Two-component coating composition

Abstract

The present invention relates to a two-component coating composition, a process for producing the two-component coating composition, and the use of the two-component coating composition for coating metals, wood, plastics and glass, the two-component coating composition comprising: component (i), which is a composition comprising ia) at least one polyisocyanate, and ib) at least one gamma-lactone, which carries 1 or 2 radicals selected from C1-C6-alkyl, C1-C6-alkoxy and methylcarboxylic acid-C1-C4-alkyl, and component (ii), which comprises an aqueous dispersion of at least one hydroxyl-functional polymer P.

Description

describe

[0001] The present invention relates to a two-component coating composition comprising a polyisocyanate composition as component (i) and an aqueous dispersion of a hydroxyl-functionalized polymer P as component (ii), a method for producing the two-component coating composition, and the use of the two-component coating composition.

[0002] If emulsion polymers are used as binders for substrate coatings, one of the important requirements for such coatings is that they exhibit rapid property development, i.e., rapid hardening or rapid drying. Polyisocyanate components are added as crosslinking agents to compositions containing aqueous polymer dispersions and are extensively described in the literature. For ease of incorporation, conventional polyisocyanates are blended with solvents.

[0003] Hydrophilic modified polyisocyanates are often used as crosslinking agents. Such modifications can be advantageously distributed in waterborne paints. It has been found that coatings produced using this binder system have better gloss than acrylate dispersions crosslinked with unmodified hydrophobic polyisocyanates. On the other hand, coatings utilizing unmodified hydrophobic polyisocyanates exhibit good performance characteristics, but achieving a balance between better gloss and satisfactory drying time presents challenges.

[0004] EP 0 697 424 teaches the use of hydrophilically modified polyisocyanates in mixtures with ethylene carbonate or γ-butyrolactone as crosslinking agents to achieve aqueous polymer dispersions. Acrylic dispersions crosslinked in this manner still have much room for improvement in achieving drying times with better gloss.

[0005] WO 9403516 describes mixtures of polyols and polyisocyanates in water or water / solvent mixtures.

[0006] The fundamental problem is to provide alternative two-component coating compositions that offer faster drying and / or hardness development compared to existing systems, while still maintaining sufficient gloss.

[0007] These objectives have been surprisingly achieved by a two-component coating composition comprising: component (i), which is a composition comprising:

[0008] ia) at least one polyisocyanate, and

[0009] (ib) at least one γ-lactone having one or two groups selected from the group consisting of C1-C6 alkyl, C1-C6-alkoxy, and methylcarboxylic acid-C1-C4 alkyl groups.

[0010] And component (ii), which comprises an aqueous dispersion of at least one hydroxyl-functionalized polymer P.

[0011] These coating systems have been found to be non-hydrophilically modified polyisocyanates, meaning they are particularly well-suited to conventional polyisocyanates.

[0012] The present invention also relates to coated substrates that can be obtained using such two-component coating compositions.

[0013] Preferred embodiments can be found in the specification. Combinations of preferred embodiments are within the scope of this invention.

[0014] If the solids content of an aqueous dispersion is mentioned as a percentage by weight, it is based on the weight of the aqueous dispersion.

[0015] In the following text, the symbols “(meth)acrylic acid” or “(meth)acrylate” are generally intended to include not only the corresponding acrylic acid compound but also the corresponding methacrylic acid compound.

[0016] In the following text, the terms “group,” “substituent,” “base,” and “part” are used together, and each represents a covalently bonded substituent.

[0017] The two-component coating composition comprises a polyisocyanate composition as the first component (i) and an aqueous dispersion of a hydroxyl-functionalized polymer P as the second component (ii).

[0018] According to the present invention, component (i) comprises a substituted γ-lactone. A cyclic ester of 4-hydroxycarboxylic acid (R-CH(OH)-(CH2)2-COOH) is referred to as a γ-lactone (gamma-lactone).

[0019] These γ-lactones are substituted, preferably substituted with a group selected from C1-C6 alkyl, C1-C6-alkoxy, and methylcarboxylic acid-C1-C4 alkyl, preferably C1-C4 alkyl, especially methyl. γ-valerolactone and α-methyl-γ-butyrolactone are preferred, and γ-valerolactone is particularly preferred.

[0020] Preferred γ-lactones are bio-based, as determined using ASTM D6866-12.

[0021] The term "bio-based" means that the carbon is biologically derived and comes from biomaterials / renewable resources. The content of bio-carbon and the content in biomaterials are expressions representing the same value. Renewably sourced materials or biomaterials are organic materials in which the carbon originates from CO2 recently (on a human timescale) fixed from the atmosphere through photosynthesis. Biomaterials (100% naturally sourced carbon) 14 C / 12 C isotope ratio higher than 10 -12 Typically about 1.2 × 10 −12 Fossil materials do not contain 14C. In fact, isotopes 14 Carbon is formed in the atmosphere and subsequently integrated through photosynthesis, a process that takes at most a few decades. 14 The half-life of carbon is 5,730 years. Therefore, materials derived from photosynthesis, typically plants, must have the highest content of this isotope. 14 C. The determination of the content of biological materials or biocarbon can be performed according to standard ASTM D 6866-12.

[0022] Preferred γ-lactone 14 C / 12 The carbon isotope ratio is 0.5 × 10⁻⁶. -12 Up to 5×10 -12 0.5×10 is preferred. -12 Up to 3×10 -12 And more preferably 0.5×10 -12 Up to 2×10 -12 Preferably, the γ-lactone is derived from biomass, more preferably from starch or sugar, and most preferably from glucose, fructose, or cellulose. Preparation of γ-lactone from biomass is known, for example, from the following literature: ShantaDutta, Iris KMYu, Daniel CWTsang, Yun Hau Ng, Yong Sik Ok, James Sherwood, James H. Clark, “Green synthesis of gamma-verolactone through hydrogenation of biomass-derived levulinic acid using non-noble metal catalysts”, Chemical Engineering Journal 372 (2019), 992-1006.

[0023] Component (i)

[0024] The polyisocyanate component contains at least one polyisocyanate as component ia).

[0025] At least one polyisocyanate means a single polyisocyanate or a mixture of two or more polyisocyanates of different compositions, preferably a single polyisocyanate.

[0026] It should be understood that the expression "a polyisocyanate" also covers mixtures of polyisocyanates that differ only in their chain length and / or the arrangement of monomers within the polymer chain.

[0027] In a preferred embodiment, the polyisocyanate contains up to 0.01 molar equivalents of isocyanate groups selected from anionic groups and / or polyepoxide blocks.

[0028] In the following text, "anionic group" generally refers to an anion that contains not only an acid group but also the corresponding acid group, such as a sulfonyl group. A group that can be converted to an anionic group preferably becomes anionic when dispersed in water. To convert, for example, a sulfonyl group into an anionic group, inorganic and / or organic bases, such as sodium hydroxide, potassium hydroxide, potassium carbonate, sodium bicarbonate, ammonia, or primary, secondary, or especially tertiary amines, such as triethylamine or dimethylaminopropanol, can be used.

[0029] Polyepoxides are synonymous with polyalkylene glycols. A “polyepoxide block” is a chain having 2 to 80 epoxy units. The epoxy units can be ethylene oxide groups or mixtures of other epoxy units (such as propylene oxide groups).

[0030] Polyisocyanates that contain neither anionic groups nor polyethylene oxide blocks are particularly preferred.

[0031] In a preferred embodiment, the polyisocyanate is completely unmodified. This means it does not contain any hydrophilic components.

[0032] At least one polyisocyanate can be prepared by polymerization of monomeric aromatic, aliphatic and / or cycloaliphatic isocyanates, preferably aliphatic and / or cycloaliphatic (hereinafter referred to as (cyclo)aliphatic) isocyanates, and particularly preferably aliphatic isocyanates.

[0033] Aromatic isocyanates are isocyanates containing at least one aromatic ring system, i.e., pure aromatic compounds or arylepto-aromatic compounds. The former are isocyanates in which the isocyanate group is directly bonded to the aromatic ring system, while in the latter case, the isocyanate group is bonded to an alkylene group, but the compound still contains an aromatic ring system, such as in α,α,α',α'-tetramethylphenyldimethyl 1,3-diisocyanate (TMXDI).

[0034] Cyclic aliphatic isocyanates are those that contain at least one cyclic aliphatic ring system.

[0035] Aliphatic isocyanates are those that consist only of straight or branched carbon chains, i.e., acyclic compounds.

[0036] Monomeric aromatic, aliphatic, and / or cycloaliphatic isocyanates may be the same or different isocyanates in each case.

[0037] Monomeric aromatic, aliphatic, and / or cycloaliphatic isocyanates are preferably diisocyanates having exactly two isocyanate groups.

[0038] Higher isocyanates having an average of more than two isocyanate groups are also possible in principle. Examples of suitable compounds of this type are: triisocyanates, such as triisocyanate nonane, 2'-isocyanate ethyl 2,6-diisocyanate hexanoate, 2,4,6-triisocyanate toluene, triphenylmethane triisocyanate, or 2,4,4'-triisocyanate (diphenyl ether), or mixtures of diisocyanates, triisocyanates, and higher polyisocyanates.

[0039] Monomeric aromatic, aliphatic, and / or cyclic aliphatic isocyanates do not produce significant reaction products between their own isocyanate groups.

