One-component system comprising blocked polyurethane prepolymer

Abstract

To provide a one-component system, a method for producing the same, use of the same and a method for using the same for producing artificial leather and (artificial) leather coating.SOLUTION: A one-component system comprises: a) at least one polyurethane prepolymer based on at least one diisocyanate and / or polyisocyanate and at least one diol and / or polyol, wherein the at least one diol or polyol is a polyalkylene glycol having a number average molecular weight of 900 to 2,150 g / mol, and all unreacted isocyanate groups are blocked with at least one malonate ester; and b) at least one diamine and / or polyamine.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a one-component system that can be used in the production of artificial leather and (artificial) leather coatings, and a method for producing the same. The present invention further relates to the use of the one-component system for producing artificial leather or (artificial) leather coatings and a method for producing artificial leather or (artificial) leather coatings.

Background Art

[0002] Artificial leather is a fibrous and other flexible sheet-like product made using plastic, and may have a coating layer having properties and / or surface structure (e.g., embossing) partially similar to leather corresponding to the intended use. The term "artificial leather" is in this case understood to be, in particular, a leather-like material comprising at least one support layer (e.g., made of paper, cotton or plastic, in particular polyester) and at least one planar-mounted (e.g., coated) plastic coating.

[0003] In contrast, an "(artificial) leather coating" is a plastic coating that can be applied to either natural leather or artificial leather in order to achieve special properties typical of artificial leather.

[0004] Recently, plastics based on polyurethane prepolymers crosslinked with at least bifunctional alcohols and / or amines have been found to result in particularly advantageous properties of the resulting artificial leather and (artificial) leather coatings. Polyurethane prepolymers are to be understood in this case as isocyanate-terminated reaction products of oligomers or polymers having at least one urethane bond, which can be produced from a deficient amount of polyol and an excess amount of diisocyanate or polyisocyanate. Pure polyurethane prepolymers produced from diisocyanate or polyisocyanate and a polyol component may already react with the above crosslinking agents at room temperature, so these must be stored in separate containers. Therefore, the technology belonging to this is called two-component technology.

[0005] Japanese Patent Publication No. 2014-105250 (JP 2014-105250 A) discloses a urethane prepolymer composition containing a hydroxyl-terminated urethane prepolymer, which is produced from 20-80% by mass of a hydroxyl-terminated urethane prepolymer and 20-80% by mass of an oligomer without urethane groups. This composition is processed into synthetic imitation leather as a component of a two-component system having a corresponding crosslinking agent.

[0006] Chinese Patent Application Publication No. 102758359 (CN 102758359 A) discloses a method for manufacturing a two-component polyurethane foam coating, in which, first, a lower foam layer is manufactured from polyurethane component A (polyol or polyamine) and polyurethane component B (diisocyanate-based isocyanate monomer or a prepolymer of isocyanate and polyol), and subsequently, the upper layer is coated with an aqueous polyurethane composition containing aqueous polyurethane and a crosslinking agent (aliphatic epoxy resin or polyisocyanate). This polyurethane foam coating can be used as synthetic leather.

[0007] Japanese Patent Publication No. 2006-316127 (JP 2006-316127 A) discloses a solvent-free curable urethane resin composition containing a compound having an active hydrogen atom and a polyisocyanate, wherein the polyisocyanate is an adduct of glycol and diisocyanate. Synthetic leather can be manufactured using this composition.

[0008] European Patent Application Publication No. 3514189 (EP 3 514 189 A1) discloses a two-component system suitable for the manufacture of artificial leather. This polyol component is based on the reaction product of diisocyanates and isocyanurates with the polyol component.

[0009] Two-component systems have the disadvantage of reacting rapidly, so both components must be stored separately. Furthermore, they may partially cure in an undesirable manner in the apparatus. For this reason, one-component systems have been developed in which the isocyanate groups of the polyurethane prepolymer are chemically and reversibly blocked, thus avoiding reactions at room temperature when the crosslinking agent is added. Conventionally, the isocyanate groups are blocked with oximes or lactams.

[0010] For example, Japanese Patent Publication No. 2006-070059 (JP 2006-070059 A) discloses a polyurethane prepolymer made from a polycarbonate diol and an organic diisocyanate, suitable for use in a one-component system, wherein the isocyanate group is subsequently blocked. Preferably, the prepolymer was blocked with a ketoxime or lactam.

[0011] However, a drawback of blocking with ketoximes and lactams is that, in particular, toxic by-products are released during deblocking.

[0012] To solve this problem, conventional techniques teach the alternative of blocking the prepolymer with a malonate.

[0013] German Patent Application Publication No. 19622136 (DE 196 22 136 A1) discloses a method for blocking an isocyanate-polyol prepolymer with malonate.

[0014] German Patent Application Publication No. 112005001991 (DE 11 2005 001 991 T5) discloses a prepolymer based on TDI and a diol, which was blocked with diethyl malonate.

[0015] U.S. Patent No. 4,240,943 A discloses a urethane prepolymer based on hexamethylene diisocyanate and a polyester diol, which was subsequently blocked with diethyl malonate.

[0016] International Publication No. 2014 / 039306 (WO 2014 / 039306 A1) discloses the production of a diethyl malonate-blocked H12MDI-polyTHF prepolymer.

[0017] European Patent Application Publication No. 3712188 (EP 3 712 188 A1) discloses a polyisocyanate composition comprising at least one diisocyanate and a polyol having a number-average molecular weight of 400 to 5000 and an average number of hydroxyl groups of 3 to 8, wherein the diisocyanate may be reacted with a blocking agent, which may be a malonate.

