Solvent-borne coating compositions containing water-dispersible polyisocyanates

Abstract

The present disclosure relates to a solvent-borne coating composition comprising an aqueous dispersible polyisocyanate, a method of coating a substrate using such a composition, a substrate comprising a cured coating composition, and a method of manufacturing the same. And the use of a water-dispersible polyisocyanate in a solvent-borne coating composition for improving the chemical resistance, scratch resistance and / or wear resistance of such coatings.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a solvent-based coating composition comprising a water-dispersible polyisocyanate, a method of coating a substrate using such a composition, a substrate comprising a cured coating composition, and the use of a water-dispersible polyisocyanate in a solvent-based coating composition for improving the chemical resistance, scratch resistance, and / or abrasion resistance of such coatings. BACKGROUND OF THE INVENTION

[0002] It is generally desirable to provide a cured coating composition on the surface of a substrate in various technical fields such as vehicles, while providing resistance properties and a desired appearance. Conventional solvent-based multi-component polyurethane coating compositions known in the coating industry generally exhibit good appearance properties (such as gloss), but cannot provide good resistance properties at the same time.

[0003] Therefore, it is desirable to provide solvent-based multi-component polyurethane coating compositions that provide improved resistance properties such as scratch resistance, chemical resistance, and / or abrasion resistance without compromising the appearance.

[0004] This is achieved by the subject matter defined in the appended claims. It has surprisingly been found that by incorporating a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group into a solvent-based coating composition, the chemical resistance and scratch resistance of the cured coating can be improved without deteriorating the appearance or even improving the appearance. SUMMARY OF THE INVENTION

[0005] The present disclosure relates to a multi-component coating composition comprising: a first solvent-based component comprising a polyfunctional compound containing active hydrogen; and a second solvent-based component comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group.

[0006] The present disclosure also relates to a solvent-based composition comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group and at least one solvent selected from the group consisting of aromatics, alkyl acetates, or combinations thereof.

[0007] The present disclosure further relates to a method of coating a substrate, the method comprising applying a coating composition to at least a portion of the surface of the substrate to form a coating layer, the coating composition comprising: a first solvent-based component comprising a polyfunctional compound containing active hydrogen; and a second solvent-based component comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group.

[0008] The present disclosure also relates to a substrate comprising a cured coating layer obtained from the multi-component coating composition disclosed herein.

[0009] The present disclosure further relates to the use of a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group as a curing agent in a solvent-based coating composition for the following purposes: improving the chemical resistance, scratch resistance, abrasion resistance, and / or appearance of the coating obtained from the coating composition as compared to the coating obtained from the same coating composition cured with a polyisocyanate having neither a sulfonic acid group nor a phosphoric acid ester ether group. Detailed Description

[0010] For the purposes of the following detailed description, it should be understood that the present disclosure may take various alternative variations and step sequences, unless the contrary is expressly stated. In addition, except in any operating examples or where otherwise indicated, all numbers expressing quantities of ingredients, for example, used in the specification and claims, are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0011] Although the numerical ranges and parameters setting forth the broad scope of the present disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0012] Moreover, it should be understood that any numerical range recited herein is intended to include all subranges subsumed therein. For example, a range of "1 to 10" is intended to include all subranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.

[0013] In this application, unless otherwise specifically stated, the use of the singular includes the plural, and the plural encompasses the singular. Additionally, in this application, unless otherwise specifically stated, the use of "or" means "and / or", even though in some cases "and / or" may be expressly used. Further, in this application, unless otherwise specifically stated, the use of "a" or "an" means "at least one". For example, "a" polymer, "a" pigment, etc. refer to any one or more of these items.

[0014] The present disclosure relates to a multi-component coating composition comprising: a first solvent-based component comprising a polyfunctional compound containing active hydrogen; and a second solvent-based component comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group.

[0015] The multi-component coating composition can comprise 50 wt% to 90 wt% of a first component and 10 wt% to 50 wt% of a second component based on the total weight of the combined resin solids of the first and second components. The multi-component composition can comprise 50 wt% to 90 wt%, such as 60 wt% to 90 wt%, such as 70 wt% to 90 wt%, such as 80 wt% to 90 wt% of the first component and 10 wt% to 50 wt%, such as 10 wt% to 40 wt%, such as 10 wt% to 30 wt%, such as 10 wt% to 20 wt% of the second component based on the total weight of the combined resin solids of the first and second components. The multi-component composition can comprise 50 wt% to 90 wt% of the first component and 10 wt% to 50 wt% of the second component, such as 60 wt% to 90 wt% of the first component and 10 wt% to 40 wt% of the second component, such as 70 wt% to 90 wt% of the first component and 10 wt% to 30 wt% of the second component, such as 80 wt% to 90 wt% of the first component and 10 wt% to 20 wt% of the second component, such as 50 wt% to 80 wt% of the first component and 20 wt% to 50 wt% of the second component, such as 50 wt% to 70 wt% of the first component and 30 wt% to 50 wt% of the second component, such as 50 wt% to 60 wt% of the first component and 40 wt% to 50 wt% of the second component. The multi-component composition can comprise 70 wt% to 80 wt% of the first component and 20 wt% to 30 wt% of the second component based on the total weight of the combined resin solids of the first and second components.

[0016] The terms "resin", "resinous", etc. are used interchangeably with the terms "polymer", "polymeric", etc. Further, the term "polymer" is used herein in its ordinary meaning in the art, referring to a macromolecular compound, i.e., a compound having a relatively high molecular weight (e.g., 500 Da or higher), the structure of which comprises a plurality of repeating units (also referred to as "mers") actually or conceptually derived from a chemical substance of relatively low molecular weight. Unless otherwise specified, the molecular weight is based on a weight-average basis ("M w w") and is determined by gel permeation chromatography using polystyrene standards.

[0017] According to the present disclosure, a "polyfunctional compound containing active hydrogen" refers to a compound containing more than one moiety having a hydrogen atom, which exhibits significant activity according to the Zerewitinoff test described by Wohler in Journal of the American Chemical Society, Volume 49, Page 3181 (1927) due to its position in the molecule. Suitable moieties having active hydrogen include, but are not limited to, -COOH, -OH, -NH2, -NH-, -CONH2, -SH, and -CONH-. The polyfunctional compound containing active hydrogen may be selected from the group consisting of polyols, polyamines, polythiols, and mixtures thereof.

[0018] The polyfunctional compound containing active hydrogen may comprise a polyol or may be a polyol. As used herein, the term "polyol" refers to a compound having more than one hydroxyl group per molecule, such as 2, 3, 4, 5, 6, or more hydroxyl groups per molecule. The polyol may be an oligomeric or polymeric compound. In particular, the polyol may be a polymeric polyol.

[0019] Based on the total weight of the resin solids in the first solvent-based component, the polyol may be present in the first solvent-based component in an amount of at least 30 wt%, such as at least 40 wt%, such as at least 50 wt%, such as at least 60 wt%, such as at least 70 wt%, such as at least 80 wt%. Based on the total weight of the resin solids in the first solvent-based component, the polyol may be present in the first solvent-based component in an amount not exceeding 99.8 wt%, such as not exceeding 95 wt%, such as not exceeding 90 wt%, such as not exceeding 85 wt%. Based on the total weight of the resin solids in the first solvent-based component, the range of the polyol may include, for example, 30 wt% to 99.8 wt%, such as 30 wt% to 95 wt%, such as 30 wt% to 90 wt%, such as 30 wt% to 85 wt%, such as 40 wt% to 99.8 wt%, such as 50 wt% to 99.8 wt%, such as 60 wt% to 99.8 wt%, such as 70 wt% to 99.8 wt%, such as 80 wt% to 99.8 wt%. Based on the total weight of the resin solids in the first solvent-based component, the polyol may be present in the coating composition in a range between any of the above values, such as 40 wt% to 95 wt%, such as 50 wt% to 90 wt%, such as 60 wt% to 85 wt%, such as 70 wt% to 85 wt%.

[0020] The polyol in the first solvent-based component may comprise a (meth)acrylic polyol, a polyester polyol, or a combination thereof.

[0021] Suitable (meth)acrylic polyols can be homopolymers or copolymers, which can be obtained by polymerizing one or more hydroxyl-functional monomers comprising a hydroxylated (meth)acrylic acid and a (meth)acrylate. As used herein, the terms “(meth)acrylic acid,” “(meth)acrylate,” and similar terms refer to acrylic acid or acrylate and the corresponding methacrylic acid or methacrylate, respectively. Non-limiting examples of acrylic polyols can include acrylic polyols derived from 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 9-hydroxynonyl (meth)acrylate, acrylic polyols derived from glycidyl ester (meth)acrylic acid adducts or acrylic acid adducts of glycidyl neodecanoate, which is commercially available under the trade name Cardura TM E10 and is commercially available from Hexion Inc. (Columbus, USA). The acrylic polyol can have a hydroxyl value in the range of 20 mg KOH / g to 400 mg KOH / g, such as 30 mg KOH / g to 350 mg KOH / g, such as 40 mg KOH / g to 300 mg KOH / g, such as 50 mg KOH / g to 250 mg KOH / g. The hydroxyl value can be determined according to DIN EN ISO 4629-1:2016. Suitable acrylic polyols that can be used include, but are not limited to, acrylic polyol resins commercially available under the trademarks commercially available acrylic polyol resins, such as those commercially available from Allnex Deutschland GmbH (Frankfurt, Germany) 1776VS-65, 1774SS-70, 1797SS-70, 1762W-70, 1760VB-64, 1795VX-74, DA 870BA, and acrylic polyol resins commercially available under the trademark such as VIACRYL SC370 / 75SNA commercially available from Allnex Deutschland GmbH (Frankfurt, Germany).

