polyurethane dispersion

Abstract

This invention relates to aqueous polyurethane dispersions containing at least one polyurethane, at least one organic dialkyl dicarbonate, and at least one biocidal compound different from the organic dialkyl dicarbonate, characterized in that the at least one organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or mixtures of at least two of these, further relating to the use of the organic dialkyl dicarbonate for reducing microorganisms in aqueous polyurethane dispersions, to a method for producing aqueous polyurethane dispersions containing reduced amounts of microorganisms, and to articles, cosmetics, coatings, adhesive layers, coating formulations, adhesive formulations, and / or cosmetic formulations obtainable therefrom.

Description

[0001] This invention relates to aqueous polyurethane dispersions containing at least one polyurethane, at least one organic dialkyl dicarbonate, and at least one biocidal compound different from the organic dialkyl dicarbonate. The at least one organic dialkyl dicarbonate is characterized by being selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or mixtures of at least two of these. The invention further relates to the use of the organic dialkyl dicarbonate for reducing microorganisms in aqueous polyurethane dispersions, a method for producing aqueous polyurethane dispersions containing reduced amounts of microorganisms, and articles, cosmetics, coatings, adhesive layers, coating formulations, adhesive formulations, and / or cosmetic formulations obtainable therefrom.

[0002] The use of aqueous polyurethane dispersions, the addition of biocidal agents to preserve polyurethane dispersions, and the use of the corresponding polyurethane dispersions are known to those skilled in the art.

[0003] DE 19810819 discloses a method for treating liquid coatings containing in-can preservatives. For this purpose, an agent for decomposing the in-can preservative is added to the coating just before its use. Isothiazolinones are disclosed as suitable in-can preservatives; examples of suitable in-can preservatives are particularly chloromethylisothiazolinone, methylisothiazolinone, benzisothiazolinone, octylisothiazolinone, or methyltrimethyleneisothiazolinone.

[0004] US 2018 / 258300 discloses a printing press ink composition comprising synthetic resin particles, such as polyurethane particles, pigments, glycol ethers, and water. This composition may contain additives, such as preservatives. The water used to produce the composition may be pretreated with hydrogen peroxide to remove microorganisms.

[0005] US 2017 / 156340 discloses an antimicrobial coating for use on implants, medical devices, equipment, or hospital equipment. For this purpose, a polymer with a metal derivative is adhered to the surface, which exerts a biocidal effect in the presence of hydrogen peroxide.

[0006] JP 2018 053 ​​170 discloses a printing press ink containing a crosslinkable polyurethane dispersion based on a urethane resin. The printing press ink may also contain a preservative. Furthermore, the water used to produce the printing press ink may be pretreated with hydrogen peroxide to make it sterile.

[0007] However, it has been found that peroxides, such as hydrogen peroxide, are incompatible with other biocides that are readily used for in-tank corrosion prevention, such as isothiazolinones, such as 5-chloro-2-methylisothiazolinone and 2-methylisothiazolinone.

[0008] The object of this invention is to provide waterborne polyurethane dispersions that not only exhibit consistently high quality and good performance until processing, particularly for the customer, but are also substantially free of microorganisms such as bacteria, yeasts, and molds during processing, especially for use in the production of articles, cosmetics, coatings, adhesives, or adhesive layers. To ensure the long-term stability of the waterborne polyurethane dispersions, it should be permissible to allow treatment in the presence of established biocides such as isothiazolinones (e.g., 5-chloro-2-methylisothiazolinone and 2-methylisothiazolinone). These can be used for in-tank corrosion protection, but the disadvantage is that the amount available is very limited if one wishes to avoid classifying the final product as a hazardous or harmful substance. Therefore, they are not well-suited as initial germ-reducing biocides. Therefore, in the context of this objective, the compatibility of germ-reducing treatments with isothiazolinones is necessary.

[0009] Another object of the present invention is to provide a method for producing an aqueous polyurethane dispersion containing a reduced amount of microorganisms.

[0010] These objectives are achieved by an aqueous polyurethane dispersion according to the invention, the aqueous polyurethane dispersion containing at least one polyurethane, at least one organic dialkyl dicarbonate, and at least one biocidal compound different from the organic dialkyl dicarbonate, characterized in that the at least one organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or a mixture of at least two of these.

[0011] These objectives are further achieved by a method according to the invention for producing an aqueous polyurethane dispersion containing a reduced amount of microorganisms, the method comprising at least the following steps: (A) Provide an aqueous polyurethane dispersion containing at least one type of polyurethane; (B) Treat the aqueous polyurethane dispersion from step (A) with at least one organic dialkyl dicarbonate, wherein the organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate and / or mixtures of at least two of these. To obtain an aqueous polyurethane dispersion containing a reduced amount of microorganisms.

[0012] These objectives are also achieved by the use of at least one organic dialkyl dicarbonate according to the invention for reducing microorganisms in aqueous polyurethane dispersions containing at least one polyurethane, characterized in that the at least one organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate and / or mixtures of at least two of these.

[0013] In the context of this invention, "reduced microbial quantity" or "for reducing microorganisms" is understood to mean, compared to the CFU density of an untreated polyurethane dispersion, a reduction in the number of microorganisms defined as colony-forming units (CFUs) in the aqueous polyurethane dispersion after 72 hours of growth in the corresponding test system, preferably less than 10,000 CFU / ml, particularly preferably less than 1,000 CFU / ml, and even more preferably less than 100 CFU / ml, in each case according to DIN EN ISO 6222 (K5) 1999-07. However, direct or indirect quantitative methods suitable for the corresponding type of microorganisms can generally be used. For example, in the case of bacteria, BacTrac analysis or surface viable count, plaque determination, or slide test as described in the experimental section can be used. Preferably, the amount of microorganisms is reduced to such a degree that BacTrac 4300 from SY-LAB Geräte GmbH shows no germ load in the aqueous polyurethane dispersion after a test duration of 24 hours, preferably 48 hours, and particularly preferably 72 hours. Compared to the original polyurethane dispersion, the bacterial load based on colony-forming units (CFU) was reduced by at least 80%, preferably at least 99%, as described in the experimental section of this document, using a BacTrac 4300 from SY-LAB Geräte GmbH. This is based on the microbial load in the aqueous polyurethane dispersion at the start of the measurement (time 0). For this purpose, 1 mL of polyurethane-polyurea-polyurethane dispersion was poured into a BiMedia 001C measuring cell (order number 41-440011). The measuring cell was sealed with a nut (order number 41-440012+) and placed in the measurement unit of the BacTrac 4300, which was maintained at 30°C.

[0014] Surprisingly, it has been found that the aqueous polyurethane dispersions according to the invention, as a result of initial pathogen reduction or elimination, optionally combined with in-can preservatives and biocides, remain sterile for at least 6 months, provided they are in the initially sealed container. Aqueous polyurethane dispersions that are not applicable under current technology can also be used here, because classic biocide treatment of polyurethane dispersions would require such high amounts of biocide that it would be necessary to apply chemical regulatory labeling to the resulting polyurethane dispersions, which is generally unacceptable.

[0015] The present invention will now be described in detail.

[0016] In the context of this invention, the word “a” associated with countable parameters is understood to mean a number only when explicitly stated (e.g., by stating “exactly a”). When referred to below, for example, as “a polyisocyanate,” the word “a” should be understood to mean only the indefinite article, not the number 1, and thus also covers embodiments in which two or more (e.g., structurally dissimilar) polyisocyanates are present.

[0017] In the context of this invention, "aqueous polyurethane dispersion" is understood to mean an aqueous polyurethane dispersion, an aqueous emulsion, an aqueous suspension, or an intermediate state / form thereof, preferably an aqueous polyurethane dispersion, an aqueous emulsion, and / or an aqueous suspension. The term "polyurethane dispersion" is particularly preferably understood to mean an aqueous emulsion and / or an aqueous suspension. The term "polyurethane dispersion" refers to both polyurethane dispersions and polyurethane-(poly)urea-polyurethane dispersions. The term "polyurethane" refers to both polyurethane and polyurethane-(poly)urea.

[0018] In the context of this invention, the term "microorganism" is understood to mean, for example, algae, bacteria, fungi, yeast and viruses, preferably bacteria, fungi and yeast, and even more preferably bacteria and / or yeast.

[0019] According to the invention, the terms "comprising" or "containing" preferably mean "consisting substantially of," and particularly preferably "consisting of." It should be noted that features listed individually in the claims can be combined with each other in any technically advantageous manner (even across class boundaries, e.g., between methods and apparatuses), and further configurations of the invention are specified. The specification also provides a feature description and detailed description of the invention.