[0040] Monomeric aromatic, aliphatic, and / or cycloaliphatic isocyanates are preferably isocyanates having 4 to 20 carbon atoms. Examples of conventional diisocyanates are: aliphatic diisocyanates, such as tetramethylene diisocyanate, pentamethylene 1,5-diisocyanate (PDI), hexamethylene diisocyanate (1,6-diisocyanatohexane) (HDI), octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, and derivatives of lysine diisocyanate (e.g., methyl 2,6-diisocyanatohexanoate or...). Ethyl acetate), trimethylhexane diisocyanate or tetramethylhexane diisocyanate; cycloaliphatic diisocyanates, such as 1,4-, 1,3- or 1,2-diisocyanocyclohexane, 4,4'- or 2,4'-di(isocyanocyclohexyl)methane, 1-isocyano-3,3,5-trimethyl-5-(isocyanomethyl)cyclohexane (isophorone diisocyanate or IPDI), 1,3- or 1,4-bis(isocyanomethyl)cyclohexane Hexane or 2,4- or 2,6-diisocyanate-1-methylcyclohexane; and mixtures of 3- (or 4-), 8- (or 9-)bis(isocyanate-methyl)tricyclo[5.2.1.02.6]decane isomers; and aromatic diisocyanates, such as toluene 2,4- or 2,6-diisocyanate and mixtures of its isomers, meta- or terephthaloyl diisocyanate, 2,4'- or 4,4'-diisocyanate-diphenylmethane and its isomers. Mixtures of isomers, phenylene 1,3- or 1,4-diisocyanate, 1-chlorophenylene 2,4-diisocyanate, naphthylene 1,5-diisocyanate, diphenylene 4,4'-diisocyanate, 4,4'-diisocyanate-3,3'-dimethylbiphenyl, 3-methyldiphenylmethane 4,4'-diisocyanate, tetramethylphenyldimethyl diisocyanate, 1,4-diisocyanate-benzene or diphenyl ether 4,4'-diisocyanate.

[0041] Hexamethylene-1,6-diisocyanate, pentamethylene-1,5-diisocyanate, 1,3-bis(isocyanomethyl)cyclohexane, isophorone diisocyanate and 4,4'- or 2,4'-bis(isocyanocyclohexyl)methane are particularly preferred, and isophorone diisocyanate and hexamethylene-1,6-diisocyanate are especially preferred.

[0042] A mixture of the aforementioned isocyanates may also exist.

[0043] Isophorone diisocyanates are typically found as mixtures, i.e., mixtures of cis and trans isomers, typically in a ratio of about 60:40 to 90:10 (w / w), preferably 70:30 to 90:10.

[0044] Dicyclohexylmethane 4,4'-diisocyanate can also exist as a mixture of various cis and trans isomers.

[0045] As diisocyanates, diisocyanates obtained by phosgenation of the corresponding amines and those prepared without phosgene (i.e., by a phosgene-free method) may be used. For example, according to EP-A-126 299 (US 4 596 678), EP-A-126300 (US 4 596 679) and EP-A-355 443 (US 5 087 739), (cyclic)aliphatic diisocyanates, such as hexamethylene 1,6-diisocyanate (HDI), isomeric aliphatic diisocyanates having 6 carbon atoms in the alkylene group, 4,4'- or 2,4'-bis(isocyanocyclohexyl)methane, and 1-isocyano-3-isocyanomethyl-3,5,5-trimethylcyclohexane (isophorone diisocyanate or IPDI), can be prepared by reacting (cyclic)aliphatic diamines with, for example, urea and alcohols to form (cyclic)aliphatic dicarboxylates and thermally dissociating these into the corresponding diisocyanates and alcohols. This synthesis is typically carried out continuously in a cyclic process and optionally in the presence of N-unsubstituted carbamates, dialkyl carbonates, and other byproducts recycled from the reaction process. The diisocyanates obtained in this manner usually have very small or even immeasurable proportions of chlorination reaction products, which is advantageous, for example, in applications in the electronics industry, but is not limited thereto.

[0046] Advantageously, the total hydrolyzable chlorine content of the isocyanate used is less than 200 ppm, preferably less than 120 ppm, particularly preferably less than 80 ppm, very particularly preferably less than 50 ppm, especially less than 15 ppm, and especially less than 10 ppm. This can be measured, for example, according to ASTM method D4663-98. However, it is undoubtedly possible to use monomeric isocyanates with higher chlorine content, for example, up to 500 ppm.

[0047] It is also possible to use a mixture of monomeric isocyanates obtained by reacting a (cyclic) aliphatic diamine with, for example, a urea and an alcohol, dissociating the resulting (cyclic) aliphatic dicarboxylate, and combining it with a diisocyanate obtained by phosgenation of the corresponding amine.

[0048] At least one polyisocyanate that can be polymerized from monomeric isocyanates typically has the following properties:

[0049] The average NCO functionality of at least one polyisocyanate is typically at least 1.8 and can be up to 8, for example up to 6, preferably 2 to 5, and particularly preferably 2.4 to 4.

[0050] Unless otherwise stated, the content of isocyanate groups after polymerization, calculated as NCO = 42 g / mol, is typically 5% to 30% by weight based on polyisocyanate.

[0051] At least one polyisocyanate is preferably selected from the following compounds:

[0052] 1) One or more polyisocyanates having isocyanurate groups, derived from aromatic, aliphatic, and / or cycloaliphatic diisocyanates. Particularly preferred herein are the corresponding aliphatic and / or cycloaliphatic isocyanurates, and especially those based on hexamethylene diisocyanate and isophorone diisocyanate. The isocyanurates presented herein are particularly triisocyanoalkyl or triisocyanocycloalkyl isocyanurates, representing cyclic trimers of diisocyanates, or mixtures with their higher homologues having more than one isocyanurate ring. Isocyanoalkyl isocyanurates typically have an NCO content of 10% to 30% by weight, particularly 15% to 25% by weight, and an average NCO functionality of 2.6 to 8. Polyisocyanates having isocyanurate groups may also contain smaller amounts of urethane and / or urethane groups, preferably having a bound alcohol content of less than 2% by weight based on the polyisocyanate.

[0053] 2) One or more polyisocyanates having a ureidone group and an aromatic, aliphatic, and / or cycloaliphatic isocyanate group, preferably an aliphatic and / or cycloaliphatic isocyanate group, and particularly those derived from hexamethylene diisocyanate or isophorone diisocyanate. Urea diisocyanate is a cyclic dimer of diisocyanate.

[0054] Polyisocyanates with urea diketone groups are often obtained by blending with other polyisocyanates, particularly those mentioned in paragraph 1). Polyisocyanates with urea diketone groups typically have an NCO functionality of 2 to 3.

[0055] Therefore, diisocyanates can react under the following reaction conditions to form urea diketone groups and other polyisocyanates, or first form urea diketone groups and then convert them into other polyisocyanates, or diisocyanates first react to form other polyisocyanates and then convert them into products containing urea diketone groups.

[0056] 3) One or more polyisocyanates having biuret groups and aromatic, cycloaliphatic or aliphatic bonds, preferably cycloaliphatic or aliphatic bonds, of isocyanate groups, particularly tris(6-isocyanatohexyl) biuret or mixtures thereof with its higher homologues. These polyisocyanates having biuret groups typically have an NCO content of 18% to 24% by weight and an average NCO functionality of 2.8 to 6.

[0057] Polyisocyanates having urea diketone groups are often obtained by blending with other polyisocyanates, particularly urea, and those mentioned in paragraphs 1 and 2.

[0058] 4) One or more polyisocyanates having urethane and / or urea carbamate groups and aromatic, aliphatic, or cycloaliphatic isocyanate groups, preferably aliphatic or cycloaliphatic, obtained, for example, by reacting excess diisocyanate (e.g., hexamethylene diisocyanate or isophorone diisocyanate) with a monohydric or polyhydric alcohol. These polyisocyanates having urethane and / or urea carbamate groups typically have an NCO content of 12% to 24% by weight and an average NCO functionality of 2.0 to 4.5.

[0059] Such polyisocyanates having urethane and / or urea carbamate groups can be prepared in the absence of a catalyst or preferably in the presence of a catalyst, such as ammonium carboxylate or ammonium hydroxide or urea carbamate esterification catalyst, such as bismuth compounds, cobalt compounds, cesium compounds, Zn(II) or Zr(IV) compounds, in each case prepared in the presence of a monohydric alcohol, dihydric alcohol or polyhydric alcohol, preferably a monohydric alcohol.

[0060] Polyisocyanates having urethane and / or urethane groups are often present in mixed forms with the polyisocyanates mentioned in paragraph 1).

[0061] 6) One or more polyisocyanates (commonly referred to as asymmetric isocyanurates) containing an iminooxadiazine dione group, preferably derived from hexamethylene diisocyanate, pentamethylene diisocyanate, or isophorone diisocyanate, with hexamethylene diisocyanate being the most preferred. Such polyisocyanates containing an iminooxadiazine dione group can be prepared, for example, from diisocyanates using a specific catalyst.

[0062] Polyisocyanates containing iminooxadiazine dione groups are often obtained by blending with other polyisocyanates, particularly those mentioned in paragraphs 1 and 2.

[0063] 9) One or more hyperbranched polyisocyanates, for example, known from DE-A 10013186 or DE-A 10013187.

[0064] 10) In the above items, preferably, the polyisocyanates 1)-9) described in 1), 2), 3), 4) and 6) can be converted after their preparation into polyisocyanates having biuret groups or urethane / urethane groups and aromatic, cycloaliphatic or aliphatic, preferably (cyclo)aliphatic, isocyanate groups. The formation of biuret groups is affected, for example, by the addition of water or by reaction with amines. The formation of urethane and / or urethane groups is affected by reaction with monohydric alcohols, dihydric alcohols or polyhydric alcohols (preferably monohydric alcohols) optionally in the presence of a suitable catalyst. These polyisocyanates having biuret or urethane / urethane groups typically have an NCO content of 10% to 25% by weight and an average NCO functionality of 3 to 8.

[0065] 11) Polyisocyanates, which include not only the groups described in 1) to 10), but also groups formed in the form of adding molecules having NCO-reactive groups and groups that can be crosslinked by UV or photochemical radiation to the isocyanate groups of the above-described molecules. These molecules are, for example, hydroxyalkyl (meth)acrylates and other hydroxyvinyl compounds.

[0066] The diisocyanates or polyisocyanates described above may also exist, at least partially, in a closed form.

[0067] The class of compounds used for blocking is described in DA Wicks, ZW Wicks, Progress in Organic Coatings, 36, 148-172 (1999), 41, 1-83 (2001) and 43, 131-140 (2001).