[0018] U.S. Patent No. 5,863,983 discloses a method for reacting a polyol (in particular a sulfonate-blocked polyol) with an isocyanate and subsequently blocking it with a malonate.

[0019] The prior art further teaches the reaction of a malonate-blocked prepolymer with a diol or polyol.

[0020] U.S. Patent No. 4,518,522 A discloses, for example, prepolymers produced from polyalkylene glycols having different number-average molecular weights and different diisocyanates.

[0021] West German Patent Application Publication No. 2550156 (DE 25 50 156 A1) discloses a blocked polyisocyanate mixture that can be produced from a polyhydroxyl compound having a molecular weight of 62 to about 300 g / mol and an isocyanate, which is subsequently blocked with, for example, diethyl malonate. This mixture is used in baking lacquers, in which it is reacted with a compound having at least two hydrogen atoms reactive to the isocyanate group and a molecular weight of about 400 to about 50,000 g / mol.

[0022] European Patent Application Publication No. 3689936 (EP 3 689 936 A1) discloses a coating composition which may have a blocked polyisocyanate and a polyvalent hydroxy compound. The blocked polyisocyanate may have urethane units formed by reaction with a hydrophilic compound. The hydrophilic compound may be an ethylene oxide-based polyether polyol, preferably having 30 or fewer ethylene oxide units.

[0023] European Patent Application Publication No. 53766 (EP 53 766 A1) discloses a composition comprising a prepolymer of an isocyanate and a polyol, wherein the isocyanate is blocked with a malonate and cured with the polyol. A coating is produced using the system described in the specification. Curing with an amine is indicated as unfavorable in the specification.

[0024] The prior art further describes curing malonate-blocked prepolymers with amines. Curing with amines has the advantage of being more rapid and / or catalyst-free. Furthermore, conventional diols and polyols suitable for curing have the disadvantage of being hygroscopic.

[0025] European Patent Application Publication No. 3348593 (EP 3 348 593 A1) discloses a blocked polyisocyanate of a diisocyanate and a malonic acid diester. This polyisocyanate can be produced by reacting a diisocyanate with a di-hexavalent alcohol (e.g., trimethylolpropane). The specification discloses the use of this blocked polyisocyanate in a one-component composition which may contain a polyamine.

[0026] U.S. Patent No. 5,071,937 A discloses coating compositions having malonate-blocked isocyanate prepolymers of isocyanates and polyols having molecular weights of 400 to 10,000 g / mol, as well as sterically hindered aromatic polyamines. Furthermore, the use of these compositions together with the polyols used in their manufacture is disclosed for producing coating compositions that can be used for a variety of purposes. However, the use of aromatic amines is unfavorable due to potential health risks and the negative properties of the resulting coatings.

[0027] The prior art further discloses curing a malonate-blocked prepolymer based on a polyether and isocyanate with an amine.

[0028] U.S. Patent No. 4,439,593 (US 4,439,593 A) and U.S. Patent No. 4,677,180 (US 4,677,180 A) disclose coating compositions having prepolymers blocked with malonate from isocyanates and polyols. The polyol is a compound having a number average molecular weight of 100 to 10,000 g / mol, preferably 400 to 8,000 g / mol or 800 to 8,000 g / mol. Preferably, the compound is a polyether. The coating composition may further contain diamines and can be used for various purposes. Amines that can be used include, inter alia, isophoronediamine and 4,4'-diaminodicyclohexylmethane.

[0029] European Patent Application Publication No. 0,034,272 (EP 0 034 272) discloses a method for manufacturing a sheet product having a suede-like surface, in which a coating paste containing a blocked NCO prepolymer and a polyamine is used. The NCO prepolymer has a molecular weight of 500 to 10,000, preferably 1,000 to 6,000 g / mol and may be produced from a compound having a hydroxyl group and various diisocyanates. Preferred is a polypropylene oxide polyether having an average molecular weight of 1,000 to 6,000 g / mol. This blocking can be carried out, inter alia, with malonic esters, but preferably with butanone oxime.

[0030] International Publication No. 2017 / 107064 (WO 2017 / 107064 A1) discloses a composition comprising at least one blocked isocyanate-terminated prepolymer (prepared from a polyol component and an isocyanate component) and at least one polyamine, which is particularly suitable for the production or coating of leather articles. The polyol component preferably has a number average molecular weight of 2000 to 8000 g / mol, more preferably 2500 to 7000 g / mol, and most preferably 3000 to 6500 g / mol. This component may be a polyether polyol. The isocyanate component may be an aliphatic polyisocyanate or an aromatic polyisocyanate. The prepolymer may be blocked, inter alia, with malonate.

[0031] However, with the one-component (1K) compositions described in the prior art, it is not possible to produce artificial leather and (artificial) leather coatings having sufficiently good properties. In particular, with the 1K compositions known hitherto, it has not been possible to achieve sufficiently good tensile strength and elongation values in combination with good modulus of elasticity values. Desirable are tensile strengths of 17 to 23 N / mm , , , , , , , , elongation values of 600 to 900% and modulus of elasticity values of 2 to 4.5 MPa at 100%, 4 to 7 MPa at 200% and 5.5 to 10 MPa at 300% (all values measured according to DIN EN ISO 527).

