CONTACT ADHESIVE PRODUCT BASED ON POLYURETHANE UREA, ITS MANUFACTURE AND THE CORRESPONDING CONTACT ADHESIVE

Description

[0001] The present invention relates to a contact-adhesive product comprising a substrate and a specific polyurethaneurea, as well as a process for producing the contact-adhesive product. The invention also relates to a specific polyurethaneurea and a contact adhesive comprising this polyurethaneurea.

[0002] Contact adhesives are used in many applications, particularly medical ones, such as bandages for compression therapy. It is important that adhesives are used that allow the products to be stored on rolls, for example, without the individual layers sticking together so tightly that they can no longer be unwound from the roll or can only be unwound with considerable force. At the same time, however, when applied to the human body, the layers should adhere well to one another only through slight pressure or tension, but without the influence of heat, radiation or similar external effects, and reliably close the bandage. However, they should not stick to skin, hair or clothing and should also be reversibly removable and, ideally, even reusable multiple times while retaining the same adhesive properties.

[0003] Such products often use latex formulations based on natural rubber as adhesive components. However, this brings with it disadvantages such as discoloration with age, often an unpleasant odor, and not infrequently allergic skin reactions.

[0004] For example, US Pat. No. 6,156,424 describes contact-adhesive products for use in bandages or dressings based on substrates impregnated with water-based polymers. The polymers used are inherently crystalline elastomeric polymers such as polychloroprene, but also polyester polyurethanes or polycaprolactone urethanes. A disadvantage is that these can only be used in combination with certain tackifiers. Complete crystallization of the products must always be avoided, as otherwise they lose their adhesive strength. This is particularly difficult to ensure during long storage periods.

[0005] US Pat. No. 5,692,937 describes contact adhesives based on aqueous dispersions of polyester polyurethanes that are suitable for stretchable products such as bandages. However, the products described therein exhibit low contact tack, which is insufficient for many applications on their own and is therefore preferably used in combination with other adhesive dispersions based on rather undesirable polyacrylates. Furthermore, the dispersions and the adhesive films formed from them have a yellowish-brown color, which is rather unsuitable as a contact adhesive for medical products, as they give the product an unhygienic and dirty appearance.

[0006] CN104725589 A also describes the use of aqueous polyurethane dispersions for self-adhesive, elastic bandages. However, the bandages described there also lack sufficient contact adhesion.

[0007] An object of the present invention was to at least partially overcome at least one disadvantage of the prior art.

[0008] WO 2010 / 142393 A1 discloses aqueous polyurethane dispersions which are prepared by reacting at least two poly(tetramethylene glycol) polyether polyols with different average molecular weights and at least two different polyisocyanate components.

[0009] EP 2 332 998 A1 describes solvent-free, aqueous polyurethane dispersions and processes for their preparation and use.

[0010] WO 01 / 62818 A1 discloses polyurethane-based adhesives, wherein these polyurethanes are the reaction product of an isocyanate-reactive component containing at least two isocyanate-reactive materials and an isocyanate-functional component. The first isocyanate-reactive material has an average molecular weight of less than 2000 g / mol and the second of at least 2000 g / mol.

[0011] WO 2013 / 136108 relates to the use of an adhesive composition comprising at least one silyl-containing polymer, at least one compatible tackifier resin, and at least one catalyst to produce a breathable self-adhesive article. This prior art document also relates to a pressure-sensitive adhesive composition and a breathable self-adhesive article comprising at least one breathable substrate coated with a breathable adhesive layer. A further object of the present invention was to provide a contact-adhesive product that, on the one hand, can be stored on rolls without the individual layers becoming strongly adhered, but, on the other hand, the layers exhibit good adhesion to one another when applied to the human body without the influence of heat or the like.

[0012] Furthermore, it was an object of the present invention to provide a contact adhesive product which has a high color fastness, in particular a high light stability.

[0013] At least one of these objects could surprisingly be achieved by providing a contact adhesive product comprising a substrate and a polyurethaneurea, which is obtainable by reacting at least A) an aliphatic polyisocyanate component with an average isocyanate functionality of ≥ 1.8 and ≤ 2.6, B) a polymeric polyether-polyol component which contains or consists of a mixture of poly(tetramethylene glycol)polyether polyols, wherein the poly(tetramethylene glycol)polyether polyols differ in their number-average molecular weights, C) an amino-functional chain extender component with at least 2 isocyanate-reactive amino groups, containing at least one amino-functional compound C1) which has no ionic or ionogenic groups and one amino-functional compound C2) which has ionic or ionogenic groups, D) optionally further hydrophilizing components which are different from C2), E) optionally hydroxy-functional compounds with a molecular weight of 62 to 399 mol / g, F) ​​optionally further polymeric polyols which are different from B), G) a compound,which has exactly one isocyanate-reactive group, or a compound which has more than one isocyanate-reactive group, where only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the chosen reaction conditions and H) an aliphatic polyisocyanate component with an average isocyanate functionality of > 2.6 and ≤ 4, , wherein the molar ratio of component G) to component H) is 5:1 to 1:5 and wherein components B) and F) together contain ≤ 30 wt.% of component F), based on the total mass of components B) and F).

[0014] It was surprisingly shown that contact adhesive products could be obtained based on the special polyurethane ureas mentioned, which on the one hand can be stored on rolls without the individual layers sticking together strongly and on the other hand the layers show good adhesion to one another when applied to the human body without the influence of heat or similar.

[0015] Contact adhesive, as used herein, means that a single layer of the material in question (contact adhesive), or the product itself, exhibits no or only very low tackiness. Only upon contact and preferably pressing with a second layer of the same material or product does a bond between the two material layers form with a strong adhesive strength. The contact adhesive must therefore be applied to both parts or layers to be joined and is then preferably dried until no noticeable tackiness is present.

[0016] Polyurethane ureas in the sense of the invention are polymeric compounds which have at least two, preferably at least three, repeating units containing urethane groups:

[0017] According to the invention, the polyurethaneureas also have urea group-containing repeating units due to their production, as they are formed in particular in the reaction of isocyanate-terminated prepolymers with amino-functional compounds.

[0018] For the purposes of this invention, ionogenic groups are understood to mean functional groups which are capable of forming ionic groups, for example by neutralization with a base.

[0019] Component A) can be any polyisocyanate that a person skilled in the art would use for this purpose. Polyisocyanates that are particularly suitable as component A) are the aliphatic polyisocyanates known per se to those skilled in the art with an average isocyanate functionality of ≥ 1.8 and ≤ 2.6. The term "aliphatic" also encompasses cycloaliphatic and / or araliphatic polyisocyanates.

[0020] The average isocyanate functionality is understood to be the average number of isocyanate groups per molecule.

[0021] Preferred polyisocyanates are those with a molecular weight range of 140 to 336 g / mol. These are particularly preferably selected from the group consisting of: 1,4-Diisocyanatobutane (BDI), 1,5-Pentane diisocyanate (PDI), 1,6-Diisocyanatohexane (HDI), 1,3-Bis(isocyanatomethyl)benzene (1,3-Xylylene diisocyanate, XDI), 1,4-Bis(isocyanatomethyl)benzene (1,4-Xylylene diisocyanate, XDI), 1,3-Bis(1-isocyanato-1-methyl-ethyl)benzene (TMXDI), 1,4-Bis(1-isocyanato-1-methyl-ethyl)benzene (TMXDI), 4-Isocyanatomethyl-1,8-octane diisocyanate (Trisisocyanatononane (TIN)), 2-Methyl-1,5-Diisocyanatopentane, 1,5-Diisocyanato-2,2-dimethylpentane, 2,2,4- or 2,4,4-Trimethyl-1,6-diisocyanatohexane, 1,10-Diisocyanatodecane and the cycloaliphatic diisocyanates 1,3- and1,4-Diisocyanatocyclohexane, 1,4-Diisocyanato-3,3,5-trimethylcyclohexane, 1,3-Diisocyanato-2(4)-methylcyclohexane, 1-Isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 1-Isocyanato-1-methyl-4(3)isocyanato-methylcyclohexane, 1,8-diisocyanato-p-menthane, 4,4'-diisocyanato-1,1'-bi(cyclohexyl), 4,4'-diisocyanato-3,3'-dimethyl-1,1'-bi(cyclohexyl), 4,4'-Diisocyanato-2,2',5,5'-tetramethyl-1,1'-bi(cyclohexyl), 4,4'- and / or 2,4'-diisocyanatodicyclohexylmethane, 4,4'-Diisocyanato-3,3'-dimethyldicyclohexylmethane, 4,4'-Diisocyanato-3,3',5,5'-tetramethyldicyclohexylmethane, 1,3-Diisocyanatoadamantane, and 1,3-Dimethyl-5,7-diisocyanatoadamantane or any mixtures of such isocyanates.The polyisocyanates selected from 1,4-butylene diisocyanate, 1,5-pentamethylene diisocyanate (PDI), 1,6-hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 2,2,4- and / or 2,4,4-trimethylhexamethylene diisocyanate, the isomeric bis-(4,4'-isocyanatocyclohexyl)methanes or mixtures thereof of any isomer content (H12-MDI), 1,4-cyclohexylene diisocyanate, 4-isocyanatomethyl-1,8-octane diisocyanate (nonane triisocyanate) and alkyl 2,6-diisocyanatohexanoates (lysine diisocyanates) with C1-C8 alkyl groups are very particularly preferred.

[0022] In addition to the polyisocyanates mentioned above, modified diisocyanates having an average isocyanate functionality ≥ 2 and ≤ 2.6, with uretdione, isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione or oxadiazinetrione structure as well as mixtures of these and / or the above can also be used proportionally.

[0023] Preferably, these are polyisocyanates or polyisocyanate mixtures of the type mentioned above with exclusively aliphatically or cycloaliphatically bound isocyanate groups or mixtures thereof and an average NCO functionality of the mixture of ≥ 1.8 and ≤ 2.6 and particularly preferably ≥ 2.0 and ≤ 2.4.

[0024] The organic polyisocyanate component A) particularly preferably contains an aliphatic or cycloaliphatic polyisocyanate selected from HDI, IPDI and / or H12-MDI or their modification products, very particularly preferably selected from HDI and / or IPDI.

[0025] In a particularly preferred variant, IPDI and HDI are present in the mixture as component A).

[0026] The weight ratio of IPDI:HDI is preferably in the range from 1.05 to 10, particularly preferably in the range from 1.1 to 5, and most preferably in the range from 1.1 to 1.5.

[0027] In a preferred embodiment, ≥ 5 and ≤ 40 wt.% of component A) and particularly preferably ≥ 10 and ≤ 35 wt.% of component A), in each case based on the total mass of the polyurethaneurea, are used to produce the polyurethaneurea used according to the invention.

