Catalyst composition and coating compositions comprising the same

Abstract

A catalyst composition comprises a bismuth catalyst, a zinc catalyst, and a phosphorus-containing additive. The phosphorus-containing additive can be selected from (i) orthophosphoric acid, (ii) alkyl phosphonic acids, (iii) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; (iv) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; and (v) mixtures thereof. A coating composition comprises a polyol, an isocyanate compound, and the catalyst composition described above.

Description

CATALYST COMPOSITION AND COATING COMPOSITIONS COMPRISING THE SAMETECHNICAL FIELD

[0001] This application and the subject matter described herein relate to compositions for catalyzing the reaction between a polyol and an isocyanate compound and to two-component coating compositions (e.g., 2K polyurethane coatings) containing such catalyst compositions.BACKGROUND OF THE INVENTION

[0002] Two-component coating compositions (“2K coatings”) are used in a variety of applications due to their durability, chemical resistance, fast cure times, superior adhesion, and flexibility to meet specific application requirements. For example, polyurethane-based 2K coatings (“2K polyurethane coatings” or “2K poly coatings”) are used as protective coatings in a variety of applications. These 2K poly coating compositions are made with a first component containing a polyol (e.g., a resin comprising two or more hydroxy groups) and second component containing an isocyanate compound comprising at least two isocyanate groups. While the polyol and the isocyanate will react when the two components are mixed, a 2K poly coating composition typically contains a catalyst to accelerate the reaction and speed up the curing of the coating. However, catalyzing the reaction between the polyol and isocyanate can make it more difficult to work with the coating composition. For example, catalyzing the reaction can shorten the pot life of the coating composition.

[0003] The pot life measures how quickly the viscosity of the coating composition increases, with the pot life generally being defined as the time required for the viscosity of the coating composition to double from its initial value. A short pot life means that, once the two components are combined, the coating composition must be quickly applied to the target substrate else it becomes unworkable due to the increasing viscosity. Alternatively, a short pot life means that the applicator must mix small batches of the coating composition that can be consumed before the reaction progresses to a point that the composition becomes unworkable. Given these competing interests, the catalyst system ideally provides a balance between a suitably long pot life and a short reaction time once the coating is applied.

[0004] Tin-based catalysts have frequently been used in 2K poly coating compositions. These catalysts can be formulated to provide the balance between cure time and pot life that has enabled 2K poly coating compositions to be used in a wide variety ofapplications. However, the use of tin-based catalysts is being met with increased scrutiny from regulatory bodies and industry due to toxicity concerns with known tin-based catalysts. Accordingly, coating formulators are seeking alternative catalyst systems that can provide performance similar to, if not better than, known tin-based catalysts.

[0005] A need therefore remains for catalyst systems that do not contain toxic, tin- based catalysts but provide a balance between cure time and pot life in two-component coating compositions (e.g., 2K poly coating compositions). The catalyst compositions and coating compositions described herein aim to meet this need.BRIEF SUMMARY OF THE INVENTION

[0006] In a first embodiment, the invention provides a catalyst composition comprising (a) a bismuth catalyst comprising a bismuth salt of a first alkyl carboxylic acid; (b) a zinc catalyst comprising a zinc salt of a second alkyl carboxylic acid; and (c) a phosphorus- containing additive. The phosphorus-containing additive can be selected from the group consisting of (i) orthophosphoric acid, (ii) alkyl phosphonic acids, (iii) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; (iv) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; and (v) mixtures thereof.

[0007] The catalyst composition described herein is believed to be well suited for use in catalyzing two-component coating compositions, such as 2K poly coating compositions. When employed in such coating compositions, the catalyst composition exhibits balanced activity that provides a desirable pot life to facilitate application of the coating to the target substrate and produces a coating that cures to hardness in the desired timeframe.

[0008] Thus, in a second embodiment, the invention provides a coating composition comprising the catalyst composition described above. In particular, the coating composition comprises (a) a polyol; (b) an isocyanate compound; and (c) a catalyst composition as described herein.DETAILED DESCRIPTION OF THE INVENTION

[0009] In a first embodiment, the invention provides a catalyst composition comprising (a) a bismuth catalyst, (b) a zinc catalyst, and (c) a phosphorus-containing additive.