[0068] Examples of compound classes used for blocking are phenols, imidazoles, triazoles, pyrazoles, oximes, N-hydroxyimides, hydroxybenzoates, secondary amines, lactams, CH-acidic cyclic ketones, malonates, or alkyl acetoacetates.

[0069] Advantageously, at least one polyisocyanate is selected from the group consisting of polyisocyanurate and polyisocyanates containing iminooxadiazine dione groups, biuret, urethane and urethane, preferably from the group consisting of isocyanurate, isocyanate containing iminooxadiazine dione groups, urethane and urethane, wherein polyisocyanates containing iminooxadiazine dione groups and / or isocyanurate groups are particularly preferred.

[0070] At least one polyisocyanate is particularly preferred to be based on aliphatic and / or cycloaliphatic diisocyanates, and very particularly preferred to be based on hexamethylene 1,6-diisocyanate, pentamethylene 1,6-diisocyanate and / or isophorone diisocyanate.

[0071] Furthermore, it is particularly preferred that at least one polyisocyanate is a mixture of polyisocyanates, and very particularly preferred are polyisocyanates based on hexamethylene 1,6-diisocyanate and polyisocyanates based on isophorone diisocyanate.

[0072] In a particularly preferred embodiment, at least one polyisocyanate is a mixture comprising low-viscosity polyisocyanates, preferably low-viscosity polyisocyanates comprising isocyanurate groups with a viscosity of 600 mPa*s to 3500 mPa*s, particularly below 1500 mPa*s, low-viscosity urethanes and / or urethanes with a viscosity of 200 mPa*s to 1600 mPa*s, particularly 500 mPa*s to 1500 mPa*s, and / or polyisocyanates comprising iminooxadiazine dione groups with a viscosity of 400 mPa*s to 2000 mPa*s, particularly 500 mPa*s to 1500 mPa*s.

[0073] Unless otherwise stated, the viscosity values ​​reported in this document are based on DIN EN ISO 3219 / A.3 (October 1994) at 23°C using a cone-plate system at 1000 s. -1 The shear rate was determined.

[0074] At least one polyisocyanate can be prepared, for example, by methods known to those skilled in the art.

[0075] A method for preparing at least one polyisocyanate may be carried out as described in WO 2008 / 68198, particularly on page 20, line 21 to page 27, line 15, which is incorporated herein by reference.

[0076] The reaction may be terminated, for example, as described on page 31, line 19 to page 31, line 31, and the post-processing may be carried out as described on page 31, line 33 to page 32, line 40, which in each case are incorporated herein by reference.

[0077] As an alternative, the reaction may also be terminated as described in WO 2005 / 087828 on page 11, line 12 to page 12, line 5, which is incorporated herein by reference.

[0078] In the preparation of at least one polyisocyanate, thermally stable catalysts and thermally unstable catalysts may be used.

[0079] If a thermally unstable catalyst is used in the preparation of at least one polyisocyanate, the reaction can also be terminated by heating the reaction mixture to a temperature above 80°C, preferably at least 100°C, and particularly preferably at least 120°C. The heating of the reaction mixture necessary for the separation of unreacted isocyanate by distillation in post-treatment is usually sufficient to achieve this.

[0080] In both the case of thermally stable and thermally unstable catalysts, the reaction can be terminated at a lower temperature by adding a deactivating agent. Suitable deactivating agents include, for example, hydrogen chloride, phosphoric acid, organophosphates (such as dibutyl phosphate or diethylhexyl phosphate), carbamates (such as hydroxyalkyl carbamate), or organic carboxylic acids.

[0081] These compounds are added either in pure form or after being diluted to the appropriate concentration required to terminate the reaction.

[0082] Diisocyanates, triisocyanates, and higher polyisocyanates can be obtained, for example, by phosgenation of the corresponding aniline / formaldehyde condensate, and can be polyphenyl polyisocyanates with methylene bridges.

[0083] This composition is obtained by assembling the components. For example, this is accomplished by a mixing device such as a mechanical stirrer.

[0084] Component (i) of the two-component coating composition is obtained by combining polyisocyanate and γ-lactone. This can be accomplished by simply mixing the two components with a mechanical stirrer.

[0085] Preferably, component (i) comprises 5% to 50% by weight of γ-lactone based on the sum of polyisocyanate (ia) and γ-lactone (ib).

[0086] It has been found that γ-lactones, as components of the 2K composition according to the invention, contribute to the favorable properties of the surface coating. Undoubtedly, other diluents may be added to some extent, provided these properties are not degraded. Known diluents are, for example, but not limited to: methoxypropyl acetate, dipropylene glycol dimethyl ether, dipropylene glycol monomethyl ether acetate, butyl ethylene glycol acetate, propylene carbonate, TME 1,1,2,2-tetramethoxyethane, dioxane, dioxolane, ethyl acetate, butyl acetate, ethylene glycol monoethyl or ethyl ether acetate, 1-methoxypropyl 2-acetate, 2-butanone, 4-methyl-2-pentanone, cyclohexane, toluene, propylene glycol diacetate, diethylene glycol dimethyl ether, diethylene glycol ethyl or butyl ether acetate, N-methylpyrrolidone, N-ethylpyrrolidone, N-methylcaprolactam, and THF.

[0087] Preferably, component (i) comprises:

[0088] At least one polyisocyanate, 35%-90% by weight, preferably 60%-75% by weight.

[0089] 5%-65% by weight, preferably 20%-40% by weight of γ-lactone

[0090] 0%-25% by weight, preferably 0%-5% by weight, of a non-γ-lactone diluent

[0091] 0%-3% by weight, preferably 0%-0.5% by weight of additives

[0092] The sum of the weight percentages is 100% by weight.

[0093] Common additives used for polyisocyanates are silane additives and / or catalysts for the formation of urethanes.

[0094] Component (ii)

[0095] The hydroxyl-functionalized polymer P may be, for example: polyacrylate polyol, polyester polyol, polyether polyol, polyurethane polyol; polyurea polyol; polyester polyacrylate polyol; polyester polyurethane polyol; polyurethane polyacrylate polyol, polyurethane-modified alkyd resin; fatty acid-modified polyester polyurethane polyol, copolymer with allyl ether, graft polymer from, for example, the group of materials with different glass transition temperatures, and mixtures of the aforementioned polymers.

[0096] The polymers dispersed in the polymer dispersion are particularly preferred to be polyacrylate polyols and polyester alcohols, especially polyacrylate polyols.

[0097] According to DIN 53240-2 (potential determination), the preferred OH value is 40 mg KOH / g solid resin to 350 mg KOH / g solid resin for polyester, preferably 80 mg KOH / g solid resin to 180 mg KOH / g solid resin; and 15 mg KOH / g solid resin to 250 mg KOH / g solid resin for polyacrylate alcohol, preferably 80 mg KOH / g to 160 mg KOH / g.

[0098] In addition, according to DIN EN ISO 3682 (potential determination), the acid value of the polymer dispersed in the polymer dispersion can be up to 200 mg KOH / g, preferably up to 150 mg KOH / g, and particularly preferably up to 100 mg KOH / g.

[0099] Hydroxyl-functionalized polymers P can be, for example, polyester polyols obtained by condensation of polycarboxylic acids, more particularly dicarboxylic acids, with polyols, more particularly diols. To ensure that the polyester polyol has a suitable degree of functionality for polymerization, triols, tetraols, and tricarboxylic acids are also used in part.

[0100] Polyester polyols are known, for example, from Ullmann's Enzyklopädie der technischen Chemie, 4th edition, Vol. 19, pp. 62-65. Preferred are polyester polyols obtained by reacting a diol with a dicarboxylic acid. Instead of free polycarboxylic acids, polyester polyols may also be prepared using the corresponding polycarboxylic anhydrides or corresponding polycarboxylic esters of lower alcohols, or mixtures thereof. The polycarboxylic acids may be aliphatic, cycloaliphatic, aromatic, or heterocyclic, and may optionally be substituted with, for example, halogen atoms and / or unsaturated.

[0101] In the following text, the term "polyacrylate polyol" refers to copolymers of hydroxy-functional acrylic and / or methacrylic acid monomers combined with other comonomers.

[0102] The polyacrylate polyol preferably has a molecular weight Mn of at least 500 g / mol, particularly preferably at least 1200 g / mol. The molecular weight Mn can be unlimited in principle, and is preferably up to 50,000 g / mol, particularly preferably up to 20,000 g / mol, very particularly preferably up to 10,000 g / mol, and especially up to 5,000 g / mol.

[0103] Number-average molecular weight was determined using appropriate calibration compounds via gel permeation chromatography, a method familiar to those skilled in the art.

[0104] Polyacrylate polyols can be secondary dispersions, which are polymers produced by solution polymerization and then dispersed in water.

[0105] The preparation of polymers dispersed in polymer dispersions is preferably carried out by emulsion polymerization.

[0106] Preferably, hydroxyl-functionalized monomers are blended and copolymerized with other polymerizable monomers.

[0107] Hydroxyl-functionalized monomers can be used simultaneously in copolymerization, and the amount used is such that the hydroxyl value of the copolymer obtained is typically 0.5% to 8% by weight, preferably 1% to 5% by weight, corresponding to a hydroxyl group content of 0.5% to 8% by weight.

[0108] Preferably, the hydroxyl-functional polymer P is prepared by polymerization of at least one hydroxyl-functional (meth)acrylate (Ma) and at least one monomer (Mb) selected from the group consisting of: alkyl (meth)acrylates, vinyl aromatic compounds, α,β-unsaturated carboxylic acids and other monomers.

[0109] The preferred hydroxyl value of at least one hydroxyl-functionalized polymer (solid) is 15 mg KOH / g to 250 mg KOH / g, preferably 40 mg KOH / g polymer to 120 mg KOH / g polymer.