Prior Art Documents

Patent Documents

[0032]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

[0033] Accordingly, the object of the present invention is to avoid the drawbacks of the prior art. In particular, the object of the present invention is to provide a one-component composition that does not dissociate toxic by-products during curing and that can produce artificial leather and (artificial) leather coatings having good properties, especially with respect to the above parameters, such as tensile strength, elongation and modulus of elasticity. [Means for solving the problem]

[0034] This problem is solved by a one-component system according to the present invention, which includes the following: a) At least one polyurethane prepolymer based on at least one diisocyanate and / or polyisocyanate and at least one diol and / or polyol, wherein at least one diol or polyol is a polyalkylene glycol having a number average molecular weight of 900 to 2150 g / mol, and all unreacted isocyanate groups of the polyurethane prepolymer are blocked with at least one malonic acid ester, and b) at least one diamine and / or polyamine.

[0035] a) Polyurethane prepolymer A polyurethane prepolymer "based on" at least one diisocyanate and / or polyisocyanate and at least one diol and / or polyol should be understood as an isocyanate-terminated reaction product of an oligomer or polymer having at least two urethane bonds (formed by the reaction of one hydroxyl group of the at least one diol and / or polyol with one isocyanate group of the diisocyanate or polyisocyanate), which can be produced from a deficiency of at least one diol and / or at least one polyol and an excess of at least one diisocyanate and / or at least one polyisocyanate, wherein the unreacted terminal isocyanate groups remain blocked. The blocking of the (one or more) unreacted isocyanate groups with the at least one malonic acid ester is achieved by the bonding of the α-CH acidic carbon atom of the malonic acid ester to the electrophilic carbon atom of the (one or more) isocyanate groups.

[0036] Diisocyanates / Polyisocyanates In principle, the prepolymer is based on one or more diisocyanates and / or polyisocyanates. However, particularly good properties arise when the prepolymer is based on one diisocyanate or polyisocyanate. In this case, the polyisocyanate should be understood as a compound having at least three isocyanate groups.

[0037] In principle, the prepolymer may be based on at least one diisocyanate and / or polyisocyanate. However, particularly good properties are achieved with at least one diisocyanate or at least one polyisocyanate. More preferably, the prepolymer is based on one diisocyanate or one polyisocyanate. Even more preferably, the prepolymer is based on one diisocyanate.

[0038] Preferably, the prepolymer is based on at least one (cyclic)aliphatic diisocyanate, i.e., at least one diisocyanate having an isocyanate group bonded to a cyclic group and / or an aliphatic group. Even more preferably, the prepolymer is based on one (cyclic)aliphatic diisocyanate. Systems based on aromatic compounds (i.e., non-(cyclic)aliphatic compounds) lead to unfavorable properties, particularly with respect to yellowing.

[0039] More preferably, the at least one diisocyanate is HDI (hexamethylene diisocyanate), TMDI (a mixture of 2,2,4- and 2,4,4-trimethylhexamethylene diisocyanate), H12MDI (4,4′-methylene-bis-(cyclohexyl isocyanate)), IPDI (isophorone diisocyanate), TMXDI (o-tetramethylxylylene diisocyanate, m-tetramethylxylylene diisocyanate, p The diisocyanates are selected from (-tetramethylxylylene diisocyanate or a mixture thereof), XDI (o-xylylene diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate or a mixture thereof), MDI (diphenylmethane-2,2′-diisocyanate, diphenylmethane-2,4′-diisocyanate, diphenylmethane-4,4′-diisocyanate or a mixture thereof), and TDI (toluene-2,4-diisocyanate). More preferably, at least one of the diisocyanates is selected from HDI, TMDI, H12MDI, and IPDI. Particularly good results are obtained when the one diisocyanate is selected from HDI, TMDI, H12MDI, IPDI, TMXDI, XDI, MDI, and TDI. Extremely good results are obtained when the aforementioned diisocyanate is selected from HDI, TMDI, H12MDI, and IPDI (isophorone diisocyanate). The best results are obtained when the diisocyanate is IPDI.

[0040] The prepolymer may be based on at least one polyisocyanate. Preferably, the prepolymer is further based on at least one, preferably one, diisocyanate and at least one, more preferably one, polyisocyanate. Particularly preferably, the polyisocyanate is a polyisocyanate derived from IPDI, HDI, H12MDI, or TDI. Particularly preferred polyisocyanates are the corresponding isocyanurates, most preferably isocyanurates of IPDI and HDI.

[0041] The prepolymer preferably has a polyisocyanate base of 0 to 40% by weight, more preferably 0 to 30% by weight, and even more preferably 0 to 20% by weight, based on the total mass of diisocyanate and polyisocyanate.

[0042] Diol / Polyol In principle, the prepolymer is based on one diol or two or more diols and / or one polyol or two or more polyols. However, particularly good properties arise when the prepolymer is based on one diol or polyol or two diols or polyols in total. The polyol should be understood in this case as a compound having at least three hydroxyl groups. Particularly good properties are achieved with at least one diol. More preferably, the prepolymer is based on one or two, more preferably two, diols. Even more preferably, the prepolymer is based on 80-100% by weight of a first diol and 0-20% by weight of a second diol, where the weight is based on the total mass of the diols. Most preferably, the prepolymer is based on two diols. More preferably, the prepolymer is based on a first diol in an amount of 80 to 99.9% by weight, more preferably 80 to 95% by weight, and on a second diol in an amount of 0.1 to 20% by weight, more preferably 5 to 20% by weight, where the weight is based on the total mass of the diol.

[0043] According to the present invention, at least one diol and / or polyol is a polyalkylene glycol having a number-average molecular weight of 900 to 2150 g / mol, where the number-average molecular weight is determined using GPC and THF as the eluent, in accordance with DIN EN ISO 13885-1. When only one diol or polyol is used, the prepolymer is based exclusively on a polyalkylene glycol having a number-average molecular weight of 900 to 2150 g / mol as the diol / polyol.