[0022] Suitable polyester polyol resins can be prepared in a known manner, for example, by the condensation of polyols and polycarboxylic acids or by the ring-opening polymerization of lactones. Suitable polyols include, but are not limited to, alkylene diols such as ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, polyethylene glycol having a molecular weight in the range of 200 g / mol to 10,000 g / mol, polypropylene glycol having a molecular weight in the range of 200 g / mol to 10,000 g / mol, polybutylene glycol having a molecular weight in the range of 300 g / mol to 10,000 g / mol, and neopentyl glycol; bisphenol A; hydrogenated bisphenol A; bisphenol F; hydrogenated bisphenol F; cyclohexanediol; propylene glycols such as 1,2-propylene glycol, 1,3-propylene glycol, 2-methyl-1,3-propylene glycol, and 2-ethyl-2-butyl-1,3-propylene glycol; butylene glycols such as 1,4-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1,2-butylene glycol, 3-methyl-1,2-butylene glycol, and 2-ethyl-1,4-butylene glycol; pentylene glycols such as 1,2-pentylene glycol, 1,5-pentylene glycol, 1,4-pentylene glycol, 3-methyl-4,5-pentylene glycol, and 2,2,4-trimethyl-1,3-pentylene glycol; hexylene glycols such as 1,6-hexylene glycol, 1,5-hexylene glycol, 1,4-hexylene glycol, and 2,5-hexylene glycol; poly(ε-caprolactone) diol having a molecular weight in the range of 400 g / mol to 10,000 g / mol; polyether diols such as poly(oxytetramethylene) glycol; trimethylolpropane; pentaerythritol; dipentaerythritol; trimethylolethane; trimethylolbutane; dimethylolcyclohexane; and glycerol. Suitable polycarboxylic acids can include, but are not limited to, maleic acid; fumaric acid; itaconic acid; adipic acid; azelaic acid; succinic acid; sebacic acid; glutaric acid; phthalic acid; isophthalic acid; 5-tert-butylisophthalic acid; tetrachlorophthalic acid; trimellitic acid; naphthalenedicarboxylic acid; naphthalenetetracarboxylic acid; terephthalic acid, hexahydrophthalic acid; methylhexahydrophthalic acid; dimethylterephthalic acid; cyclohexanedicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid; 1,4-cyclohexanedicarboxylic acid; tricyclodecane polycarboxylic acid, endomethylenetetrahydrophthalic acid; endoethylidenehexahydrophthalic acid; cyclohexanetetracarboxylic acid; cyclobutanetetracarboxylic acid; and the acid anhydrides, acyl halides, or esters of all of the above polyacids. Suitable lactones can include, but are not limited to, β-propiolactone; γ-butyrolactone; δ-valerolactone; ε-caprolactone; α-angelica lactone; and mixtures thereof. Suitable polyester polyols that can be used include, but are not limited to, polyester polyol resins commercially available under the trademark commercially available polyester polyol resins such as those commercially available from Evonik Deutschland GmbH (Frankfurt, Germany) 1715VX-74, 91703SS-53, and 91715SS-55. Suitable polyester polyols that can be used include, but are not limited to, branched polyester polyols such as the branched polyester polyol resin with the trademark as an example, such as Basonol HPE 1170B commercially available from BASF SE (Ludwigshafen, Germany) or AV 2113 commercially available from Covestro (Leverkusen, Germany).

[0023] The active hydrogen-containing polyfunctional compound according to the present disclosure may contain a polyamine or may be a polyamine. The term "polyamine" as used herein refers to a compound having more than one amino group per molecule, for example, 2, 3, 4, 5, 6 or more amino groups per molecule. Suitable polyamines include, but are not limited to, ethylenediamine; hexamethylenediamine; 1-methyl-2,6-cyclohexanediamine; tetrahydroxypropylene ethylenediamine; 2,2,4-trimethyl-1,6-hexanediamine and 2,4,4-trimethyl-1,6-hexanediamine; 4,4'-bis-(sec-butylamino)-dicyclohexylmethane; 1,4-bis-(sec-butylamino)-cyclohexane; 1,2-bis-(sec-butylamino)-cyclohexane; derivatives of 4,4'-bis-(sec-butylamino)-dicyclohexylmethane; 4,4'-dicyclohexylmethanediamine; 1,4-cyclohexane-bis-(methylamine); 1,3-cyclohexane-bis-(methylamine); diethylene glycol bis(aminopropyl) ether; 2-methylpentamethylenediamine: diaminocyclohexane; diethylenetriamine; triethylenetetramine; tetraethylenepentamine; propylenediamine; 1,3-diaminopropane; iminodipropylamine; isophoronediamine; 4,4'-methylenebis-(2-chloroaniline); 3,5-dimethylthio-2,4-toluenediamine; 3,5-dimethylthio-2,6-toluenediamine; 3,5-diethylthio-2,4-toluenediamine; 3,5-diethylthio-2,6-toluenediamine; 4,4'-bis-(sec-butylamino)-diphenylmethane and its derivatives; 1,4-bis-(sec-butylamino)-benzene; 1,2-bis-(sec-butylamino)-benzene; N,N'-dialkylamino-diphenylmethane; triethylene glycol di-p-aminobenzoate; polytetramethylene oxide di-p-aminobenzoate; 4,4'-methylenebis-(3-chloro-2,6-diethylaniline); 4,4'-methylenebis-(2,6-diethylaniline); m-phenylenediamine; p-phenylenediamine; and mixtures thereof. The polyamine may have a molecular weight of 64 g / mol or greater. The polyamine may have a molecular weight of 2000 g / mol or less.

[0024] The active hydrogen-containing polyfunctional compound according to the present disclosure may comprise a polythiol or may be a polythiol. As used herein, the term "polythiol" refers to a compound having more than one thiol group per molecule, such as 2, 3, 4, 5, 6 or more thiol groups per molecule. Suitable polythiols include, but are not limited to, linear or branched aliphatic, cycloaliphatic, aromatic, heterocyclic, polymeric or oligomeric dithiols such as 1,2-ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 1,3-butanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,3-pentanedithiol, 1,5-pentanedithiol, 1,6-hexanedithiol, dimercapto diethyl sulfide (DMDS), 1,3-dimercapto-3-methylbutane, dipentene dithiol, ethylcyclohexyl dithiol (ECHDT), methyl-substituted dimercapto diethyl sulfide, dimethyl-substituted dimercapto diethyl sulfide, 3,6-dioxa-1,8-octanedithiol, 1,5-dimercapto-3-oxapentane, 2,5-dimercaptomethyl-1,4-dithiane (DMMD), ethylene glycol bis(2-mercaptoacetate), ethylene glycol bis(3-mercaptopropionate), benzenedithiol, 4-tert-butyl-1,2-benzenedithiol, 4,4'-thiobisbenzenethiol; and higher functionality polythiols such as pentaerythritol tetra(2-mercaptoacetate), pentaerythritol tetra(3-mercaptopropionate), trimethylolpropane tris(2-mercaptoacetate), trimethylolpropane tris(3-mercaptopropionate) and thioglycerol bis(2-mercaptoacetate), and mixtures of any of the foregoing.

[0025] The second solvent-based component of the multi-component composition according to the present disclosure comprises a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group, and may further optionally comprise a second polyisocyanate having neither a sulfonic acid group nor a phosphoric acid ester ether group.

[0026] The polyisocyanates according to the present disclosure can be aliphatic, aromatic, or mixtures thereof. As used herein, the term "aliphatic" refers to acyclic or cyclic, saturated or unsaturated hydrocarbon compounds. As used herein, the term "aromatic" refers to compounds containing one or more rings with π electrons delocalized throughout. As used herein, the term "polyisocyanate" is intended to include blocked polyisocyanates as well as unblocked polyisocyanates. As used herein, the term "blocked polyisocyanate" refers to an adduct derived from the equilibrium reaction of an isocyanate with a blocking agent, whereby the adduct is thermally unstable and dissociates (unblocks) at elevated temperatures (such as temperatures above 100 °C or above 120 °C). The term "unblocked isocyanate" refers to a polyisocyanate having free isocyanate groups (i.e., a polyisocyanate without a blocking agent). The polyisocyanates can be prepared from various isocyanate-containing materials. Examples of suitable polyisocyanates include (but are not limited to) trimers prepared from toluene diisocyanate, 4,4'-methylene-bis(cyclohexyl isocyanate), isophorone diisocyanate, an isomeric mixture of 2,2,4- and 2,4,4-trimethylhexamethylene diisocyanate, 1,6-hexamethylene diisocyanate, tetramethylxylylene diisocyanate, and / or 4,4'-diphenylmethane diisocyanate. The isocyanate groups of the polyisocyanate can be blocked or unblocked as desired. Examples of suitable blocking agents include materials that unblock at elevated temperatures (e.g., at temperatures above 100 °C), such as lower aliphatic alcohols having 1 to 6 carbon atoms, which include methanol, ethanol, and n-butanol; cycloaliphatic alcohols, such as cyclohexanol; aromatic alkyl alcohols, such as benzyl alcohol and methylphenylmethanol; and phenolic compounds, such as phenol itself and substituted phenols where the substituents do not affect the coating operation, such as cresol and nitrophenol. Glycol ethers can also be used as blocking agents. Suitable glycol ethers include ethylene glycol butyl ether, diethylene glycol butyl ether, ethylene glycol methyl ether, and propylene glycol methyl ether. Other suitable blocking agents include: oximes, such as methyl ethyl ketoxime, acetone oxime, and cyclohexanone oxime; lactams, such as ε-caprolactam; pyrazoles, such as dimethylpyrazole; and amines, such as dibutylamine.