[0110] Examples of alkyl (meth)acrylates include (meth)acrylate C1-C 20 Alkyl esters, vinyl aromatic compounds are those having up to 20 carbon atoms, α,β-unsaturated carboxylic acids also include their anhydrides, and other monomers are, for example, vinyl esters of carboxylic acids containing up to 20 carbon atoms, olefinic unsaturated nitriles, vinyl ethers of alcohols containing 1 to 10 carbon atoms, and less preferably aliphatic hydrocarbons having 2 to 8 carbon atoms and 1 or 2 double bonds.

[0111] Examples of alkyl methacrylates include: methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, n-pentyl methacrylate, isopentyl methacrylate, 2-methylbutyl methacrylate, pentanol methacrylate, n-hexyl methacrylate, 2-ethylbutyl methacrylate, pentanol methacrylate, n-ethylhexyl methacrylate, n-heptyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, 2-propylheptyl methacrylate, n-decyl methacrylate, undecyl methacrylate, and / or n-dodecyl methacrylate.

[0112] Preferred alkyl (meth)acrylates are those having C1-C2. 10Those with alkyl groups are particularly preferred, including methyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate, n-butyl methacrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate and / or 3-propylheptyl acrylate.

[0113] In particular, mixtures of (meth)acrylate alkyl esters are also suitable.

[0114] Vinyl esters of carboxylic acids having 1 to 20 carbon atoms are, for example, vinyl laurate, vinyl stearate, vinyl propionate, and vinyl acetate.

[0115] α,β-unsaturated carboxylic acids and their anhydrides may be, for example, acrylic acid, methacrylic acid, fumaric acid, crotonic acid, itaconic acid, maleic acid or maleic anhydride, with acrylic acid being preferred.

[0116] As hydroxy esters of (meth)acrylate, references may be made to monoesters of α,β-unsaturated acrylic acid and / or methacrylic acid (hereinafter referred to as "(meth)acrylate") with diols or polyols, preferably having 2 to 20 carbon atoms and at least two hydroxyl groups, such as: ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,1-dimethyl-1,2-ethylenediol, dipropylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, tripropylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentanediol, hydroxypentacolate of neopentanediol, 2-ethyl-1,3-propanediol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,6-hexanediol, 2-methyl-1,5-pentanediol, 2-ethyl-1,4-butanediol, 2-ethyl-1,3-hexanediol. Diol, 2,4-diethyloctane-1,3-diol, 2,2-bis(4-hydroxycyclohexyl)propane, 1,1-, 1,2-, 1,3- and 1,4-bis(hydroxymethyl)cyclohexane, 1,2-, 1,3- or 1,4-cyclohexanediol, glycerol, trimethylolethane, trimethylolpropane, trimethylolbutane, pentaerythritol, bis(trimethylolpropane), dipentaerythritol, sorbitol, mannitol, diglycerol, Threonitol, erythritol, arbutinol (ribitol), arabitol (lythritol), xylitol, galactitol, maltitol, isomaltitol, polyTHF with a molecular weight in the range of 162 to 4500 (preferably 250 to 2000), poly-1,3-propanediol or polypropylene glycol with a molecular weight in the range of 134 to 2000, or polyethylene glycol with a molecular weight in the range of 238 to 2000.

[0117] Preferred materials include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2- or 3-hydroxypropyl acrylate, 1,4-butanediol monoacrylate or 3-(acryloyloxy)-2-hydroxypropyl acrylate, with 2-hydroxyethyl acrylate and / or 2-hydroxyethyl methacrylate being particularly preferred.

[0118] Possible vinyl aromatic compounds are, for example, vinyltoluene, α-butylstyrene, α-methylstyrene, 4-n-butylstyrene, 4-n-decylstyrene, with styrene being preferred.

[0119] Examples of nitrile are acrylonitrile and methacrylonitrile.

[0120] Suitable vinyl ethers are, for example, vinyl methyl ether, vinyl isobutyl ether, vinyl hexyl ether, and vinyl octyl ether.

[0121] As non-aromatic hydrocarbons having 2 to 8 carbon atoms and one or two olefinic double bonds, butadiene, isoprene, ethylene, propylene, and isobutene can be mentioned.

[0122] N-vinylformamide, N-vinylpyrrolidone, and N-vinylcaprolactam, as well as olefinic unsaturated acids, particularly carboxylic acids, anhydrides, or amides, and vinylimidazoles, may also be used. Comonomers with epoxy groups (such as acrylic acid or glycidyl methacrylate) or monomers such as N-methoxymethacrylamide or N-methoxymethacrylamide may also be used in small amounts concurrently.

[0123] Preferably, it is an ester of acrylic acid or methacrylic acid having 1 to 18, preferably 1 to 8, carbon atoms in the alcohol group, such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, n-octadecyl acrylate, methacrylates corresponding to these acrylates, styrene, alkyl-substituted styrene, acrylonitrile, methacrylonitrile, vinyl acetate or vinyl stearate, or any mixture of such monomers.

[0124] In the copolymerization of (meth)acrylates with hydroxyl groups, the hydroxyl-functionalized monomer is used as a mixture with other polymerizable monomers, preferably free radical polymerizable monomers, the latter preferably being more than 50% by weight of (meth)acrylate C1-C 20 Alkyl esters, preferably C1 to C4 alkyl esters of (meth)acrylic acid, (meth)acrylic acid, vinyl aromatic compounds having up to 20 carbon atoms, vinyl esters of carboxylic acids containing up to 20 carbon atoms, vinyl halides, non-aromatic hydrocarbons having 4 to 8 carbon atoms and 1 or 2 double bonds, unsaturated nitriles, and mixtures thereof. Particularly preferred polymers are those consisting of more than 60% by weight (meth)acrylic acid C1-C4 alkyl esters, excluding monomers with hydroxyl groups, based on the total amount of monomers.10 Those consisting of alkyl esters, styrene and their derivatives, or mixtures thereof.

[0125] Preferably, the copolymerization of at least one hydroxyl-functionalized poly(meth)acrylate is a free radical-initiated aqueous emulsion polymerization. The implementation of free radical-initiated aqueous emulsion polymerization is a subject described in many previous studies and is therefore well known to those skilled in the art [in this regard, see: Emulsion Polymerization, in Encyclopedia of Polymer Science and Engineering, Vol. 8, p. 659 and thereafter (1987); DC Blackley, in High Polymer Latices, Vol. 1, p. 35 and thereafter (1966); H. Warson, The Applications of Synthetic Resin Emulsions, Chapter 5, p. 246 and thereafter (1972); D. Diederich, Chemiein unserer Zeit, 24, pp. 135-142 (1990); Emulsion Polymerization, Interscience Publishers, New York (1965); DE-A 40 03 422, and Dispersionen synthetischer Hochpolymerer, F. Hölscher, Springer-Verlag, Berlin]. (1969)]. The conventional form of free radical-initiated aqueous emulsion polymerization involves dispersing monomers in an aqueous medium (usually with the aid of dispersants such as emulsifiers and / or protective colloids) and polymerizing them using at least one water-soluble free radical polymerization initiator. In the obtained aqueous polymer dispersion, the residual level of unreacted monomers is often reduced by chemical and / or physical methods also known to those skilled in the art [see, for example, EP-A 771328, DE-A 19624299, DE-A 19621027, DE-A 19741184, DE-A19741187, DE-A 19805122, DE-A 19828183, DE-A 19839199, and DE-A 19840586 and 19847115], by adjusting the polymer solids content to the desired value through dilution or concentration, or by adding other conventional additives, such as foaming or viscosity modifiers, to the aqueous polymer dispersion.

[0126] Free radical-initiated aqueous emulsion polymerization can be carried out in a multi-stage polymerization process. A multi-stage polymerization process refers to the sequential polymerization of a mixture of two or more independent monomers in two or more independent operations.

[0127] Free radical-initiated aqueous emulsion polymerization is typically carried out in the presence of a free radical polymerization initiator (free radical initiator) at a concentration of 0.1% to 5% by weight, preferably 0.1% to 4% by weight, and more particularly 0.1% to 3% by weight, based on the total monomer content in each case. The anticipated free radical initiators include all those capable of initiating free radical aqueous emulsion polymerization. These can in principle be of two classes: peroxides and azo compounds. It should be understood that redox initiator systems are also considered. As peroxides, inorganic peroxides, such as hydrogen peroxide or persulfate, monoalkali metal salts or dialkali metal salts or ammonium salts such as persulfate, such as their monosodium and disodium, monopotassium and dipotassium or ammonium salts; or organic peroxides, such as alkyl hydroperoxides, examples being tert-butyl hydroperoxide, p-menthol hydroperoxide or cumyl hydroperoxide, and dialkyl or diaryl peroxides, such as di-tert-butyl or dicumyl peroxide. As azo compounds, 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylpentanonitrile), and 2,2'-azobis(amidinylpropyl) dihydrochloride (AIBA, corresponding to V-50 from Wako Chemicals) are generally used. It should be understood that systems referred to as redox initiator systems can also be used as free radical initiators. The oxidants considered for use in redox initiator systems are essentially the peroxides identified above. As corresponding reducing agents, low-oxidation-state sulfur compounds may be used, such as alkali metal salts of sulfites (e.g., potassium sulfite and / or sodium sulfite), alkali metal salts of bisulfites (e.g., potassium bisulfite and / or sodium bisulfite), alkali metal salts of metabisulfites (e.g., potassium metabisulfite and / or sodium metabisulfite), formaldehyde sulfoxides (e.g., potassium formaldehyde sulfoxide and / or sodium formaldehyde sulfoxide), alkali metal salts of aliphatic sulfinic acids (especially potassium and / or sodium salts), and alkali metal hydrosulfides (e.g., potassium hydrosulfide and / or sodium hydrosulfide); polyvalent metal salts, such as ferric(II) sulfate, ammonium ferric(II) sulfate, ferric(II) phosphate; olefinic alcohols, such as dihydroxymaleic acid, benzoin, and / or ascorbic acid; and reducing sugars, such as sorbitol, glucose, fructose, and / or dihydroxyacetone.