[0020] It should also be noted that the conjunction “and / or” used herein to connect two features and to connect them is always interpreted in such a way that in the first configuration of the subject matter of the invention, only the first feature exists; in the second configuration, only the second feature may exist; and in the third configuration, both the first and second features may exist.

[0021] The aqueous polyurethane dispersion according to the present invention contains at least one polyurethane, at least one organic dialkyl dicarbonate, and at least one compound with biocidal activity other than the organic dialkyl dicarbonate, characterized in that the at least one organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or a mixture of at least two of these.

[0022] In a preferred embodiment, the aqueous polyurethane dispersion is an aqueous polyurethane dispersion containing a reduced amount of microorganisms.

[0023] According to the present invention, any polyurethane known to those skilled in the art can generally be used in aqueous polyurethane dispersions.

[0024] In a preferred embodiment, at least one polyurethane has been or is available through the reaction of the following synthetic components: (a) At least one diol and / or polyol component; (b) at least one diisocyanate and / or polyisocyanate component; (c) At least one component containing at least one hydrophilic group; (d) Optional mono-, di-, and / or triamino-functionalized and / or hydroxyamino-functionalized compounds; and (e) Other isocyanate reactive compounds may be selected; Components (a), (b), (c), (d), and (e) are different.

[0025] Suitable diol and / or polyol component (a) is a compound having at least two isocyanate reactive hydrogen atoms and a number-average molecular weight (determined by GPC at 23°C with THF as eluent and calibrated using polystyrene standards) preferably from 62 to 18000 g / mol, particularly preferably from 62 to 4000 g / mol.

[0026] Examples of suitable structural components (a) are polyether polyols, polyester polyols, polycarbonate polyols, polylactones, and polyamides. Preferred polyols (a) preferably have 2 to 4, particularly preferably 2 to 3 hydroxyl groups, especially preferably 2 hydroxyl groups. Mixtures of various such compounds are also considered.

[0027] Although the teachings of this invention can be implemented in principle with any dispersed polyurethane or polyurethane-urea polymer, at least one polyurethane present in the aqueous polyurethane dispersion according to the invention preferably comprises one or more polyester polyols and / or one or more polyether polyols and / or one or more polycarbonate polyols as component (a). In a preferred embodiment, at least one polyurethane is based on polyether polyols and / or polyester polyols and / or polycarbonate polyols. In a further preferred embodiment, at least one polyurethane is based on at least one polyester polyol, preferably polyester diol, and / or at least one polyether polyol, preferably polyether diol, and / or at least one polycarbonate polyol, preferably polycarbonate diol.

[0028] Suitable polyester polyols, especially linear polyester diols or sparsely branched polyester polyols, can be derived from aliphatic, alicyclic, or aromatic dicarboxylic acids or polycarboxylic acids, such as succinic acid, methyl succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, azelaic acid, sebacic acid, nonanedicarboxylic acid, decanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, cyclohexanedicarboxylic acid, maleic acid, fumaric acid, malonic acid, or trimellitic acid and anhydrides, such as phthalic anhydride, trimellitic anhydride, or succinic anhydride, or mixtures thereof, with polyols, such as ethylene glycol, di-, Tri-, tetraethylene glycol, propylene-1,2-diol, di-, tri-, tetrapropylene glycol, propylene-1,3-diol, butane-1,4-diol, butane-1,3-diol, butane-2,3-diol, pentane-1,5-diol, hexane-1,6-diol, 2,2-dimethylpropane-1,3-diol, 1,4-dihydroxycyclohexane, 1,4-dimethylolcyclohexane, octane-1,8-diol, decane-1,10-diol, dodecane-1,12-diol, or mixtures thereof, optionally with the additional use of higher functional polyols such as trimethylolpropane, glycerol, or pentaerythritol produced in a known manner. Alicyclic and / or aromatic dihydroxy and polyhydroxy compounds are also suitable as polyols for the production of polyester polyols. Instead of free polycarboxylic acids, the corresponding polycarboxylic anhydrides or the corresponding low-carbon alcohol esters of polycarboxylic acids, or mixtures thereof, can also be used in the production of polyesters.

[0029] Polyester polyols can also be homopolymers or copolymers of lactones, preferably obtained by addition reactions of lactones or mixtures of lactones, such as butyrolactone, ε-caprolactone, and / or methyl-ε-hexadecanolactone, to suitable bifunctional and / or higher-functional starting molecules, such as the low molecular weight polyols mentioned above as components in the synthesis of polyester polyols. Preferred are the corresponding polymers of ε-caprolactone.

[0030] Hydroxyl-containing polycarbonates are also suitable as polyhydroxy components (a), for example, those produced by reacting diols, such as butane-1,4-diol and / or hexane-1,6-diol, with diaryl carbonates, such as diphenyl carbonate, dialkyl carbonates, such as dimethyl carbonate, or phosgene. If the polyurethane dispersion according to the invention is used in the production of adhesives, the hydrolysis resistance of the polyurethane or polyurethane-urea-polyurethane dispersion adhesive can be improved by at least partially using a hydroxyl-containing polycarbonate.

[0031] Suitable examples of polyether polyols are addition polymers of styrene oxides, ethylene oxide, propylene oxide, tetrahydrofuran, butylene oxide, epichlorohydrin, and their mixed addition and graft products, as well as polyether polyols obtained by condensation of polyols or mixtures thereof and by alkoxylation of polyols, amines, and amino alcohols. Polyether polyols particularly suitable as structural component (a) are homopolymers, copolymers, and graft polymers of propylene oxide, ethylene oxide, and tetrahydrofuran, which can be obtained by addition of the aforementioned epoxides or tetrahydrofurans to low molecular weight diols or triols, such as those mentioned above as structural components of polyester polyols, or by addition to higher functional low molecular weight polyols, such as pentaerythritol or sugars, or by addition to water.

[0032] Suitable components (a) are low molecular weight diols, triols, and / or tetraols, such as ethylene glycol, di-, tri-, tetraethylene glycol, propylene-1,2-diol, di-, tri-, tetrapropylene glycol, propylene-1,3-diol, butan-1,4-diol, butan-1,3-diol, butan-2,3-diol, pentan-1,5-diol, hexan-1,6-diol, 2,2-dimethylpropan-1,3-diol, 1,4-dihydroxycyclohexane, 1,4-dihydroxymethylcyclohexane. Hexane, oct-1,8-diol, dec-1,10-diol, dodecane-1,12-diol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-diethanol, 1,4-, 1,3-, 1,2-dihydroxybenzene or 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), TCD glycol, trimethylolpropane, glycerol, pentaerythritol, dipentaerythritol or mixtures thereof, optionally with other diols or triols not mentioned.

[0033] The polyol used can also be the polyol mentioned above, especially the reaction product of low molecular weight polyols with ethylene oxide and / or propylene oxide.

[0034] The low molecular weight component (a) preferably has a molecular weight of 62 to 400 g / mol and is further preferably used in combination with the above-mentioned polyester polyol, polylactone, polyether polyol and / or polycarbonate polyol.

[0035] The polyol component (a) is preferably present in an amount of 20% to 94% by weight, particularly preferably in an amount of 30% to 90% by weight, and very particularly preferably in an amount of 65% to 90% by weight in at least one polyurethane used according to the invention, wherein the sum of components (a), (b), (c), optional (d) and optional (e) in each case is 100% by weight.

[0036] Suitable component (b) includes any organic compound having at least two free isocyanate groups per molecule. Preferably, a diisocyanate of the general formula Y(NCO)2 is used, wherein Y is a divalent aliphatic hydrocarbon group having 4 to 12 carbon atoms, a divalent alicyclic hydrocarbon group having 6 to 15 carbon atoms, a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, or a divalent aryliphatic hydrocarbon group having 7 to 15 carbon atoms.

[0037] Preferred examples of such diisocyanates include tetramethylene diisocyanate, methylpentamethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 1-isocyano-3,3,5-trimethyl-5-isocyanate-methylcyclohexane (isophorone diisocyanate; IPDI), 4,4'-dicyclohexylmethane diisocyanate, and 4,4'-diisocyanate-2,2- Dicyclohexylpropane, 1,4-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'- and 2,4'-diphenylmethane diisocyanate, tetramethylxylylenediisocyanate, p-xylylylenediisocyanate, p-isopropylidene diisocyanate, and mixtures thereof.