[0027] As used herein, the term "water-dispersible polyisocyanate" refers to a polyisocyanate containing hydrophilic functional groups in an amount such that the polyisocyanate can be dissolved, stably dispersed and / or emulsified in water at room temperature (23 °C) without using an external surfactant or emulsifier, such that the dispersion and / or emulsion, once formed by mixing, does not separate when left standing at room temperature for at least one hour. As used herein, the term "dissolved" means that the water-dispersible polyisocyanate has a solubility in water at room temperature of at least 1.0 g / l. The water-dispersible polyisocyanate used according to the present disclosure is modified with hydrophilic sulfonic acid groups or phosphoric acid ester ether groups. Suitable water-dispersible polyisocyanates having sulfonic acid groups or phosphoric acid ester ether groups can be prepared by: preparing a polyisocyanate as described above and modifying the polyisocyanate by reaction with an ionic compound having sulfonic acid groups and / or phosphoric acid ester ether groups. The ionic compound can further have a group reactive with an isocyanate group, such as an alcohol group or an amine group. Suitable ionic compounds for modifying the polyisocyanate can be exemplified by 2-[(2-aminoethyl)-amino]-ethanesulfonic acid. Alternatively, a water-dispersible polyisocyanate can be prepared by: reacting a polyisocyanate as described above with a phosphoric acid ester having a polyoxyalkylene chain (such as polyoxyethylene tridecyl ether phosphate). The water-dispersible polyisocyanate can be a trimer prepared from an aliphatic diisocyanate. The water-dispersible polyisocyanate can have an NCO content on solids in the range of 8% to 25%, such as 8% to 20%, such as 8% to 15%, such as 10% to 25%, such as 15% to 25%, such as 20% to 25%. The NCO content can be determined according to DIN EN ISO 11 909:2007-5. As used herein, the term "NCO content on solids" refers to the amount of NCO groups based on the total amount of the solids of the polyisocyanate once the volatiles have evaporated. The water-dispersible polyisocyanate can be prepared from an aliphatic diisocyanate. Suitable water-dispersible polyisocyanates having sulfonic acid groups or phosphoric acid ester ether groups can be exemplified by Aquolin 270 or Aquolin 278 commercially available from Wanhua Chemical Group (Yantai, China), Bayhydur polyisocyanates (such as Bayhydur 2655 and Bayhydur 2547) commercially available from Covestro (Leverkusen, Germany) or Easaqua X M 505 commercially available from Vencorex (Saint Priest, France).

[0028] Suitable polyisocyanates that do not have sulfonic acid groups or phosphoric acid ester ether groups as used in the present disclosure can be prepared as described above. The polyisocyanate that does not have sulfonic acid groups or phosphoric acid ester ether groups can be a trimer prepared from aliphatic diisocyanates. The polyisocyanate that does not have sulfonic acid groups or phosphoric acid ester ether groups can have an NCO content on solids in the range of 8% to 25%, such as 8% to 20%, such as 8% to 15%, such as 10% to 25%, such as 15% to 25%, such as 20% to 25%. The NCO content can be determined according to DIN EN ISO 11 909:2007-5. According to the present disclosure, the polyisocyanate that does not have sulfonic acid groups or phosphoric acid ester ether groups can be used as the second polyisocyanate in the second component of a multi-component coating composition. The second polyisocyanate can be an aliphatic polyisocyanate. Suitable polyisocyanates that do not have sulfonic acid groups or phosphoric acid ester ether groups and can be used as the second polyisocyanate include, but are not limited to, Desmodur grades of polyisocyanates commercially available from Covestro (Leverkusen, Germany), such as Desmodur DN, Desmodur N 3300, Desmodur IL EA, and Desmodur N 3300BA / SN.

[0029] Based on the total weight of the resin solids in the second solvent-based component, the polyisocyanate can be present in the second solvent-based component in an amount of at least 30% by weight, such as at least 40% by weight, such as at least 50% by weight, such as at least 60% by weight, such as at least 70% by weight, such as at least 80% by weight. Based on the total weight of the resin solids in the second solvent-based component, the polyisocyanate can be present in the second solvent-based component in an amount not exceeding 90% by weight, such as not exceeding 85% by weight, such as not exceeding 80% by weight. Based on the total weight of the resin solids in the second solvent-based component, the range of the polyisocyanate can include, for example, 30% to 90% by weight, such as 30% to 85% by weight, such as 30% to 80% by weight, such as 40% to 90% by weight, such as 50% to 90% by weight, such as 60% to 90% by weight, such as 70% to 90% by weight, such as 80% to 90% by weight. Based on the total weight of the resin solids in the second solvent-based component, the polyisocyanate can be present in the coating composition in a range between any of the above values, such as 40 to 85% by weight, such as 50 to 85% by weight, such as 60 to 80% by weight, such as 70 to 85% by weight.

[0030] In the composition according to the present disclosure, when a second polyisocyanate that has neither a sulfonic acid group nor a phosphoric acid ester ether group is additionally used, the water-dispersible polyisocyanate and the second polyisocyanate can be used in a weight ratio of 1:10 to 10:1 or 5:1 to 1:5 or 3:1 to 1:3 or 2:1 to 1:2. For example, the water-dispersible polyisocyanate and the second polyisocyanate can be used in a ratio of 1:1.

[0031] The first solvent-based component can further include a melamine compound. The term "melamine compound" refers to melamine (2,4,6-triamino-1,3,5-triazine) itself and resins obtained by polymerizing melamine with another compound such as, for example, formaldehyde. The melamine compound can have an equivalent weight of 60 g / eq to 300 g / eq. As used herein, "equivalent" refers to the mass of the melamine compound having one mole (equivalent) of reactive groups. Based on the total weight of the resin solids in the first solvent-based component, the melamine compound can be present in the first solvent-based component in an amount of at least 0.2 wt%, such as at least 1 wt%, such as at least 5 wt%, such as at least 10 wt%. Based on the total weight of the resin solids in the first solvent-based component, the melamine compound can be present in the first solvent-based component in an amount of not more than 30 wt%, such as not more than 25 wt%, such as not more than 20 wt%, such as not more than 15 wt%. Based on the total weight of the resin solids in the first solvent-based component, the melamine compound can be present in the coating composition in a range between any of the above values, such as 0.2 wt% to 30 wt%, such as 0.2 wt% to 25 wt%, such as 0.2 wt% to 20 wt%, such as 0.2 wt% to 15 wt%, such as 1 wt% to 30 wt%, such as 1 wt% to 25 wt%, such as 1 wt% to 20 wt%, such as 1 wt% to 15 wt%, such as 5 wt% to 30 wt%, such as 5 wt% to 25 wt%, such as 5 wt% to 20 wt%, such as 5 wt% to 15 wt%, such as 10 wt% to 30 wt%, such as 10 wt% to 25 wt%, such as 10 wt% to 20 wt%, such as 10 wt% to 15 wt%.

[0032] The coating composition may further comprise at least one additional component selected from the following: additional polymers different from the above-mentioned active hydrogen-containing polyfunctional compounds, UV stabilizers, UV absorbers, curing catalysts, corrosion inhibitors, adhesion promoters, rheology modifiers, leveling agents, sag control agents, surfactants, fillers, matting agents, wear-resistant particles, colorants, antioxidants, reactive diluents, plasticizers, and effect pigments. When used, based on the total solid weight of the coating composition, the coating composition may comprise a total of 0.1 wt% to 45 wt% of these additional components, such as 1 wt% to 40 wt%, such as 1.5 wt% to 35 wt%.

[0033] As used herein, "additional polymers different from the active hydrogen-containing polyfunctional compounds" refers to polymers that do not contain any of the above-mentioned active hydrogen functional groups and / or do not react with the isocyanate groups of polyisocyanates under the curing conditions employed. For example, when the active hydrogen-containing polyfunctional compound comprises a polyol or is a polyol, the additional polymer does not represent a polyol, particularly does not represent a (meth)acrylic polyol or a polyester polyol, such as but not limited to an acrylic resin different from an acrylic polyol, i.e., does not have multiple hydroxyl groups, vinyl resins, polysiloxane resins, epoxy resins, polyamide resins, copolymers thereof, or mixtures thereof.