[0128] Initiation of a polymerization reaction refers to the start of the polymerization reaction of monomers present in the polymerization vessel after the formation of free radicals with a free radical initiator. This initiation can be achieved by adding a free radical initiator to an aqueous polymerization mixture in the polymerization vessel under polymerization conditions. However, another possibility is to add part or all of the free radical initiator to an aqueous polymerization mixture containing initially introduced monomers in the polymerization vessel under conditions unsuitable for initiating the polymerization reaction (e.g., low temperature), and then establish polymerization conditions in the aqueous polymerization mixture thereafter. The polymerization conditions here are typically those temperatures and pressures at which free radical-initiated aqueous emulsion polymerization proceeds at a sufficient polymerization rate. They are particularly dependent on the free radical initiator used. Advantageously, the nature and amount of the free radical initiator, the polymerization temperature, and the polymerization pressure are selected such that the half-life of the free radical initiator is <3 hours, and particularly advantageously <1 hour, while always having sufficient initiating free radicals available to initiate and sustain the polymerization reaction.

[0129] The reaction temperatures considered for free radical-initiated aqueous emulsion polymerization span the entire range from 0°C to 170°C. Temperatures used here are typically from 50°C to 120°C, preferably from 60°C to 110°C, and particularly preferably from 60°C to 100°C. Free radical-initiated aqueous emulsion polymerization can be carried out at pressures below, equal to, or above 1 atm [1.013 bar (absolute value), atmospheric pressure], and therefore polymerization temperatures can exceed 100°C and may reach as high as 170°C. In the presence of low-boiling-point monomers, emulsion polymerization is preferably carried out at elevated pressures. In this case, pressures can be 1.2 bar, 1.5 bar, 2 bar, 5 bar, 10 bar, or 15 bar (absolute value) or even higher. If emulsion polymerization is carried out at pressures below atmospheric pressure, pressures of 950 mbar, often 900 mbar, and frequently 850 mbar (absolute value) are set. Free radical aqueous emulsion polymerization is advantageously carried out at 1 atm in the absence of oxygen, and more particularly in an inert gas atmosphere, such as nitrogen or argon.

[0130] According to the present invention, the entirety of the free radical initiator may be included in the initial charge in the aqueous reaction medium prior to initiating the polymerization reaction. However, another possibility is that, optionally, only a portion of the free radical initiator may be included in the initial charge in the aqueous reaction medium prior to initiating the polymerization reaction; then, during the free radical-initiated emulsion polymerization, all or any remaining portion may be added continuously or discontinuously according to the initiator consumption rate under the polymerization conditions. In a preferred embodiment, the entirety of the free radical initiator is included in the initial charge in the aqueous reaction medium prior to initiating the polymerization reaction.

[0131] Generally, the total amount of free radical initiator is ≥ 0.05% by weight and ≤ 5% by weight based on the total monomer amount in each case, preferably ≥ 0.1% by weight and ≤ 3% by weight, and more preferably ≥ 0.1% by weight and ≤ 1.5% by weight.

[0132] To determine the weight-average molecular weight, optionally, compounds that induce free radical chain transfer (chain transfer agents) are used. In this case, primarily aliphatic and / or aryliphatic halogen compounds are employed, such as n-butyl chloride, n-butyl bromide, n-butyl iodide, dichloromethane, dichloroethane, chloroform, bromoform, bromotrichloromethane, dibromodichloromethane, carbon tetrachloride, carbon tetrabromide, benzyl chloride, benzyl bromide; organothioides, such as primary, secondary, or tertiary aliphatic thiols, such as ethanethiol, n-propanethiol, 2-propanethiol, n-butanethiol, 2-butanethiol, 2-methyl-2-propanethiol, n-pentanethiol, 2-pentanethiol, 3-pentanethiol, 2-methyl-2-butanethiol, 3-methyl-2-butanethiol, n-hexanethiol, 2-hexanethiol, 3-hexanethiol, 2-methyl-2-pentanethiol, 3-methyl-2-pentanethiol, 4- 2-Methyl-2-pentanethiol, 2-methyl-3-pentanethiol, 3-methyl-3-pentanethiol, 2-ethylbutanethiol, 2-ethyl-2-butanethiol, n-heptanethiol and its isomers, n-octanethiol and its isomers, n-nonanethiol and its isomers, n-decanethiol and its isomers, n-undecanethiol and its isomers, n-dodecanethiol and its isomers, n-tridecanethiol and its isomers; substituted thiols, such as 2-hydroxyethylthiol; aromatic thiols, such as benzenethiol, o-, m-, or p-methylbenzenethiol; mercaptoalkanoic acids and their derivatives, such as 6-methylheptyl 3-mercaptopropionate or 2-ethylhexyl 2-mercaptoacetic acid, and Polymer All other sulfur compounds described in Handbook 3rd Edition, 1989, J. Brandrup and E. Himmergut, John Wiley & Sons, Part II, pp. 133–141; and aliphatic and / or aromatic aldehydes, such as acetaldehyde, propionaldehyde, and / or benzaldehyde; unsaturated fatty acids, such as oleic acid; dienes with non-conjugated double bonds, such as divinylmethane or vinylcyclohexane; or hydrocarbons with readily abstractable hydrogen atoms, such as toluene. Another possibility is the use of a mixture of the aforementioned chain transfer agents that do not interfere with each other.

[0133] Prior to initiating the polymerization reaction, the entire chain transfer agent may be included in the initial charge in the aqueous reaction medium. However, another possibility is that, optionally, only a portion of the chain transfer agent may be included in the initial charge in the aqueous reaction medium before initiating the polymerization reaction; then, during the free radical-initiated emulsion polymerization, all or any remaining portion may be added continuously or discontinuously, as needed and as required, under the polymerization conditions. Importantly, however, is that the properties and amount of the chain transfer agent are selected to obtain the specified weight-average molecular weight.

[0134] Generally, the amount of chain transfer agent is from 0% to 20% by weight based on the total amount of monomers in each case, preferably from 0.05% to 10% by weight, and more preferably from 0.1% to 2% by weight.

[0135] Emulsion polymerization can also optionally be carried out in the presence of a dispersing agent that keeps both monomer droplets and polymer particles dispersed in the aqueous phase, and thus ensures the stability of the aqueous dispersion produced by the dispersed polymer. Compounds considered as such dispersing agents include emulsifiers and protective colloids commonly used to carry out free radical aqueous emulsion polymerization.

[0136] Examples of suitable protective colloids are polyvinyl alcohol, cellulose derivatives, or copolymers containing vinylpyrrolidone. A comprehensive description of other suitable protective colloids can be found in Houben-Weyl, Methoden der organischenChemie, Vol. XIV / 1, Makromolekulare Stoffe [Macromolecular Compounds], pp. 411-420, Georg-Thieme-Verlag, Stuttgart, 1961. It should be understood that mixtures of emulsifiers and / or protective colloids can also be used. As dispersing aids, it is preferred to use only emulsifiers, whose relative molecular weight is generally less than 1000 g / mol compared to the protective colloid. They can be anionic, cationic, or nonionic in nature. When using mixtures of surfactants, the components must undoubtedly be compatible with each other, and if in doubt, this can be verified by a few preliminary tests. Generally, anionic emulsifiers are compatible with each other and with nonionic emulsifiers. This also applies to cationic emulsifiers, while anionic and cationic emulsifiers are generally incompatible with each other. Commonly used emulsifiers include, for example, alkali metal and ammonium salts of ethoxylated mono, di, and trialkylphenols (EO degree: 3 to 50, alkyl group: C4 to C12), ethoxylated fatty alcohols (EO degree: 3 to 50; alkyl group: C8 to C36); and alkali metal and ammonium salts of alkyl sulfates (alkyl group: C8 to C12), alkali metal and ammonium salts of sulfate monoesters formed with ethoxylated alkanols (EO degree: 4 to 30; alkyl group: C12 to C18) and with ethoxylated alkylphenols (EO degree: 3 to 50; alkyl group: C4 to C12), alkali metal and ammonium salts of alkyl sulfonic acids (alkyl group: C12 to C18), and alkali metal and ammonium salts of alkyl aryl sulfonic acids (alkyl group: C9 to C18). Other suitable emulsifiers can be found in Houben-Weyl, Methoden der organischenChemie, Vol. XIV / 1, Makromolekulare Stoffe [Macromolecular Compounds], pp. 192-208, Georg-Thieme-Verlag, Stuttgart, 1961.

[0137] When using dispersing agents according to the present invention, it is advantageous to use anionic and / or nonionic surfactants, and particularly advantageous to use anionic surfactants.

[0138] It may be advantageous to use emulsifiers that are incorporated into the polymer during free radical emulsion polymerization. These are typically compounds having at least one free radical polymerizable group and at least one emulsifying group, the free radical polymerizable group preferably being selected from the group consisting of allyl, acrylate, methacrylate and vinyl ether, and the emulsifying group preferably being selected from the group indicated above.

[0139] These emulsifiers are, for example, blendable emulsifiers, with trade names such as Bisomer derived from Laporte. ® MPEG 350 MA; Hitenol available from Dai-Ichi Kogyo Seiyaku Co., Ltd. ® BC-20 (APEO), Hitenol ® BC-2020, Hitenol ® KH-10 or Noigen ® RN-50 (APEO); obtained from Croda's Maxemul ® 6106, Maxemul ® 6112, Maxemul ® 5010, Maxemul ® 5011; obtained from Rhodia's Sipomer ® PAM 100, Sipomer ® PAM 200, Sipomer ® PAM 300, Sipomer ® PAM 4000, Sipomer ® PAM 5000; obtained from Adeka. ® Reasoap ® PP-70, Adeka ® Reasoap ® NE-10, Adeka ® Reasoap ® NE-20, Adeka ® Reasoap ® NE-30, Adeka ® Reasoap ® NE-40, Adeka ® Reasoap ® SE-10N, Adeka ® Reasoap ® SE-1025A, Adeka ® Reasoap ® SR-10, Adeka ® Reasoap ® SR-1025, Adeka ® Reasoap ® SR-20, Adeka ® Reasoap® ER-10, Adeka ® Reasoap ® ER-20, Adeka ® Reasoap ® ER-30, Adeka ® Reasoap ® ER-40; obtained from BASF SE's Pluriol ® A 010 R, Pluriol ® A 12 R, Pluriol ® A 23 R, Pluriol ® A 46 R, Pluriol ® A 750 R, Pluriol ® A 950 R, Pluriol ® A 590 I, Pluriol ® A 1190 I, Pluriol ® A590 V, Pluriol ® A 1190 V, Pluriol ® A 5890 V, Pluriol ® A 308 R and DAA ES 8761; derived from Kao's Latemul ® S 180 A and Latemul ® S 180; Eleminol from Sanyou Kasei ® JS-2; Aquaron from Daiichi Kogyou Seiyaku ® HS-1025; and C12-AMPS obtained from Lubrizol.