[0010] The bismuth catalyst in the catalyst composition can be any suitable bismuth catalyst. In a preferred embodiment, the bismuth catalyst comprises a bismuth salt of a first carboxylic acid. The bismuth salt can contain bismuth in any suitable oxidation state, suchas the +1 [i.e. , Bi(l)], +2 [i.e. , Bi(ll)], +3 [i.e. , Bi(lll)], and +5 [i.e. , Bi(V)] oxidation states. In a preferred embodiment, the bismuth catalyst comprises a bismuth (III) salt.

[0011] As noted above, the bismuth catalyst comprises a bismuth salt of a first carboxylic acid. The first carboxylic acid can be any suitable carboxylic acid. Suitable first carboxylic acids include aliphatic carboxylic acids, such as C4-C28 aliphatic carboxylic acids. In a preferred embodiment, the first carboxylic acid is a C4-C12 alkyl carboxylic acid. Suitable C4-C12 alkyl carboxylic acids include linear C4-C12 alkyl carboxylic acids and branched C4-C12 alkyl carboxylic acids. In a preferred embodiment, the first carboxylic acid is a branched alkyl carboxylic acid, more preferably a branched C4-C12 alkyl carboxylic acid which comprises a branched C3-C11 alkyl group. In one preferred embodiment, the first carboxylic acid is neodecanoic acid. Thus, the bismuth catalyst preferably comprises a bismuth salt of neodecanoic acid. More preferably, the bismuth catalyst comprises bismuth (III) neodecanoate.

[0012] The zinc catalyst in the catalyst composition can be any suitable zinc catalyst. In a preferred embodiment, the zinc catalyst comprises a zinc salt of a second carboxylic acid. The zinc salt can contain zinc in any suitable oxidation state, such as the +1 [i.e., Zn(l)] and +2 [i.e., Zn(ll)] oxidation states. In a preferred embodiment, the zinc catalyst comprises a zinc (II) salt.

[0013] The zinc catalyst comprises a zinc salt of a second carboxylic acid. The second carboxylic acid can be any suitable carboxylic acid and can be the same as or different from the first carboxylic acid in the bismuth catalyst. Suitable second carboxylic acids include aliphatic carboxylic acids, such as C4-C28 aliphatic carboxylic acids. In a preferred embodiment, the second carboxylic acid is a C4-C12 alkyl carboxylic acid. Suitable C4-C12 alkyl carboxylic acids include linear C4-C12 alkyl carboxylic acids and branched C4-C12 alkyl carboxylic acids. In a preferred embodiment, the second carboxylic acid is a branched alkyl carboxylic acid, more preferably a branched C4-C12 alkyl carboxylic acid which comprises a branched C3-C11 alkyl group. In one preferred embodiment, the second carboxylic acid is neodecanoic acid. Thus, the zinc catalyst preferably comprises a zinc salt of neodecanoic acid. More preferably, the zinc catalyst comprises zinc (II) neodecanoate, such as the material commonly referred to as neodecanoic acid, zinc salt basic and having CAS No. 84418-68-8.

[0014] The catalyst composition can contain any suitable amount of the bismuth and zinc catalysts. Preferably, the bismuth catalyst and the zinc catalyst are present in the catalyst composition in amounts that provide a ratio of bismuth to zinc (by mass of each metal) of about 0.9:1 or more. In another embodiment, the ratio of bismuth to zinc preferablyis about 1 :1 or more, more preferably about 1.05:1 or more. While the catalyst composition can comprise more bismuth by mass than zinc, the catalyst composition preferably does not contain too great an excess of bismuth. Accordingly, in another preferred embodiment, the bismuth catalyst and the zinc catalyst are present in the catalyst composition in amounts that provide a ratio of bismuth to zinc (by mass) of about 1.2:1 or less. In other embodiments, the ratio of bismuth to zinc preferably is about 1.15:1 or less. Thus, in a series of preferred embodiments, the bismuth catalyst and the zinc catalyst preferably are present in the catalyst composition in amounts that provide a ratio of bismuth to zinc (by mass) of about 0.9:1 to about 1.2:1 (e.g., about 0.9:1 to about 1.15:1), more preferably about 1 :1 to about 1.2:1 (e.g., about 1 :1 to about 1.15:1) or about 1.05:1 to about 1.15:1.