[0034] Suitable acrylic resins different from acrylic polyols may be homopolymers or copolymers, which may be obtained by polymerizing one or more monomers comprising substituted or unsubstituted (meth)acrylic acid and (meth)acrylic esters. The acrylic resin may have a linear, branched, star, graft, block, alternating, or gradient structure, or any mixture comprising a combination thereof. Suitable (meth)acrylic esters may include but are not limited to (meth)acrylic acid alkyl esters, (meth)acrylic acid cycloalkyl esters, (meth)acrylic acid alkyl cycloalkyl esters, (meth)acrylic acid aralkyl esters, (meth)acrylic acid alkyl aryl esters, (meth)acrylic acid aryl esters, and functional group-containing (meth)acrylic esters. As used herein, the term "functional group" refers to a group comprising one or more atoms other than hydrogen and sp 3Groups of atoms other than carbon atoms. Examples of functional groups include, but are not limited to, carboxylic acids, amide groups, isocyanates, urethanes, thiols, amines, sulfones, sulfoxides, phosphines, phosphites, phosphates, and halides, etc. Non-limiting examples of acrylic resins can include acrylic resins derived from the following: methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isobornyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, hexadecyl (meth)acrylate, octadecyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, 3-methylphenyl (meth)acrylate, 1-naphthyl (meth)acrylate, 3-phenyl-n-propyl (meth)acrylate, 2-phenyl-aminoethyl (meth)acrylate, glycidyl (meth)acrylate, or combinations thereof.

[0035] Suitable vinyl resins can be homopolymers or copolymers, which can be obtained by polymerizing one or more monomers including the following: vinyl aromatic compounds such as styrene and vinyltoluene; nitriles such as (meth)acrylonitrile; vinyl and vinylidene halides such as vinyl chloride and vinylidene fluoride; and vinyl esters such as vinyl acetate. Suitable vinyl resins that can be used include, but are not limited to, those sold under the trademark LUMIFLON TM Vinyl resins commercially available from AGC Chemicals Europe Limited (Amsterdam, Netherlands).

[0036] Suitable polysiloxane resins can include, but are not limited to, alkyl-substituted polysiloxanes, aryl polysiloxanes, their copolymers, their blends, and their mixtures. The alkyl substituents can be selected from short-chain alkyl groups having 1 to 4 carbon atoms such as methyl or propyl. The aryl substituents can include phenyl groups. Suitable polysiloxane resins that can be used include, but are not limited to 601 or M 50E (both are commercially available from Wacker Chemie AG (Munich, Germany)) and DOWSIL TM RSN-6018 (commercially available from The Dow Chemical Company (USA)).

[0037] Suitable epoxy resins can be prepared in a known manner, for example by reacting a compound containing at least one epoxy functional group with a cyclic co-reactant containing at least two hydroxyl groups. Examples of suitable compounds containing one epoxy functional group include, but are not limited to, glycidol; epichlorohydrin; glycidylamines and mixtures thereof. As used herein, the terms "epoxy resin" and "epoxide" are used interchangeably. Examples of suitable cyclic co-reactants containing at least two hydroxyl groups include, but are not limited to, bisphenol A; hydrated bisphenol A; bisphenol F; hydrated bisphenol F; novolac resins such as phenol novolac, cresol novolac; and mixtures thereof. Suitable epoxy resins that can be used include, but are not limited to, Eponex 1510, Eponex 1513, Epikote Resin 862 and Epikote Resin 828 commercially available from Hexion (USA), Epodil 757 commercially available from Evonik Corporation (Germany), Araldite GY 2600, Araldite GY 281 and Araldite EPN 1138 commercially available from Huntsman (USA).

[0038] Suitable polyamide resins can be prepared in a known manner, for example, by polymerizing polyamines and polyacids or by ring-opening polymerization of lactams. As used herein, the term "polyamine" refers to a compound having more than one amine group per molecule, such as a compound having 2, 3, 4, 5, 6 or more amine groups per molecule. Suitable polyamines include, but are not limited to: aliphatic diamines such as 1,2-ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,2-butanediamine, 1,3-butanediamine, 1,4-butanediamine, 1,3-pentanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 2-methyl-1,5-pentanediamine, 2,5-dimethylhexane-2,5-diamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine and 1,10-decanediamine; cycloaliphatic diamines such as 2,4'-diaminodicyclohexylmethane, 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane and 3,3'-diyl-4,4'-diaminodicyclohexylmethane; and aromatic diamines such as 1,2-benzenediamine, 1,3-benzenediamine, 1,4-benzenediamine, 1,5-naphthalenediamine, 1,8-naphthalenediamine, 2,4-toluenediamine, 2,5-toluenediamine, 2,6-toluenediamine and 3,3'-dimethyl-4,4'-biphenyldiamine. Non-limiting examples of suitable polyacids can include those polyacids listed above for the preparation of polyesters. Suitable lactams can include, but are not limited to, β-propiolactam; γ-butyrolactam; δ-valerolactam; ε-caprolactam; and mixtures thereof. Suitable polyamide resins that can be used include, but are not limited to, polyamide resins commercially available under the trademark Flex-Rez TM Commercially available polyamide resins such as Flex-Rez commercially available from Lawter (Chicago, Illinois, USA) TM 0080CS, Flex-Rez TM 1060CS, Flex-Rez TM 1074CS A.

[0039] As used herein, "hindered amine light stabilizer" refers to a compound containing an amine functional group that is added to a polymeric material to inhibit or retard their degradation by, for example, photooxidation. Typically, derivatives of tetramethylpiperidine are used. Examples of suitable hindered amine light stabilizers include, but are not limited to Light stabilizers such as those available from BASF (Ludwigshafen, Germany) 292, 123, 328, 622, 783 and 770.

[0040] As used herein, "UV light absorbers and stabilizers" refers to compounds that are used to absorb UV radiation to reduce UV degradation of polymeric materials. Examples of suitable UV light absorbers and stabilizers include, but are not limited to, CYASORB light stabilizers such as CYASORB UV-1164L available from Solvay (Houten, the Netherlands) and 1130.

[0041] The coating composition may contain a catalyst to promote any desired curing reaction. Any catalyst typically used to catalyze crosslinking reactions may be used, and there is no particular limitation on the catalyst. Non-limiting examples of catalysts include: phenyl acid phosphate; sulfonic acid functional catalysts such as dodecylbenzenesulfonic acid (DDBSA), dinonylnaphthalenesulfonic acid, dinonylnaphthalenedisulfonic acid, salts of the above sulfonic acids; complexes of organometallic compounds (including tin, zinc, zirconium, strontium or bismuth) such as stannous octoate, butyltin acid, dibutyltin dilaurate (DBTL), dibutyltin diacetate, mercaptodibutyltin, dibutyltin diacetate, dibutyltin dimaleate, dimethyltin diacetate, dimethyltin dilaurate, 1,4-diazabicyclo[2.2.2]octane and bismuth carboxylate, etc.; tertiary amines such as 1,8-diazabicyclo[5.4.0]undec-7-ene and triethylamine, etc.; or any combination of the foregoing catalysts.

[0042] Alternatively, the coating composition may be substantially free of a catalyst. As used throughout this specification, the term "substantially free of" refers to a composition containing an amount of the corresponding compound that is less than 0.5 wt%, such as 0.2 wt%, such as 0.1 wt%, based on the total weight of the coating composition. The coating composition may be completely free of a catalyst, i.e., the coating composition may contain 0 wt% of a catalyst.

[0043] As used herein, the term "corrosion inhibitor" refers to a component that reduces the corrosion rate or severity of the surface of a metal or metal alloy substrate treated with a composition containing the corrosion inhibitor, as compared to the surface of the same metal or metal alloy substrate treated with the same composition without the corrosion inhibitor under the same conditions.

[0044] As used herein, the term "adhesion promoter" refers to any material that, when included in a coating composition, enhances the adhesion of the coating composition compared to the same coating composition without the adhesion promoter. Suitable examples of adhesion promoters include, but are not limited to, free acids, phosphated epoxy resins, alkoxysilanes, or chlorinated or non-chlorinated polyolefins. As used herein, the term "free acid" is intended to cover organic and / or inorganic acids included as separate components of a composition, rather than any acid that may be used to form polymers that may be present in the composition. Free acids can include tannic acid, gallic acid, phosphoric acid, phosphorous acid, citric acid, malonic acid, boric acid, derivatives thereof, or mixtures thereof. Suitable derivatives include esters, amides, and / or metal complexes of such acids.

[0045] As used herein, "rheology modifier" refers to a component that modifies the flow behavior of a composition by increasing the viscosity of the composition it contacts compared to the same composition not in contact with the rheology modifier. Non-limiting examples of rheology modifiers include silica, chemically modified silica (e.g., fumed silica), alumina, chemically modified alumina (e.g., fumed alumina), hectorite clay (such as bentonite), hydrophobically modified ethylene oxide polymers, rubber latex (such as, for example, styrene-butadiene rubber particles dispersed in an aqueous liquid medium), cellulose derivatives, polyamide waxes, microgels, solvent-based polymeric associative thickeners (exemplified by BYK-410 commercially available from BYK-Chemie GmbH (Wesel, Germany)), or any combination thereof.

[0046] As used herein, the term "sag control agent" refers to a compound that minimizes sagging, which is a defect (such as teardrops) caused by the gravity-driven flow of a wet coating composition when applied to a substrate, particularly a substrate comprising non-horizontal (e.g., vertical) surfaces, compared to the same wet coating composition without the sag control agent. Suitable flow control agents, particularly sag control agents, can include, but are not limited to, those compounds described in US 4,311,622 A, EP 0 192 304 A1, and EP 3 728482A1.