[0028] In a further preferred embodiment, component H), an aliphatic polyisocyanate component with an average isocyanate functionality (average number of isocyanate groups per molecule) of > 2.6 and ≤ 4, preferably ≥ 2.8 and ≤ 3.8, is also used to produce the polyurethaneurea. Component H) is preferably used in a mixture with component A).

[0029] Particularly suitable as component H) are oligomeric diisocyanates having a functionality of > 2.6 and ≤ 4, preferably ≥ 2.8 and ≤ 3.8, with isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione, or oxadiazinetrione structures. H) most preferably contains isocyanurate structures.

[0030] The organic polyisocyanate component H) particularly preferably consists of an aliphatic or cycloaliphatic polyisocyanate oligomer based on HDI, IPDI and / or H12-MDI, very particularly preferably based on HDI.

[0031] The molar ratio of the NCO groups from component A) to component H) is preferably 100:0.5 to 100:50; particularly preferably 100:2 to 100:15 and very particularly preferably 100:3 to 100:8.

[0032] In a preferred embodiment, ≥ 0 and ≤ 10 wt.% of component H) and particularly preferably ≥ 0.1 and ≤ 3 wt.% of component H), in each case based on the total mass of the polyurethaneurea, are used to produce the polyurethaneurea used according to the invention.

[0033] The polymeric polyether polyols used according to the invention as component B) preferably have number-average molecular weights of ≥ 500 and ≤ 8000 g / mol, determined by gel permeation chromatography against polystyrene standard in tetrahydrofuran at 23°C, more preferably ≥ 400 and ≤ 6000 g / mol and particularly preferably ≥ 600 and ≤ 3000 g / mol and / or OH functionalities of preferably ≥ 1.5 and ≤ 6, more preferably ≥ 1.8 and ≤ 3, particularly preferably ≥ 1.9 and ≤ 2.1.

[0034] The term "polymeric" polyether polyols here means in particular that the polyols mentioned have at least three, preferably at least four interconnected repeating units.

[0035] For the purposes of this application, the number-average molecular weight is determined by gel permeation chromatography (GPC) in tetrahydrofuran at 23°C, unless otherwise stated. The procedure is according to DIN 55672-1: "Gel Permeation Chromatography, Part 1 - Tetrahydrofuran as Eluent" (SECurity GPC system from PSS Polymer Service, flow rate 1.0 ml / min; columns: 2×PSS SDV linear M, 8×300 mm, 5 µm; RID detector). Polystyrene samples of known molecular weight are used for calibration. The calculation of the number-average molecular weight is software-assisted. Baseline points and evaluation limits are defined according to DIN 55672 Part 1.

[0036] Suitable polyether polyols include, for example, the known addition products of styrene oxide, ethylene oxide, propylene oxide, butylene oxide, and / or epichlorohydrin to di- or polyfunctional starter molecules. Polyalkylene glycols, such as polyethylene, polypropylene, and / or polybutylene glycols, are particularly suitable, especially with the preferred molecular weights mentioned above. Suitable starter molecules include all compounds known from the prior art, such as water, butyldiglycol, glycerol, diethylene glycol, trimethylolpropane, propylene glycol, sorbitol, ethylenediamine, triethanolamine, and 1,4-butanediol.

[0037] Suitable poly(tetramethylene glycol) polyether polyols are obtainable, for example, by polymerization of tetrahydrofuran by cationic ring opening.

[0038] According to the invention, component B) contains or consists of a mixture of poly(tetramethylene glycol) polyether polyols, wherein the poly(tetramethylene glycol) polyether polyols differ in their number-average molecular weights.

[0039] In a particularly preferred embodiment, component B) contains a mixture of poly(tetramethylene glycol)polyether polyols I having a number-average molecular weight M n in a range of ≥ 400 and ≤ 1500 g / mol, particularly preferably in a range of ≥ 600 and ≤ 1200 g / mol, very particularly preferably in a range of 1000 g / mol and poly(tetramethylene glycol)polyether polyols II having a number-average molecular weight M n in a range of ≥ 1500 and ≤ 8000 g / mol, particularly preferably in a range of ≥ 1800 and ≤ 3000 g / mol, very particularly preferably 2000 g / mol.

[0040] The weight ratio of the poly(tetramethylene glycol) polyether polyols I to the poly(tetramethylene glycol) polyether polyols II is preferably in the range from 0.1 to 10, particularly preferably in the range from 0.2 to 10, very particularly preferably in the range from 1 to 6.

[0041] According to the invention, an amino-functional chain extender component C) having at least two isocyanate-reactive amino groups, containing at least one amino-functional compound C1) which has no ionic or ionogenic groups and one amino-functional compound C2) which has ionic or ionogenic groups, is used to produce the polyurethaneurea.

[0042] The amino-functional compounds of component C) are preferably selected from primary and / or secondary diamines. In particular, the amino-functional compounds C) comprise at least one diamine.

[0043] In a preferred embodiment of the product, the amino-functional component C) comprises at least one amino-functional compound C2) which has ionic and / or ionogenic groups.

[0044] In a further preferred embodiment of the invention, the amino-functional component C) comprises both amino-functional compounds C2) which have ionic and / or ionogenic groups and amino-functional compounds C1) which do not have an ionic or ionogenic group.

[0045] For example, organic di- or polyamines such as 1,2-ethylenediamine, 1,2- and 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, isophoronediamine (IPDA), isomer mixture of 2,2,4- and 2,4,4-trimethylhexamethylenediamine, 2-methylpentamethylenediamine, diethylenetriamine, 4,4-diaminodicyclohexylmethane and / or dimethylethylenediamine or mixtures of at least two thereof can be used as component C1).

[0046] Preferably, component C1) is selected from the group consisting of 1,2-ethylenediamine, bis(4-aminocyclohexyl)methane, 1,4-diaminobutane, IPDA, ethanolamine, diethanolamine and diethylenetriamine or a mixture of at least two thereof.

[0047] In a further preferred embodiment, component C1) contains > 75 mol%, particularly preferably ≥ 80 mol%, very particularly preferably ≥ 85 mol%, furthermore preferably ≥ 95 mol%, and furthermore preferably 100 mol% of 1,2-ethylenediamine or IPDA or a mixture of 1,2-ethylenediamine and IPDA, the sum of the two amines based on the total amount of C1) preferably being present in the stated ranges. Component C1) preferably contains > 75 mol%, particularly preferably ≥ 80 mol%, very particularly preferably ≥ 85 mol%, furthermore preferably ≥ 95 mol%, and furthermore preferably 100 mol% of 1,2-ethylenediamine.

[0048] The hydrophilizing component C2) preferably comprises at least one anionically hydrophilizing compound. Furthermore, the hydrophilizing component C2) preferably contains at least 80% by weight, or preferably at least 90% by weight, of an anionically hydrophilizing compound, based on the total weight of component C2). Particularly preferably, component C2) consists exclusively of anionically hydrophilizing compounds.

[0049] Suitable anionically hydrophilizing compounds contain at least one anionic or ionogenic group that can be converted into an anionic group. Furthermore, suitable anionically hydrophilizing compounds preferably have at least two amino groups, and particularly preferably two amino groups. Particularly preferably, the hydrophilizing component C2) comprises an anionically hydrophilizing compound that has or consists of at least one anionic or ionogenic group and at least two amino groups.

[0050] Suitable anionically hydrophilizing compounds as component C2), hereinafter also referred to as hydrophilizing agents C2), preferably contain a sulfonic acid or sulfonate group, particularly preferably a sodium sulfonate group. Suitable anionically hydrophilizing compounds as component C2) are, in particular, the alkali metal salts of mono- and diaminosulfonic acids. Examples of such anionic hydrophilizing agents are salts of 2-(2-aminoethylamino)ethanesulfonic acid, ethylenediamine-propyl- or -butylsulfonic acid, or 1,2- or 1,3-propylenediamine-β-ethylsulfonic acid, or mixtures of at least two thereof.

[0051] Particularly preferred anionic hydrophilizing agents C2) are those containing sulfonate groups as ionic groups and two amino groups, such as the salts of 2-(2-aminoethylamino)ethylsulfonic acid and 1,3-propylenediamine-β-ethylsulfonic acid. 2-(2-aminoethylamino)ethylsulfonic acid or its salts are very particularly preferably used as the anionic hydrophilizing agent C2).

[0052] Optionally, the anionic group in component C2) can also be a carboxylate or carboxylic acid group. Component C2) is then preferably selected from diaminocarboxylic acids. In this alternative embodiment, however, the carboxylic acid-based components C2) must be used in higher concentrations compared to those components C2) that carry sulfonate or sulfonic acid groups. Therefore, it is particularly preferred not to use hydrophilizing compounds that carry exclusively carboxylate groups as anionic groups of component C2) for the preparation of the polyurethaneurea.

[0053] In a preferred embodiment, the polyurethaneurea used according to the invention is prepared using a range of ≥ 0.1 and ≤ 10 wt.% of component C2) and particularly preferably a range of ≥ 0.5 and ≤ 4 wt.% of component C2), each based on the total mass of the polyurethaneurea.

[0054] For hydrophilization, mixtures of anionic hydrophilizing agents C2) and other hydrophilizing agents D) which are different from C2) can also be used.

[0055] Suitable further hydrophilizing agents D) are, for example, non-ionic hydrophilizing compounds D1) and / or hydroxy-functional ionic or ionogenic hydrophilizing agents D2). Component D) is preferably a non-ionic hydrophilizing component D1).

[0056] Suitable hydroxy-functional ionic or ionogenic hydrophilizing agents as component D2) are, for example, hydroxycarboxylic acids such as mono- and dihydroxycarboxylic acids, such as 2-hydroxyacetic acid, 3-hydroxypropanoic acid, 12-hydroxy-9-octadecanoic acid (ricinoleic acid), hydroxypivalic acid, lactic acid, dimethylolbutyric acid and / or dimethylolpropionic acid or mixtures of at least two thereof. Hydroxypivalic acid, lactic acid and / or dimethylolpropionic acid are preferred, with particular preference being given to dimethylolpropionic acid. It is preferred not to use hydroxy-functional ionic or ionogenic hydrophilizing agents D2), and particularly preferably not to use hydrophilizing agents which contain carboxylate and hydroxyl groups, such as, for example, dimethylolpropionic acid. The amount of hydroxy-functional ionic or ionogenic hydrophilizing agent D2) is preferably in a range from 0 to 1% by weight, or preferably in a range from 0 to 0.5% by weight.-%, based on the total mass of the polyurethaneurea contained in the polyurethaneurea.