[0015] As noted above, the catalyst composition further comprises a phosphorus- containing additive. While not wishing to be bound to any particular theory, the phosphorus- containing additive is believed to moderate the activity of the catalyst(s) in the catalyst composition by an unknown mechanism and thereby extend the pot life of a coating composition as compared to a coating composition containing the same catalyst(s) but not the phosphorus-containing additive. The phosphorus-containing additive’s effect on the pot life of the coating composition is believed, in turn, to be affected by the particular catalyst or combination of catalysts present in the coating composition. Indeed, including both a bismuth catalyst and a zinc catalyst in the coating composition has surprisingly been found to moderate the phosphorus-containing additive’s effect on the pot life, enabling one to produce a coating composition whose pot life can be extended and tailored to the particular application at hand.

[0016] The phosphorus-containing additive preferably is selected from the group consisting of (i) orthophosphoric acid, (ii) alkyl phosphonic acids, (iii) phosphoric acid esters, (iv) salts of phosphoric acid esters, and (v) mixtures of any two or more of the foregoing. Suitable alkyl phosphonic acids include, but are not limited to, alkyl phosphonic acids comprising linear or branched C1-C28 alkyl groups, more preferably linear or branched C1-C15 alkyl groups. In a preferred embodiment, the alkyl phosphonic acid comprises a linear C1- C15 alkyl group, such as an n-butyl group or a dodecyl group. Thus, in one preferred embodiment, the phosphorus-containing additive is selected from the group consisting of n- butyl phosphonic acid, dodecyl phosphonic acid, and mixtures thereof.

[0017] Phosphorus-containing additives suitable for use in the additive composition also include phosphoric acid esters and salts of phosphoric acid esters. Suitable phosphoric acid esters are mono-, di-, or tri-esters formally derived from a phosphoric acid (e.g., orthophosphoric acid) and at least one alcohol. As used herein, the term “formally derived”is used in the same sense as in the definition of the term “esters” in IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"), compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). Thus, the phosphoric acid ester need not be made by direct reaction of the phosphoric acid with the alcohol.

[0018] The phosphoric acid ester can be formally derived from any suitable phosphoric acid, but orthophosphoric acid is especially preferred. Alcohols suitable for the phosphoric acid ester include alcohols having linear or branched alkyl groups, such as linear or branched C1-C35 alcohols. Preferably, the alcohol is a linear or branched C6-C35 alcohol, with branched C6-C35 alcohols being particularly preferred (e.g., Ce-Cis alcohols). In one preferred embodiment, the alcohol from which the phosphoric acid ester is formally derived is isotridecyl alcohol. The alcohol can be alkoxylated, for example, by reacting the alcohol with a suitable epoxide (e.g., ethylene oxide, propylene oxide, butylene oxide, or mixtures thereof). Thus, in a preferred embodiment, the phosphorus-containing additive is selected from the group consisting of phosphoric acid esters formally derived from a phosphoric acid (preferably, orthophosphoric acid) and at least one alkoxylated C6-C35 alcohol. In a more preferred embodiment, the phosphorus-containing additive is selected from the group consisting of phosphoric acid esters formally derived from orthophosphoric acid and at least one alkoxylated isotridecyl alcohol, more preferably an ethoxylated isotridecyl alcohol.

[0019] As noted above, suitable phosphorus-containing additives include salts of phosphoric acid esters, such as any of the phosphoric acid esters described above. Such salts can be made by reacting one of the hydroxy groups of a phosphoric acid mono- or diester with a suitable base, such as alkali metal hydroxides, alkaline earth metal hydroxides, hydroxides of ammonium compounds, and amine compounds (e.g., tertiary amines). In a preferred embodiment, the catalyst composition comprises a salt of a phosphoric acid ester, more preferably an amine salt of a phosphoric acid ester. Thus, in one preferred embodiment, the catalyst composition comprises an amine salt (e.g., a quaternary ammonium salt derived from an amine, such as a tertiary amine) of a phosphoric acid ester formally derived from a phosphoric acid (preferably, orthophosphoric acid) and at least one C6-C35 alcohol (preferably, isotridecyl alcohol). In yet another preferred embodiment, the catalyst composition comprises an amine salt (e.g., a quaternary ammonium salt derived from an amine, such as a tertiary amine) of a phosphoric acid ester formally derived from a phosphoric acid (preferably, orthophosphoric acid) and at least one alkoxylated C6-C35 alcohol (preferably, an alkoxylated isotridecyl alcohol). More preferably, the catalyst composition comprises the / V, / V-dimethylcyclohexylammonium salt of a phosphoric acid ester formally derived from a phosphoric acid (preferably, orthophosphoric acid) and at least onealkoxylated C6-C35 alcohol (preferably, an alkoxylated isotridecyl alcohol). In another preferred embodiment, the catalyst composition preferably comprises the N,N- dimethylcyclohexylammonium salt of a phosphoric acid ester formally derived from orthophosphoric acid and at least one ethoxylated isotridecyl alcohol.