[0047] Surfactants can optionally be added to the coating composition to aid in the flow and wetting of the substrate. Suitable surfactants include, but are not limited to, alkyl sulfates (e.g., sodium dodecyl sulfate); ether sulfates; phosphate esters; sulfonates; and their various base salts, ammonium salts, and amine salts; fatty alcohol ethoxylates; alkylphenol ethoxylates (e.g., nonylphenol polyethers); salts and / or combinations thereof.

[0048] As used herein, "abrasion-resistant particles" are particles that, when used in a coating, will impart a certain level of abrasion resistance to the coating compared to the same coating without the particles. The abrasion-resistant particles can have a hardness value greater than the hardness value of the material capable of abrading the coating. Examples of materials capable of abrading the coating can include, but are not limited to, dirt, sand, rock, glass, and car wash brushes. The hardness values of the abrasion-resistant particles and the material capable of abrading the coating can be determined by any conventional hardness measurement method (such as Vickers hardness or Brinell hardness), or can be determined according to the original Mohs hardness scale, which represents the relative scratch resistance of the material surface on a scale of one to ten. The abrasion-resistant particles can have a Mohs hardness value greater than 5, such as greater than 6, and can have a Mohs hardness value of at least 9, such as 10. Suitable abrasion-resistant particles include organic and / or inorganic particles. Examples of suitable particles include, but are not limited to, diamond particles (such as diamond powder particles) and particles formed from carbide materials (such as titanium carbide, silicon carbide, and boron carbide), silica, alumina, aluminum silicate, silica alumina, alkali metal aluminosilicate, borosilicate glass, nitrides including boron nitride and silicon nitride, titanium dioxide, zirconium oxide, zinc oxide, quartz, nepheline syenite, baddeleyite, and orthoclase.

[0049] As used herein, the term "colorant" means any substance that imparts color and / or other opacity and / or other visual effects to a composition. The term "colorant" includes, for example, pigments and dyes. The colorant can be added to the coating composition in any suitable form (such as discrete particles, dispersions, solutions, and / or flakes). Suitable dyes include, but are not limited to, acid dyes, azo dyes, basic dyes, direct dyes, disperse dyes, reactive dyes, solvent dyes, sulfur dyes, mordant dyes, for example, bismuth vanadate, anthraquinone, perylene, aluminum, quinacridone, thiazole, thiazine, azo, indigo-based, nitro, nitroso, oxazine, phthalocyanine, quinoline, stilbene, and triphenylmethane. Examples of suitable pigments include, but are not limited to, carbazole dioxazine pigments, azo pigments, monoazo pigments, diazo pigments, naphthol AS pigments, salt type (lake) pigments, benzimidazolone pigments, metal complex pigments, isoindolinone pigments, isoindoline pigments, polycyclic phthalocyanine pigments, quinacridone pigments, perylene pigments, violanthrone pigments, diketopyrrolopyrrole pigments, thioindigo pigments, anthraquinone pigments, indanone pigments, anthrapyrimidine pigments, flavanone pigments, pyrone pigments, anthrone pigments, dioxazine pigments, triarylcarbonium pigments, quinophthalone pigments, diketopyrrolopyrrole red ("DPPBO red"), titanium dioxide, carbon black, and mixtures thereof. As used herein, the term "effect pigment" relates to pigments that impart a visual effect to a composition or a cured coating. Suitable effect pigments can include, but are not limited to, metallic effect pigments and pearlescent pigments, such as mica, aluminum oxide flakes, glass flakes, or mixtures thereof.

[0050] Suitable examples of antioxidants for, for example, preventing oxidation of resins due to thermal exposure during production and application or preventing yellowing of coatings include, but are not limited to, phenolic antioxidants and phosphite antioxidants, etc. Suitable antioxidants that can be used include, but are not limited to antioxidants such as Irganox 245, Irganox 1010, and Irganox 1076, which are commercially available from BASF SE (Ludwigshafen, Germany).

[0051] As used herein, "reactive diluent" refers to a monomer or oligomer that reduces the viscosity of a coating composition and can copolymerize during the curing of the coating composition. Suitable reactive diluents can have a molecular weight in the range of 100 g / mol to 350 g / mol. Suitable examples of reactive diluents include, but are not limited to, epoxy-functional compounds, vinyl-functional compounds, (meth)acrylate compounds, and combinations thereof.

[0052] As used herein, the term "plasticizer" refers to a component that enhances the flexibility of a resin and reduces the brittleness of the resin. Suitable plasticizers include, but are not limited to, phthalates such as dibutyl phthalate, butyl benzyl phthalate, diisooctyl phthalate, and decyl butyl phthalate; chlorinated paraffins; and hydrogenated terphenyls.

[0053] As used herein, "leveling agent" refers to a compound that enhances the thickness uniformity of a cured coating. Suitable leveling agents that can be used include, but are not limited to, BYK-320 or BYK-306, which are commercially available from BYK Chemie GmbH (Wesel, Germany).

[0054] Suitable fillers include, but are not limited to, silica, barium sulfate, talc, calcium carbonate, and magnesium silicate.

[0055] As used herein, the term "matting agent" refers to a compound that reduces the gloss of a cured coating compared to the same coating without the matting agent. Suitable matting agents that can be used include, but are not limited to, OK 412, which is commercially available from Evonik Industries AG (Essen, Germany), or TS100. TS100.

[0056] As used herein, the term "solvent-based coating composition" refers to a composition that comprises one or more organic solvents as the major component of the liquid carrier and less than 50 wt%, such as less than 40 wt%, such as less than 30 wt%, such as less than 20 wt%, such as less than 10 wt%, such as less than 5 wt%, such as less than 2 wt%, such as less than 1 wt% water based on the total weight of the liquid carrier (i.e., the combination of organic solvents and water, if present). The solvent-based coating composition can be substantially free of water, i.e., the solvent-based coating composition can comprise less than 0.5 wt%, such as less than 0.2 wt%, such as less than 0.1 wt% water based on the total weight of the liquid carrier. The solvent-based coating composition can be completely free of water, i.e., the solvent-based coating composition can comprise 0 wt% water based on the total weight of the liquid carrier.

[0057] The organic solvents can include any suitable organic solvents known in the art. Non-limiting examples of suitable organic solvents can include, but are not limited to, acetates, esters, and ketones, aliphatic and / or aromatic hydrocarbons or mixtures thereof. Typically, the organic solvents of the first component and / or the second component can each independently include aromatic solvents, alkyl acetate solvents, aliphatic solvents, ketone solvents or combinations thereof; such as aromatic solvents, alkyl acetate solvents or combinations thereof. As used herein, "aromatic solvent" refers to a solvent containing aromatic hydrocarbons, such as naphtha, toluene or xylene. As used herein, the term "alkyl acetate solvent" refers to a solvent having an acetate group attached to an alkyl chain, such as ethyl acetate. Suitable organic solvents can include, for example, hexane, heptane, octane, toluene, xylene, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, 2-butoxyethyl acetate, amyl acetate, isoamyl acetate, and acetone, etc.

[0058] The first solvent-based component and / or the second solvent-based component can be substantially free of water, alcohols and / or ether solvents, i.e., the first solvent-based component and / or the second solvent-based component can comprise less than 5.0 wt%, such as less than 3.0 wt%, such as less than 2.0 wt%, such as less than 1.0 wt% water, alcohols and / or ether solvents based on the total weight of the liquid carrier. The first solvent-based component and / or the second solvent-based component can be substantially free of water, alcohols and / or ether solvents, i.e., the first solvent-based component and / or the second solvent-based component can comprise less than 0.5 wt%, such as less than 0.2 wt%, such as less than 0.1 wt% water, alcohols and / or ether solvents based on the total weight of the liquid carrier.

[0059] The first solvent-based component and / or the second solvent-based component may be substantially free of water, i.e., the first solvent-based component and / or the second solvent-based component may contain less than 5.0 wt.-%, such as less than 3.0 wt.%, such as less than 2.0 wt.%, such as less than 1.0 wt.% of water based on the total weight of the liquid carrier. The first solvent-based component and / or the second solvent-based component may be substantially free of water, i.e., the first solvent-based component and / or the second solvent-based component may contain less than 0.5 wt.-%, such as less than 0.2 wt.%, such as less than 0.1 wt.% of water based on the total weight of the liquid carrier.

[0060] The first solvent-based component and / or the second solvent-based component may be substantially free of alcohol solvents, i.e., the first and / or second solvent-based component may contain less than 5.0 wt.-%, such as less than 3.0 wt.%, such as less than 2.0 wt.%, such as less than 1.0 wt.% of alcohol solvents based on the total weight of the liquid carrier. The first solvent-based component and / or the second solvent-based component may be substantially free of alcohol solvents, i.e., the first solvent-based component and / or the second solvent-based component may contain less than 0.5 wt.-%, such as less than 0.2 wt.%, such as less than 0.1 wt.% of alcohol solvents based on the total weight of the liquid carrier.