[0057] Suitable non-ionically hydrophilizing compounds as component D1) include, for example, polyoxyalkylene ethers containing isocyanate-reactive groups, such as hydroxyl, amino, or thiol groups. Preference is given to monohydroxy-functional polyalkylene oxide polyether alcohols containing, on average, 5 to 70, preferably 7 to 55, ethylene oxide units per molecule, as are obtainable in a conventional manner by alkoxylation of suitable starter molecules (e.g., in Ullmann's Encyclopedia of Industrial Chemistry, 4th Edition, Volume 19, Verlag Chemie, Weinheim, pp. 31-38). These are either pure polyethylene oxide ethers or mixed polyalkylene oxide ethers, containing at least 30 mol%, preferably at least 40 mol%, of ethylene oxide units, based on all alkylene oxide units present.

[0058] Particularly preferred nonionic compounds are monofunctional mixed polyalkylene oxide polyethers containing 40 to 100 mol% ethylene oxide and 0 to 60 mol% propylene oxide units.

[0059] Suitable starter molecules for such non-ionic hydrophilic agents are, in particular, saturated monoalcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, the isomeric pentanols, hexanols, octanols and nonanols, n-decanol, n-dodecanol, n-tetradecanol, n-hexadecanol, n-octadecanol, cyclohexanol, the isomeric methylcyclohexanols or hydroxymethylcyclohexane, 3-ethyl-3-hydroxymethyloxetane or tetrahydrofurfuryl alcohol, diethylene glycol monoalkyl ethers, such as diethylene glycol monobutyl ether, unsaturated alcohols such as allyl alcohol, 1,1-dimethylallyl alcohol or olein alcohol, aromatic alcohols such as phenol, the isomeric cresols or methoxyphenols, araliphatic alcohols such as Benzyl alcohol, anise alcohol or cinnamyl alcohol, secondary monoamines such as dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, bis-(2-ethylhexyl)-amine,N-Methyl- and N-ethylcyclohexylamine or dicyclohexylamine, as well as heterocyclic secondary amines such as morpholine, pyrrolidine, piperidine, or 1H-pyrazole. Preferred starter molecules are saturated monoalcohols of the type mentioned above. Diethylene glycol monobutyl ether, methanol, or n-butanol are particularly preferred as starter molecules.

[0060] Alkylene oxides suitable for the alkoxylation reaction are, in particular, ethylene oxide and propylene oxide, which can be used in any order or in a mixture in the alkoxylation reaction.

[0061] In a preferred embodiment of the invention, the polyurethaneurea used according to the invention contains in a range of ≥ 0 and ≤ 20 wt.% of component D), preferably in a range of ≥ 0 and ≤ 10 wt.% of component D), and very particularly preferably in a range of ≥ 0 and ≤ 5 wt.% of component D), in each case based on the total mass of the polyurethaneurea. In a further preferred embodiment, component D) is not used to produce the polyurethaneurea.

[0062] As component E), polyols, in particular non-polymeric polyols, of the stated molecular weight range of 62 to 399 mol / g with up to 20 carbon atoms, such as ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,3-butylene glycol, cyclohexanediol, 1,4-cyclohexanedimethanol, 1,6-hexanediol, neopentyl glycol, hydroquinone dihydroxyethyl ether, bisphenol A (2,2-bis(4-hydroxyphenyl)propane), hydrogenated bisphenol A (2,2-bis(4-hydroxycyclohexyl)propane), trimethylolpropane, trimethylolethane, glycerol, pentaerythritol and any mixtures thereof with one another can be used.

[0063] In a preferred embodiment of the invention, the polyurethaneurea used according to the invention contains ≤ 10 wt.% of component E), preferably ≤ 5 wt.%, particularly preferably 0 wt.% of component E), in each case based on the total mass of the polyurethaneurea. The polyurethaneurea preferably contains component E) in a range from 0.1 to 10 wt.%, preferably in a range from 0.2 to 8 wt.%, preferably in a range from 0.1 to 5 wt.%, in each case based on the total mass of the polyurethaneurea. In a further preferred embodiment, component E) is not used to produce the polyurethaneurea.

[0064] In a preferred embodiment, the polyurethaneurea used according to the invention is used in a range of ≥ 0.5 and ≤ 20 wt.% of the sum of components C1) and optionally E) and particularly preferably in a range of ≥ 1 and ≤ 15 wt.% of the sum of components C1) and optionally E), in each case based on the total mass of the polyurethaneurea.

[0065] As component F), other polymeric polyols which are different from B) can be used.

[0066] Examples are polymeric polyols which do not fall under the definition of B) because they are not polyether polyols - for example the polyester polyols, polyacrylate polyols, polyurethane polyols, polycarbonate polyols, polyester polyacrylate polyols, polyurethane polyacrylate polyols, polyurethane polyester polyols, polyurethane polycarbonate polyols and polyester polycarbonate polyols which are known per se in polyurethane coating technology.

[0067] Component F) preferably does not comprise polymeric polyols containing ester groups, in particular polyester polyols.

[0068] According to the invention, components B) and F) together contain ≤ 30 wt. %, preferably ≤ 10 wt. %, and particularly preferably ≤ 5 wt. %, of component F), based on the total mass of components B) and F). Very particularly preferably, component F) is not used for the preparation of the polyurethaneurea.

[0069] In a preferred embodiment, the polyurethaneurea used according to the invention is prepared in a range of ≥ 55 and ≤ 90 wt.% of the sum of components B) and optionally F) and particularly preferably in a range of ≥ 60 and ≤ 85 wt.% of the sum of components B) and optionally F), in each case based on the total mass of the polyurethaneurea.

[0070] Component G) comprises compounds which have exactly one isocyanate-reactive group or compounds which have more than one isocyanate-reactive group, whereby only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the chosen reaction conditions.

[0071] The isocyanate-reactive groups of component G) can be any functional group that can react with an isocyanate group, such as hydroxyl groups, thiol groups or primary and secondary amino groups.

[0072] Isocyanate-reactive groups within the meaning of the invention are primary or secondary amino groups that react with isocyanate groups to form urea groups. In addition to the amino group, the compounds of component G) may also contain other, in principle, isocyanate-reactive groups, such as OH groups, whereby only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the chosen reaction conditions. This can be achieved, for example, by reacting corresponding amino alcohols at relatively low temperatures, for example, at 0 to 60°C, preferably at 20 to 40°C. Preferably, the reaction is carried out in the absence of catalysts that would catalyze the reaction of isocyanate groups with alcohol groups.

[0073] Examples of suitable compounds of component G) are primary / secondary amines, such as methylamine, ethylamine, propylamine, butylamine, octylamine, laurylamine, stearylamine, isononyloxypropylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, N-methylaminopropylamine, diethyl(methyl)aminopropylamine, morpholine, piperidine, diethanolamine, 3-amino-1-methylaminopropane, 3-amino-1-ethylaminopropane, 3-amino-1-cyclohexylaminopropane, 3-amino-1-methylaminobutane, ethanolamine, 3-aminopropanol or neopentanolamine.

[0074] Suitable monofunctional compounds are also ethanol, n-butanol, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, dipropylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monobutyl ether, 2-ethylhexanol, 1-octanol, 1-dodecanol, 1-hexadecanol.

[0075] In a preferred embodiment, ≥ 0.1 and ≤ 20 wt.% of component G) and particularly preferably ≥ 0.3 and ≤ 10 wt.% of component G), in each case based on the total mass of the polyurethaneurea, are used to produce the polyurethaneurea used according to the invention.

[0076] According to the invention, component H) is used and the molar ratio of component G) to component H) is preferably 5:1 to 1:5, particularly preferably 1.5:1 to 1:4 and very particularly preferably 1:1 to 1:3.

[0077] In a preferred embodiment, components A) to H) are used in the following amounts to prepare the polyurethaneureas used according to the invention, the individual amounts always adding up to 100% by weight: 5 to 40 wt.% component A), 55 to 90 wt.% sum of components B) and optionally F), 0.5 to 20 wt.% sum of components C1) and optionally E), 0.1 to 10 wt.% component C2), 0 to 20 wt.% component D), 0.1 to 20 wt.% of component G) and 0 to 10 wt.% component H).

[0078] In a particularly preferred embodiment, components A) to H) are used in the following amounts to prepare the polyurethaneureas used according to the invention, the individual amounts always adding up to 100% by weight: 10 to 35 wt.% component A), 60 to 85 wt.% sum of components B) and optionally F), 1 to 15 wt.% sum of components C1) and optionally E), 0.5 to 4 wt.% component C2), 0 to 10 wt.% component D), 0.3 to 10 wt.% of component G) and 0.1 to 3 wt.% component H).

[0079] In a particularly preferred embodiment of the invention, the contact adhesive product comprises a polyurethaneurea obtainable by reacting at least A) an aliphatic polyisocyanate component, which is a mixture of IPDI and HDI, B) a polymeric polyether-polyol component, which is a mixture of at least two poly(tetramethylene glycol)polyether polyols and wherein the poly(tetramethylene glycol)polyether polyols differ in their number-average molecular weights, C) an amino-functional chain extender component with two isocyanate-reactive primary and / or secondary amino groups, containing at least one amino-functional compound C1) which has no ionic or ionogenic groups and / or one amino-functional compound C2) which has ionic or ionogenic groups, D) optionally further hydrophilizing components which are different from C2), which are non-ionically hydrophilizing components D1), E) optionally hydroxy-functional compounds with a molecular weight of 62 to 399 mol / g, F) ​​optionally further polymeric polyols,which are different from B), G) a compound which has exactly one isocyanate-reactive group, or a compound which has more than one isocyanate-reactive group, where only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the chosen reaction conditions, where the isocyanate-reactive group is a primary and / or secondary amino and / or hydroxy group and H) an aliphatic polyisocyanate component with an average isocyanate functionality of > 2.6 and ≤ 4, where component H) consists of an aliphatic or cycloaliphatic polyisocyanate oligomer with isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione or oxadiazinetrione structure, based on HDI, IPDI and / or H12-MDI, wherein components B) and F) together contain ≤ 30 wt.% of component F), based on the total mass of components B) and F).

[0080] The polyurethaneurea used according to the invention is most preferably obtainable by reacting exclusively components A) to H). No further components are then used to prepare the polyurethaneurea.

[0081] The number-average molecular weight of the polyurethaneureas preferably used according to the invention is preferably from ≥ 2000 to ≤ 300000 g / mol, preferably from ≥ 5000 to ≤ 150000 g / mol.

[0082] The polyurethaneurea used according to the invention is preferably amorphous and has a Tg ≤ - 25 °C, particularly preferably ≤ - 50 °C and very particularly preferably ≤ - 70 °C.

[0083] Amorphous in the sense of this invention means that the polyurethaneurea forms no or only such small crystalline components in the temperature range specified in the measurement method described below that only one or more glass transition points T g can be found by means of the described DSC measurements, but no melting ranges with a melting enthalpy ≥ 20J / g in the temperature range specified.