[0020] In a preferred embodiment, the phosphorus-containing additive is a phosphoric acid ester compound conforming to the structure of Formula (I) below:In the structure of Formula (I), R1is a group of formula — (R2— O)a— R3, where a is selected from the group consisting of zero and the positive integers from 1 to 100, each R2is an independently selected alkanediyl group, and R3is selected from the group consisting of alkyl groups. X1and X2are independently selected from the group consisting of hydroxy, — (R11— O)b— R12, and —O' (i.e. , a negatively-charged oxygen atom covalently bonded to the phosphorus atom resulting from deprotonation of a hydroxy group on the phosphoric acid), where each b is independently selected from the group consisting of zero and the positive integers from 1 to 100, each R11is an independently selected alkanediyl group, and each R12is an independently selected alkyl group. A is selected from the group consisting of inorganic cations and organic cations. The variable d, which represents the charge on the phosphate ester, is zero if neither of X1and X2is —O', negative one if one of X1or X2is — O', or negative two if both X1and X2are —O'. The variable e is one if d is zero and is a positive integer if d is negative one or negative two. The variable f is a positive integer equal to the valence of the cation A. The variable g is zero if d is zero and is a positive integer if d is negative one or negative two. Further, the values of the variables d, e, f, and g are the values closest to zero that satisfy the equation (de) + (fg) = 0. In a preferred embodiment, each R2and R11is independently selected from the group consisting of C2-C4 alkanediyl groups, such as ethane-1 ,2-diyl, 1-methylethane-1 ,2-diyl, 2-methylethane-1 ,2-diyl, 1- ethylethane-1 ,2-diyl, and 2-ethylethane-1 ,2-diyl. In another preferred embodiment, each R3and R12is independently selected from the group consisting of C1-C35 alkyl groups, more preferably C6-C35 alkyl groups (e.g., Ce-Cis alkyl groups). Preferably, the value of each a and b is independently selected from the group consisting of zero and positive integers from1 to 20 (e.g., 1 to 15 or 1 to 10), with positive integer values for each a and b being more preferred. In a preferred embodiment, A is selected from the group consisting of alkali metal cations, alkaline earth metal cations, group 12 element cations (e.g., a zinc cation), group 13 element cations (e.g., an aluminum cation or a hydroxyaluminum cation), and quaternary ammonium cations (e.g., an / V, / V-dimethylcyclohexylammonium cation).

[0021] Thus, in a series of preferred embodiments, the phosphorus-containing additive comprises a compound of Formula (I) in which:(i) R1is a group of formula — (R2— O)a— R3, where a is selected from the group consisting of zero and the positive integers from 1 to 20, preferably the group consisting of zero and positive integers from 1 to 10, more preferably the group consisting of positive integers from 1 to 20, and even more preferably the group consisting of positive integers from 1 to 10;(ii) each R2is an independently selected C2-C4 alkanediyl group, more preferably an alkanediyl group independently selected from the group consisting of ethane-1 ,2-diyl, 1-methylethane-1 ,2-diyl, 2-methylethane-1 ,2-diyl, 1- ethylethane-1 ,2-diyl, and 2-ethylethane-1 ,2-diyl; and(iii) each R3is independently selected from the group consisting of C1-C35 alkyl groups, more preferably C6-C35 alkyl groups and even more preferably Ce-Cis alkyl groups (e.g., an 11-methyldodec-1-yl group).In a preferred embodiment of each of the foregoing:(iv) X1is —O’;(v) A is a quaternary ammonium cation, more preferably an N,N- dimethylcyclohexylammonium cation;(vi) X2is — (R11— O)b— R12, where b is selected from the group consisting of zero and the positive integers from 1 to 20, preferably the group consisting of zero and positive integers from 1 to 10, more preferably the group consisting of positive integers from 1 to 20, and even more preferably the group consisting of positive integers from 1 to 10;(vii) each R11is an independently selected C2-C4 alkanediyl group, more preferably an alkanediyl group independently selected from the group consisting of ethane-1 ,2-diyl, 1-methylethane-1 ,2-diyl, 2-methylethane-1 ,2- diyl, 1-ethylethane-1 ,2-diyl, and 2-ethylethane-1 ,2-diyl; and(viii) each R12is independently selected from the group consisting of C1-C35 alkyl groups, more preferably C6-C35 alkyl groups and even more preferably Ce-Cis alkyl groups (e.g., an 11-methyldodec-1-yl group).In another preferred embodiment of each of the foregoing:(ix) X1and X2are each —O'; and(x) A is a quaternary ammonium cation, more preferably an N,N- dimethylcyclohexylammonium cation.