[0061] The first solvent-based component and / or the second solvent-based component may be substantially free of ether solvents, i.e., the first solvent-based component and / or the second solvent-based component may contain less than 5.0 wt.-%, such as less than 3.0 wt.%, such as less than 2.0 wt.%, for example less than 1.0 wt.% of ether solvents based on the total weight of the liquid carrier. The first solvent-based component and / or the second solvent-based component may be substantially free of ether solvents, i.e., the first solvent-based component and / or the second solvent-based component may contain less than 0.5 wt.-%, such as less than 0.2 wt.%, such as less than 0.1 wt.% of ether solvents based on the total weight of the liquid carrier.

[0062] The present disclosure further relates to a solvent-based composition comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group and at least one solvent selected from aromatic, alkyl acetates or combinations thereof. Herein, the polyisocyanate refers to the water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group as described above. The solvent-based composition can be used as the second component in the above multi-component coating composition.

[0063] As described above, the solvent-based composition may further comprise a second polyisocyanate that does not have a sulfonic acid group and / or a phosphoric acid ester ether group. The second polyisocyanate may be an aliphatic polyisocyanate.

[0064] In a solvent-based composition, when a second polyisocyanate that has neither a sulfonic acid group nor a phosphoric acid ester ether group is additionally used, the water-dispersible polyisocyanate and the second polyisocyanate can be used in a weight ratio within the range of 1:10 to 10:1, or 5:1 to 1:5, or 3:1 to 1:3, or 2:1 to 1:2. For example, the water-dispersible polyisocyanate and the second polyisocyanate can be used in a weight ratio of 1:1.

[0065] Based on the total weight of the resin solids in the solvent-based composition, the polyisocyanate can be present in the solvent-based composition in an amount of at least 30% by weight, such as at least 40% by weight, such as at least 50% by weight, such as at least 60% by weight, such as at least 70% by weight, such as at least 80% by weight. Based on the total weight of the resin solids in the solvent-based composition, the polyisocyanate can be present in the second solvent-based component in an amount not exceeding 90% by weight, such as not exceeding 85% by weight, such as not exceeding 80% by weight. Based on the total weight of the resin solids in the solvent-based composition, the range of the polyisocyanate can include, for example, 30% by weight to 90% by weight, such as 30% by weight to 85% by weight, such as 30% by weight to 80% by weight, such as 40% by weight to 90% by weight, such as 50% by weight to 90% by weight, such as 60% by weight to 90% by weight, such as 70% by weight to 90% by weight, such as 80% by weight to 90% by weight. Based on the total weight of the resin solids in the solvent-based composition, the polyisocyanate can be present in the solvent-based composition in a range between any of the above values, such as 40% by weight to 85% by weight, such as 50% by weight to 85% by weight, such as 60% by weight to 80% by weight, such as 70% by weight to 85% by weight.

[0066] The solvent-based composition can be substantially free of water, alcohols, and / or ether solvents, that is, the solvent-based composition can contain less than 5.0% by weight, such as less than 3.0% by weight, such as less than 2.0% by weight, such as less than 1.0% by weight of water, alcohols, and / or ether solvents. The solvent-based composition can be substantially free of water, alcohols, and / or ether solvents, that is, the solvent-based composition can contain less than 0.5% by weight, such as less than 0.2% by weight, such as less than 0.1% by weight of water, alcohols, and / or ether solvents.

[0067] The solvent-based composition can be substantially free of water, that is, the solvent-based composition can contain less than 5.0% by weight, such as less than 3.0% by weight, such as less than 2.0% by weight, such as less than 1.0% by weight of water. The solvent-based composition can be substantially free of water, that is, the solvent-based composition can contain less than 0.5% by weight, such as less than 0.2% by weight, such as less than 0.1% by weight of water.

[0068] The solvent-based composition can be substantially free of alcohol solvents, i.e., the solvent-based composition can contain less than 5.0 wt%, such as less than 3.0 wt%, such as less than 2.0 wt%, such as less than 1.0 wt% of alcohol solvents. The solvent-based composition can be substantially free of alcohol solvents, i.e., the solvent-based composition can contain less than 0.5 wt%, such as less than 0.2 wt%, such as less than 0.1 wt% of alcohol solvents.

[0069] The solvent-based composition can be substantially free of ether solvents, i.e., the solvent-based composition can contain less than 5.0 wt%, such as less than 3.0 wt%, such as less than 2.0 wt%, such as less than 1.0 wt% of ether solvents. The solvent-based composition can be substantially free of ether solvents, i.e., the solvent-based composition can contain less than 0.5 wt%, such as less than 0.2 wt%, such as less than 0.1 wt% of ether solvents.

[0070] The present disclosure further relates to a method of coating a substrate. The method includes applying a composition to at least a portion of the surface of the substrate to form a coating layer, the composition comprising: a first solvent-based component comprising a polyfunctional compound containing active hydrogen; and a second solvent-based component comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group.

[0071] According to the present disclosure, the method can further include curing the coating layer.

[0072] The multi-component coating composition used in the disclosed method can be any of the above multi-component coating compositions.

[0073] According to the disclosed method, the coating composition can be applied to at least a portion of the surface of the substrate by any standard method in the art (such as by brushing, spraying, dipping, printing, flow coating, etc.). Spraying can be accomplished by compressed air spraying or electrostatic spraying. The coating composition can be applied to at least a portion of the surface of the substrate to obtain a dry coating thickness of at least 20 μm or at least 30 μm or at least 40 μm or at least 50 μm. The coating composition can be applied to at least a portion of the surface of the substrate to obtain a dry coating thickness of 150 μm or less, such as 130 μm or less or 100 μm or less or 80 μm or less. The coating composition can be applied to at least a portion of the surface of the substrate to obtain a dry coating thickness within the range between any of the above values, for example, 20 μm to 150 μm, such as 30 μm to 130 μm, such as 40 μm to 100 μm, such as 50 μm to 80 μm. The thickness can be measured according to DIN EN ISO 2178:2016. As used herein, "dry coating thickness" is the thickness of the coating applied to at least a portion of the surface of the substrate, measured above the substrate after the coating has cured.

[0074] The coating composition can be cured by thermal curing. Thermal curing refers to exposing the coating composition to a temperature above room temperature to achieve at least partial curing of the coating composition. The temperature for thermally curing the coating composition can be at least 60 °C, such as at least 70 °C, such as at least 80 °C, such as at least 90 °C, such as at least 100 °C, such as at least 110 °C, such as at least 120 °C. The curing temperature can be 160 °C or lower, such as 150 °C or lower, such as 140 °C or lower, such as 130 °C or lower. The temperature for curing the coating composition can be from 60 °C to 160 °C, such as from 60 °C to 150 °C, such as from 60 °C to 140 °C, such as from 60 °C to 130 °C, such as from 70 °C to 160 °C, such as from 70 °C to 150 °C, such as from 70 °C to 140 °C, such as from 70 °C to 130 °C, such as from 80 °C to 160 °C, such as from 80 °C to 150 °C, such as from 80 °C to 140 °C, such as from 80 °C to 130 °C, such as from 90 °C to 160 °C, such as from 90 °C to 150 °C, such as from 90 °C to 140 °C, such as from 90 °C to 130 °C, such as from 100 °C to 160 °C, such as from 100 °C to 150 °C, such as from 100 °C to 140 °C, such as from 100 °C to 130 °C, such as from 110 °C to 160 °C, such as from 110 °C to 150 °C, such as from 110 °C to 140 °C, such as from 110 °C to 130 °C, such as from 120 °C to 160 °C, such as from 120 °C to 150 °C, such as from 120 °C to 140 °C, such as from 120 °C to 130 °C. The coating composition can be cured for at least 2 minutes, such as at least 5 minutes, such as at least 10 minutes, such as at least 15 minutes, such as at least 20 minutes, such as 45 minutes or less, such as 40 minutes or less, such as 35 minutes or less, such as 25 minutes or less, such as 20 minutes or less. The time for curing the coating composition can be within the range between any of the above values, such as from 2 minutes to 45 minutes, such as from 5 minutes to 40 minutes, such as from 10 minutes to 35 minutes, such as from 15 minutes to 30 minutes, such as from 20 minutes to 25 minutes.

[0075] As used herein, the terms "cured", "curing", or similar terms when used in connection with the coating compositions described herein mean that at least a portion of the components of the coating composition are crosslinked to form a coating.

[0076] The coating composition can be applied to a variety of substrates. For example, the substrate (particularly a portion of the surface of the substrate to which the coating composition is applied) can comprise at least one material selected from the following: metals, plastics, ceramics (such as boron carbide or silicon carbide), glass, wood, paper, cardboard, rubber, leather, textiles, glass fiber composites, carbon fiber composites, existing coatings, or mixtures thereof.

[0077] The metal may include, but is not limited to, ferrous metals, tin steel, aluminum, aluminum alloys, zinc aluminum alloys, titanium, titanium alloys, magnesium, magnesium alloys, copper, copper alloys, and mixtures. Ferrous metals may include iron, steel, and their alloys. Non-limiting examples of useful steel materials may include rolled steel, galvanized (zinc-coated) steel, electrogalvanized steel, stainless steel, pickled steel, zinc-iron alloys, and combinations thereof. Combinations of ferrous metals and non-ferrous metals may also be used. Aluminum alloys of the 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, or 8XXX series, as well as clad aluminum alloys and cast aluminum alloys of the A356, 1XX.X, 2XX.X, 3XX.X, 4XX.X, 5XX.X, 6XX.X, 7XX.X, or 8XX.X series may also be used as substrates. Magnesium alloys of the AZ31B, AZ91C, AM60B, or EV31A series may also be used as substrates. The substrate may be pretreated with a pretreatment solution that includes a zinc phosphate pretreatment solution (such as those described in US 4,793,897 and US 5,588,989) or a zirconium-containing pretreatment solution (such as those described in US 7,749,368 and US 8,673,091).