[0084] The glass transition temperature T g is determined in the context of this invention by means of dynamic differential calorimetry in accordance with DIN EN 61006, method A, using a DSC device that is calibrated to determine T g with indium and lead, and three immediately successive runs of heating from - 100°C to +150°C, at a heating rate of 20 K / min, followed by cooling at a cooling rate of 320 K / min are carried out, and the third heating curve is used to determine the values, and T g is determined as the temperature at half the height of a glass transition step.

[0085] If the polyurethaneurea is in the form of a dispersion, special sample preparation procedures are required for DSC measurements. When determining the glass transition temperature T g of dispersions using DSC, the T g of the polymer can be masked by the calorific effects of the dispersant (water, neutralizing agent, emulsifiers, cosolvents, etc.) or significantly reduced due to miscibility with the polymer. Therefore, the dispersant is preferably completely removed by suitable drying before the DSC measurement, because even small residual amounts of dispersant act as a plasticizer and can thereby lower the glass transition temperature. The dispersion is therefore preferably doctor-coated onto a glass plate with a wet film thickness of 100 µm, flashed off, and then gently dried for two days in a drying box at room temperature and 0% relative humidity (RH).After this sample preparation, a wide endothermic evaporation range of residual moisture in the film can still be detected during the first heating of the DSC measurement. To obtain the determined values ​​as free as possible from such influences, the third heating curve is evaluated.

[0086] The polyurethaneurea used according to the invention to produce the product is preferably present in a physiologically acceptable medium. The medium is particularly preferably water, and the polyurethaneurea is most preferably present as an aqueous dispersion. Water generally forms, along with other optionally present liquid media, such as solvents, the main component (>50 wt.%) of the dispersing medium, based on the total amount of the liquid dispersing medium, and may also be the sole liquid dispersing medium.

[0087] The product according to the invention itself contains the polyurethane urea itself, which contains no or only residual amounts of this medium.

[0088] Preferably, the polyurethaneurea used is therefore dispersible in water, which in the context of this invention means that the polyurethaneurea can form a sedimentation-stable dispersion in water, in particular deionized water, at 23°C.

[0089] The polyurethaneureas used according to the invention are preferably obtainable by preparing isocyanate-functional polyurethane prepolymers a) from components A), B) and optionally D) and / or C2), and optionally the compounds E) and / or H) (step a) and subsequently reacting their free NCO groups wholly or partly with the amino-functional chain extender component C), and component G) and optionally components D) and H) (step b)).

[0090] Whereby, if component H) is only used in step b), it is preferably added before the addition of component C) and reacted with the prepolymer a).

[0091] In a preferred embodiment of the invention, in step b) the reaction with one or more diamines (component C) takes place with chain extension, wherein the monofunctional component G) is also added as a chain terminator for molecular weight control.

[0092] Components A) to H) are defined as above. The preferred embodiments mentioned above also apply.

[0093] Preferably, in step b) of the reaction of prepolymer a) to produce the polyurethaneurea, a mixture of components C1), C2), and G) is reacted. By using component C1), a high molecular weight can be achieved without increasing the viscosity of the previously prepared isocyanate-functional prepolymer to an extent that would impede processing. By using the combination of components C1), C2), and G), an optimal balance between hydrophilicity and chain length can be achieved.

[0094] The polyurethane prepolymer a) used according to the invention preferably has terminal isocyanate groups, i.e., the isocyanate groups are located at the chain ends of the prepolymer. Particularly preferably, all chain ends of the prepolymer have isocyanate groups.

[0095] The hydrophilicity of the prepolymer can be controlled via the hydrophilizing components C2) and / or D). Of course, other components also play a role in the hydrophilicity of the prepolymer, especially the hydrophilicity of component B).

[0096] Preferably, the isocyanate-functional polyurethane prepolymers a) are water-insoluble and not dispersible in water.

[0097] In the context of the invention, the term "water-insoluble, non-water-dispersible polyurethane prepolymer" means, in particular, that the water solubility of the prepolymer used according to the invention at 23°C is less than 10 g / liter, more preferably less than 5 g / liter, and that the prepolymer does not produce a sedimentation-stable dispersion in water, especially deionized water, at 23°C. In other words, the prepolymer settles when attempted to be dispersed in water. The water insolubility or lack of dispersibility in water refers to deionized water without the addition of surfactants.

[0098] Furthermore, the polyurethane prepolymer a) used according to the invention preferably contains essentially neither ionic nor ionogenic groups (capable of forming ionic groups). In the context of the present invention, this means that the proportion of ionic and / or ionogenic groups, such as in particular anionic groups such as carboxylate or sulfonate, or cationic groups, is less than 15 milliequivalents per 100 g of polyurethane prepolymer a1), preferably less than 5 milliequivalents, particularly preferably less than 1 milliequivalent, and most particularly preferably less than 0.1 milliequivalents per 100 g of polyurethane prepolymer a).

[0099] In the case of acidic ionic and / or ionogenic groups, the acid number of the prepolymer is advantageously below 30 mg KOH / g prepolymer, preferably below 10 mg KOH / g prepolymer. The acid number indicates the mass of potassium hydroxide in mg required to neutralize 1 g of the sample to be analyzed (measured according to DIN EN ISO 211). The neutralized acids, i.e., the corresponding salts, naturally have no or a reduced acid number. According to the invention, the acid number of the corresponding free acid is decisive here.

[0100] The water-insoluble, non-water-dispersible, isocyanate-functional polyurethane prepolymers a) are preferably exclusively obtainable from components A), B) and optionally D), E) and / or H).

[0101] The components are defined as above. The preferred embodiments mentioned above also apply.

[0102] Consequently, in this embodiment, it is preferred not to use any ionically hydrophilizing components C2) or D2) to produce prepolymer a). Component G) is also not added in this step. The hydrophilizing agents D1) are preferably used in amounts such that the prepolymer is nevertheless water-insoluble and non-water-dispersible. Particular preference is given to using ≤ 10 wt.% of component D1), very particular preference ≤ 5 wt.%, and furthermore preferably ≤ 2 wt.% of component D1), each based on the total mass of the polyurethaneurea. Further preferably, component D1) is not used to produce prepolymer a).

[0103] For this embodiment of the invention, component B) contains neither ionic nor ionogenic groups. Furthermore, in this embodiment of the invention, component B) preferably uses only polyether polyols, in particular polyalkylene oxide ethers, which contain ≤ 10 mol% of ethylene oxide units, based on all alkylene oxide units present, and preferably no ethylene oxide units.

[0104] The polyurethaneureas preferably used in this embodiment of the invention therefore have ionic or ionogenic groups, preferably anionic groups. These anionic groups are introduced into the polyurethaneureas used according to the invention via the hydrophilizing component C2) used in step b). The polyurethaneureas used according to the invention optionally additionally have non-ionic components for hydrophilization.

[0105] Particularly preferably, the polyurethaneureas used according to the invention contain exclusively sulfonate groups for hydrophilization, which are introduced into the polyurethaneurea in step b) via corresponding diamines as component C2).

[0106] In an alternative, less preferred embodiment of the invention, the prepolymers a) used to prepare the polyurethaneurea according to the invention are water-soluble or water-dispersible. In this embodiment, the hydrophilizing component D) and / or C2) is used in the preparation of prepolymer a) in an amount sufficient to make the prepolymer water-soluble or water-dispersible. Prepolymer a) preferably has ionic or ionogenic groups.

[0107] Suitable hydrophilizing components D) and C2) for this embodiment of the invention are the compounds mentioned above for D) and C2). Preferably, at least the compounds mentioned above under D1) and / or C2) are used as hydrophilizing components.

[0108] The polyurethaneureas used to prepare the products according to the invention are preferably dispersed in water before, during, or after step b), particularly preferably during or after step b). A dispersion of the polyurethaneureas is thus obtained.

[0109] The production of polyurethaneurea dispersions can be carried out in one or more stages in a homogeneous phase or, in the case of multi-stage reactions, partially in a dispersed phase. After the production of prepolymer a), a dispersion, emulsification, or dissolution step preferably follows. This is followed, if necessary, by a further polyaddition or modification in a dispersed phase. The solvent or dispersant suitable for the respective prepolymer, such as water or acetone or mixtures thereof, is selected.

[0110] Any known prior art process, such as prepolymer mixing processes, acetone processes, or melt dispersion processes, can be used. The acetone process is preferred.

[0111] For production by the acetone process, components B), optionally D) and E), and the polyisocyanate component A), optionally in combination with component H), are usually introduced in whole or in part to produce an isocyanate-functional polyurethane prepolymer and optionally diluted with a solvent that is miscible with water but inert towards isocyanate groups and heated to temperatures in the range of 50 to 120°C. Catalysts known in polyurethane chemistry can be used to accelerate the isocyanate addition reaction.

[0112] Suitable solvents are the usual aliphatic, keto-functional solvents such as acetone and 2-butanone, which can be added not only at the beginning of the preparation but also in portions later if necessary. Acetone and 2-butanone are preferred, with acetone being particularly preferred. The addition of other solvents without isocyanate-reactive groups is also possible, but not preferred.

[0113] Subsequently, the components of A), B) and, if applicable, H), D) and E) that were not added at the beginning of the reaction can be added.

[0114] In the preparation of the polyurethane prepolymer from A), B) and optionally H), D) and E), the molar ratio of isocyanate groups to isocyanate-reactive groups is preferably 1.05 to 3.5, particularly preferably 1.1 to 3.0 and very particularly preferably 1.1 to 2.5.

[0115] The conversion of components A), B) and optionally H), D), and E) to the prepolymer can be partial or complete, but preferably complete. Polyurethane prepolymers containing free isocyanate groups can thus be obtained in bulk or in solution.

[0116] If ionogenic groups, such as carboxyl groups, are present in the prepolymer, these can be converted into ionic groups in a further step by neutralization.

[0117] In the neutralization step for the partial or complete conversion of potentially anionic groups into anionic groups, bases such as tertiary amines, e.g. trialkylamines having 1 to 12, preferably 1 to 6, C atoms, particularly preferably 2 to 3 C atoms in each alkyl radical or very particularly preferably alkali metal bases such as the corresponding hydroxides can be used.

[0118] Inorganic bases such as aqueous ammonia solution or sodium or potassium hydroxide are preferably used as neutralizing agents, sodium hydroxide and potassium hydroxide being particularly preferred.

[0119] The amount of base is preferably between 50 and 125 mol%, particularly preferably between 70 and 100 mol%, of the amount of acid groups to be neutralized. Neutralization can also occur simultaneously with dispersion, in which case the dispersion water already contains the neutralizing agent.