[0022] The catalyst composition can contain mixtures of two or more of the phosphorus-containing additives described above. For example, the catalyst composition can contain a mixture of orthophosphoric acid and an alkyl phosphonic acid. Alternatively, the catalyst composition can contain a mixture of at least one phosphoric acid ester and at least one salt of a phosphoric acid ester (e.g., an amine salt of a phosphoric acid ester). Further, when the phosphorus-containing additive comprises a phosphoric acid ester as described above, the phosphorus-containing additive can contain a mixture of monoesters, diesters, and triesters of the phosphoric acid, as well as salts of such monoesters, diesters, and triesters. Preferably, the catalyst composition contains a mixture of a phosphoric acid ester as described above and a salt of such phosphoric acid ester, preferably a quaternary ammonium salt of such phosphoric acid ester.

[0023] The catalyst composition can contain any suitable amount of the phosphorus- containing additive. In order to provide a desirable increase in the pot life of a coating composition, the catalyst composition preferably comprises about 25 wt.% or more of the phosphorus-containing additive, based on the total mass of bismuth, zinc, and phosphorus- containing additive present in the catalyst composition. In other preferred embodiments, the catalyst composition preferably comprises about 30 wt.% or more (more preferably about 35 wt.% or more) of the phosphorus-containing additive, based on the total mass of bismuth, zinc, and phosphorus-containing additive present in the catalyst composition. In order to avoid potentially deleterious effects on the curing (dry time) and / or hardness of a coating made with a coating composition containing the catalyst, the catalyst composition preferably comprises about 80 wt.% or less of the phosphorus-containing additive, based on the total mass of bismuth, zinc, and phosphorus-containing additive present in the catalyst composition. In other preferred embodiments, the catalyst composition preferably comprises about 75 wt.% or less (more preferably about 70 wt.% or less) of the phosphorus-containing additive, based on the total mass of bismuth, zinc, and phosphorus-containing additive present in the catalyst composition. Accordingly, in a series of preferred embodiments, the catalyst composition contains about 25 wt.% to about 80 wt.% (e.g., about 25 wt.% to about 75 wt.% or about 25 wt.% to about 70 wt.%), more preferably about 30 wt.% to about 80 wt.% (e.g., about 30 wt.% to about 75 wt.% or about 30 wt.% to about 70 wt.%), or about 35 wt.% to about 80 wt.% (e.g., about 35 wt.% to about 75 wt.% or about 35 wt.% to about 70wt.%) of phosphorus-containing additive, based on the total mass of bismuth, zinc, and phosphorus-containing additive present in the catalyst composition.

[0024] The catalyst composition can comprise other components in addition to the bismuth catalyst, zinc catalyst, and phosphorus-containing additive described above. For example, the catalyst composition can comprise a suitable solvent or liquid medium in which the components are dispersed. Suitable solvents include, but are not limited to, higher alkanes that are liquid at ambient temperatures, such as C10-C15 alkanes.

