polyurethane

a / 5
a / 5
a / 5
a / 5
a / 5
a / 5
a / 5
a / 5

b / l
b / l
b / l
b / l
b / l
b / l
b / l
b / l

/ usät / c / ui '
IH! Solution

no PAN
0.5% PAN
1.0% PAN
1.5% PAN
2.0% PAN
3 0% PAN
4.0% PAN
5.0% PAN

Preprocessing

conditions

(C r.] ■ ".)

90.100%
90ΊΟ0 "/ ,,
90/100%
90/100%
90 100%
90/100%
90/100%
90/100% reverse wedge
Ikp cnrl

53

66

Example 14

Elongation at break

I "ο I

500 530

455 480 525 380

545 575

Wide open Steam- strength permeability Ikp cmI ι mg cnr'hl 10.5 19.8 14.7 15.2 10.7 9.7 14.1 6.4 10.2 5.8 16.5 2.9 13.9 4.2 9.4 3.8

The solution of the polyurethane urea a / 10 is mixed with the cationic polyurethane solution Kl (a: b = 9: 1) and further dimethylformamide to a solution with a solids content of 22% and a water content of 5.2%. The solution is degassed and painted on 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

According to Example 10, those in the following Table 10 indicated polyurethane urea solutions with the indicated cationic polyurethane dispersions mixed and diluted with dimethylformamide 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 Further treated water. After drying, the water vapor permeabilities listed in Table 10 are obtained of the slides.

table

Polyurelhan urine fluids and regulations

al a.3 a 4 a 6 a / 7 a, 7 a, 7 all a, 13 a 14 al 5 a 15

Cation. ratio water Gelling Water- Poly
urethane PU a: b salary / eit steam
through In front casual font b ("ot (Min.) of the slides 90:10 4.0 10 I mg hem ² Kl 90:10 3.3 15th 14.8 b / l 90:10 3.2 5 16.1 Kl 90:10 3.8 4th 18.3 b / l 90:10 4.0 3 12.6 b2 90:10 4.0 3 13.5 K9 90:10 4.0 5 11.9 K 7 90:10 3.8 3 0.1 b'2 90:10 4.4 10 7.8 K6 90:10 4.0 8th 4.3 b9 90:10 5.6 ι 9.6 b'4 90:10 5.6 2.5 5.8 b 5 4.7

1 sheet of drawings

Claims (4)

Patent claims: ι. Process for the production of microporous fabrics from polyurethanes by pretreating thin layers of polyurethane solutions, which are optionally mixed with an aqueous cationic polyurethane dispersion, in a moist Atmosphere at elevated temperature, coagulation of the layers in water or aqueous precipitation baths with removal of the majority of the polyurethane solvent and subsequent drying, characterized in that the thin layer of the polyurethane solution is a water vapor atmosphere with a relative humidity of at least 50% at temperatures of at least 65 ° C for 0.1 to 60 minutes, after which Coagulation of the microporous polyurethane, optionally with an aliphatic alcohol, 0.2 to Treated for 30 minutes and then dried. 2. The method according to claim 1, characterized in that there is a steam atmosphere with a relative humidity of 80 to 100% and a temperature of 75 to 100 ° C 0.1 to Leave on for 30 minutes. 3. The method according to claim 1, characterized in that saturated water vapor is used the boiling temperature of the water. 4. The method according to claim 1 to 3, characterized in that the solvent-containing Polyurethanes or polyurethane mixtures in a continuous process on a production scale applies to a base, through a treatment room with a humidity of at least 50% at a temperature above 65 ° C with a retention time of 0.1 to 30 minutes leads, then removed most of the solvent in aqueous 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.