[0044] If more than one type of diol or polyol is used, the proportion of the polyalkylene glycol is preferably at least 50% by weight, more preferably at least 60% by weight, and even more preferably at least 70% by weight, based on the total mass of other diols and / or polyols present during the production of the polyurethane prepolymer. Preferably, the polyalkylene glycol is the first diol described above.

[0045] Particularly favorable results are achieved when the polyalkylene glycol is polytetramethylene ether glycol (PolyTHF). More preferably, the first diol is polytetramethylene ether glycol.

[0046] The best results are achieved when the polytetramethylene ether glycol has a number-average molecular weight of 950 to 2100 g / mol. Corresponding preferred commercial products are polyTHF1000, polyTHF1800, and polyTHF2000 (BASF). Most preferably, its number-average molecular weight is 950 to 1200 g / mol. The corresponding most preferably commercial product is polyTHF1000 (BASF).

[0047] If the prepolymer is based on more than one diol / polyol, the production of the prepolymer may also use at least one further diol or polyol, preferably one second diol or polyol, in addition to the polyalkylene glycol. Preferably, the prepolymer is based on the polyalkylene glycol and one further diol or polyol. Even more preferably, the prepolymer is based on the polyalkylene glycol and one second diol.

[0048] To achieve good properties, the further or second diol is, - Hydroxyl-terminated polyester diols, particularly adipate diols, succinate diols, and phthalate diols, having a number-average molecular weight of preferably 500 to 3000 g / mol, and especially preferably 1000 to 2000 g / mol. - Hydroxyl-terminated polycarbonate diols, preferably having a number-average molecular weight of 500-3000 g / mol, more preferably 1000-2000 g / mol. - Hydroxyl-terminated polycaprolactone diols, preferably having a number-average molecular weight of 500-3000 g / mol, more preferably 1000-2000 g / mol, and - Hydrocarbon diols having 2 to 10 carbon atoms It is selected from the group consisting of the following.

[0049] Most preferably, the further or second diol is a hydrocarbon diol having 2 to 10 carbon atoms. More preferably, the prepolymer is based on a hydrocarbon diol selected from ethylene glycol, n-propylene glycol, isopropane glycol, 2-methyl-1,3-propanediol, n-butylene glycol and n-pentyl glycol, n-hexanediol, diethylene glycol, 1,4-cyclohexanedimethanol, tripropylene glycol and 1,10-decanediol. Even more preferably, the prepolymer is based on a hydrocarbon diol selected from ethylene glycol, n-propylene glycol, isopropane glycol, 2-methyl-1,3-propanediol, n-butylene glycol and n-pentyl glycol and n-hexanediol. Particularly preferably, the prepolymer is based on n-butylene glycol.

[0050] Particularly preferred, the prepolymer is based on a polytetramethylene ether glycol having a number-average molecular weight of 950 to 1200 g / mol and n-butylene glycol.

[0051] Malonic acid ester Since a diol or polyol is used insufficient amounts during the production of the polyurethane prepolymer, the resulting intermediate product has unreacted isocyanate groups. These isocyanate groups are blocked with at least one malonic acid ester during the production of the polyurethane prepolymer. In this case, previously free isocyanate residues may be blocked with monoalkylmalonates and dialkylmalonates. Preferably, they are blocked with one malonic acid ester. Even more preferably, they are blocked with one malonic acid ester selected from dimethylmalonate, diethylmalonate, diisopropylmalonate and monoethylmalonate. Most particularly preferably, they are blocked with diethylmalonate.

[0052] Method for producing the prepolymer The following describes the production of a polyurethane prepolymer contained in the aforementioned one-component system. In this production, a) at least one diol and / or polyol is reacted with an excess amount of at least one diisocyanate and / or polyisocyanate, and subsequently, b) unreacted isocyanate groups are blocked with at least one malonic acid ester.

[0053] In principle, one or more diisocyanates and / or polyisocyanates can be used. However, particularly good properties arise when only one diisocyanate or polyisocyanate is used. In this case, the polyisocyanate should be understood to be a compound having at least three isocyanate groups.

[0054] In principle, at least one diisocyanate and / or polyisocyanate can be used. However, particularly good properties are achieved with at least one diisocyanate or at least one polyisocyanate. More preferably, one diisocyanate or polyisocyanate is used. Even more preferably, one diisocyanate is used.

[0055] Most preferably, at least one (cyclic) aliphatic diisocyanate, i.e., at least one diisocyanate having an isocyanate group bonded to a cyclic group and / or an aliphatic group, is used. Even more preferably, one (cyclic) aliphatic diisocyanate is used. Polymers based on aromatic compounds have unfavorable properties, particularly with respect to yellowing during subsequent use.

[0056] More preferably, the at least one diisocyanate is HDI (hexamethylene diisocyanate), TMDI (a mixture of 2,2,4- and 2,4,4-trimethylhexamethylene diisocyanate), H12MDI (4,4′-methylene-bis-(cyclohexyl isocyanate)), IPDI (isophorone diisocyanate), TMXDI (o-tetramethylxylylene diisocyanate, m-tetramethylxylylene diisocyanate, p The diisocyanates are selected from (-tetramethylxylylene diisocyanate or a mixture thereof), XDI (o-xylylene diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate or a mixture thereof), MDI (diphenylmethane-2,2′-diisocyanate, diphenylmethane-2,4′-diisocyanate, diphenylmethane-4,4′-diisocyanate or a mixture thereof), and TDI (toluene-2,4-diisocyanate). More preferably, at least one of the diisocyanates is selected from HDI, TMDI, H12MDI, and IPDI. Particularly good results are obtained when the one diisocyanate is selected from HDI, TMDI, H12MDI, IPDI, TMXDI, XDI, MDI, and TDI. Extremely good results are obtained when the one diisocyanate is selected from HDI, TMDI, HMDI, and IPDI. The best results are obtained when the diisocyanate is IPDI.