[0038] In addition to these simple diisocyanates, polyisocyanates containing heteroatoms in the groups linking the isocyanate groups and / or having a functionality of more than two isocyanate groups per molecule are also suitable. The former are polyisocyanates having structures such as urea diketone, isocyanurate, carbamate, urethane, biuret, carbodiimide, iminooxadiazine diketone, and / or oxadiazine triketone, which are produced, for example, by modification of simple aliphatic, alicyclic, aryliphatic, and / or aromatic diisocyanates and consist of at least two diisocyanates. An example of an unmodified polyisocyanate having more than two isocyanate groups per molecule is, for example, 4-isocyanate-methyloctane 1,8-diisocyanate (nonane triisocyanate).

[0039] Preferred diisocyanates (b) are pentamethylene diisocyanate, methylpentamethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 1-isocyano-3,3,5-trimethyl-5-isocyano-methylcyclohexane, 4,4'-dicyclohexylmethane diisocyanate, 1,3- and 1,4-bis(isocyano-methyl)benzene, 1,3- and 1,4-bis(1-isocyano-1-methylethyl)benzene, and bis(isocyanate-1-methylethyl)benzene. (4-(1-isocyanate-1-methylethyl)phenyl) ester, 4,4'-diisocyanate-2,2-dicyclohexylpropane, 1,4-phenyl diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'- and 2,4'-diphenylmethane diisocyanate, tetramethylxylene diisocyanate, p-xylene diisocyanate, p-isopropylene diisocyanate, and mixtures thereof.

[0040] Particularly preferred component (b) is 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, hexamethylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1-isocyanate-3,3,5-trimethyl-5-isocyanate-methylcyclohexane, and mixtures thereof.

[0041] Component (b) is present in at least one polyurethane used according to the invention in an amount of typically 5% to 60% by weight, preferably 6% to 45% by weight, and particularly preferably 7% to 25% by weight, wherein the sum of components (a), (b), (c), optional (d) and optional (e) in each case is 100% by weight.

[0042] Suitable component (c) is, for example, a component containing a sulfonate or carboxylate group, such as a diamino or dihydroxy compound having a sulfonate and / or carboxylate group, for example, N-(2-aminoethyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-3-aminopropanesulfonic acid, N-(2-aminoethyl)-3-aminopropanesulfonic acid, similar carboxylic acids, dimethylolpropionic acid, dimethylolbutyric acid, sodium, lithium, potassium, or tertiary amine salt of the reaction product of 1 mole of a diamine such as ethane-1,2-diamine or isophorone diamine with 2 moles of acrylic acid or maleic acid in the sense of Michael addition.

[0043] The acids are preferably used directly as their salts, either sulfonates or carboxylates. However, some or all of the neutralizing agents necessary for salt formation may also be added only during or after polyurethane production.

[0044] Tertiary amines particularly suitable and preferred for salt formation include, for example, triethylamine, dimethylcyclohexylamine, and / or ethyldiisopropylamine. Other amines may also be used for salt formation, such as ammonia, diethanolamine, triethanolamine, dimethylethanolamine, methyldiethanolamine, and aminomethylpropanol, as well as mixtures of the listed amines and other amines. These amines are advantageously added only after the prepolymer composed of components (a) and (b) has been formed.

[0045] Other neutralizing agents, such as hydroxides of sodium, potassium, lithium, and calcium, can also be used for neutralization purposes.

[0046] Another suitable component (c) is a nonionic hydrophilic monofunctional or bifunctional polyether based on an alcohol or amine-based ethylene oxide polymer or ethylene oxide / propylene oxide copolymer, such as polyether LB 25 (Covestro Deutschland AG, Leverkusen, Germany), a diol with a polyether side chain containing an ethylene oxide unit (e.g., YmerN120, Perstorp Holding AB, Malmö, Sweden), or MPEG 750, i.e., a methoxylated polyethylene glycol with a molecular weight of 750 g / mol, for example, available under the trade name Pluriol® 750 from BASF SE, Germany.

[0047] The preferred component (c) is N-(2-aminoethyl)-2-aminoethane sulfonate, N-(2-aminoethyl)-2-aminoethane carboxylate, and salts of dimethylolpropionic acid and dimethylolbutyric acid.

[0048] Component (c) is present in at least one polyurethane used according to the invention in an amount preferably from 0.1% to 15% by weight, particularly preferably from 0.5% to 10% by weight, very particularly preferably from 0.8% to 5% by weight, and even more preferably from 0.9% to 3.0% by weight, wherein the sum of components (a), (b), (c), optional (d) and optional (e) in each case is 100% by weight.

[0049] According to the invention, suitable component (d) is a mono-, di-, or trifunctional amine and / or a mono-, di-, or trifunctional hydroxylamine, such as aliphatic and / or alicyclic primary and / or secondary monoamines, such as ethylamine, diethylamine, isopropylamine and butylamine, higher linear aliphatic monoamines and alicyclic monoamines, such as cyclohexylamine. Further examples are amino alcohols, i.e., compounds containing both an amino group and a hydroxyl group in the same molecule, such as ethanolamine, N-methylethanolamine, diethanolamine, diisopropanolamine, 1,3-diamino-2-propanol, N-(2-hydroxyethyl)ethylenediamine, N,N-bis(2-hydroxyethyl)ethylenediamine, and 2-propanolamine.

[0050] Further examples are diamines and triamines, such as ethylene-1,2-diamine, hexamethylene-1,6-diamine, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane (isophorone diamine), piperazine, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, and diethylenetriamine. Also suitable are adipic acid dihydrazide, hydrazine, and hydrazine hydrate. Of course, mixtures of the various compounds (d) mentioned can also be used, optionally in conjunction with compounds (d) not mentioned.

[0051] Preferred component (d) is ethylene-1,2-diamine, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, diethylenetriamine, diethanolamine, ethanolamine, N-(2-hydroxyethyl)ethylenediamine and N,N-bis(2-hydroxyethyl)ethylenediamine.

[0052] Component (d) is used as a di- or trifunctional chain extender, preferably for constructing higher molecular weights, or as a monofunctional compound to limit molecular weight and / or optionally as a means of incorporating additional reactive groups (such as free hydroxyl groups). If (poly)amine (d) is not used, the resulting polymer is pure polyurethane, more preferably free of urea groups.

[0053] Component (d) is preferably present in at least one polyurethane used according to the invention in an amount of 0% to 10% by weight, particularly preferably 0% to 5% by weight, and very particularly preferably 0.2% to 3% by weight, wherein the sum of components (a), (b), (c), optional (d) and optional (e) in each case is 100% by weight.

[0054] The component (e) that may be used in combination according to the invention may be, for example, an aliphatic, alicyclic or aromatic monool having 2 to 22 carbon atoms, such as ethanol, butanol, hexanol, cyclohexanol, isobutanol, benzyl alcohol, stearyl alcohol, 2-ethylethanol.

[0055] Component (e) may preferably be present in at least one polyurethane used according to the invention in an amount of 0% to 20% by weight, particularly preferably 0% to 10% by weight, wherein the sum of components (a), (b), (c), optional (d) and optional (e) in each case is 100% by weight.

[0056] Side and / or terminal carboxyl groups can, in principle, be incorporated into the polymer backbone via any of the synthetic components (a) to (e). They are preferably incorporated via components (c), (d), and / or (e).

[0057] Incorporation via component (c) can be achieved, for example, by using dimethylolpropionic acid or dimethylolbutyric acid in the absence of a neutralizing agent or by adding a neutralizing agent in a substoichiometric amount.

[0058] Suitable compounds for component (d) that incorporate a carboxyl group are, for example, compounds containing only one isocyanate-reactive amino group and thus generating a terminal carboxyl group by reacting with the isocyanate component in the production of the polyurethane according to the invention. Linear aliphatic, branched aliphatic, aliphatic-aromatic, and aromatic aminocarboxylic acids are suitable. Examples include aminocarboxylic acids having a primary or secondary amino group, such as alanine, 6-aminohexanoic acid, aminoundecanoic acid, 8-aminooctanoic acid, 5-aminovaleric acid, 4-aminobutyric acid, aminobenzoic acid, 4-aminomethylcyclohexanecarboxylic acid, 2-aminohexanoic acid, 4-aminocyclohexanecarboxylic acid, 12-aminododecanoic acid, and / or 9-aminononanoic acid.

[0059] Compounds suitable for incorporating carboxyl groups as component (d) are, for example, diaminocarboxylic acids, each having two isocyanate-reactive amino groups and thus generating side carboxyl groups in the production of at least one polyurethane by reacting with the isocyanate component. Examples of these are lysine, arginine, and / or histidine.

[0060] Compounds suitable for incorporation of a carboxyl group as component (e) are, for example, hydroxycarboxylic acids containing only one hydroxyl group, such as hydroxypentanoic acid, glycolic acid, and / or 2-hydroxypropionic acid.