[0120] Following neutralization, in a further process step, if not yet done or only partially done, the resulting prepolymer is dissolved using aliphatic ketones such as acetone or 2-butanone.

[0121] During chain extension / termination in step b), components C), G), and optionally D) are reacted with the remaining isocyanate groups of the prepolymer. Chain extension / termination is preferably carried out before dispersion in water.

[0122] Suitable components C) for chain extension and G) for chain termination are already listed above. The preferred embodiments mentioned above also apply analogously.

[0123] If anionic hydrophilizing agents according to definition C2) with NH 2 or NH groups are used for chain extension, the chain extension of the prepolymers in step b) preferably takes place before dispersion in water.

[0124] The equivalent ratio of NCO-reactive groups of the compounds used for chain extension and chain termination to free NCO groups of the prepolymer is generally between 40 and 150%, preferably between 50 and 110%, particularly preferably between 60 and 100%.

[0125] The components C1), C2) and G) can optionally be used in water- or solvent-diluted form in the process according to the invention individually or in mixtures, whereby in principle any order of addition is possible.

[0126] If water or organic solvents are used as diluents in step b), the respective diluent content in the components C1), C2) and G) used is preferably 40 to 95 wt.%.

[0127] Dispersal preferably occurs after chain extension and chain termination. For this purpose, the polyurethane polymer dissolved (e.g., in acetone) and reacted with the amine is either added to the dispersion water, optionally under strong shear, such as vigorous stirring, or, conversely, the dispersion water is stirred into the chain-extended polyurethane polymer solutions. The water is preferably added to the dissolved polyurethane polymer.

[0128] The solvent still present in the dispersions after the dispersion step is usually removed by distillation. Removal during the dispersion step is also possible.

[0129] The resulting aqueous polyurethaneurea dispersions preferably have a content of volatile organic compounds (VOCs), such as volatile organic solvents, of less than 10 wt. %, more preferably less than 3 wt. %, and even more preferably less than 1 wt. %, based on the aqueous polyurethaneurea dispersion. VOCs in the context of this invention are, in particular, organic compounds with an initial boiling point of at most 250°C at a standard pressure of 101.3 kPa.

[0130] In the context of the present invention, the content of volatile organic compounds (VOC) is determined in particular by gas chromatographic analysis.

[0131] The polyurethane urea is preferably used as an aqueous dispersion to produce the product.

[0132] The pH of the aqueous polyurethane dispersions used according to the invention is typically less than 9.0, preferably less than 8.5 and particularly preferably between 5.5 and 8.0.

[0133] In order to achieve good sedimentation stability, the number-average particle size of the special polyurethaneurea dispersions is preferably less than 750 nm, particularly preferably less than 500 nm, determined by laser correlation spectroscopy after dilution with deionized water (instrument: Malvern Zetasizer 1000, Malvern Inst. Limited).

[0134] The solids content of the polyurethaneurea dispersions is preferably 10 to 70 wt.%, particularly preferably 20 to 60 wt.%, and most preferably 40 to 60 wt.%. The solids contents are determined by heating a weighed sample to 125°C until constant weight is reached. At constant weight, the solids content is calculated by reweighing the sample.

[0135] These polyurethaneurea dispersions preferably contain less than 5% by weight, particularly preferably less than 0.2% by weight, of unbound organic amines, based on the mass of the dispersions.

[0136] The polyurethaneurea dispersions used to produce the products according to the invention preferably have a viscosity of ≥ 1 and ≤ 10,000 mPa s, particularly preferably ≥ 10 and ≤ 5,000 mPa s, and very particularly preferably ≥ 100 and ≤ 4,000 mPa s at 23°C and a constant shear rate of 10 s -1<. The viscosity is determined as described in the methods section.

[0137] Furthermore, the contact adhesive product according to the invention comprises a substrate.

[0138] Typically, suitable textiles with sufficient elasticity and suitable mechanical properties are used as substrates.

[0139] Textile fabrics are preferred as substrates. Fibrous materials with a non-smooth surface are particularly preferred as substrates for the polyurethaneureas used according to the invention. Textile fabrics within the meaning of the present invention include, for example, woven fabrics, knitted fabrics, braids, loops, knits, bonded and unbonded nonwovens. Preference is given to braids, in particular those made of warp and weft threads, knitted fabrics, in particular creped knitted fabrics, or nonwovens.

[0140] The textile fabrics can be composed of synthetic, natural fibers and / or mixtures thereof. Examples of natural fibers are cellulose, cotton, linen, and chemically modified fibers thereof. Examples of synthetic fibers are polyamide, polyester, etc. In principle, textiles made of any fiber are suitable for the process according to the invention. Mixtures of different fibers are also suitable. Particular preference is given to using a small proportion, in particular between 1 and 10% by weight, of an elastic fiber; the use of elastane is very particularly preferred here. The polyurethaneureas used according to the invention allow the substrates to be treated or finished in all conventional ways, preferably by coating or bonding the fibers to one another or substrates to one another.

[0141] Preferred substrates are products or nonwovens made of synthetic fibers, cellulose, or cotton. Particularly preferred are nonwovens, creped knits, or braids based on polyester or polyamide or their blends with cotton, or preferably cellulose fibers, which contain a proportion of highly elastic fibers of synthetic polymers (e.g., elastane or spandex) of 1 to 10 wt.%.

[0142] These fabrics preferably have basis weights of 20 to 600 gsm (grams per m 2< ), more preferably 25 to 300 gsm and most preferably 28 to 80 gsm.

[0143] Substrates are preferably used in the form of continuous bandages, wraps, or rolls. Elastic bandages with an elongation range of 30 to 500%, particularly preferably 60 to 250%, and most preferably 120 to 200%, determined according to DIN 53835 Part 2 (Determination of the tensile elastic behavior of textiles by repeated tensile stress between constant yield points (total elongation)), are preferred as substrates. Furthermore, the substrates preferably have a maximum tensile strength of 100 to 500 N, particularly preferably 120 to 350 N, determined according to DIN EN ISO 13934-1 using a strip tensile test.

[0144] Long-stretch bandages with an elongation range of 120 to 200% and a maximum tensile strength of 120 to 350 N are particularly preferred. The substrates used preferably have a coarse, rough, not completely closed surface. This can be defined by the air permeability in the unstretched state. Air permeabilities of > 200 l / m 2 < s are preferred, particularly preferred ≥ 1000 l / m 2 < s, and especially preferred ≥ 3000 l / m 2 < s. The air permeability of the substrates is determined according to DIN EN ISO 9237.

[0145] In a preferred embodiment of the invention, the polyurethaneurea covers at least one surface of the substrate; more preferably, the polyurethaneurea covers two opposite surfaces of the substrate (front and back) at the surface. Most preferably, the polyurethaneurea covers the surfaces uniformly.

[0146] It is possible that the substrate is impregnated with the polyurethane urea over its entire surface and thickness, but preferably the coating remains on the surface of the substrate and does not fully penetrate into its interior (bulk) or the fibers themselves.

[0147] The contact-adhesive products according to the invention are preferably products that are applied to the human body. The contact-adhesive products are particularly preferably used in medical fields, such as sports medicine, trauma surgery, or orthopedics, both for the treatment and prevention of bone, joint, or muscle injuries, or for the protection and covering of skin or skin injuries. Other preferred applications are bandages for compression therapy and the fixation of non-adhesive wound dressings (as "secondary dressings").

[0148] According to the invention, the contact-adhesive product is preferably a plaster, a dressing, a tape or a bandage or at least a component of these end products.

[0149] In the context of this invention, tape is understood to mean, in particular, an adhesive bandage which is used in medical fields for both the treatment and the prevention of bone, joint or muscle injuries.

[0150] Another object of the invention is a process for producing a contact adhesive product according to the invention comprising the steps I) applying the polyurethaneurea to the substrate in the form of an aqueous polyurethaneurea dispersion and II) thermally drying the treated substrate at temperatures ≥ 20°C and ≤ 200°C.

[0151] To apply the polyurethaneurea in step I, it is mixed in the form of a polyurethaneurea dispersion, preferably with additives, and particularly preferably without bubbles. The resulting composition is referred to below as the polyurethaneurea composition. A polyurethaneurea composition comprising the polyurethaneurea in the form of an aqueous dispersion and other additives is preferably used to produce the contact-adhesive product.

[0152] Of course, the viscosity of the polyurethaneurea dispersion can be adjusted to the required conditions by thinning or thickening, or a combination of both, to achieve the desired application thickness. Thickeners can be used as additives. Typical thickeners are soluble polymers based on polyacrylate or polyurethane, as known from the prior art. Thickeners based on polyurethane polymers are preferred. Common solvents, but preferably water, can be used to dilute the polyurethaneurea dispersion.

[0153] Furthermore, adhesion promoters can be used as additives to adjust the stickiness of the products. Adhesive enhancers (tackifiers) can be any additive known in the art. Examples include: water-miscible, mono-, di-, and multifunctional hydroxy compounds, preferably aliphatic, such as glycerol, ethylene glycol, propylene glycol, di-, tri-, and tetraethylene glycol, TMP, particularly preferably glycerol and triethylene glycol; short-chain polyethylene oxides such as PEG 200, PEG 300, PEG 400; rosin esters; copolymers based on styrene and acrylic acid esters or phenol ethers; or mixtures of the compounds mentioned.

[0154] Furthermore, it may be advantageous to regulate surface stickiness, which can lead to blocking of the bandage on the roll, by adding fillers as additives. These can be silica gel, silicates, talc, magnesia, calcite, urea and its derivatives, or other powdered solids, especially those that can be homogeneously incorporated into the polyurethane urea dispersion. Liquid additives can also be used to prevent blocking, for example, oil-based systems, preferably silicone-containing systems.

[0155] Typical other suitable additives are surface additives such as wetting agents, dyes, and / or flow control agents. The polyurethaneurea composition may also contain any other additives known to the person skilled in the art for the respective application.

[0156] The application to the substrate in step I) can generally be carried out using all known application techniques, in particular by means of a doctor blade, dipping bath, squeegee (or roller mill, technical term: squeegee), printing or spraying, with dipping, spraying and squeegee being preferred and spraying and squeegee being particularly preferred.

[0157] During application by the squeegee roller, the polyurethaneurea composition is preferably applied to the rollers, whose spacing and contact pressure have been optimized to achieve the desired layer thickness. The textile substrate can then be passed through the rollers, with the polyurethaneurea composition being applied to the textile in the specified amount. This preferably results in a coating on both sides. It is particularly preferred if the application can be carried out in one or two passes through the squeegee rollers, particularly preferably in a single pass.