[0057] In this method, at least one polyisocyanate can also be used. Preferably, in the method according to the present invention, at least one, preferably one, diisocyanate and at least one, more preferably one, polyisocyanate are used. Particularly preferably, polyisocyanates derived from IPDI, HDI, H12MDI, or TDI are used. Particularly preferred polyisocyanates are the corresponding isocyanurates, most preferably isocyanurates of IPDI and HDI.

[0058] In this method, a polyisocyanate is used in an amount of 0 to 40% by weight, more preferably 0 to 30% by weight, and even more preferably 0 to 20% by weight, based on the total mass of diisocyanate and polyisocyanate.

[0059] This method uses at least one diisocyanate and / or polyisocyanate, in addition to at least one diol and / or one polyol. However, particularly good properties are obtained when one diol or polyol, two diols or polyols in total, or a mixture of one diol and one polyol are used. The polyol should be understood in this case to be a compound having at least three hydroxyl groups. Particularly good properties are achieved with at least one diol. More preferably, one to two diols are used. Very preferably, two diols are used. Even more preferably, 80 to 100% by weight of a first diol and 0 to 20% by weight of a second diol are used, where the weight is based on the total mass of the diols. Very preferably, the prepolymer is based on two diols. More preferably, 80 to 99.9% by weight, and even more preferably 80 to 95% by weight of a first diol and 0.1 to 20% by weight, and even more preferably 5 to 20% by weight of a second diol are used, where the weight is based on the total mass of the diol.

[0060] At least one diol and / or polyol is a polyalkylene glycol having a number-average molecular weight of 900 to 2150 g / mol, where the number-average molecular weight is determined according to DIN EN ISO 13885-1 using GPC and THF as the eluent.

[0061] If more than one type of diol or polyol is used, the proportion of the polyalkylene glycol is preferably at least 50% by weight, more preferably at least 60% by weight, and even more preferably at least 70% by weight, based on the total mass of the other diols and / or polyols present during the production of the polyurethane prepolymer.

[0062] Particularly favorable results are achieved when the polyalkylene glycol is polytetramethylene ether glycol (PolyTHF). More preferably, it is polytetramethylene ether glycol.

[0063] The best results are achieved when the polytetramethylene ether glycol has a number-average molecular weight of 950 to 2100 g / mol. Corresponding preferred commercial products are polyTHF1000, polyTHF1800, and polyTHF2000 (BASF). Most preferably, its number-average molecular weight is 950 to 1200 g / mol. The corresponding most preferably commercial product is polyTHF1000 (BASF).

[0064] In the production of prepolymers based on more than one diol / polyol, not only the polyalkylene glycol but also at least one further or second diol or polyol, preferably one further or second diol, is used.

[0065] To achieve good properties of the resulting prepolymer, the further or second diol is used. - Hydroxyl-terminated polyester diols, particularly adipate diols, succinate diols, and phthalate diols, having a number-average molecular weight of preferably 500 to 3000 g / mol, and especially preferably 1000 to 2000 g / mol. - Hydroxyl-terminated polycarbonate diols, preferably having a number-average molecular weight of 500-3000 g / mol, more preferably 1000-2000 g / mol. - Hydroxyl-terminated polycaprolactone diols, preferably having a number-average molecular weight of 500-3000 g / mol, more preferably 1000-2000 g / mol, and - Hydrocarbon diols having 2 to 10 carbon atoms It is selected from the group consisting of the following.

[0066] Particularly preferably, in this method, a hydrocarbon diol having 2 to 10 carbon atoms is used as a further or second diol.

[0067] More preferably, hydrocarbon diols selected from ethylene glycol, n-propylene glycol, isopropane glycol, 2-methyl-1,3-propanediol, n-butylene glycol and n-pentyl glycol, n-hexanediol, diethylene glycol, 1,4-cyclohexanedimethanol, tripropylene glycol and 1,10-decanediol are used. Even more preferably, hydrocarbon diols selected from ethylene glycol, n-propylene glycol, isopropane glycol, 2-methyl-1,3-propanediol, n-butylene glycol and n-pentyl glycol and n-hexanediol are used. Particularly preferably, n-butylene glycol is used.

[0068] In particular, two diols, specifically polytetramethylene ether glycol and n-butylene glycol having a number-average molecular weight of 800 to 1200 g / mol, are used in this method.

[0069] Reaction step a) can preferably be carried out in the absence of a solvent and at a temperature of 40-80°C, preferably 50-70°C. More preferably, reaction step a) is carried out in the presence of a catalyst, as this allows for faster reaction times and lower viscosity to be achieved. Preferred catalysts may be selected from the group consisting of optionally alkyl-substituted tin salts, zinc salts, and bismuth salts of organic acids. Particularly preferred salts are optionally alkyl-substituted acetates, laurates, and stearates of tin, zinc, and bismuth. Particularly preferably, reaction step a) of the method according to the present invention is carried out using dibutyltin dilaurate or zinc octoate.