[0140] Prior to initiating the polymerization reaction, the entirety of the optionally employed dispersant may be included in the initial charge in the aqueous reaction medium. However, another possibility is that, prior to initiating the polymerization reaction, the initial charge in the aqueous reaction medium optionally contains only a portion of the dispersant; then, during the free radical-initiated emulsion polymerization, all or any remaining portion may be added continuously or discontinuously under the polymerization conditions, as needed and as required. Optionally, a portion (≤ 50% by weight) of the dispersant is included in the initial reaction vessel charge, and the remaining amount (≥ 50% by weight) is added continuously by metering.

[0141] However, it is important that free radical-initiated aqueous emulsion polymerization can also be advantageously carried out in the presence of polymer seeds, for example, in the presence of polymer seeds of 0.01 wt% to 10 wt%, usually 0.05 wt% to 7.0 wt%, and often 0.1 wt% to 4.0 wt% based on the total monomer amount in each case.

[0142] In particular, when the particle size of the polymer particles to be prepared by free radical-initiated aqueous emulsion polymerization is set to a controlled size, polymer seeds are used (see, for example, US-A 2520959 and US-A 3397165 in this regard).

[0143] More specifically, polymer seeds with a weight-average particle diameter (Dw) ≤ 100 nm, typically ≥ 5 nm to ≤ 50 nm, and often ≥ 15 nm to ≤ 35 nm are used. The weight-average particle diameter (Dw) is generally determined according to ISO 13321 using a high-performance particle size analyzer from Malvern at 22 °C and a wavelength of 633 nm.

[0144] Polymer seeds are typically used in the form of aqueous polymer dispersions.

[0145] When using polymer seeds, it is advantageous to use exogenous polymer seeds. In-situ polymer seeds are prepared in the reaction vessel prior to the actual emulsion polymerization and typically have the same monomer composition as the polymer prepared via subsequent free radical-initiated aqueous emulsion polymerization. In contrast, exogenous polymer seeds are understood as polymer seeds prepared in a separate reaction step, having a different monomer composition than the polymer prepared via free radical-initiated aqueous emulsion polymerization. This simply means using different monomers or mixtures of monomers with different compositions to prepare the exogenous polymer seeds and the aqueous polymer dispersion. The preparation of exogenous polymer seeds is familiar to those skilled in the art and is typically accomplished by first charging the reaction vessel with a relatively small amount of monomer and a relatively large amount of emulsifier, and then adding a sufficient amount of polymerization initiator at the reaction temperature.

[0146] According to the present invention, exogenous polymer seeds with a glass transition temperature ≥ 50°C, usually ≥ 60°C or ≥ 70°C, and often ≥ 80°C or ≥ 90°C are preferably used. Polystyrene or polymethyl methacrylate polymer seeds are particularly preferred.

[0147] The entire amount of exogenous polymer seed can be included in the initial charge of the polymerization vessel. However, another possibility is that only a portion of the exogenous polymer seed is included in the initial charge of the polymerization vessel, and the remainder is added along with the monomer during polymerization. However, if necessary, the entire amount of polymer seed may also be added during polymerization. Preferably, the total amount of exogenous polymer seed is included in the initial charge of the polymerization vessel before initiating the polymerization reaction.

[0148] Typically, aqueous dispersions of hydroxyl-functionalized polymer P have a solids content of ≥ 35% by weight and ≤ 70% by weight, and advantageously ≥ 40% by weight and ≤ 60% by weight, based on aqueous polymer dispersion c) in each case. The solids content here is determined by drying an aliquot of the aqueous dispersion (approximately 1 g) to constant weight at 120°C in an aluminum pan with an inner diameter of approximately 5 cm.

[0149] To produce a two-component coating composition, the polyisocyanate component (i) and the polyacrylate component (ii) are mixed together.

[0150] Mixing is typically accomplished by stirring the polyisocyanate component into the polyacrylate component, or by stirring the polyacrylate component into the polyisocyanate component.

[0151] In principle, the polyisocyanate component and the polyacrylate component can be mixed by various methods, such as by manual stirring, by shaking, by stirring with a laboratory stirrer at a limited speed, and, in the case of spray application, by combining and mixing the two components in the nozzle. Mixing is preferably accomplished by mechanical stirring. The various methods differ in shear properties, and some mixing methods are only suitable for systems (isocyanates and formulated dispersions) with sufficient stability and appropriate rheological properties.

[0152] The molar ratio of isocyanate groups in the polyisocyanate component to hydroxyl groups in the hydroxyl-functionalized polymer P is typically 0.2:1 to 5:1, preferably 0.8:1 to 2.5:1, and especially 0.9:1 to 2.0:1.

[0153] Two-component coating compositions are particularly suitable for coatings and paints.

[0154] When the above-described two-component coating composition is used to produce coatings and paints, the two-component coating composition may additionally contain pigments, fillers, dispersants, thickeners, preservatives, film-forming aids, flow control and wetting aids, solvents, neutralizers, defoamers, light stabilizers, and / or corrosion inhibitors. These additives are preferably part of component (ii).

[0155] In this case, the pigments that can be used include, in principle, all organic and / or inorganic white and / or colored pigments known to those skilled in the art and with a particle size ≤10,000 nm (Brock, Groteklaes, Mischke, Lehrbuchder Lacktechnologie 2nd ed., U. Zorll, Vincentz Verlag 1998, p. 113).

[0156] The most important white pigments mentioned are titanium dioxide in various modified forms, due to their high refractive indices (rutile: 2.70 and anatase: 2.55) and high hiding power. However, zinc oxide and zinc sulfide are also used as white pigments. These white pigments can be used in coated or uncoated forms. Additionally, organic white pigments are also used, such as non-film-forming hollow polymer particles with high styrene and carboxyl group content, with a particle size of approximately 300 nm to 400 nm (referred to as opaque particles).

[0157] In addition to white pigments, a variety of colored pigments familiar to those skilled in the art can be used to provide color, examples of which are relatively inexpensive inorganic oxides and sulfides of iron, cadmium, chromium and lead, lead molybdate, cobalt blue or carbon black, and relatively expensive organic pigments, examples of which are phthalocyanine, azo pigments, quinacridone, perylene or carbazole.

[0158] In addition to pigments, two-component coating compositions may undoubtedly contain fillers, which are well known to those skilled in the art. Fillers are generally understood to be inorganic materials in powder form with a particle size ≤ 10,000 nm (Brock, Groteklaes, Mischke, Lehrbuch der Lacktechnologie 2nd ed., U. Zorll, Vincentz Verlag 1998, p. 113), which have a lower refractive index compared to pigments (according to DIN 55943 and DIN 55945, the refractive index value of white fillers is <1.7). Fillers in powder form are often naturally occurring minerals, such as calcite, chalk, dolomite, kaolin, talc, mica, diatomaceous earth, barite, quartz, or talc / chlorite symbionts; and synthetically prepared inorganic compounds, such as precipitated calcium carbonate, calcined kaolin or barium sulfate, and calcined silica. Preferred fillers are calcium carbonate in the form of crystalline calcite or amorphous chalk.

[0159] The corrosion inhibitors considered according to the present invention are, in particular, corrosion inhibitors or anti-corrosion pigments.

[0160] Examples of corrosion inhibitors are listed in “Corrosion Inhibitors, 2nd Edition. An Industrial Guide”, edited by Ernest W. Flick, William Andrew Inc. ISBN: 978-0-8155-1330-8. Preferred corrosion inhibitors are hexamine, benzotriazole, phenylenediamine, dimethylethanolamine, polyaniline, sodium nitrite, cinnamaldehyde, condensation products of aldehydes and amines (imines), chromates, nitrites, phosphates, hydrazine, and ascorbic acid.

[0161] Examples of corrosion-resistant pigments are modified zinc orthophosphate (e.g., HEUCOPHOS). ® ZPA, ZPO, and ZMP), polyphosphates (e.g., HEUCOPHOS) ® ZAPP, SAPP, SRPP, and CAPP), WSA-broad-spectrum corrosion inhibitors (e.g., HEUCOPHOS) ® ZAMPLUS and ZCPPLUS), and modified silicate pigments (e.g., HEUCOSIL). ® CTF, Halox ® 750), such as products from Heubach GmbH; and barium borophosphate (e.g., Halox) ® 400), barium phosphosilicate (e.g., Halox) ® BW-111, Halox ® BW-191), calcium borosilicate (e.g., Halox) ® CW-291, CW-22 / 221, CW-2230, calcium phosphosilicate (e.g., Halox) ® CW-491), strontium phosphosilicate (e.g., Halox) ® SW-111) or strontium zinc phosphosilicate (e.g., Halox) ® SZP-391), all from Halox ® company.

[0162] Drying is familiar to those skilled in the art and is accomplished, for example, in a tunnel oven or by flash drying. Drying can also be carried out using NIR radiation, which refers herein to electromagnetic radiation with wavelengths ranging from 760 nm to 2.5 μm, preferably from 900 nm to 1500 nm. Drying can be carried out at temperatures from ambient to 100°C for periods ranging from several minutes to several days.

[0163] Two-component coating compositions, particularly for use in paints and coatings, are suitable for coating substrates such as wood, wood veneer, paper, cardboard, cardboard, fabrics, films, leather, nonwovens, polymer surfaces, glass, ceramics, mineral building materials (such as molded cement bricks and fiber cement boards), or metals, which may optionally be pre-coated or pre-treated in each case. Preferably, the two-component coating compositions are used for coating metals, wood, plastics, and glass.