[0025] According to particular embodiments, the catalyst composition described herein consists essentially of the bismuth catalyst, zinc catalyst, and phosphorus-containing additive described above. As used herein, the phrases “consists essentially of’ and “consisting essentially of” describe catalyst compositions that contain the enumerated components and, optionally, additional components, provided the inclusion of such additional components does not materially alter or affect the essential characteristics of the catalyst composition. Given that one aim of the catalyst composition is to catalyze the reaction between a polyol and an isocyanate compound while maintaining a desirable pot life for the catalyzed mixture, it will be understood that the inclusion of components that shorten the pot life of the catalyzed mixture below that obtained for the combination of the bismuth catalyst and zinc catalyst alone is excluded from catalyst compositions that consist essentially of the bismuth catalyst, zinc catalyst, and phosphorus-containing additive. Further, given that another aim of the catalyst composition is to reduce the amount of tin-based catalyst(s) used to catalyze the reaction between a polyol and an isocyanate compound, it will be understood that the inclusion of components contributing appreciable amounts of tin (e.g., amounts of tin compounds that would customarily be used to catalyze the reaction) is excluded from catalyst compositions that consist essentially of the bismuth catalyst, zinc catalyst, and phosphorus-containing additive. By way of contrast, it will be understood that the presence of other inert materials (e.g., solvents, surfactants, etc.) that do not materially affect the essential characteristics of the catalyst composition is permitted, and catalyst compositions containing such materials are within the scope of a catalyst composition consisting essentially of the bismuth catalyst, zinc catalyst, and phosphorus-containing additive.

[0026] As noted above, the catalyst composition is believed to be well-suited for use in catalyzing the reaction that occurs in two-component coating compositions, more specifically two-component polyurethane coating compositions. Thus, in a second embodiment, the invention provides a coating composition comprising (a) a polyol, (b) an isocyanate compound, and (c) any of the catalyst compositions described above.

[0027] As utilized herein, the term polyol is used to refer to compounds and polymers comprising two or more hydroxy groups. The coating composition can contain any suitable polyol. Suitable polyols include, but are not limited to, polyester polyols, polyether polyols, polycarbonate polyols, polycarbonate polyester polyols, polyacrylic polyols (i.e. , acrylic polymers comprising two or more hydroxy groups), polyurethane polyols, polycaprolactone polyols, polyolefin polyols, and mixtures of any two or more of the foregoing. In a preferred embodiment, the polyol is an acrylic polymer comprising two or more hydroxy groups (e.g., a hydroxy-functional acrylic polymer).

[0028] The hydroxy-functional acrylic polymers suitable for use in the coating composition can be prepared by free radical polymerization techniques well known in the art. Such acrylic polymers are typically prepared by the addition polymerization of one or more monomers. At least one of the monomers will contain, or can be later reacted to produce, a reactive hydroxy group. Representative hydroxy-functional monomers include 2- hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxybutyl acrylate, 4-hydroxypentyl acrylate, 2-hydroxyethyl ethacrylate, 3-hydroxybutyl methacrylate, 2-hydroxyethyl chloroacrylate, diethylene glycol methacrylate, tetraethylene glycol acrylate, and para-vinyl benzyl alcohol. Typically, the hydroxy-functional monomers would be copolymerized with one or more monomers having ethylenic unsaturation such as:(i) esters of acrylic, methacrylic, crotonic, tiglic, or other unsaturated acids such as: methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, ethylhexyl acrylate, amyl acrylate, 3,5,5- trimethylhexyl acrylate, methyl methacrylate, ethylmethacrylate, propyl methacrylate, dimethylaminoethyl methacrylate, isobornyl methacrylate, ethyl tiglate, methyl crotonate, and ethyl crotonate;(ii) vinyl compounds such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl benzoate, vinyl m-chlorobenzoate, vinyl p- methoxybenzoate, vinyl alpha-chloroacetate, vinyl toluene, and vinyl chloride;(iii) styrene-based materials such as styrene, alpha-methyl styrene, alpha-ethyl styrene, alpha-bromo styrene, and 2,6-dichlorostyrene;(iv) allyl compounds such as allyl chloride, allyl acetate, allyl benzoate, and allyl methacrylate; or(v) other copolymerizable unsaturated monomers such as ethylene acrylonitrile, methacrylonitrile, dimethyl maleate, isopropenyl acetate, isopropenyl isobutyrate, acrylamide, methacrylamide, dienes such as 1,3-butadiene, andhalogenated materials such as 2-( / V-ethylperflourooctenesulfonamido) ethyl(meth)acrylate.