[0070] In the production of the polyurethane prepolymer, diisocyanate or polyisocyanate is used in excess. Accordingly, the resulting intermediate product has unreacted isocyanate groups. These isocyanate groups are then blocked with at least one malonic acid ester in reaction step b). At this time, previously free isocyanate residues may be blocked with monoalkylmalonates and dialkylmalonates. Preferably, they are blocked with one malonic acid ester. More preferably, they are blocked with one malonic acid ester selected from dimethylmalonate, diethylmalonate, diisopropylmalonate and monoethylmalonate. Most preferably, they are blocked with diethylmalonate.

[0071] Reaction step b) can preferably be carried out in the absence of a solvent and at a temperature of 60 to 100°C, preferably 70 to 90°C. More preferably, reaction step b) is carried out in the presence of a catalyst. Preferred catalysts may be selected from the group consisting of optionally alkyl-substituted tin salts, zinc salts, and bismuth salts of organic acids. Particularly preferred salts are optionally alkyl-substituted acetates, laurates, stearates, octoates, neodecanoates, acetacetates, oxalates, adipates, and glucons of tin, zinc, and bismuth. Particularly preferably, reaction step a) of the method according to the present invention is carried out using dibutyltin dilaurate or zinc octoate.

[0072] The catalysts used in steps a) and b) may be the same or different. Preferably, the same catalyst is used in steps a) and b).

[0073] The amount of catalyst is preferably 0.1 to 10% by weight, and more preferably 0.1 to 7% by weight, based on the total mass of all components.

[0074] Most preferably, the reaction in step a) is carried out at a temperature of 50-70°C within 1 hour. Most preferably, the reaction in step b) is carried out so that the malonic acid ester is added at 70-90°C over a time window of up to 1 hour. A typical reaction time is 5-10 hours.

[0075] Particularly preferable, in the method according to the present invention, in step a), 5-50% by weight IPDI, H12MDI, TMDI, or HDI 0-30% by weight of polyisocyanurate of IPDI, H12MDI, TMDI, or HDI. Polytetramethylene ether glycol having a number-average molecular weight of 5-90% by weight of 1000, 1800, or 2000 g / mol (equivalent to commercially available products PolyTHF 1000, PolyTHF1800, or PolyTHF2000), 0-50% by weight of butanediol and 0.1-10% by weight of zinc octoate A mixture consisting of the above is reacted. Percentages here are based on the total mass of the composition. Subsequently, preferably 5-50% by weight of diethyl malonate (based on the total mass of the composition and diethyl malonate) It may be added, and step b) can be carried out.

[0076] In particular, in the method according to the present invention, in step a), 10-30% by weight IPDI, H12MDI, TMDI, or HDI 0-5% by weight of polyisocyanurate of IPDI, H12MDI, TMDI, or HDI. Polytetramethylene ether glycol having a number-average molecular weight of 1000, 1800, or 2000 g / mol, 20-80% by weight. 0-20% by weight of butanediol and 0.1-7% by weight of zinc octoate A mixture consisting of is reacted. Percentages here are based on the total mass of the composition. Preferably, subsequently, 5-25% by weight of diethyl malonate (based on the total mass of the composition and diethyl malonate) It may be added, and step b) can be carried out.

[0077] Even more preferably, in the method according to the present invention, in step a), 10-30% by weight IPDI, H12MDI, TMDI, or HDI 1-5% by weight of polyisocyanurate of IPDI, H12MDI, TMDI, or HDI. Polytetramethylene ether glycol having a number-average molecular weight of 1000, 1800, or 2000 g / mol, 20-80% by weight. 0-20% by weight of butanediol and 0.1-7% by weight of zinc octoate A mixture consisting of is reacted. Percentages here are based on the total mass of the composition. Preferably, subsequently, 5-25% by weight of diethyl malonate (based on the total mass of the composition and diethyl malonate) It may be added, and step b) can be carried out.

[0078] The present invention also relates to a kit comprising one of the aforementioned prepolymers, which can be obtained by one of the methods described above.

[0079] b) Diamine / Polyamine The one-component system comprises at least one diamine and / or polyamine. The diamine has two amino groups. The polyamine has three or more amino groups. Preferably, the one-component system comprises at least one diamine. Most preferably, the one-component system comprises one diamine. Even more preferably, the diamine is one (cyclic) aliphatic amine or one polyetheramine.

[0080] Preferably, the diamine is isophoronediamine (IPD), 4,4′-diaminodicyclohexylmethane (PACM), 4,4′-methylenebis(2-methylcyclohexaneamine) (DMDC), a mixture of 2,2,4- and 2,4,4-trimethylhexamethylenediamine (TMD), hexanediamine (HDA), 1,3-bis(aminomethyl)cyclohexane (1,3-BAC), and polyoxypropylenediamine. Preferably, the polyoxypropylenediamine is a polyoxypropylenediamine called D-230. Therefore, the diamine may preferably be selected from the group consisting of isophorone diamine (IPD), 4,4′-diaminodicyclohexylmethane (PACM), 4,4′-methylenebis(2-methylcyclohexaneamine) (DMDC), a mixture of 2,2,4- and 2,4,4-trimethylhexamethylenediamine (TMD), hexanediamine (HDA), 1,3-bis(aminomethyl)cyclohexane (1,3-BAC), and polyoxypropylenediamine called D-230.

[0081] The present invention also relates to a method for producing the one-component system, comprising mixing at least one polyurethane prepolymer based on a polyalkylene glycol having a number average molecular weight of 900 to 2150 g / mol and optionally further diols and / or polyols, wherein all unreacted isocyanate groups of the polyurethane prepolymer are blocked with at least one malonic acid ester, with at least one diamine and / or polyamine.