[0061] The production of the aqueous polyurethane dispersion according to the invention can be carried out using all methods known in the art, such as the emulsifier-shear method, the acetone method, the prepolymer mixing method, the melt emulsification method, the ketimine method, and the solid spontaneous dispersion method or derivative methods thereof. A summary of these methods can be found in *Methoden der organischen Chemie* (Houben-Weyl, *Erweiterungs- und Folgebände zur 4. Auflage*, Vol. E20, H. Bartl and J. Falbe, *Stuttgart*, New York, Thieme 1987, pp. 1671-1682). According to the invention, the melt emulsification method, the prepolymer mixing method, and the acetone method are preferred. The acetone method is particularly preferred. The use and implementation of the acetone method are prior art and are known to those skilled in the art, for example, from EP-A 0 232 778.

[0062] In a preferred embodiment, in each case, at least one polyurethane is present in an amount of 5% to 64% by weight, preferably 30% to 60% by weight, particularly preferably 40% to 50% by weight, based on the total aqueous polyurethane dispersion.

[0063] In a preferred embodiment, in each case, the water content of the aqueous polyurethane dispersion according to the invention is from 36% to 95% by weight, preferably from 40% to 70% by weight, and particularly preferably from 50% to 60% by weight, based on the total aqueous polyurethane dispersion.

[0064] The aqueous polyurethane dispersion according to the invention contains at least one compound having biocidal activity. In the context of this invention, "having biocidal activity" means that the corresponding compound can control microorganisms, particularly bacteria and / or fungi, prevent their reproduction, or kill them, and must appear in the list of relevant substances and the list of suppliers of relevant substances and products as described in Article 95 of the Biocidal Agents Regulation (BPR) [Regulation (EU) No. 334 / 2014, 11 March 2014] (Version 20.03.2024). At least one compound having biocidal activity is different from an organic dialkyl dicarbonate.

[0065] Suitable compounds with biocidal activity include all biocides known to those skilled in the art, such as algaecides, fungicides, fungicides against fungi, insecticides, antifungals against yeast, and antivirals.

[0066] The biocidal compound preferably comprises one or more bactericides, fungicides targeting fungi, antifungals targeting yeasts, and / or mixtures of at least two of these. Preferably, the biocidal compound used is at least one biocidal agent used for in-can preservation.

[0067] In a preferred embodiment, at least one biocidal compound is a fungicide, antifungal agent, and / or algaecide, preferably at least one isothiazolinone, particularly preferably selected from chloromethylisothiazolinone (CMIT), methylisothiazolinone (MIT), benzisothiazolinone, octylisothiazolinone, butylbenzisothiazolinone, dichlorooctylisothiazolinone, and / or mixtures of at least two of these, and even more preferably selected from 5-chloro-2-methylisothiazolinone / 2-methylisothiazolinone and / or mixtures thereof. The at least one biocidal compound is different from at least one organic dialkyl dicarbonate ester.

[0068] In a preferred embodiment, at least one biocidal compound is present in an amount of 1 to 1000 mg / kg, based on the total aqueous polyurethane dispersion.

[0069] At least one organic dialkyl dicarbonate has the formula R−O−C(=O)−O−C(=O)−O−R´, wherein R and R' are alkyl groups, and R and R' are preferably the same. Examples include dimethyl dicarbonate, diethyl dicarbonate, and ditert-butyl dicarbonate, preferably dipropyl dicarbonate and dibutyl dicarbonate, and very particularly preferably dimethyl diformate.

[0070] In a preferred embodiment, the at least one organic dialkyl dicarbonate is dimethyl dicarbonate, diethyl dicarbonate, and / or a mixture thereof, preferably dimethyl dicarbonate.

[0071] In a preferred embodiment, at least one organic dialkyl dicarbonate is present in an amount of 0.1 g / kg to 50 g / kg, preferably 0.1 g / kg to 20 g / kg, based on the total aqueous polyurethane dispersion.

[0072] In addition to the components described above, the aqueous polyurethane dispersions according to the present invention may also contain any components deemed suitable by those skilled in the art. Examples of additional components include binders, additives and auxiliaries known in coating and adhesive technologies, particularly emulsifiers and light stabilizers, especially UV absorbers, as well as fillers and auxiliaries, particularly antisettling agents, defoamers and / or wetting agents, flow aids, reactive diluents, plasticizers, neutralizers, catalysts, auxiliary solvents, thickeners, additives, especially pigments, dyes or matting agents, tackifiers (so-called thickeners) or mixtures thereof.

[0073] In a preferred embodiment, the aqueous polyurethane dispersion further contains components selected from adhesives, additives and auxiliaries, fillers, auxiliaries, flow aids, reactive diluents, plasticizers, neutralizers, catalysts, auxiliary solvents, thickeners, additives, tackifiers, and mixtures thereof.

[0074] The present invention further relates to a method for producing an aqueous polyurethane dispersion containing a reduced amount of microorganisms, comprising at least the following steps: (A) Provide an aqueous polyurethane dispersion containing at least one type of polyurethane; (B) Treat the aqueous polyurethane dispersion from step (A) with at least one organic dialkyl dicarbonate, wherein the organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate and / or mixtures of at least two of these. To obtain an aqueous polyurethane dispersion containing a reduced amount of microorganisms.

[0075] Details and preferred embodiments of the organic dialkyl dicarbonate and at least one compound having biocidal activity have been further described above and are accordingly applicable to the method according to the invention.

[0076] Details and preferred embodiments of the aqueous polyurethane dispersion provided in step (A) of the method according to the invention have been further described above and are accordingly applicable to the method according to the invention. The aqueous polyurethane dispersion contains varying amounts of microorganisms, provided that the dispersion was not produced and packaged under aseptic conditions. The aqueous polyurethane dispersion provided in step (A) contains at least one polyurethane and microorganisms. The difference between the aqueous polyurethane dispersion provided in step (A) and the aqueous polyurethane dispersion obtained in step (B) is that the amount of microorganisms in the aqueous polyurethane dispersion after step (B) is reduced compared to the aqueous polyurethane dispersion provided in step (A).

[0077] In the context of this invention, "provided" means that the aqueous polyurethane dispersion may be present in any form that a person skilled in the art would consider suitable, and that it may be processed according to step (B) of the method according to the invention. The aqueous polyurethane dispersion is preferably in a container or reactor, such as a stirred reactor. The addition of at least one organic dialkyl dicarbonate may further occur after the aqueous polyurethane dispersion has been transferred to a mixing vessel (particularly a mixing vessel equipped with a stirrer or recirculation pump). The addition of at least one organic dialkyl dicarbonate and the treatment of the aqueous polyurethane dispersion with at least one organic dialkyl dicarbonate may also be carried out directly in the delivery vessel of the polyurethane dispersion.

[0078] According to the invention, the aqueous polyurethane dispersion has the component concentrations further described above. However, according to the invention, the aqueous polyurethane dispersion may also be diluted or concentrated prior to step (A). In each case, based on the total aqueous polyurethane dispersion, a suitable concentration of at least one polyurethane present herein is 5% to 64% by weight, preferably 30% to 60% by weight, and very particularly preferably 40% to 50% by weight.

[0079] In a preferred embodiment, in each case, the water content in the aqueous polyurethane dispersion prior to step (A) is from 36% to 95% by weight, preferably from 40% to 70% by weight, and particularly preferably from 50% to 60% by weight, based on the total aqueous polyurethane dispersion.

[0080] According to the present invention, prior to step (B) of the method according to the present invention, the aqueous polyurethane dispersion may be mixed with at least one other aqueous polymer dispersion, for example, with an aqueous polyurethane dispersion of at least one other film-forming polymer.

[0081] Step (B) of the method according to the invention can generally be carried out at any temperature deemed suitable by those skilled in the art. In a preferred embodiment, step (B) is carried out at 1°C to 100°C, preferably at 5°C to 50°C, and particularly preferably at 10°C to 30°C.

[0082] Step (B) of the method according to the invention can generally be carried out at any pressure that is deemed suitable by those skilled in the art, preferably at atmospheric pressure.

[0083] In step (B), the aqueous polyurethane dispersion may preferably be stirred, particularly using instruments known to those skilled in the art, especially propeller stirrers, anchor stirrers, dissolver discs, spiral stirrers, and jet stirrers, such as Visco jet®. The mixing and / or dissolving in step (B) of the method according to the invention may also be carried out by pumping the recirculated aqueous polyurethane dispersion (A) using, for example, a peristaltic pump, a diaphragm pump, or an eccentric screw pump.