[0164] These coating compositions are suitable as indoor or outdoor coatings or for use in applications exposed to sunlight, preferably for building components, coatings on (large) vehicles and aircraft, and industrial applications such as commercial vehicles in the agricultural (ACE) and construction sectors, decorative surface coatings, bridges, buildings, power towers, storage tanks, containers, pipelines, power plants, chemical plants, ships, cranes, columns, sheet pile walls, valves, pipes, fittings, flanges, joints, halls, roofs and structural steel, furniture, windows, doors, parquet flooring, can coatings and coil coatings, for ground coverings such as in parking lots or hospitals, and automotive paints for OEM and repair coatings.

[0165] In particular, the coating compositions according to the invention are used as varnish materials, coloring and / or materials containing filler media, in primer systems, or in base coat, intermediate coat or top coat materials.

[0166] This coating composition is preferably used at temperatures ranging from ambient to 80°C, preferably from 5°C to 60°C, and more preferably from 10°C to 40°C. The articles discussed are preferably those that cannot be cured at high temperatures, such as those for large machinery, aircraft, large transport vehicles, and repair coating applications. The coating of the substrate is carried out using conventional methods known to those skilled in the art, wherein at least one coating composition is applied to the substrate to be coated at the desired thickness, and optionally, volatile components optionally contained in the coating composition are removed by heating. This procedure may be repeated once or multiple times if necessary. Application to the substrate can be carried out by known methods, such as spraying, troweling, scraping, brushing, roller application, casting, lamination, back spraying, or co-extrusion.

[0167] The thickness of this layer to be cured can be from 0.1µm to several millimeters, preferably from 1µm to 2000µm, particularly preferably from 5µm to 200µm, and very particularly preferably from 5µm to 60µm (based on the material coating composition in a state where the solvent has been removed from the material coating composition). Example

[0168] The materials used in the examples are as follows:

[0169] <![CDATA[Basonol ® AC 2120 W (obtained from BASF) An aqueous dispersion of polyacrylate polyol with an OH value of 120 mg KOH / g (calculated); approximately 42% by weight in water / 3-butoxyprop-2-ol (51.4 / 6.6). <![CDATA[Bayhydrol ® A 145 (from Covestro) Aqueous polyacrylate polyol with an OH value of 109 mg KOH / g; approximately 45% by weight in water / SN 100 / 2-butoxyethanol; 4% SN 100, 4% 2-butoxyethanol. <![CDATA[Joncryl ® OH 8710 (obtained from BASF) Aqueous polyacrylate polyol with an OH value of 125 mg KOH / g; approximately 46% by weight in water. <![CDATA[Basonat ® HI 3000 (obtained from BASF) Low-viscosity asymmetric isocyanurate based on HDI, which does not contain any modification using anionic groups. <![CDATA[Basonat ® HI 2000 (obtained from BASF) Low viscosity HDI-based polyisocyanate, which contains no modification using anionic groups. <![CDATA[Hydropalat ® WE 3650 (obtained from BASF) wetting agent <![CDATA[EFKA ® SL 3035 (obtained from BASF) Slip modifier / leveling agent <![CDATA[Solvenon ® PnB (obtained from BASF) 3-Butoxyprop-2-ol (solvent) <![CDATA[Rhodiasolv ® RPDE (derived from Solvay) solvent

[0170] Performance testing

[0171] Pendulum stiffness [Oscillation method]

[0172] The coating composition was applied to a 4 mm thick glass plate, pre-cleaned with acetone, using a scraper (gap = 150 µm) to create a wet film. The coated glass plate was dried at 23 °C, and the pendulum hardness was measured after 2 h, 4 h, 1 day, and 7 days. After 7 days, the glass plate was further heated to 40 °C or 60 °C (see table) for 15 hours, and the pendulum hardness was measured again after cooling to 23 °C. The pendulum hardness was measured using a König pendulum according to DIN EN ISO 1522:2006.

[0173] Sand drying time :

[0174] The coating composition was applied to two glass plates using a scraper to achieve a wet film thickness of 150 µm. The two newly coated glass plates were then fixed to a sand particle testing device. A metal cone loaded with sand particles and equipped with two wheels was placed on the coating, and the sand particle outlet was opened to allow fine sand to flow out. The sand-loaded metal cone with wheels moved across the wet film at a constant speed of 1 cm / hour. After 24 hours, the sand particle testing device was closed, the sand particle outlet was shut off, and the cone was removed from the test plates. The sand particles on the plates were shaken off. Sand particles that were located on the coating but not actually adhered to were carefully removed using a brush. The length of the sand particle path was measured with a ruler up to the endpoint of the last sand particle, and this length was converted into time, which was designated as the sand particle drying time.

[0175] Formulation preparation :

[0176] Example Series 1 - Varnish using Basonol AC 2120 W in component A

[0177] Preparation of component A1

[0178] Component A1 was prepared by mixing all components under mechanical mixing. 9.8 g of a 1:1 mixture of N,N-dimethylethanolamine (DMEA):water was added to 700 g of Basonol AC 2120 W, followed by the addition of 40 g of deionized water. Subsequently, 9.03 g of Hydropalat... ® WE 3650 (from BASF; wetting agent) and 3.01g of EFKA ® SL 3035 (from BASF; slip / leveling agent). Stir the mixture at 400 rpm for 5 minutes, then let it stand for 12 hours to obtain easily granulated component A.

[0179] Preparation of component B1 (not according to the present invention) :

[0180] At a mixing speed of 600 rpm, Basonat® HI 3000 (low viscosity HDI-based polyisocyanate) was dissolved in 1-methoxy-2-propyl acetate to give a 70% by weight solution. The mixture was mixed at 600 rpm for 2 minutes.

[0181] Preparation of component B2 (not according to the present invention) :

[0182] Its preparation method is the same as that of component B1, but 2-butoxyethyl acetate is used instead of 1-methoxy-2-propyl acetate.

[0183] Preparation of component B3 (in this invention) :

[0184] Its preparation method is the same as that of component B1, but γ-valerol is used instead of 1-methoxy-2-propyl acetate.

[0185] Preparation of component B4 (not according to the present invention) :

[0186] Its preparation method is the same as that of component B1, but it uses Rhodiasolv. ® RPDE (derived from Solvay) replaces 1-methoxy-2-propyl acetate.

[0187] Preparation of component B5 (not according to the present invention) :

[0188] At a mixing speed of 600 rpm, Basonat ® HI 2000 (HDI-based polyisocyanate) dissolved in Rhodiasolv ® A 65% by weight solution was obtained from RPDE (obtained from Solvay). The mixture was mixed at 600 rpm for 2 minutes.

[0189] Preparation of component B6 (in this invention) :

[0190] Its preparation method is the same as that of component B5, but γ-valerolactone is used instead of Rhodiasolv. ® RPDE.

[0191] Preparation of component B7 (not according to the present invention) :

[0192] Its preparation method is the same as that of component B5, but butyl diethylene glycol acetate (obtained from BASF) is used instead of Rhodiasolv. ® RPDE.

[0193] Preparation of component B8 (not according to the present invention) :

[0194] Its preparation method is the same as that of component B1, but γ-butyrolactone is used instead of 1-methoxy-2-propyl acetate.

[0195] Preparation of component B9 (not according to the present invention) :

[0196] Its preparation method is the same as that of component B5, but Rhodiasolv is replaced with γ-butyrolactone. ® RPDE.

[0197] Formulation of two-component varnish :

[0198] At 600 rpm, 32.7 g of the corresponding component B was added to 100 g of component A1. The mixture was stirred at 1200 rpm for 2 min, 6 g of water was added and mixed to obtain a varnish with a solid content of approximately 45%, which could be applied after waiting for 30 min. Different varnishes were prepared using component A1, with component B varying according to Table 1 to obtain the corresponding varnishes.

[0199] Table 1: Composition of Two-Component Varnishes

[0200] Example Clear varnish code Component A Component B 1 CC-A1B1 Component A1 Component B1 2 CC-A1B2 Component A1 Component B2 3 (This invention) CC-A1B3 Component A1 Component B3 4 CC-A1B4 Component A1 Component B4 5 CC-A1B8 Component A1 Component B8

[0201] The properties of the varnish film studied are listed in Table 2.

[0202] Table 2: Pendulum hardness and drying time of varnishes for components A1 and B1 to B4 and B8

[0203] Clear varnish code Sand drying time [h] Gloss (20° angle) The pendulum stiffness was measured after 4 hours, 1 day, 7 days, and 7 days at room temperature, and also after 15 hours at 40°C [oscillation method]. CC-A1B1 1.0 49 8 / 47 / 111 / 111 CC-A1B2 2.5 65 5 / 38 / 105 / 109 CC-A1B3 3.0 80 4 / 35 / 101 / 104 CC-A1B4 3.5 79 4 / 27 / 99 / 105 CC-A1B8 3.5 18 6 / 51 / 92 / 97

[0204] Compared to CC-A1B4, embodiment CC-A1B3 of the present invention exhibits faster drying while maintaining gloss at a 20° angle. CC-A1B1 and CC-A1B2 exhibit faster drying, but at the cost of a significant loss of gloss. Compared to embodiment CC-A1B3 of the present invention, CC-A1B8 exhibits slower drying and lower gloss.

[0205] Example Series 2 - Use of Bayhydrol in Component A ® A 145 clear coat

[0206] Preparation of component A2

[0207] Component A2 was prepared by mixing all components under mechanical mixing conditions. To 300g of Bayhydrol... ® Add 1.5g of a 1:1 mixture of N,N-dimethylethanolamine (DMEA) and water to product A 145, followed by 5g of deionized water. Then add 3.74g of Hydropalat. ® WE 3650 (from BASF; wetting agent) and 1.35g of EFKA ® SL 3035 (from BASF; slip / leveling agent). Stir the mixture at 400 rpm for 5 minutes, then let it stand for 12 hours to obtain easily granulated component A.