[0082] The present invention also concerns the use of the polyurethane prepolymer according to the present invention for manufacturing artificial leather or (artificial) leather coatings.

[0083] The present invention further relates to a method for producing artificial leather or an artificial leather coating, using the one-component system according to the present invention. Particularly preferably, in this method, a one-component system having exactly one type of diamine or polyamine is used. Most particularly preferably, a system containing one type of diamine is used. Most particularly preferably, a system containing one type of polyurethane prepolymer and one type of diamine is used.

[0084] The method for manufacturing the artificial leather described above is preferably carried out such that the one-component system is applied to a support and then heat-cured. During or after the heat-curing, an embossing step for a surface structure may be provided. The support is preferably a fibrous support, preferably a support containing natural or artificial fibers. More preferably, the support is paper, cotton, or polyester.

[0085] The method for manufacturing the (artificial) leather coating described above is preferably carried out so that the one-component system is applied to a piece of artificial leather or leather and then heat-cured. During or after the heat-curing process, an embossing step for the surface structure may be provided.

[0086] Since the polyurethane prepolymer does not react with the at least one diamine and / or polyamine in the one-component system at room temperature, the one-component system can be stored. [Examples]

[0087] 1. Manufacturing of the prepolymer First, a prepolymer of isophorone diisocyanate and PolyTHF is prepared by reacting the amounts shown in Table 1 in the presence of 0.1% by weight of DBTL at 60°C for 1 hour.

[0088] Subsequently, the diisocyanate prepolymer is produced by reacting the weighed amounts of diethyl malonate (an example according to the present invention) or caprolactam / MEK-oxime (a comparative example) shown in Table 1 with 2.0% by weight of zinc octoate at 80°C for 8 hours.

[0089] 2.Artificial leather manufacturing For the manufacture of (artificial) leather coatings, the obtained blocked prepolymer is mixed with a diamine (PACM or isophorone diamine) and further components in the amounts specified in Table 1, in a laboratory mixer at a temperature of 40°C and a mixing speed of 1200 rpm.

[0090] This material is applied to a release substrate using a film applicator and cured at a temperature of 120-150°C to obtain an (artificial) leather coating.

[0091] The test results of the obtained coatings are summarized in Table 2. Only the malonate-blocked prepolymer yielded the optimal coating in terms of the achieved values ​​of tensile strength, elongation, and modulus of elasticity.

[0092] Table 1 [Table 1] * = Comparative example not based on the present invention IPDI: Isophorone diisocyanate, Evonik Industries AG PolyTHF 1000: PolyTHF (molar mass 1000 g / mol), BASF PolyTHF 650: PolyTHF (molar mass 650 g / mol), BASF PolyTHF 3000: PolyTHF (molar mass 3000 g / mol), BASF PACM: 4,4′-Diaminodicyclohexylmethane, Evonik Industries AG IPDA: Isophoronediamine, Evonik Industries AG Diethyl malonate: Merck MEK oxime and acetylacetone: Merck ε-Caprolactam: BASF TIB Kat 218: TIB Chemicals Coscat 83:Erbsloeh Borchikat 22 and 0761: Borchers Tegoglide B1484: Evonik Industries AG.

[0093] Table 2 [Table 2] Measurement method: Film thickness: DIN EN ISO 2360 Tensile strength, elongation, modulus of elasticity 100%, modulus of elasticity 200%, modulus of elasticity 300%: DIN EN ISO 527.

[0094] The embodiments of the present invention are as follows: 1. A one-component system, a) At least one polyurethane prepolymer based on at least one diisocyanate and / or polyisocyanate and at least one diol and / or polyol, Here, at least one diol or polyol is a polyalkylene glycol having a number-average molecular weight of 900 to 2150 g / mol, and all unreacted isocyanate groups are blocked with at least one malonic acid ester, and b) at least one diamine and / or polyamine The one-component system, including the aforementioned.

[0095] 2. The one-component system according to embodiment 1, characterized in that the prepolymer is diisocyanate-based.

[0096] 3. The one-component system according to embodiment 1 or 2, characterized in that one or at least one of the diisocyanates is a (cyclic) aliphatic diisocyanate.

[0097] 4. The one-component system according to any one of the above embodiments, characterized in that one or at least one of the diisocyanates is selected from HDI, TMDI, H12MDI, IPDI, TMXDI, XDI, MDI, and TDI.

[0098] 5. The one-component system according to embodiment 4, characterized in that one or at least one of the diisocyanates is IPDI.

[0099] 6. The one-component system according to any one of the embodiments, characterized in that the prepolymer is based on one or two, preferably two, diols.

[0100] 7. The one-component system according to embodiment 6, characterized in that the prepolymer is based on a first diol in an amount of 80 to 100% by weight and on a second diol in an amount of 0 to 20% by weight, wherein the weight is based on the total mass of the diol.

[0101] 8. The one-component system according to any one of the above embodiments, characterized in that the polyalkylene glycol is polytetramethylene ether glycol.

[0102] 9. The one-component system according to embodiment 8, characterized in that the number-average molecular weight of the polytetramethylene ether glycol is 950 to 1200 g / mol.

[0103] 10. The one-component system according to any one of embodiments 7 to 9, characterized in that the second diol is a hydrocarbon diol having 2 to 10 carbon atoms.