[0084] In the treatment of step (B), the reaction of at least one organic dialkyl dicarbonate in water (i.e., hydrolysis with water in the polyurethane dispersion) releases at least one alcohol. Examples include the release of ethanol from diethyl dicarbonate or methanol from dimethyl dicarbonate. These alcohols can be removed from the product, for example, by distillation, or optionally may be retained wholly or partially in the product mixture. Carbon dioxide formed in the reaction of at least one organic dialkyl dicarbonate in water (i.e., hydrolysis with water in the polyurethane-polyurea-polyurethane dispersion) remains physically dissolved in the polyurethane dispersion, reacts with water to form carbonic acid or carbonates, and / or can be removed from the polyurethane dispersion. The formed carbon dioxide can be partially or completely removed by heating the polyurethane dispersion or by applying a vacuum.

[0085] The reaction time following the addition of at least one organic dialkyl dicarbonate to the polyurethane-polyurea dispersion is preferably from 1 minute to 24 hours. During this time, the batch is preferably actively mixed, for example, by stirring. A post-reaction stage can also be provided without active stirring, and this stage can also be carried out in a delivery vessel.

[0086] Before adding at least one organic dialkyl dicarbonate to an aqueous polyurethane dispersion, the dialkyl dicarbonate can be dissolved in a suitable solvent. Examples include solvents miscible with water, such as water, monohydric alcohols (e.g., methanol or ethanol), glycols (e.g., propylene glycol), ketones (e.g., acetone), or N-alkylpyrrolidones (e.g., N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, or N-butyl-2-pyrrolidone). Solvents that do not decompose or deactivate the dialkyl dicarbonate are preferred.

[0087] Other additives may be added to the aqueous polyurethane dispersion before the dialkyl dicarbonate is added. In a preferred variant, the dialkyl dicarbonate is added in pure form, i.e., without further premixing or pre-dilution.

[0088] In one preferred embodiment, the metering of at least one organic dialkyl dicarbonate is achieved via a nozzle. In another preferred embodiment, the metering of at least one organic dialkyl dicarbonate is achieved via a mixing instrument. In yet another preferred embodiment, the amount and rate of addition of at least one organic dialkyl dicarbonate are controlled by using a liquid flow meter unit and a metering unit coupled thereto.

[0089] Step (B) of the method according to the invention provides an aqueous polyurethane dispersion substantially free of the organic dialkyl dicarbonate used. In a preferred embodiment, 24 hours, preferably 12 hours, more preferably 6 hours, even more preferably 3 hours, and most preferably 1 hour after step (B) of the method according to the invention, the aqueous polyurethane dispersion no longer contains any organic dialkyl dicarbonate, wherein the content of dialkyl dicarbonate is determined by chromatography, preferably by HPLC (high performance liquid chromatography). The obtained aqueous polyurethane dispersion preferably no longer contains any organic dialkyl dicarbonate before its application or use.

[0090] According to the present invention, at least one compound with biocidal activity, different from organic dialkyl dicarbonate, may be added before, after, or simultaneously with step (B). This has the advantage that the amount of microorganisms can be further reduced, and the period during which the polyurethane dispersion contains only a small amount of microorganisms is significantly extended again.

[0091] In a preferred embodiment, at least the following steps (C) are performed before, after, or simultaneously with step (B): (C) Add at least one compound having biocidal activity, which is different from the at least one organic dialkyl dicarbonate, wherein step (C) is preferably performed before or simultaneously with step (B).

[0092] However, according to the present invention, the aqueous polyurethane dispersion obtained in step (B) or step (C) can also be fed into a further workup step, such as by adding thickeners, pigments, color pastes, other processing aids suitable for further processing, such as defoamers, wetting aids, coagulants, and / or stabilizers, such as other antioxidants and UV stabilizers. The methods for adding the aforementioned components are known to those skilled in the art.

[0093] According to the present invention, the aqueous polyurethane dispersion can be used in the production of articles, cosmetics, coatings, adhesive layers or adhesives after step (B) or step (C), wherein if step (C) is present, step (C) must be performed after step (B) or simultaneously with step (B).

[0094] In a preferred embodiment, at least the following step (D) is performed after step (B) or step (C): (D) Production of articles, cosmetics, coatings; adhesive layers or adhesives from the aqueous polyurethane dispersion containing a reduced amount of microorganisms obtained in step (B) or step (C).

[0095] In another preferred embodiment, if step (C) is performed after step (B), then at least the following step (D) is performed after step (A): (D) Production of articles, cosmetics, coatings; adhesive layers or adhesives from the aqueous polyurethane dispersion containing a reduced amount of microorganisms obtained in step (B) or step (C).

[0096] The appropriate methods performed in step (D) of the method of the present invention are known to those skilled in the art, for example... • Dipping, especially for the manufacture of gloves, is preferred for the medical field. • Production of waterborne adhesive polyurethane dispersions, processed with and without crosslinking agents, such as isocyanates or polycarbodiimides. • To produce potentially reactive adhesive layers, adhesive films, or adhesive powders, as described, for example, in EP-A 0 922720 or EP 2 099 840 B1. • Production and / or coating of textiles, leather or synthetic leather, as well as microfiber-based textiles or synthetic leather. • Use polyurethane dispersions in products such as hairspray and sunscreen. • Coatings on plastics, metals, wood, composites, ceramics, and mineral substrates (such as stone) • And on previously coated substrates.

[0097] Preferred articles according to the invention are selected from, for example, articles produced by dip coating, such as disposable gloves or condoms, for medical devices, probes, endoscopes, coated textiles, bandages, wound dressing films, medical foams or so-called wearable patch covers or so-called sleeves.

[0098] The cosmetic products preferred according to the present invention are selected from, for example, hairspray, sunscreen, conditioner or mascara, etc., and at least one polyurethane used herein is more preferably used as a film-forming agent.

[0099] The preferred coatings according to the present invention are selected from, for example, primer, filler, base coat and topcoat systems, coatings for wood, metal and plastic, textiles, leather, and artificial leather, each of which are used in various industries, such as automobiles, large vehicles, ACE (agricultural, construction & earthmoving equipment), industrial painting, furniture or fiberglass sizing.

[0100] The preferred adhesives according to the invention are selected, for example, polyurethane dispersion adhesives processed into one-component or two-component systems, non-reactive and reactive adhesive films, adhesive powders or adhesive layers, which are applied to the surface of a substrate in each case.

[0101] The present invention also relates to an aqueous polyurethane dispersion comprising microorganisms that are available or obtained in reduced amounts by the method of the present invention.

[0102] The present invention also relates to an aqueous polyurethane dispersion containing at least one polyurethane and optionally at least one compound having biocidal activity, characterized in that, after growth in a test system for 72 hours, the number of microorganisms in the aqueous polyurethane dispersion (defined as colony-forming units (CFU)) is less than 10,000 CFU / ml, preferably less than 1,000 CFU / ml, particularly preferably less than 100 CFU / ml, in each case according to DIN EN ISO 6222 (K5) 1999-07.

[0103] The present invention further relates to the use of at least one organic dialkyl dicarbonate ester for reducing microorganisms in an aqueous polyurethane dispersion containing at least one polyurethane, characterized in that the at least one dialkyl dicarbonate ester is selected from dimethyl dicarbonate, diethyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or mixtures of at least two of these. Prior to treatment / use with the organic dialkyl dicarbonate ester, the aqueous polyurethane dispersion contains at least one polyurethane and microorganisms.

[0104] Details and preferred embodiments of the aqueous polyurethane dispersion, the organic dialkyl dicarbonate, and at least one compound having biocidal activity have been further described above and are accordingly applicable to the use according to the invention.

[0105] In a preferred embodiment, the aqueous polyurethane dispersion further contains at least one biocidal compound other than an organic dialkyl dicarbonate.

[0106] The present invention also relates to the use of at least one organic dialkyl dicarbonate according to the invention in the method according to the invention for reducing the amount of microorganisms in an aqueous polyurethane dispersion.

[0107] The present invention also relates to the use of at least one organic dialkyl dicarbonate ester according to the invention in a method for reducing the amount of microorganisms in an aqueous polyurethane dispersion. The steps of the method for reducing the amount of microorganisms in an aqueous polyurethane dispersion may be the same as those described above.

[0108] The present invention also relates to articles, cosmetics, coatings, adhesive layers, coating formulations, adhesive formulations and / or cosmetic formulations containing at least one aqueous polyurethane dispersion according to the present invention or an aqueous polyurethane dispersion according to the present invention containing a reduced amount of microorganisms.