[0158] For doctor blade application, the substrate can be pre-fixed in a clamping device, and then the doctor blade with the dispersion in front of it can be moved manually or automatically over the substrate, evenly distributing the dispersion. Coating can also be performed using a typical roll-to-roll coating system with a doctor blade, in which the substrate is continuously coated.

[0159] In the spraying process, the substrate is preferably clamped in a frame and sprayed with the dispersion from a spray gun on one or both sides. Application can be carried out manually in one or more cross-coatings or via a continuous roll-to-roll spray system.

[0160] In the dipping process, the substrate preferably passes through a dispersion bath containing the polyurethaneurea composition, thereby becoming wetted with it. The applied layer thickness can be controlled by the residence time in the bath, the concentration (or solids content) of the polyurethaneurea composition, and its viscosity. A stripping roller or a pair of squeegee rollers can be used to remove excess polyurethaneurea composition. Preferably, both sides are coated in a single pass.

[0161] After applying the polyurethaneurea composition to the substrate, preferably by one of the methods described above, the coating is dried in step II). Drying is carried out by thermal drying at temperatures between 20°C and 200°C, preferably between 40°C and 150°C, and particularly preferably between 60°C and 120°C. Thermal drying can be replaced or supported by IR or microwave drying.

[0162] When applying the polyurethaneurea composition to the substrate, at least one surface of the substrate is preferably coated; more preferably, two opposite surfaces of the substrate (front and back) are coated. Particularly, the coating with the polyurethaneurea composition is uniform.

[0163] Impregnation of the substrate with the polyurea composition over its entire surface and thickness is possible. However, the polyurethaneurea composition preferably remains on the surface of the substrate and does not fully penetrate its interior (bulk) or the fibers themselves.

[0164] Another object of the invention is a polyurethaneurea which is obtainable by reacting at least A) an aliphatic polyisocyanate component with an average isocyanate functionality of ≥ 1.8 and ≤ 2.6, B) a polymeric polyether-polyol component which contains or consists of a mixture of poly(tetramethylene glycol)polyether polyols, wherein the poly(tetramethylene glycol)polyether polyols differ in their number-average molecular weights, C) an amino-functional chain extender component with at least 2 isocyanate-reactive amino groups, containing at least one amino-functional compound C1) which has no ionic or ionogenic groups and one amino-functional compound C2) which has ionic or ionogenic groups, D) optionally further hydrophilizing components which are different from C2), E) optionally hydroxy-functional compounds with a molecular weight of 62 to 399 mol / g, F) ​​optionally further polymeric polyols which are different from B) G) a compound,which has exactly one isocyanate-reactive group, or a compound which has more than one isocyanate-reactive group, where only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the chosen reaction conditions and H) an aliphatic polyisocyanate component with an average isocyanate functionality of > 2.6 and ≤ 4, , wherein components B) and F) together contain ≤ 30 wt.% of component F), based on the total mass of components B) and F) and components G) and H) are present in a molar ratio of 5:1 to 1:5 to one another.

[0165] According to the invention, the molar ratio of component G) to component H) is 5:1 to 1:5, particularly preferably 1.5:1 to 1:4 and very particularly preferably 1:1 to 1:3.

[0166] For components A) to H), the definitions and preferred embodiments mentioned above for the polyurethaneurea contained in the product according to the invention apply analogously.

[0167] Particularly preferred component A) is isophorone diisocyanate and / or hexamethylene diisocyanate.

[0168] According to the invention, component B) contains or consists of a mixture of poly(tetramethylene glycol) polyether polyols, wherein the poly(tetramethylene glycol) polyether polyols differ in their number-average molecular weights.

[0169] According to the invention, component C) contains at least one amino-functional compound C1) which has no ionic or ionogenic groups and one amino-functional compound C2) which has ionic or ionogenic groups.

[0170] Also particularly preferably, component D) comprises non-ionic hydrophilizing components.

[0171] Particularly advantageous embodiments of the invention also result from the combinations of the features mentioned above as being particularly preferred.

[0172] In a preferred embodiment, components A) to H) are used in the following amounts to prepare the polyurethaneureas used according to the invention, the individual amounts always adding up to 100% by weight: 5 to 40 wt.% component A), 55 to 90 wt.% sum of components B) and optionally F), 0.5 to 20 wt.% sum of components C1) and optionally E), 0.1 to 10 wt.% component C2), 0 to 20 wt.% component D), 0.1 to 20 wt.% of component G) and 0 to 10 wt.% component H).

[0173] In a further preferred embodiment, components A) to H) are used in the following amounts to prepare the polyurethaneureas used according to the invention, the individual amounts always adding up to 100% by weight: 10 to 35 wt.% component A), 60 to 85 wt.% sum of components B) and optionally F), 1 to 15 wt.% sum of components C1) and optionally E), 0.5 to 4 wt.% component C2), 0 to 10 wt.% component D), 0.3 to 10 wt.% of component G) and 0.1 to 3 wt.% component H).

[0174] In a particularly preferred embodiment of the invention, the contact adhesive product comprises a polyurethaneurea which is obtainable by reacting at least A) an aliphatic polyisocyanate component, which is a mixture of IPDI and HDI, B) a polymeric polyether-polyol component, which is a mixture of at least two poly(tetramethylene glycol)polyether polyols and wherein the poly(tetramethylene glycol)polyether polyols differ in their number-average molecular weights, C) an amino-functional chain extender component with two isocyanate-reactive primary and / or secondary amino groups, containing at least one amino-functional compound C1) which has no ionic or ionogenic groups and / or one amino-functional compound C2) which has ionic or ionogenic groups, D) optionally further hydrophilizing components which are different from C2), which are non-ionically hydrophilizing components D1), E) optionally hydroxy-functional compounds with a molecular weight of 62 to 399 mol / g, F) ​​optionally further polymeric polyols,which are different from B), G) a compound which has exactly one isocyanate-reactive group, or a compound which has more than one isocyanate-reactive group, where only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the chosen reaction conditions, where the isocyanate-reactive group is a primary and / or secondary amino and / or hydroxy group and H) an aliphatic polyisocyanate component with an average isocyanate functionality of > 2.6 and ≤ 4, where component H) consists of an aliphatic or cycloaliphatic polyisocyanate oligomer with isocyanurate, urethane, allophanate, biuret, iminooxadiazinedione or oxadiazinetrione structure, based on HDI, IPDI and / or H12-MDI, wherein components B) and F) together contain ≤ 30 wt.% of component F), based on the total mass of components B) and F). and components G) and H) are present in a molar ratio of 1:1 to 1:3 to one another.

[0175] The polyurethaneurea according to the invention is most preferably obtainable by reacting exclusively components A) to H). No further components are then used to prepare the polyurethaneurea.

[0176] The polyurethaneureas according to the invention are preferably linear molecules, but can alternatively also be branched.

[0177] The number-average molecular weight of the polyurethaneureas preferably used according to the invention is preferably from ≥ 2000 to ≤ 300000 g / mol, preferably from ≥ 5000 to ≤ 150000 g / mol.

[0178] The polyurethaneurea according to the invention is preferably amorphous and has a T g of ≤ - 25 °C, or preferably of ≤ - 50 °C, or preferably of ≤ - 70 °C.

[0179] The polyurethaneurea according to the invention is preferably present in a physiologically acceptable medium. The medium is particularly preferably water, and the polyurethaneurea is most preferably present as an aqueous dispersion. Water generally forms, along with other optionally present liquid media, such as solvents, the main constituent (>50 wt. %) of the dispersing medium, based on the total amount of the liquid dispersing medium, and may also be the sole liquid dispersing medium.

[0180] The resulting aqueous polyurethaneurea dispersions preferably have a content of volatile organic compounds (VOCs), such as volatile organic solvents, of less than 10 wt. %, more preferably less than 3 wt. %, and even more preferably less than 1 wt. %, based on the aqueous polyurethaneurea dispersion. VOCs in the context of this invention are, in particular, organic compounds with an initial boiling point of at most 250°C at a standard pressure of 101.3 kPa.

[0181] In the context of the present invention, the content of volatile organic compounds (VOC) is determined in particular by gas chromatographic analysis.

[0182] The pH of the aqueous polyurethane dispersions is typically less than 8.0, preferably less than 7.5 and particularly preferably between 5.5 and 7.5.

[0183] In order to achieve good sedimentation stability, the number-average particle size of the special polyurethaneurea dispersions is preferably less than 750 nm, particularly preferably less than 500 nm, determined by laser correlation spectroscopy after dilution with deionized water (instrument: Malvern Zetasizer 1000, Malvern Inst. Limited).

[0184] The solids content of the polyurethaneurea dispersions is preferably 10 to 70 wt.%, particularly preferably 20 to 60 wt.%, and most preferably 40 to 60 wt.%. The solids contents are determined by heating a weighed sample to 125°C until constant weight is reached. At constant weight, the solids content is calculated by reweighing the sample.

[0185] These polyurethaneurea dispersions preferably contain less than 5% by weight, particularly preferably less than 0.2% by weight, of unbound organic amines, based on the mass of the dispersions.

[0186] At a constant shear rate of 10 s -1<, the polyurethaneurea dispersion preferably has a viscosity of ≥ 1 and ≤ 10,000 mPa s, particularly preferably ≥ 10 and ≤ 5,000 mPa s, and most preferably ≥ 100 and ≤ 4,000 mPa s. The viscosity is determined as described in the methods section.

[0187] Preferably, the polyurethaneurea used is therefore dispersible in water, which in the context of this invention means that the polyurethaneurea can form a sedimentation-stable dispersion in water, in particular deionized water, at 23°C.

[0188] The polyurethaneurea according to the invention is preferably obtainable by preparing isocyanate-functional polyurethane prepolymers a) from components A), H), B) and optionally D) and / or C2), and optionally the compounds E) (step a) and then reacting their free NCO groups wholly or partially with the amino-functional chain extender component C), and also with component G) and optionally with component D) (step b)). Component H) can also be added only in step b), although this is less preferred. If component H) is not used until step b), it is preferably added before the addition of component C) and reacted with prepolymer a).

[0189] Components A) to H) are defined as above and the above-mentioned embodiments, including all preferred ranges, also apply to the manufacturing process.

[0190] The invention therefore also provides a process for preparing the polyurethaneurea according to the invention, in which isocyanate-functional polyurethane prepolymers a) are prepared from components A), H), B) and optionally D) and / or C2), and optionally the compounds E) (step a) and their free NCO groups are then reacted wholly or partially with the amino-functional chain extender component C), as well as component G) and optionally component D) (step b)). Component H) can also be added only in step b), although this is less preferred. If component H) is not used until step b), it is preferably added before the addition of component C) and reacted with prepolymer a).

[0191] Components A) to H) are also defined as above and the above-mentioned embodiments, including all preferred ranges, also apply to the manufacturing process.