[0104] 11. The one-component system according to embodiment 10, characterized in that the hydrocarbon diol is selected from the group consisting of ethylene glycol, n-propylene glycol, isopropane glycol, 2-methyl-1,3-propanediol, n-butylene glycol, n-pentyl glycol, n-hexanediol, diethylene glycol, 1,4-cyclohexanedimethanol, tripropylene glycol, and 1,10-decanediol.

[0105] 12. The one-component system according to any one of the above embodiments, characterized in that the at least one malonic acid ester is selected from dimethyl malonate, diethyl malonate, diisopropyl malonate, and monoethyl malonate.

[0106] 13. The one-component system according to embodiment 12, characterized in that the malonic acid ester is diethyl malonate.

[0107] 14. The one-component system according to any one of the above embodiments, characterized in that the diamine and / or polyamine is a diamine and is selected from the group consisting of isophorone diamine, 4,4′-diaminodicyclohexylmethane, 4,4′-methylenebis(2-methylcyclohexaneamine), a mixture of 2,2,4- and 2,4,4-trimethylhexamethylenediamine, hexanediamine, 1,3-bis(aminomethyl)cyclohexane, and polyoxypropylenediamine.

[0108] 15. Use of a one-component system according to any one of the above embodiments for manufacturing artificial leather or an artificial leather coating.

[0109] 16. A method for producing a one-component system according to any one of embodiments 1 to 14, At least one polyurethane prepolymer based on a polyalkylene glycol having a number average molecular weight of 900 to 2150 g / mol and optionally further diols and / or polyols, wherein all unreacted isocyanate groups of the polyurethane prepolymer are blocked with at least one malonic acid ester, At least one diamine and / or polyamine and The method of mixing the two with each other.

[0110] 17. A method for manufacturing artificial leather, comprising applying a one-component system described in any one of embodiments 1 to 14 to a support and then heat-curing it.

[0111] 18. A method for producing an (artificial) leather coating, comprising applying a one-component system described in any one of embodiments 1 to 14 to a piece of artificial leather or leather and then heat-curing it.

Claims

1. It is a one-component system, a) At least one polyurethane prepolymer based on at least one diisocyanate and / or polyisocyanate and at least one diol and / or polyol, Here, at least one diol or polyol is a polyalkylene glycol having a number-average molecular weight of 900 to 2150 g / mol, and all unreacted isocyanate groups are blocked by at least one malonic acid ester, and b) At least one diamine and / or polyamine The one-component system, including the aforementioned.

2. The one-component system according to claim 1, characterized in that the prepolymer is based on diisocyanate.

3. The one-component system according to claim 1 or 2, characterized in that one or at least one diisocyanate is a (cyclic) aliphatic diisocyanate.

4. The one-component system according to claim 1 or 2, characterized in that one or at least one diisocyanate is selected from HDI, TMDI, H12MDI, IPDI, TMXDI, XDI, MDI, and TDI.

5. The one-component system according to claim 4, characterized in that one or at least one diisocyanate is IPDI.

6. The one-component system according to claim 1 or 2, characterized in that the prepolymer is based on one or two diols.

7. The one-component system according to claim 6, characterized in that the prepolymer is based on a first diol in an amount of 80 to 100% by weight and on a second diol in an amount of 0 to 20% by weight, wherein the weight is based on the total mass of the diol.

8. The one-component system according to claim 1 or 2, characterized in that the polyalkylene glycol is polytetramethylene ether glycol.

9. The one-component system according to claim 8, characterized in that the number-average molecular weight of the polytetramethylene ether glycol is 950 to 1200 g / mol.

10. The one-component system according to claim 7, characterized in that the second diol is a hydrocarbon diol having 2 to 10 carbon atoms.

11. The one-component system according to claim 10, characterized in that the hydrocarbon diol is selected from the group consisting of ethylene glycol, n-propylene glycol, isopropane glycol, 2-methyl-1,3-propanediol, n-butylene glycol, n-pentyl glycol, n-hexanediol, diethylene glycol, 1,4-cyclohexanedimethanol, tripropylene glycol, and 1,10-decanediol.

12. The one-component system according to claim 1 or 2, characterized in that the at least one malonic acid ester is selected from dimethyl malonate, diethyl malonate, diisopropyl malonate, and monoethyl malonate.

13. The one-component system according to claim 12, characterized in that the malonic acid ester is diethyl malonate.

14. The one-component system according to claim 1 or 2, characterized in that the diamine and / or polyamine is a diamine and is selected from the group consisting of isophorone diamine, 4,4'-diaminodicyclohexylmethane, 4,4'-methylenebis(2-methylcyclohexaneamine), a mixture of 2,2,4- and 2,4,4-trimethylhexamethylenediamine, hexanediamine, 1,3-bis(aminomethyl)cyclohexane, and polyoxypropylenediamine.

15. Use of the one-component system according to claim 1 or 2 for manufacturing artificial leather or (artificial) leather coatings.

16. A method for producing the one-component system described in claim 1 or 2, At least one polyurethane prepolymer based on a polyalkylene glycol having a number average molecular weight of 900 to 2150 g / mol and optionally further diols and / or polyols, wherein all unreacted isocyanate groups of the polyurethane prepolymer are blocked with at least one malonic acid ester, At least one diamine and / or polyamine The method of mixing the two with each other.

17. A method for manufacturing artificial leather, comprising applying the one-component system described in claim 1 or 2 to a support and then heat-curing it.

18. A method for producing an (artificial) leather coating, comprising applying the one-component system described in claim 1 or 2 to a piece of artificial leather or leather and then heat-curing it.