[0078] The plastic may include, but is not limited to, polyethylene terephthalate (PET), polyethylene (PE) (such as high-density polyethylene (HDPE) or low-density polyethylene (LDPE)), polyvinyl chloride (PVC), polypropylene (PP), polycarbonate (PC), polyurethane (PUR), polystyrene (PS), and their blends, composites, or mixtures.

[0079] As used herein, the term "multicomponent coating composition" refers to a composition that contains more than one component (such as two or more components). As used herein, a "two-component" or "2K" coating composition is a composition that, when mixed, at least a portion of the reactive components readily react and at least partially cure without activation by an external energy source, such as at ambient temperature (e.g., a temperature in the range of 20 °C to 25 °C) or a slightly elevated temperature (e.g., a temperature in the range of 25 °C to 60 °C). Those skilled in the art will understand that the two components of the coating composition are stored separately and mixed prior to application of the coating composition.

[0080] The coating composition may be an undercoat composition and / or a primer composition and / or a topcoat composition. Additionally, the coating composition may be a clearcoat composition and / or a colored paint composition. The coating composition may be a 2K clearcoat composition.

[0081] The present disclosure further relates to a substrate comprising a cured coating layer obtained from the foregoing multi-component coating composition. The coated substrate may be selected from vehicles, storage tanks, windmills, packaging substrates, wooden floors and furniture, clothing, electronic products, glass and transparencies, sports equipment, buildings and bridges, etc. or parts thereof. For example, the coated substrate may be a vehicle component. The cured coating layer on the substrate may be applied by the above method.

[0082] The term "vehicle" is used in its broadest sense and includes (but is not limited to) all types of aircraft, spacecraft, watercraft, and land vehicles. For example, the vehicle may include aircraft (such as airplanes), including private airplanes and small, medium, or large commercial airliners, freight airplanes, and military airplanes; helicopters, including private, commercial, and military helicopters; aerospace vehicles, including rockets and other spacecraft. The vehicle may include land vehicles such as, for example, trailers, cars, trucks, buses, coaches, vans, ambulances, fire trucks, recreational vehicles, travel trailers, go-karts, carriages, forklifts, sit-on lawnmowers, agricultural vehicles (such as tractors and harvesters), construction vehicles (such as excavators, bulldozers, and cranes), golf carts, motorcycles, bicycles, trains, and trams. The vehicle also includes watercraft such as, for example, ships, submarines, boats, jet skis, and hovercraft.

[0083] The present disclosure further relates to the use of a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group as a curing agent in a solvent-based coating composition for the following: improving the chemical resistance, scratch resistance, abrasion resistance, and / or appearance of the coating obtained from the coating composition as compared to the coating obtained from the same coating composition cured with a polyisocyanate having neither a sulfonic acid group nor a phosphoric acid ester ether group.

[0084] As used herein, the terms "scratch resistance" and "abrasion resistance" refer to the resistance of a material to damage by impact, friction, or wear that results in visible scratches or wear. Scratch resistance and abrasion resistance can be determined according to DIN EN ISO20566:2021 and DIN ENISO 21546:2021, respectively. As used herein, the term "chemical resistance" refers to the tolerance of a material to the effects of chemicals, such as, for example, discoloration, change in gloss, softening, swelling, coating detachment, or blistering. Chemical tolerance against at least one or a combination of acids, enzymes, and saps can be determined according to DIN EN ISO 2812-5:2018.

[0085] In addition, compared to coatings obtained from the same coating composition cured with a polyisocyanate that has neither a sulfonic acid group nor a phosphoric acid ester ether group, the appearance of the coatings obtained from the disclosed coating compositions is enhanced. Improved appearance characteristics are, for example, reduced surface waviness and higher coating gloss.

[0086] Surface waviness is an indication of surface roughness and can be measured using a wave scanning instrument, such as the BYK Wave-scan Dual instrument available from BYK Gardner USA (which measures surface topography by optical profilometry). The wave scanning instrument uses a point source (i.e., a laser) to illuminate the surface at an incident angle of 60° at a predetermined distance (e.g., 10 cm). The reflected light is measured at the same but opposite angle. When the light beam hits a "peak" or "valley" of the surface, a maximum signal is detected. When the light beam hits the "slope" of the peak / valley, a minimum signal is detected. The measured signal frequency is equal to twice the spatial frequency of the coating surface topography. Surface "waviness" is divided into long-term waviness and short-term waviness ("long waves" and "short waves") to simulate visual assessment by the human eye. A mathematical filter function is used to divide the data into long-wave (structural size > 0.6 mm) and short-wave (structural size < 0.6 mm) signals. Each value ranges from 0 to 50. Long-term waviness represents the variance of the long-wave signal amplitude, while short-term waviness represents the variance of the short-wave signal amplitude. The long-term and short-term waviness of the coating surface can indirectly measure topographical influencing factors, such as substrate roughness, the fluidity and leveling properties of the coating. The long-wave value and the short-wave value can be determined using the BYK Wave-scan Dual instrument from BYK Gardner in Maryland, USA, according to the operating method recommended by the manufacturer. Smaller magnitudes of the long-wave value and the short-wave value indicate a smoother coating appearance.

[0087] As used herein, the term "gloss" refers to the surface gloss of the coating and is related to the amount of light reflected at a specular reflection angle of 20°. The gloss value can be measured using the BYK Wave-scan Dual instrument according to the operating method recommended by the manufacturer. Gloss can be determined according to DIN EN ISO 2813:2015-02.

[0088] As used herein, unless otherwise expressly specified, all numbers, such as those representing values, ranges, amounts, or percentages, may be read as if preceded by the word "about", even if the term does not explicitly appear.

[0089] The following examples are intended to illustrate the disclosure and should not be construed as limiting in any way.

[0090] Example

[0091] Preparation of a two-component (2K) coating composition

[0092] The 2K clearcoat coating composition is prepared by separately mixing Component A and Component B.1, B.2 or B.3, as listed in Table 1.

[0093] Table 1: 2K coating composition

[0094] Component A Per weight part [%] <![CDATA[Acrylic resin 1 > 35.9 <![CDATA[Polyester resin 2 > 2.75 <![CDATA[Melamine resin 3 > 4.22 <![CDATA[Ultraviolet absorber 4 > 4.31 <![CDATA[Hindered amine light stabilizer 5 > 0.59 <![CDATA[Flow control agent 6 > 0.01 <![CDATA[Defoamer 7 > 0.04 <![CDATA[Catalyst 8 > 0.9 <![CDATA[ sag control agent 9 > 22.60 <![CDATA[Solvent 10 > 28.68 Component B.1 (comparative) <![CDATA[Polyisocyanate 11 > 78.00 <![CDATA[Solvent 12 > 22.00 Component B.2 (hydrophilic) <![CDATA[Polyisocyanate 13 > 39.70 <![CDATA[Polyisocyanate 11 > 39.00 <![CDATA[Solvent 12 > 21.30 Component B.3 (hydrophilic) <![CDATA[Polyisocyanate 14 > 39.50 <![CDATA[Polyisocyanate 11 > 39.00 <![CDATA[Solvent 12 > 22.00

[0095] 1 : The solids content of the acrylic polyol as a dispersion in solvent naphtha / butyl acetate is 65%, hydroxyl value [mg KOH / g]: 150, acid value [mg KOH / g]: 3.2–6.0, Tg [°C]: 60, and viscosity (23 °C, 100 s -1 ) [Pa·s]: 3.3–6.5.

[0096] 2 : The solids content of the OH-functional polyester in butyl acetate solution is 70%, hydroxyl value [mg KOH / g]: 280, acid value [mgKOH / g]: 85, Tg [°C]: 18, and viscosity (23 °C, 1000 s -1 ) [Pa·s]: 4.4.

[0097] 3 : The minimum solids content of the highly butylated melamine resin is 96%, free formaldehyde <0.1%, viscosity (25 °C) [Pa·s]: 2.8–5.6, equivalent weight (g / eq): 200 - 300.

[0098] 4 : Tinuvin 928, commercially available from BASF (Germany).

[0099] 5 : Tinuvin 123, commercially available from BASF (Germany).

[0100] 6 : Polyether-modified polydimethylsiloxane.

[0101] 7 : Xylene solution of polyacrylate.

[0102] 8 : Amine-neutralized dodecylbenzenesulfonic acid contains approximately 40% active acid in isopropanol and has an acid value [mg KOH / g] of 69–79.

[0103] 9 : Setalux 91767VX-60, commercially available from Axalta (Germany).

[0104] 10 : A mixture of isopentyl acetate, Aromatic 100 commercially available from ExxonMobil Corporation (Irving, Texas, USA), butyl acetate, ethyl 3-ethoxypropionate, diethylene glycol butyl ether acetate, and 2-butoxyethyl acetate, with a mixing ratio of approximately 42:0.5:13:13:4.5:27.