[0192] In a preferred embodiment, components A) and H) are used in premixed form in step a).

[0193] The invention also relates to an adhesive, preferably a contact adhesive, comprising the polyurethaneurea according to the invention.

[0194] Furthermore, the invention relates to an object produced by bonding two or more substrates by means of the polyurethane urea according to the invention or the adhesive according to the invention.

[0195] Preferred substrates are textile fabrics, metal, glass, ceramic, concrete, natural stone, leather, natural fibers, and plastics such as PVC, polyolefins, polyurethane, or similar. Three-dimensional structures are also suitable. The substrates listed above for the contact adhesive product are particularly preferred.

[0196] An object according to the invention can be a means of transport such as a car, a motorcycle, an airplane, a train; a truck or a bicycle; an electrical article such as a mobile phone or a computer; a building; a piece of furniture; a conveyor belt, a construction machine, packaging material, tools, an office item, a piece of clothing, a shoe, a household article, a medical device; whereby the bonding can also relate to individual or multiple parts of the objects mentioned.

[0197] Furthermore, the invention relates to an aqueous dispersion containing a polyurethaneurea according to the invention.

[0198] Furthermore, the invention relates to the use of the polyurethane urea or contact adhesive according to the invention for the production of contact-adhesive substrates such as adhesive tapes for use in the home or craft, as well as for industrial use.

[0199] Furthermore, the invention relates to the use of the polyurethane urea or contact adhesive according to the invention for the production of plasters, dressings, tapes or bandages.

[0200] The present invention is illustrated by the following examples. Examples: Methods:

[0201] Unless otherwise indicated, all percentages refer to the weight and total quantity or to the total weight of the compositions.

[0202] Unless otherwise stated, all analytical measurements refer to measurements at temperatures of 23 °C.

[0203] The solids content was determined according to DIN EN ISO 3251 by heating a weighed sample to 105 °C until constant weight was reached. At constant weight, the solids content was calculated by reweighing the sample.

[0204] Unless explicitly stated otherwise, NCO values ​​were determined volumetrically according to DIN-EN ISO 11909.

[0205] The presence of free NCO groups was checked by IR spectroscopy (band at 2260 cm -1< ).

[0206] The stated viscosities were determined by rotational viscometry according to DIN 53019 at 23 °C using a rotational viscometer from Anton Paar Germany GmbH, Ostfildern, DE (1 Pa s = 1 N / m 2< *s).

[0207] The mean particle sizes (number average) of the polyurethane dispersions were determined after dilution with deionized water using laser correlation spectroscopy (instrument: Malvern Zetasizer 1000, Malver Inst. Limited).

[0208] The pH value was measured on the undiluted sample according to the method described in DIN ISO 976.

[0209] The glass transition temperature T g was determined by differential scanning calorimetry (DSC) in accordance with DIN EN 61006, method A, using a DSC instrument (Pyris Diamond DSC calorimeter from Perkin-Elmer) calibrated to determine T g with indium and lead. 10 mg of the substance to be tested is weighed into a sealable aluminum crucible, which is then sealed. Three consecutive heating runs from -100°C to +150°C at a heating rate of 20 K / min, followed by cooling at a cooling rate of 320 K / min, are carried out. The third heating curve is used to determine the values. T g is determined as the temperature at half the height of a glass transition step.

[0210] The air permeability of the substrates in the unstretched state was determined according to DIN EN ISO 9237.

[0211] The maximum tensile strength of the substrates was determined using a strip tensile test according to DIN EN ISO 13934-1.

[0212] The elongation range of the substrates was determined by determining the tensile elastic behavior of the substrates by means of repeated tensile stress between constant yield points and by determining the total elongation according to DIN 53835 Part 2. Substances and abbreviations used:

[0213] Diaminosulfonate: NH 2 -CH 2 CH 2 -NH-CH 2 CH 2 -SO 3 Na (45% in water) PolyTHF 1000 Poly(tetramethylene glycol) polyetherdiol with a number-average molecular weight of 1000 g / mol, BASF SE, Ludwigshafen, DE PolyTHF 2000 Poly(tetramethylene glycol) polyetherdiol with a number-average molecular weight of 2000 g / mol, BASF SE, Ludwigshafen, DE Water Deionized water using ion exchangers

[0214] The isocyanate components used are commercial products of Covestro Deutschland AG, Leverkusen, Germany. Other chemicals are from Sigma-Aldrich Chemie GmbH, Taufkirchen, Germany. Unless otherwise stated, the raw materials were used without further purification or pretreatment. Polyurethane urea dispersion 1 not according to the invention

[0215] 360 g of PolyTHF ®< 1000 and 1680 g of PolyTHF ®< 2000 were heated to 70°C. A mixture of 180.6 g of hexamethylene diisocyanate and 238.7 g of isophorone diisocyanate was then added and stirred at 100-115°C until the NCO content fell below the theoretical value. The finished prepolymer was dissolved in 4400 g of acetone at 50°C, and then a solution of 19.6 g of ethylenediamine, 86.3 g of diaminosulfonate, 27.9 g of diethanolamine, and 380 g of water was added. Stirring was continued for 15 minutes. Dispersal was then effected by adding 2100 g of water. The solvent was then removed by distillation under vacuum, yielding a storage-stable dispersion; the solids content was adjusted by adding water. Solids content: 52 % Particle size (LKS): 292 nm Viscosity: 440 mPa s Tg polyurethane urea: -78,7 °C Inventive polyurethaneurea dispersion 2

[0216] 75 g of PolyTHF ®< 1000 and 350 g of PolyTHF ®< 2000 were heated to 70°C. A mixture of 33.9 g of hexamethylene diisocyanate, 49.7 g of isophorone diisocyanate, and 8.7 g of Desmodur N 3300 (HDI trimer with an NCO content of approximately 21.8% according to DIN EN ISO 11 909) was then added and stirred at 100-115°C until the NCO content fell below the theoretical limit. The finished prepolymer was dissolved in 920 g of acetone at 50°C, and a solution of 3.2 g of ethylenediamine, 12.9 g of diaminosulfonate, 11.7 g of diethanolamine, and 145 g of water was then added. The stirring time was 15 minutes. Dispersal was then achieved by adding 1080 g of water. The solvent was then removed by distillation under vacuum, yielding a storage-stable dispersion. The solids content was adjusted by adding water. Solids content: 52 % Particle size (LKS): 307 nm Viscosity: 105 mPa s Tg polyurethane urea: -78,0 °C Polyurethane urea dispersion V1 (Comparison 1)

[0217] 450 g of PolyTHF ®< 1000 and 2100 g of PolyTHF ®< 2000 were heated to 70°C. A mixture of 225.8 g of hexamethylene diisocyanate and 298.4 g of isophorone diisocyanate was then added and stirred at 100-115°C until the NCO content fell below the theoretical value. The finished prepolymer was dissolved in 5460 g of acetone at 50°C, and then a solution of 29.5 g of ethylenediamine, 143.2 g of diaminosulfonate, and 610 g of water was added. Stirring was continued for 15 minutes. The mixture was then dispersed by adding 1880 g of water. The solvent was then removed by distillation under reduced pressure, yielding a storage-stable dispersion; the solids content was adjusted by adding water. Solids content: 56 % Particle size (LKS): 276 nm Viscosity: 1000 mPas Tg polyurethane urea: -79,1 °C Polyurethane dispersion V2 according to US 5,692,937 (Comparison 2)

[0218] The polyurethane dispersion described in US Pat. No. 5,692,937, Example 1 (column 4, lines 15 to 34) was reproduced. The IPDI and polyols were obtained from Covestro AG, Leverkusen, Germany, while all other chemicals were obtained from Sigma-Aldrich Chemie GmbH, Taufkirchen, Germany.

[0219] The polyurethane dispersions of the comparative examples were prepared in apparatus and under conditions comparable to those in US 5,692,937 and the examples according to the invention. Application tests: Materials used:

[0220] Ypsiflex bandage from Holthaus Ref. 12906S: Air permeability in the unstretched state: 5548 l / m2*s, elongation range: 160%, maximum tensile strength: 155.9 N; Ypsifix bandage from Holthaus Ref. 12223 Testing contact adhesion:

[0221] After applying and drying the polyurethane urea composition to a 30 cm long Ypsifix bandage (Ref. 12223) or Ypsiflex bandage (Ref. 12906S), the bandage is wrapped around a stick so that the wraps overlap. After 14 days, the product's contact adhesion to itself is tested. This is done by placing two 3 cm long pieces on top of each other, gently pressing them together with the fingers for 10 seconds at room temperature, and then visually determining the peel behavior by pulling the two pieces apart. The rating scale ranges from 1 (does not stick to each other) to 5 (sticks very strongly to each other). A rating of "3" or higher is considered sufficient. Application example A1 (not according to the invention):

[0222] 97 g of the non-inventive polyurethaneurea dispersion 1 were placed in a Speedmixer beaker with 3 g of glycerol. Bubble-free mixing to form a polyurethaneurea composition was carried out in the Speedmixer at a rotational speed of 2750 rpm for 1 minute. For the subsequent spray test, the Holthaus Ypsiflex gauze bandage (Ref. 12906S) (6 x 30 cm 2 ) (substrate) to be wetted was fixed in a rigid frame. The formulation was transferred from the Speedmixer beaker into the receiver of a spray gun (SATA Jet RP Digital). Using an air pressure of 1.5 bar, the polyurethaneurea composition was distributed in droplets onto the substrate via a nozzle (diameter 1.6 mm). The substrate was sprayed once from each side. Before drying for 10 min at 100 °C in a circulating air drying cabinet, pre-drying was carried out for 20 min at RT.After drying, the 30 cm long coated bandage was wrapped around a pin so that the wraps overlapped. The coated bandage adhered only slightly to each other when wound and did not stick together even after 14 days of storage. The contact adhesion was assessed after 14 days and is listed in Table 1. Application example A2 (comparison):

[0223] 97 g of the comparative polyurethane urea dispersion V1 was placed in a Speedmixer beaker with 3 g of glycerol. Bubble-free mixing to form a polyurethane urea composition was carried out in the Speedmixer at a speed of 2750 rpm for 1 minute. For the spray test, the Holthaus Ypsiflex gauze bandage (Ref. 12906S) (6 x 30 cm 2 ) (substrate) to be wetted was fixed in a rigid frame. The formulation was transferred from the Speedmixer beaker into the receiver of a spray gun (SATA Jet RP Digital). Using an air pressure of 1.5 bar, the polyurethane urea composition was distributed in droplets onto the substrate via a nozzle (diameter 1.6 mm). The substrate was sprayed once from each side. Before drying for 10 minutes at 100 °C in a forced-air drying cabinet, the tape was pre-dried for 20 minutes at room temperature. After drying, the 30 cm long coated bandage was wrapped around a pin so that the windings overlapped.The contact adhesion is assessed after 14 days and is listed in Table 1. Application example A3 (according to the invention):