[0109] The various aspects of the subject matter described herein are set forth in the following numbered clauses: Clause 1. An aqueous polyurethane dispersion comprising at least one polyurethane, at least one organic dialkyl dicarbonate, and at least one biocidal compound other than said organic dialkyl dicarbonate, characterized in that said at least one dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or a mixture of at least two of these.

[0110] Clause 2. The aqueous polyurethane dispersion according to Clause 1, characterized in that the at least one biocidal compound is a bactericide, fungicide, and / or algaecide, preferably at least one isothiazolinone, particularly preferably selected from chloromethylisothiazolinone, methylisothiazolinone, benzisothiazolinone, octylisothiazolinone, methyltrimethyleneisothiazolinone, butylbenzisothiazolinone, dichlorooctylisothiazolinone, and / or mixtures of at least two of these, and even more preferably selected from 5-chloro-2-methylisothiazolinone / 2-methylisothiazolinone and / or mixtures thereof.

[0111] Clause 3. The aqueous polyurethane dispersion according to Clause 1 or Clause 2, characterized in that the at least one organic dialkyl dicarbonate is dimethyl dicarbonate, diethyl dicarbonate and / or a mixture thereof.

[0112] Clause 4. The aqueous polyurethane dispersion according to any one of Clauses 1 to 3, characterized in that, based on the total aqueous polyurethane dispersion, the at least one biocidal compound is present in an amount of 1 to 1000 mg / kg.

[0113] Clause 5. The aqueous polyurethane dispersion according to any one of Clauses 1 to 4, characterized in that, in each case, the at least one polyurethane is present in an amount of 5% to 64% by weight, preferably 30% to 60% by weight, particularly preferably 40% to 50% by weight, based on the total aqueous polyurethane dispersion.

[0114] Clause 6. The aqueous polyurethane dispersion according to any one of Clauses 1 to 5, characterized in that the aqueous polyurethane dispersion further comprises a component selected from adhesives, additives and auxiliaries, fillers, auxiliary agents, flow aids, reactive diluents, plasticizers, neutralizers, catalysts, auxiliary solvents, thickeners, additives, tackifiers and mixtures thereof.

[0115] Clause 7. The aqueous polyurethane dispersion according to any one of Clauses 1 to 6, characterized in that the at least one polyurethane has been or can be obtained by reacting the following synthetic components: (a) At least one diol and / or polyol component; (b) at least one diisocyanate and / or polyisocyanate component; (c) At least one component containing at least one hydrophilic group; (d) Optional mono-, di-, and / or triamino-functionalized and / or hydroxyamino-functionalized compounds; and (e) Other isocyanate reactive compounds may be selected; Components (a), (b), (c), (d), and (e) are different.

[0116] Clause 8. The aqueous polyurethane dispersion according to any one of Clauses 1 to 7, characterized in that, based on the total aqueous polyurethane dispersion, the at least one organic dialkyl dicarbonate is present in an amount of 0.001 g / kg to 100 g / kg, preferably 0.1 g / kg to 50 g / kg, particularly preferably 0.1 g / kg to 20 g / kg.

[0117] Clause 9. The aqueous polyurethane dispersion according to any one of Clauses 1 to 8, characterized in that, in each case, the water content of the aqueous polyurethane dispersion is from 36% to 95% by weight, preferably from 40% to 70% by weight, and particularly preferably from 50% to 60% by weight, based on the total aqueous polyurethane dispersion.

[0118] Clause 10. Use of at least one organic dialkyl dicarbonate in an aqueous polyurethane dispersion containing at least one polyurethane for reducing microorganisms, characterized in that the at least one organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate and / or mixtures of at least two of these.

[0119] Clause 11. The use according to Clause 10, characterized in that the aqueous polyurethane dispersion further contains at least one biocidal compound other than an organic dialkyl dicarbonate.

[0120] Clause 12. The use according to Clause 11, characterized in that the at least one biocidal compound is a bactericide, fungicide, and / or algaecide, preferably at least one isothiazolinone, particularly preferably selected from chloromethylisothiazolinone, methylisothiazolinone, benzisothiazolinone, octylisothiazolinone, methyltrimethyleneisothiazolinone, butylbenzisothiazolinone, dichlorooctylisothiazolinone, and / or mixtures of at least two of these, and even more preferably selected from 5-chloro-2-methylisothiazolinone / 2-methylisothiazolinone and / or mixtures thereof.

[0121] Clause 13. The use according to any one of Clauses 10 to 12, characterized in that the at least one organic dialkyl dicarbonate is dimethyl dicarbonate, diethyl dicarbonate and / or a mixture thereof.

[0122] Clause 14. The use according to any one of Clauses 11 to 13, characterized in that the at least one biocidal compound is present in an amount of 1 to 1000 mg / kg based on the total aqueous polyurethane dispersion.

[0123] Clause 15. The use according to any one of Clauses 10 to 14, characterized in that, in each case, the at least one polyurethane is present in an amount of 5% to 64% by weight, preferably 30% to 60% by weight, particularly preferably 40% to 50% by weight, based on the total aqueous polyurethane dispersion.

[0124] Clause 16. The use according to any one of Clauses 10 to 15, characterized in that the aqueous polyurethane dispersion further comprises a component selected from adhesives, additives and auxiliaries, fillers, auxiliaries, flow aids, reactive diluents, plasticizers, neutralizers, catalysts, auxiliary solvents, thickeners, additives, tackifiers and mixtures thereof.

[0125] Clause 17. The use according to any one of Clauses 10 to 16, characterized in that the at least one polyurethane has been or is available through the reaction of the following synthetic components: (a) At least one diol and / or polyol component; (b) at least one diisocyanate and / or polyisocyanate component; (c) At least one component containing at least one hydrophilic group; (d) Optional mono-, di-, and / or triamino-functionalized and / or hydroxyamino-functionalized compounds; and (e) Other isocyanate reactive compounds may be selected; Components (a), (b), (c), (d), and (e) are different.

[0126] Clause 18. The use according to any one of Clauses 10 to 17, characterized in that the at least one organic dialkyl dicarbonate is present in an amount of 0.001 g / kg to 100 g / kg, preferably 0.1 g / kg to 50 g / kg, particularly preferably 0.1 g / kg to 20 g / kg, based on the total aqueous polyurethane dispersion.

[0127] Clause 19. The use according to any one of Clauses 10 to 18, characterized in that, in each case, the water content of the aqueous polyurethane dispersion is from 36% to 95% by weight, preferably from 40% to 70% by weight, and particularly preferably from 50% to 60% by weight, based on the total aqueous polyurethane dispersion.

[0128] Clause 20. A method for producing an aqueous polyurethane dispersion containing a reduced amount of microorganisms, comprising at least the following steps: (A) Provide an aqueous polyurethane dispersion containing at least one type of polyurethane; (B) Treat the aqueous polyurethane dispersion from step (A) with at least one organic dialkyl dicarbonate, wherein the organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate and / or mixtures of at least two of these. To obtain an aqueous polyurethane dispersion containing a reduced amount of microorganisms.

[0129] Clause 21. The method according to Clause 20, characterized in that at least the following step (C) is performed before, after, or simultaneously with step (B): (C) Add at least one compound having biocidal activity, which is different from the at least one organic dialkyl dicarbonate, wherein step (C) is preferably performed before or simultaneously with step (B).

[0130] Clause 22. The method according to Clause 20 or Clause 21, characterized in that at least the following step (D) is performed after step (B) or step (C): (D) Production of articles, cosmetics, coatings; adhesive layers or adhesives from the aqueous polyurethane dispersion containing a reduced amount of microorganisms obtained in step (B) or step (C).

[0131] Clause 23. The method according to any one of Clauses 20 to 22, characterized in that step (B) is carried out at 1°C to 100°C, preferably at 5°C to 50°C, and particularly preferably at 10°C to 30°C.

[0132] Clause 24. The method according to any one of Clauses 21 to 23, characterized in that the at least one biocidal compound is a bactericide, fungicide, and / or algaecide, preferably at least one isothiazolinone, particularly preferably selected from chloromethylisothiazolinone, methylisothiazolinone, benzisothiazolinone, octylisothiazolinone, methyltrimethyleneisothiazolinone, butylbenzisothiazolinone, dichlorooctylisothiazolinone, and / or mixtures of at least two of these, and even more preferably selected from 5-chloro-2-methylisothiazolinone / 2-methylisothiazolinone and / or mixtures thereof.

[0133] Clause 25. The method according to any one of Clauses 21 to 24, characterized in that the at least one biocidal compound is present in an amount of 1 to 1000 mg / kg based on the total aqueous polyurethane dispersion.

[0134] Clause 26. The method according to any one of Clauses 20 to 25, characterized in that the at least one organic dialkyl dicarbonate is dimethyl dicarbonate, diethyl dicarbonate and / or a mixture thereof.