[0105] 11 : NCO content [%] of HMDI trimer: 21.8, viscosity (23 °C) [Pa·s]: 2.25–3.75, density (20 °C) [g / cm 3 : 1.16.

[0106] 12 : Butyl acetate

[0107] 13 : HMDI trimer with a phosphate ester ether group, and NCO content [%]: 20.7–22.7, viscosity (25 °C) [Pa·s]: 1.1–1.9, density (25 °C) [g / cm 3 : 1.17.

[0108] 14 : HMDI trimer with a sulfonic acid group, NCO content [%]: 21.0 - 22.0, viscosity (25 °C) [Pa·s]: 1.5 - 3.5, density (25 °C) [g / cm 3 : 1.16.

[0109] The hydroxyl value is determined according to DIN EN ISO 4629-1:2016. The glass transition temperature (Tg) is determined according to DIN EN ISO168025:2005. The acid value is determined according to ISO 2114:2002. The viscosity is determined according to DIN ENISO 3219-1:2021. The free formaldehyde content is determined according to DIN EN ISO 11402:2005-09. The NCO content is determined according to DIN EN ISO 11909:2007-05. The solid content is determined according to DIN EN 3251:2019. The density is determined according to DIN EN ISO 2811.

[0110] Coating of the substrate

[0111] The coating composition obtained by mixing component A with component B.1, B.2 or B.3 separately (mixing ratio = 100:36 / weight) was sprayed onto an E-coated steel substrate available from ACT Test Panels LLC (Hillsdale, Michigan, USA) using an electrostatic spray booth from Dürr AG (Stuttgart, Germany). The dry film thickness of the coating composition measured according to DIN EN ISO 2178:2016 was 40 μm to 50 μm.

[0112] The coated substrate was cured using an oven

[0113] The substrate coated with the coating composition shown in Table 1 was cured in an oven (HORO Dr. Hoffmann GmbH & Co. KG (Ostfildern, Germany)) using hot air at 140 °C for 30 minutes.

[0114] Measurement of the properties of the cured coating

[0115] The properties of the cured coating were measured. The scratch resistance of the cured coating simulating a car wash system was measured by residual gloss according to DIN EN ISO 20566:2021. The chemical resistance to sap, surface waviness and gloss were measured as described above.

[0116] Table 2: Properties of the cured coating composition

[0117]

[0118] As can be seen from Table 2, enhanced chemical resistance, scratch resistance and abrasion resistance can be achieved by using a water-dispersible polyisocyanate having a sulfonic acid group (Composition 3) or a phosphoester ether group (Composition 2). Furthermore, it was surprisingly found that the appearance of the cured coatings containing these polyisocyanates was also improved compared to coating compositions without a water-dispersible polyisocyanate having a sulfonic acid or phosphoester ether group. This is particularly surprising since appearance and resistance often have a countercurrent effect. However, the long-wave and short-wave values of the compositions according to the present disclosure are at least comparable or even lower compared to the compositions without a water-dispersible polyisocyanate having a sulfonic acid group or a phosphoester ether group (Comparative Composition 1). Lower long-wave and short-wave values are generally considered to be more aesthetically pleasing and desirable in coating compositions. The coating compositions according to the present disclosure further show improved gloss values.

Claims

1. A multi-component coating composition, comprising: A first solvent-based component comprising a polyfunctional compound containing active hydrogen; and a second solvent-based component comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group.

2. The composition according to claim 1, wherein the polyfunctional compound containing active hydrogen is selected from the group consisting of polyols, polyamines, polythiols, and mixtures thereof.

3. The composition according to claim 1 or 2, wherein the polyfunctional compound containing active hydrogen comprises a polyol or is a polyol.

4. The composition according to claim 2 or 3, wherein the polyol comprises a (meth)acrylic polyol, a polyester polyol, or a combination thereof.

5. The composition according to any one of claims 2 to 4, wherein the polyol is present in the first component in an amount of 30% to 99.8% by weight based on the total weight of the resin solids in the first solvent-based component.

6. The composition according to any one of the preceding claims, wherein the first solvent-based component further comprises a melamine-based compound.

7. The composition according to claim 6, wherein the first solvent-based component comprises the melamine-based compound in an amount of 0.2% to 30% by weight based on the total weight of the resin solids in the first solvent-based component.

8. The composition according to any one of the preceding claims, wherein the first solvent-based component and / or the second solvent-based component further comprises one or more compounds selected from the group consisting of: additional polymers different from the polyfunctional compound containing active hydrogen, hindered amine light stabilizers, ultraviolet light stabilizers, ultraviolet light absorbers, curing catalysts, corrosion inhibitors, adhesion promoters, rheology modifiers, leveling agents, sag control agents, surfactants, fillers, matting agents, wear-resistant particles, colorants, antioxidants, reactive diluents, plasticizers, effect pigments, and combinations thereof.

9. The composition according to any one of the preceding claims, wherein the water-dispersible polyisocyanate is prepared from an aliphatic diisocyanate.

10. The composition according to any one of the preceding claims, wherein the water-dispersible polyisocyanate has an NCO content on solids in the range of 8% to 25% as determined according to DIN EN ISO 11 909:2007-05.

11. The composition according to any one of the preceding claims, wherein the second solvent-based component further comprises a second polyisocyanate having neither a sulfonic acid group nor a phosphoric acid ester ether group.

12. The composition according to claim 11, wherein the second polyisocyanate is an aliphatic polyisocyanate.

13. The composition according to claim 11 or 12, wherein the water-dispersible polyisocyanate and the second polyisocyanate are used in a weight ratio in the range of 1:10 to 10:1 or 5:1 to 1:5 or 3:1 to 1:3 or 2:1 to 1:2, or 1:

1.

14. The composition according to any one of the preceding claims, wherein the polyisocyanate is present in an amount of 30% to 90% by weight based on the total weight of the resin solids in the second solvent-based component.

15. The composition according to any one of the preceding claims, comprising 50% to 90% by weight of the first component and 10% to 50% by weight of the second component based on the total weight of the combined resin solids of the first and second components.

16. The composition according to any one of the preceding claims, wherein the solvents of the first solvent-based component and / or the second solvent-based component each independently comprise an aromatic solvent, an alkyl acetate solvent, an aliphatic solvent, a ketone solvent, or a combination thereof.

17. The composition according to any one of the preceding claims, wherein the first component and / or the second component each independently is substantially free of water, an alcohol solvent, and / or an ether solvent.

18. The composition according to any one of the preceding claims, wherein the composition is a two-component transparent coating composition.

19. A solvent-based composition comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group and at least one solvent selected from the group consisting of aromatics, alkyl acetates, or a combination thereof.

20. The composition according to claim 19, wherein the water-dispersible polyisocyanate is prepared from an aliphatic diisocyanate.

21. The composition according to claim 19 or 20, wherein the water-dispersible polyisocyanate has an NCO content on solids in the range of 8% to 25% as determined according to DIN EN ISO 11909:2007-05.

22. The composition according to any one of claims 19 to 21, further comprising a second polyisocyanate having neither a sulfonic acid group nor a phosphoric acid ester ether group.

23. The composition according to claim 22, wherein the second polyisocyanate is an aliphatic polyisocyanate.

24. The composition according to claim 22 or 23, wherein the water-dispersible polyisocyanate and the second polyisocyanate are used in a weight ratio in the range of 1:10 to 10:1, or 5:1 to 1:5, or 3:1 to 1:3, or 2:1 to 1:2, or 1:

1.

25. The composition according to any one of claims 19 to 24, wherein the polyisocyanate is present in an amount of 30% to 90% by weight based on the total weight of the resin solids in the composition.

26. The composition according to any one of claims 19 to 25, wherein the composition is substantially free of water, alcohol solvents, and / or ether solvents.

27. A method of coating a substrate, the method comprising: A coating composition is applied to at least a part of the surface of a substrate to form a coating layer, and the coating composition comprises: a first solvent-based component, the first solvent-based component comprising a polyfunctional compound containing active hydrogen; and a second solvent-based component, the second solvent-based component comprising a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group with each other.

28. The method according to claim 27, wherein the coating composition is a multi-component coating composition according to any one of claims 1 to 18.

29. The method according to claim 27 or 28, wherein one or more methods selected from brushing, spraying, dipping, printing, and flow coating are used to apply the coating composition to at least a portion of the surface of the substrate.

30. The method according to claim 29, wherein the composition is applied to at least a portion of the substrate by spraying, and wherein the spraying is accomplished by a method selected from the group consisting of compressed air spraying and electrostatic spraying.

31. A substrate comprising a cured coating layer obtained from a multi-component coating composition according to any one of claims 1 to 18.

32. The substrate according to claim 31, wherein the cured coating layer is applied to at least a portion of the surface of the substrate by a method according to any one of claims 27 to 30.

33. Use of a water-dispersible polyisocyanate having a sulfonic acid group and / or a phosphoric acid ester ether group as a curing agent in a solvent-based coating composition for the following purposes: improving the chemical resistance, appearance, scratch resistance, and / or abrasion resistance of the coating obtained from the coating composition as compared to a coating obtained from the same coating composition cured with a polyisocyanate having neither a sulfonic acid group nor a phosphoric acid ester ether group.

Images