[0224] For the spray test, the Ypsifix gauze bandage (Ref. 12223) (6 x 30 cm 2 ) (substrate) to be wetted was fixed in a rigid frame. 100 g of the untreated, inventive polyurethaneurea dispersion 2 was transferred to the receiver of a spray gun (SATA Jet RP Digital). Using an air pressure of 1.5 bar, the dispersion was distributed in droplets onto the substrate via a nozzle (diameter 1.6 mm). The substrate was sprayed once from each side. Drying took place for 60 minutes at 100°C in a circulating air drying cabinet. After drying, the 30 cm long coated bandage was wrapped around a pin so that the windings lay one on top of the other. The coated bandage adhered only slightly to one another when wound up and did not stick together even after 14 days of storage. The contact adhesion was assessed after 14 days and is listed in Table 1. Application example A4 (not according to the invention):

[0225] 180 g of the non-inventive polyurethaneurea dispersion 1 were mixed with 0.9 g of Rheolate 678 using a KPG laboratory stirrer (rotational speed: 1100 min -1 and stirring time: 5 min) to form a polyurethaneurea composition. The Ypsiflex bandage (Ref. 12906S) (6 x 30 cm 2 ) (substrate) to be wetted was fixed in a tenter frame of a Mathis oven. The prepared polyurethaneurea composition was applied to the upper part of the fixed textile and then evenly distributed by coating with a doctor blade. The doctor blade gap was 100 µm. Drying took place in a Mathis oven at 120 °C for 2 min. The contact adhesion of the unrolled bandage was tested after 14 days and is listed in Table 1. Application example A5 (comparison):

[0226] For the spray test, the Ypsiflex gauze bandage (Ref. 12906S) (6 x 30 cm 2 ) (substrate) to be wetted was fixed in a rigid frame. 100 g of the untreated comparison polyurethane urea dispersion V2 was transferred to the receiver of a spray gun (SATA Jet RP Digital). Using an air pressure of 1.5 bar, the dispersion was distributed in droplets onto the substrate via a nozzle (diameter 1.6 mm). The substrate was sprayed once from each side. Before drying for 10 minutes at 100 °C in a circulating air drying cabinet, pre-drying took place for 20 minutes at room temperature. After drying, the 30 cm long, coated bandage was wrapped around a pin so that the wraps lay on top of each other. The contact adhesion was assessed after 14 days and is listed in Table 1. Table 1: Test of contact adhesion after 14 days: After 14 days Example A1 (not according to the invention) Example A2 (comparison) Example A3 Example A4 (not according to the invention) Example A5 (comparison) Evaluation 3 1 4 3 1-2 Testing the discoloration:

[0227] The color values ​​(L, a, and b according to the CIELab system) were determined using films with a layer thickness of 100 µm, which were produced on 20 cm x 10 cm and 3 mm thick glass plates from Glas & Fenster Engelbrecht GmbH, Leichlingen (Rhineland), Germany (application with a box-type doctor blade with a gap width of 200 µm and subsequent drying). The layer thickness was determined using a Heidehain (MT25P) pneumatic sensor and a display connected to the layer thickness output. A thickener was added to all formulations to improve film formation (0.5 wt. % to 100 wt. % dispersion).

[0228] The color measurement was performed in transmission using a Konica Minolta CM5 device. The color calculation was performed according to DIN 11664-4, and the measurement geometry was defined according to DIN 5033-7 with the parameters d / 8, D65, and SCi. The b-value describes the yellowness of a film. The measurement results are listed in Table 2. The measurement was performed approximately 10 days after the films were manufactured. The film thickness deviation was a maximum of 1%, based on the thickest part of the film.

[0229] It can be seen that the b values ​​of the inventive samples exhibit significantly lower discoloration than the comparison samples. In particular, the aliphatic isocyanates, unlike aromatic isocyanates, are not light-sensitive. While aromatic isocyanates exhibit a yellow discoloration upon exposure to sunlight, aliphatic isocyanates exhibit no discoloration at all due to UV radiation such as sunlight.

[0230] Formulations used for color measurement: Application example A6 (not according to the invention), corresponds to A1 and A4:

[0231] 100 g of the non-inventive polyurethaneurea dispersion 1 were placed in a speed mixer beaker with 3 g of glycerol and 0.5 g of Rheolate 210. Bubble-free mixing to form a polyurethaneurea composition was carried out in the speed mixer at a speed of 2750 rpm for 1 minute. After application by doctor blade and prior to drying for 10 minutes at 50 °C and 3 minutes at 120 °C in a forced-air drying cabinet, pre-drying was carried out for 20 minutes at RT. Application example A7 (comparison), corresponds to A2:

[0232] 100 g of the comparative polyurethaneurea dispersion V1 were placed in a speed mixer beaker with 3 g of glycerol and 0.5 g of Rheolate 210. Bubble-free mixing to form a polyurethaneurea composition was carried out in the speed mixer at a speed of 2750 rpm for 1 minute. After application by doctor blade and prior to drying for 10 minutes at 50 °C and 3 minutes at 120 °C in a forced-air drying cabinet, pre-drying was carried out for 20 minutes at room temperature. Application example A8 (according to the invention), corresponds to A3:

[0233] 100 g of the inventive polyurethaneurea dispersion 2 were placed in a speed mixer beaker with 0.5 g of Rheolate 210. Bubble-free mixing to form a polyurethaneurea composition was carried out in the speed mixer at a speed of 2750 rpm for 1 minute. After application by doctor blade and prior to drying for 10 minutes at 50 °C and 3 minutes at 120 °C in a forced-air drying cabinet, pre-drying was carried out for 20 minutes at room temperature. Application example A9 (comparison), corresponds to A5:

[0234] 100 g of the comparative polyurethaneurea dispersion V2 was placed in a speed mixer beaker with 0.5 g of Rheolate 210. Bubble-free mixing to form a polyurethaneurea composition was carried out in the speed mixer at a speed of 2750 rpm for 1 minute. After application by doctor blade and prior to drying for 10 minutes at 50 °C and 3 minutes at 120 °C in a forced-air drying cabinet, pre-drying was carried out for 20 minutes at room temperature. Table 2: Measurement of color values: Example A6 (not according to the invention) Example A7 (comparison) Example A8 Example A9 (comparison) Layer thickness (µm) 73 98 87 83 L-value 96,6 96,6 96,6 96,4 a-value -0,5 -0,5 -0,5 -0,6 b-value 0,3 0,2 0,3 1,0

Claims

1. Contact-adhesive product comprising a substrate and a polyurethaneurea obtainable by reacting at least A) an aliphatic polyisocyanate component having an average isocyanate functionality of ≥ 1.8 and ≤ 2.6, B) a polymeric polyetherpolyol component which contains or consists of a mixture of poly(tetramethylene glycol) polyetherpolyols, where the poly(tetramethylene glycol) polyetherpolyols differ in their number-average molecular weights, C) an amino-functional chain extender component having at least 2 isocyanate-reactive amino groups, containing at least one amino-functional compound C1) that has no ionic or ionogenic groups and an amino-functional compound C2) that has ionic or ionogenic groups, D) optionally further hydrophilizing components other than C2), E) optionally hydroxy-functional compounds having a molecular weight of 62 to 399 mol / g, F) optionally at least one further polymeric polyol other than B), G) a compound having exactly one isocyanate-reactive group or a compound having more than one isocyanate-reactive group, where only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the reaction conditions chosen, and H) an aliphatic polyisocyanate component having an average isocyanate functionality of > 2.6 and ≤ 4, where the molar ratio of component G) to component H) is 5:1 to 1:5 and where components B) and F) together contain ≤ 30% by weight of component F), based on the total mass of components B) and F).

2. Product according to Claim 1, characterized in that component A) is isophorone diisocyanate and / or hexamethylene diisocyanate.

3. Product according to Claim 1 or 2, characterized in that component D) comprises nonionically hydrophilizing components.

4. Product according to any of Claims 1 to 3, characterized in that the polyurethaneurea is obtainable by preparing isocyanate-functional polyurethane prepolymers a) from components A), B) and optionally D) and / or C2), and optionally compounds E) and / or H), and the free NCO groups thereof are then wholly or partly reacted with the amino-functional chain extender component C), and also component G) and optionally components D) and H).

5. Product according to any of Claims 1 to 4, characterized in that the polyurethaneurea is amorphous and has a Tg ≤ -25°C, determined by means of dynamic differential calorimetry in accordance with DIN EN 61006, Method A.

6. Product according to any of Claims 1 to 5, characterized in that the substrate has a maximum tensile force of 100 to 500 N, determined to DIN EN ISO 13934-1.

7. Product according to any of Claims 1 to 6, characterized in that the product is a plaster, a dressing, a tape or a bandage or at least a constituent of these end products.

8. Process for producing a contact-adhesive product according to any of Claims 1 to 7, comprising the steps of I) applying the polyurethaneurea to the substrate in the form of an aqueous polyurethaneurea dispersion and II) thermally drying the treated substrate at temperatures ≥ 20°C and ≤ 200°C.

9. Polyurethaneurea obtainable by reacting at least A) an aliphatic polyisocyanate component having an average isocyanate functionality of ≥ 1.8 and ≤ 2.6, B) a polymeric polyetherpolyol component which contains or consists of a mixture of poly(tetramethylene glycol) polyetherpolyols, where the poly(tetramethylene glycol) polyetherpolyols differ in their number-average molecular weights, C) an amino-functional chain extender component having at least 2 isocyanate-reactive amino groups, containing at least one amino-functional compound C1) that has no ionic or ionogenic groups and an amino-functional compound C2) that has ionic or ionogenic groups, D) optionally further hydrophilizing components other than C2), E) optionally hydroxy-functional compounds having a molecular weight of 62 to 399 mol / g, F) optionally further polymeric polyols other than B), G) a compound having exactly one isocyanate-reactive group or a compound having more than one isocyanate-reactive group, where only one of the isocyanate-reactive groups reacts with the isocyanate groups present in the reaction mixture under the reaction conditions chosen, and H) an aliphatic polyisocyanate component having an average isocyanate functionality of > 2.6 and ≤ 4, where components B) and F) together contain ≤ 30% by weight of component F), based on the total mass of components B) and F), and components G) and H) are present in a molar ratio of 5:1 to 1:5.

10. Adhesive comprising a polyurethaneurea according to Claim 9.

11. Object produced by bonding two or more substrates by means of a polyurethaneurea according to Claim 9 or an adhesive according to Claim 10.

12. Aqueous dispersion comprising a polyurethaneurea according to Claim 9.