[0135] Clause 27. The method according to any one of Clauses 20 to 26, characterized in that, in each case, the at least one polyurethane is present in an amount of 5% to 64% by weight, preferably 30% to 60% by weight, particularly preferably 40% to 50% by weight, based on the total aqueous polyurethane dispersion.

[0136] Clause 28. The method according to any one of Clauses 20 to 27, characterized in that the aqueous polyurethane dispersion further contains a component selected from adhesives, additives and auxiliaries, fillers, auxiliaries, flow aids, reactive diluents, plasticizers, neutralizers, catalysts, auxiliary solvents, thickeners, additives, tackifiers and mixtures thereof.

[0137] Clause 29. The method according to any one of Clauses 20 to 28, characterized in that the at least one polyurethane has been or is available through the reaction of the following synthetic components: (a) At least one diol and / or polyol component; (b) at least one diisocyanate and / or polyisocyanate component; (c) At least one component containing at least one hydrophilic group; (d) Optional mono-, di-, and / or triamino-functionalized and / or hydroxyamino-functionalized compounds; and (e) Other isocyanate reactive compounds may be selected; Components (a), (b), (c), (d), and (e) are different.

[0138] Clause 30. The method according to any one of Clauses 20 to 29, characterized in that the at least one organic dialkyl dicarbonate is present in an amount of 0.001 g / kg to 100 g / kg, preferably 0.1 g / kg to 50 g / kg, particularly preferably 0.1 g / kg to 20 g / kg, based on the total aqueous polyurethane dispersion.

[0139] Clause 31. The method according to any one of Clauses 20 to 30, characterized in that, in each case, the water content of the aqueous polyurethane dispersion is from 36% to 95% by weight, preferably from 40% to 70% by weight, and particularly preferably from 50% to 60% by weight, based on the total aqueous polyurethane dispersion.

[0140] Clause 32. Aqueous polyurethane dispersions that can be obtained or acquired by any one of Clauses 10 to 31.

[0141] Clause 33. Articles, cosmetics, coatings, adhesive layers, coating formulations, adhesive formulations and / or cosmetic formulations containing at least one aqueous polyurethane dispersion as described in any one of Clauses 1 to 9 or containing an aqueous polyurethane dispersion containing a reduced amount of microorganisms as described in Clause 32.

[0142] The invention will now be illustrated with reference to working examples.

[0143] experiment Materials and sources The polyurethane dispersions used (Dispercoll® U 53, Dispercol® U 54) are sourced from Covestro Deutschland AG, Leverkusen, DE.

[0144] Unless otherwise stated, all other chemicals were obtained from Sigma-Aldrich Chemie GmbH, Taufkirchen, DE.

[0145] DMDC: Dimethyl dicarbonate DEDC: Diethyl dicarboxylate CMIT: Chloromethylisothiazolinone (5-chloro-2-methylisothiazolinone) MIT: Methylisothiazolinone (2-Methylisothiazolinone) Preventol® D7: 1.5% by weight of an aqueous solution of a mixture of 5-chloro-2-methylisothiazolinone / 2-methylisothiazolinone (CAS 55965-84-9), Lanxess Deutschland AG, DE.

[0146] Unless otherwise stated, all percentages are weight percentages (weight %).

[0147] Unless otherwise stated, all procedures and analytical measurements were performed at 23°C (room temperature).

[0148] method: Determination of germ status in polyurethane-polyurea-polyurethane dispersions: The determination of contamination or bacterial growth in polyurethane-polyurea-polyurethane dispersions was performed using a BacTrac 4300 from SY-LAB Geräte GmbH, Neupurkersdorf, Austria. For this purpose, 1 mL of the polyurethane-polyurea-polyurethane dispersion was poured into a BiMedia 001C measuring cell. The measuring cell was sealed with a nut and placed in the measuring unit of the BacTrac 4300, which was maintained at 30°C.

[0149] Microbial growth in polyurethane dispersion samples is accompanied by an increase in metabolites. The BacTrac 4300 measuring device uses the sample's AC resistance (impedance) as a measure for metabolite determination. A threshold (E) can be specified individually. If the threshold (E) is exceeded, the sample is considered non-sterile. For all measurements, the threshold (E) is set to a value of 8, and the maximum measurement duration is set to 72 hours. The sample temperature is maintained at 30°C during the measurement.

[0150] Description of the diptest system for determining bacterial load Based on DIN EN ISO 23321, use Mikrocount® combi impregnation slides ( Schülke & Mayr GmbH Norderstedt, DE To determine the total bacterial count, as well as the number of yeasts and molds, immerse the slide in the liquid material (polyurethane dispersion) to be tested, drain it, and incubate at 30°C for 3 days. Use the colony density (number of microorganisms per milliliter) in the chart to read the bacterial load, or determine the colony count if the colony density is low.

[0151] Example: Experiment 1 Pathogen analysis was performed on samples of the polyurethane dispersion Dispercoll® U53. Significant bacterial load was determined by smear test.

[0152] In each case, the sample was divided into four 100-gram portions of polyurethane dispersion. The sample was stirred in a container with a magnetic stir bar, and the following substances were added: a) None b) 0.1 g dimethyl dicarbonate c) 0.5 g dimethyl dicarbonate d) 1.0 g dimethyl dicarbonate.

[0153] Each mixture was stirred at room temperature for 5 hours. Pathogen analysis was performed one day later.

[0154] Table 1: Analysis Results of Experiment 1 **Analysis will be terminated after 72 hours; bacterial load will not be measured.** *A higher time value indicates lower pathogen growth during the test, and therefore a lower initial load in the sample.

[0155] The samples were then stored at room temperature and further pathogen assays were performed after 8 and 18 days.

[0156] Table 2: Pathogen assay results after 8 and 18 days **Analysis will be terminated after 72 hours; bacterial load will not be measured.** Evaluation: Adding as little as 0.1% by weight of DMDC (based on the mass of the polyurethane dispersion) achieved an initial reduction in bacterial count. However, under these conditions, pathogens began to multiply again during storage. Adding 0.5% or 1.0% by weight of DMDC resulted in sterile polyurethane dispersions even after 8 or 18 days of storage.

[0157] Experiment 2 Another sample of the Dispercoll® U53 polyurethane dispersion was analyzed for pathogens. The bacterial load was determined by a slide test.

[0158] In each case, the sample was divided into four 100g portions of polyurethane dispersion. The sample was stirred in a container with a magnetic stirrer, and the following substances were added: a) None b) 0.1 g dimethyl dicarbonate c) 0.5 g dimethyl dicarbonate d) 1.0 g dimethyl dicarbonate.

[0159] Stir each mixture at room temperature for 5 hours.

[0160] Table 3: Analysis Results of Experiment 2 **Analysis will be terminated after 72 hours; bacterial load will not be measured.** *A higher time value indicates lower pathogen growth during the test, and therefore a lower initial load in the sample.

[0161] Evaluation: The initial bacterial load of the polyurethane dispersion used was lower compared to the first batch of samples. The addition of as little as 0.1% DMDC achieved a reduction in microbial density to the point where colony-forming units were no longer detectable (sample b).

[0162] Experiment 3 Here, a sample of the contaminated polyurethane dispersion from Experiment 2 is used.

[0163] In each case, the sample was divided into four 100g portions of polyurethane dispersion. The sample was stirred in a container with a magnetic stirrer, and the following substances were added: a) None b) 0.1 g diethyl dicarbonate c) 0.5 g diethyl dicarbonate d) 1.0 g diethyl dicarbonate.

[0164] Stir each mixture at room temperature for 5 hours.

[0165] Table 4: Analysis Results of Experiment 3 *A higher time value indicates lower pathogen growth during the test, and therefore a lower initial load in the sample.

[0166] Evaluation: Diethyl dicarbonate also achieved a reduction in microbial content.

[0167] No significant changes were observed in the polyurethane dispersion during and after the addition of dimethyl dicarbonate and diethyl dicarbonate. After the addition of dimethyl dicarbonate, the average particle size (measured by Zetasizer, Malvern Panalytical Ltd, UK) and the viscosity of the polyurethane dispersion (Haake Viscotester iQ, Fisher Scientific GmbH, Schwerte, DE) did not change significantly, but only within the typical range for the analytical method. The polyurethane dispersion membrane was applied to a glass plate (doctor blade, 210 µm groove width) and dried at 50 °C for 1 hour, followed by drying at 120 °C for 1 hour. No visually detectable differences in membrane flowability, membrane quality, or color were observed after the addition of dimethyl dicarbonate compared to the membrane without additives.