[0208] Formulation of two-component varnish :

[0209] At 600 rpm, 17.7 g of the corresponding component B (corresponding to an isocyanate index of 150, i.e., 1.5 hardener NCO groups / 1 binder OH group) was added to 50 g of component A2. The mixture was stirred at 1200 rpm for 2 min, 5 g of water was added and mixed to obtain a varnish, which could be applied after waiting for 30 min. Different varnishes were prepared using component A2 with different components B, namely components B5, B6, B7 and B9, resulting in the corresponding varnishes CC-A2B5, CC-A2B6, CC-A2B7 and CC-A2B9 (Table 3).

[0210] Table 3: Composition of Two-Component Varnishes

[0211] Clear varnish code Component A Component B CC-A2B5 Component A2 Component B5 CC-A2B6 (This invention) Component A2 Component B6 CC-A2B7 Component A2 Component B7 CC-A2B9 Component A2 Component B9

[0212] The properties of the varnish film studied are listed in Table 4.

[0213] Table 4: Pendulum hardness and drying time of varnishes for components A2 and B5, B6, B7 and B9

[0214] Clear varnish code Sand drying time (h) Gloss (20° angle) The pendulum stiffness was measured after 4 hours, 1 day, 7 days, and 7 days at room temperature, and also after 15 hours at 40°C [oscillation method]. CC-A2B5 4.5 83 2 / 22 / 48 / 81 CC-A2B6 3.5 82 2 / 23 / 41 / 72 CC-A2B7 5.5 83 2 / 8 / 35 / 72 CC-A2B9 4.0 65 2 / 44 / 82 / 65

[0215] Compared to CC-A2B5 and CC-A2B7, embodiment CC-A2B6 of the present invention exhibits faster drying while maintaining gloss at a 20° angle. Compared to CC-A2B9, embodiment CC-A2B6 of the present invention exhibits faster drying and superior gloss.

[0216] Example Series 3 - Varnish using Joncryl OH 8710 in component A

[0217] Preparation of component A3

[0218] Component A3 was prepared by mixing all components under mechanical mixing. 1.35 g of a 1:1 mixture of N,N-dimethylethanolamine (DMEA):water was added to 300 g of Joncryl OH 8710, followed by 5 g of deionized water. 22.95 g of Solvenon was then slowly added over 2 min. ® PnB (obtained from BASF). Then, add 4.05g of Hydropalat. ® WE 3650 (from BASF; wetting agent) and 1.35g of EFKA ® SL 3035 (from BASF; slip / leveling agent). Stir the mixture at 400 rpm for 5 minutes, then let it stand for 12 hours to obtain easily granulated component A.

[0219] Formulation of two-component varnish :

[0220] At 600 rpm, 17.3 g of the corresponding component B (corresponding to an isocyanate index of 135, i.e., 1.35 hardener NCO groups / 1 binder OH group) was added to 50 g of component A3. The mixture was stirred at 1200 rpm for 2 min, 2 g of water was added and mixed to obtain a varnish, which could be applied after waiting for 30 min. Different varnishes were prepared using component A3 with different components B, namely components B5, B6, B7 and B9, to obtain the corresponding varnishes CC-A3B5, CC-A3B6, CC-A3B7 and CC-A3B9 (Table 5).

[0221] Table 5: Composition of Two-Component Varnishes

[0222] Clear varnish code Component A Component B CC-A3B5 Component A3 Component B5 CC-A3B6 (This invention) Component A3 Component B6 CC-A3B7 Component A3 Component B7 CC-A3B9 Component A3 Component B9

[0223] The properties of the varnish film studied are listed in Table 6.

[0224] Table 6: Ballast hardness and drying time of varnishes for components A3 and B5, B6, B7 and B9

[0225] Clear varnish code Sand drying time (h) Gloss (20° angle) The pendulum stiffness was measured after 4 hours, 1 day, 7 days, and 7 days at room temperature, and also after 15 hours at 40°C [oscillation method]. CC-A3B5 5.0 49 2 / 49 / 114 / 115 CC-A3B6 4.5 75 2 / 58 / 109 / 106 CC-A3B7 6.0 77 2 / 11 / 74 / 101 CC-A3B9 5.0 22 4 / 97 / 120 / 110

[0226] Compared to CC-A3B7, embodiment CC-A3B6 of the present invention exhibits faster drying while maintaining a nearly similar level of gloss at a 20° angle; and compared to CC-A3B5 and CC-A3B9, CC-A3B6 exhibits faster drying and superior gloss at a 20° angle.

[0227] Example Series 4 - Use of Basonol in Component A ® AC 2120 W clear coat

[0228] Preparation of component A4

[0229] Component A4 was prepared by mixing all components under mechanical mixing conditions. To 300g of Basonol... ® AC 2120 W was prepared by adding 4.70 g of a 1:1 mixture of N,N-dimethylethanolamine (DMEA) and water, followed by the addition of 17 g of deionized water. Subsequently, 3.92 g of Hydropalat was added. ® WE 3650 (from BASF; wetting agent) and 1.35g of EFKA ® SL 3035 (from BASF; slip / leveling agent). Stir the mixture at 400 rpm for 5 minutes, then let it stand for 12 hours to obtain easily granulated component A.

[0230] Formulation of two-component varnish :

[0231] At 600 rpm, 16.14 g of the corresponding component B (corresponding to an isocyanate index of 135, i.e., 1.35 hardener NCO groups / 1 binder OH group) was added to 50 g of component A4. The mixture was stirred at 1200 rpm for 2 min, 8 g of water was added and mixed to obtain a varnish, which could be applied after waiting for 30 min. Different varnishes were prepared using component A4 with different components B, namely components B5, B6, B7 and B9, to obtain the corresponding varnishes CC-A4B5, CC-A4B6, CC-A4B7 and CC-A4B9 (Table 7).

[0232] Table 7: Composition of Two-Component Varnishes

[0233] Clear varnish code Component A Component B CC-A4B5 Component A4 Component B5 CC-A4B6 (This invention) Component A4 Component B6 CC-A4B7 Component A4 Component B7 CC-A4B9 Component A4 Component B9

[0234] The properties of the varnish film studied are listed in Table 8.

[0235] Table 8: Pendulum hardness and drying time of varnishes for components A4, B5, B6, B7, and B9

[0236] Clear varnish code Sand drying time (h) Gloss (20° angle) The pendulum stiffness was measured after 4 hours, 1 day, 7 days, and 7 days at room temperature, and also after 15 hours at 40°C [oscillation method]. CC-A4B5 4.5 82 2 / 31 / 83 / 104 CC-A4B6 3.5 81 2 / 34 / 85 / 99 CC-A4B7 4.5 78 2 / 15 / 58 / 88 CC-A4B9 3.5 25 7 / 49 / 85 / 89

[0237] Compared to CC-A4B5 and CC-A4B7, embodiment CC-A4B6 of the present invention exhibits faster drying while maintaining gloss at a 20° angle. Compared to CC-A4B9, embodiment CC-A4B6 of the present invention exhibits superior gloss at a comparable drying time.

Claims

1. A two-component coating composition comprising: component (i), which is a composition comprising: ia) at least one polyisocyanate, and (ib) at least one γ-lactone having one or two groups selected from C1-C6 alkyl, C1-C6-alkoxy, and methylcarboxylic acid-C1-C4 alkyl groups. And component (ii), which comprises an aqueous dispersion of at least one hydroxyl-functionalized polymer P.

2. The two-component coating composition according to claim 1, wherein the γ-lactone has a C1-C4 alkyl group.

3. The two-component coating composition according to claim 1 or 2, wherein the γ-lactone is γ-valerolactone.

4. The two-component coating composition according to any one of claims 1 to 3, wherein the at least one γ-lactone has a content of 0.5 × 10⁻⁶. -12 Up to 5×10 -12 of 14 C / 12 C isotope ratio.

5. The two-component coating composition according to any one of claims 1 to 4, wherein the polyisocyanate (ia) contains up to 0.01 molar equivalents of isocyanate groups selected from anionic groups and / or polyethylene oxide blocks.

6. The two-component coating composition according to any one of claims 1 to 5, wherein the polyisocyanate (ia) is an aliphatic and / or cycloaliphatic polyisocyanate.

7. The two-component coating composition according to any one of claims 1 to 6, wherein the polyisocyanate (ia) has an average NCO functionality in the range of 2.4 to 4.

0.

8. The two-component coating composition according to any one of claims 1 to 7, wherein component (i) comprises 5% to 50% by weight of the γ-lactone based on the sum of the polyisocyanate (ia) and the γ-lactone (ib).

9. The two-component coating composition according to any one of claims 1 to 8, wherein the hydroxyl-functionalized polymer P is a polyacrylate polyol.

10. The two-component coating composition according to any one of claims 1 to 9, wherein the hydroxyl-functionalized polymer has a hydroxyl value of 15 mg KOH / g to 250 mg KOH / g.

11. The two-component coating composition according to any one of claims 1 to 10, wherein the hydroxyl-functionalized polymer P is prepared by polymerization of the following substances: Ma) at least one hydroxyl-functionalized (meth)acrylate, and Mb) at least one monomer selected from the group consisting of: (meth)acrylate alkyl esters, vinyl aromatic compounds, α,β-unsaturated carboxylic acids and other monomers.

12. The two-component coating composition according to any one of claims 1 to 11, wherein the hydroxyl-functional polymer P is prepared by free radical-initiated aqueous emulsion polymerization.

13. The two-component coating composition according to any one of claims 1 to 12, wherein the molar ratio of the isocyanate group in the polyisocyanate component (ia) to the hydroxyl group in the hydroxyl-functionalized polymer P is 0.8:1 to 2.5:

1.

14. A method for producing a two-component coating composition according to at least one of claims 1 to 13, wherein the component (i) and the component (ii) are mixed with each other.

15. Use of the two-component coating composition according to any one of claims 1 to 13 for coating metals, wood, plastics and glass.