[0168] Conclusion: The addition of dialkyl dicarbonate effectively reduces the bacterial count in polyurethane dispersions, in some cases below the detection limit. In experiments, dimethyl dicarbonate has been shown to reduce bacterial count more effectively than diethyl dicarbonate.

[0169] Experiment 4 Compatibility of organic dicarbonates with biocidal active ingredients.

[0170] Polyurethane dispersions are often mixed with isothiazolinones to achieve longer-lasting in-container corrosion protection, even when microorganisms enter, for example, after the container has been opened.

[0171] Dispercoll U 54 samples were mixed with Preventol D7, and different amounts of DMDC were added at room temperature. After one week, the content of biocidal active ingredients (CMIT and MIT) was determined by HPLC.

[0172] Table 5: Analysis results of Experiment 4 .

[0173] evaluate: No detectable decomposition of the active ingredients chloromethylisothiazolinone and methylisothiazolinone was observed by adding dimethyl dicarbonate.

[0174] Comparison Test 1 Compatibility of hydrogen peroxide with biocidal active ingredients To test whether polyurethane dispersions could also be treated similarly with hydrogen peroxide instead of dialkyl dicarbonate to reduce pathogen load without affecting other biocidal components, Dispercoll U 54 samples were mixed with Preventol D7, and different amounts of hydrogen peroxide (3% solution in water) were added at room temperature. After one week, the content of biocidal components was determined by HPLC.

[0175] Table 6: Analysis Results of Comparative Test 1 .

[0176] evaluate: Even with very small amounts of hydrogen peroxide, the active substances chloromethylisothiazolinone and methylisothiazolinone will decompose upon the addition of hydrogen peroxide solution. Therefore, it is impossible to treat with hydrogen peroxide while using chloromethylisothiazolinone or methylisothiazolinone for internal corrosion protection of the tank.

Claims

1. Aqueous polyurethane dispersions containing at least one polyurethane, at least one organic dialkyl dicarbonate and at least one compound having a biocidal effect which is different from the organic dialkyl dicarbonate, characterized in that The at least one organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or mixtures of at least two of these.

2. The use of at least one organic dialkyl dicarbonate in an aqueous polyurethane dispersion containing at least one polyurethane for reducing microorganisms, characterized in that... The at least one dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate, and / or mixtures of at least two of these.

3. The use according to claim 2, characterized in that... The aqueous polyurethane dispersion further contains at least one compound with biocidal activity, different from the organic dialkyl dicarbonate.

4. The use according to claim 3, characterized in that... The at least one biocidal compound is a bactericide, fungicide, and / or algaecide, preferably at least one isothiazolinone, particularly preferably selected from chloromethylisothiazolinone, methylisothiazolinone, benzisothiazolinone, octylisothiazolinone, methyltrimethyleneisothiazolinone, butylbenzisothiazolinone, dichlorooctylisothiazolinone, and / or mixtures of at least two of these, and even more preferably selected from 5-chloro-2-methylisothiazolinone / 2-methylisothiazolinone and / or mixtures thereof.

5. The use according to claim 3 or claim 4, characterized in that... Based on the total aqueous polyurethane dispersion, the at least one biocidal compound is present in an amount of 1 to 1000 mg / kg.

6. The use according to any one of claims 2 to 5, characterized in that... The at least one organic dialkyl dicarbonate is dimethyl dicarbonate, diethyl dicarbonate, and / or a mixture thereof.

7. The use according to any one of claims 2 to 6, characterized in that... In each case, the at least one polyurethane is present in an amount of 5% to 64% by weight, preferably 30% to 60% by weight, and particularly preferably 40% to 50% by weight, based on the total aqueous polyurethane dispersion.

8. The use according to any one of claims 2 to 7, characterized in that The at least one polyurethane has been or can be obtained through the reaction of the following synthetic components: (a) At least one diol and / or polyol component; (b) at least one diisocyanate and / or polyisocyanate component; (c) At least one component containing at least one hydrophilic group; (d) Optional mono-, di-, and / or triamino-functionalized and / or hydroxyamino-functionalized compounds; and (e) Other isocyanate reactive compounds may be selected; Components (a), (b), (c), (d), and (e) are different.

9. The use according to any one of claims 2 to 8, characterized in that... Based on the total aqueous polyurethane dispersion, the at least one organic dialkyl dicarbonate is present in an amount of 0.001 g / kg to 100 g / kg, preferably 0.1 g / kg to 50 g / kg, and particularly preferably 0.1 g / kg to 20 g / kg.

10. The use according to any one of claims 2 to 9, characterized in that... In each case, the water content of the aqueous polyurethane dispersion is from 36% to 95% by weight, preferably from 40% to 70% by weight, and particularly preferably from 50% to 60% by weight, based on the total aqueous polyurethane dispersion.

11. A method for producing an aqueous polyurethane dispersion containing a reduced amount of microorganisms, comprising at least the following steps: (A) Provide an aqueous polyurethane dispersion containing at least one type of polyurethane; (B) Treat the aqueous polyurethane dispersion from step (A) with at least one organic dialkyl dicarbonate, wherein the organic dialkyl dicarbonate is selected from dimethyl dicarbonate, diethyl dicarbonate, dipropyl dicarbonate, diisopropyl dicarbonate, methyl ethyl dicarbonate, ditert-butyl dicarbonate and / or mixtures of at least two of these. To obtain an aqueous polyurethane dispersion containing a reduced amount of microorganisms.

12. The method according to claim 11, characterized in that... Perform at least the following steps (C) before, after, or simultaneously with step (B): (C) Add at least one compound having biocidal activity, which is different from the at least one organic dialkyl dicarbonate, wherein step (C) is preferably performed before or simultaneously with step (B).

13. The method according to any one of claims 11 or 12, characterized in that... Perform at least the following step (D) after step (B) or step (C): (D) Production of articles, cosmetics, coatings; adhesive layers or adhesives from the aqueous polyurethane dispersion containing a reduced amount of microorganisms obtained in step (B) or step (C).

14. The method according to any one of claims 11 to 13, characterized in that... Step (B) is carried out at 1°C to 100°C, preferably at 5°C to 50°C, and particularly preferably at 10°C to 30°C.

15. The method according to any one of claims 12 to 14, characterized in that... The at least one biocidal compound is a bactericide, fungicide, and / or algaecide, preferably at least one isothiazolinone, particularly preferably selected from chloromethylisothiazolinone, methylisothiazolinone, benzisothiazolinone, octylisothiazolinone, methyltrimethyleneisothiazolinone, butylbenzisothiazolinone, dichlorooctylisothiazolinone, and / or mixtures of at least two of these, and even more preferably selected from 5-chloro-2-methylisothiazolinone / 2-methylisothiazolinone and / or mixtures thereof.

16. The method according to any one of claims 12 to 15, characterized in that... Based on the total aqueous polyurethane dispersion, the at least one biocidal compound is present in an amount of 1 to 1000 mg / kg.

17. The method according to any one of claims 11 to 16, characterized in that... The at least one organic dialkyl dicarbonate is dimethyl dicarbonate, diethyl dicarbonate, and / or a mixture thereof.

18. The method according to any one of claims 11 to 17, characterized in that... In each case, the at least one polyurethane is present in an amount of 5% to 64% by weight, preferably 30% to 60% by weight, and particularly preferably 40% to 50% by weight, based on the total aqueous polyurethane dispersion.

19. The method according to any one of claims 11 to 18, characterized in that... The at least one polyurethane has been or can be obtained through the reaction of the following synthetic components: (a) At least one diol and / or polyol component; (b) at least one diisocyanate and / or polyisocyanate component; (c) At least one component containing at least one hydrophilic group; (d) Optional mono-, di-, and / or triamino-functionalized and / or hydroxyamino-functionalized compounds; and (e) Other isocyanate reactive compounds may be selected; Components (a), (b), (c), (d), and (e) are different.

20. The method according to any one of claims 11 to 19, characterized in that... Based on the total aqueous polyurethane dispersion, the at least one organic dialkyl dicarbonate is present in an amount of 0.001 g / kg to 100 g / kg, preferably 0.1 g / kg to 50 g / kg, and particularly preferably 0.1 g / kg to 20 g / kg.

21. The method according to any one of claims 11 to 20, characterized in that... In each case, the water content of the aqueous polyurethane dispersion is from 36% to 95% by weight, preferably from 40% to 70% by weight, and particularly preferably from 50% to 60% by weight, based on the total aqueous polyurethane dispersion.

22. An aqueous polyurethane dispersion that can be obtained or acquired by the method according to any one of claims 11 to 21.

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