[0029] The hydroxy-functional acrylic polymers are conveniently prepared by conventional free radical addition polymerization techniques. Frequently, the polymerization will be initiated by conventional initiators known in the art to generate a free radical such as azobis(isobutyronitrile), cumene hydroperoxide, or t-butyl perbenzoate. Typically, the monomers are heated in the presence of the initiator at temperatures ranging from about 35 °C to about 200 °C, and especially 75 °C to 150 °C, to affect the polymerization. The molecular weight of the polymer can be controlled, if desired, by the monomer selection, reaction temperature and time, and / or the use of chain transfer agents as is well known in the art.

[0030] The isocyanate compound utilized in the coating composition can be any isocyanate compound, with isocyanate compounds comprising two or more isocyanate groups being particularly preferred. Suitable isocyanate compounds include, but are not limited to aromatic, cycloaliphatic and aliphatic polyisocyanates such as, 1,3- phenylene diisocyanate, 1,4-phenylene diisocyanate, 4-chloro-1,3-phenylene diisocyanate, toluene-2,4- diisocyanate, toluene-2,6-diisocyanate, 1, 2, 4-benzene triisocyanate, 1,5-naphthalene diisocyanate, 1,4-naphthalene diisocyanate, 2,4'- diphenylmethane diisocyanate, 4,4'- diphenylmethane diisocyanate, 3,3'-dimethyl-4,4'-diphenylene diisocyanate, triphenylmethane triisocyanate, polymethylene polyphenyl isocyanate, 1,6-hexamethylene diisocyanate (HDI), isophorone diisocyanate, 4,4-dicyclohexylmethane diisocyanate, 1,6- diisocyanato-2,2,4-trimethylhexane, tri methyl hexamethylene diisocyanate, 1,4-diisocyanato pentane, isocyanatomethylcyclohexyl isocyanate, 1,6,11 -undecane triisocyanate, p- tetramethylxylene diisocyanate, m-tetramethylxylene diisocyanate, 1,4-tetramethylene diisocyanate, 1 ,10-decamethylene diisocyanate, m-xylene diisocyanate, 1 ,3- bis(isocyanatemethyl)cyclohexane, and mixtures thereof.

[0031] The polyol and isocyanate compound can be present in the coating composition in any suitable amount. Typically, the combined mass of the polyol and isocyanate is about 25 wt.% to about 90 wt.% (e.g., about 30 wt.% to about 90 wt.%, about 35 wt.% to about 90 wt.%, about 40 wt.% to about 90 wt.%, or about 40 wt.% to about 85 wt.%) of the total mass of the coating composition. The polyol and isocyanate compound can be present in any suitable relative amounts. Generally, the polyol and isocyanate compound are present in the coating composition in amounts to provide about 0.3 to about 2 equivalents of isocyanate groups for each equivalent of hydroxy groups from the polyol. The polyol and isocyanate compound preferably are present in the coating composition inamounts to provide about 0.7 to about 1.3 equivalents (more preferably, about 0.9 to about 1.3 equivalents, about 1 to about 1.3 equivalents, about 1 to about 1.2 equivalents, or about 1 to about 1.1 equivalents) of isocyanate groups for each equivalent of hydroxy groups from the polyol.

[0032] As noted above, the coating composition comprises any of the catalyst compositions described above. The coating composition can comprise any suitable amount of the catalyst composition. The optimal amount of the catalyst composition will depend upon several factors, such as the amount of polyol and isocyanate in the coating composition, the ratio of the total number of hydroxy groups and total number of isocyanate groups in the coating composition, the concentration of the catalysts and phosphorus- containing additive in the catalyst composition, and the desired pot life of the coating composition once the two components are mixed. Preferably, the coating composition contains about 0.01 wt.% or more (more preferably, about 0.05 wt.% or more) of the catalyst composition based on the total weight of polyol and isocyanate compound in the coating composition. The coating composition preferably contains about 0.5 wt.% or less (more preferably, about 0.2 wt.% or less) of the catalyst composition based on the total weight of polyol and isocyanate compound in the coating composition. Thus, in a series of preferred embodiments, the coating composition preferably contains about 0.01 wt.% to about 0.5 wt.% (e.g., about 0.01 wt.% to about 0.2 wt.) or about 0.05 wt.% to about 0.5 wt.% (e.g., about 0.05 wt.% to about 0.2 wt.%) of the catalyst composition based on the total weight of polyol and isocyanate compound in the coating composition.

[0033] The amount of the catalyst composition added to the coating composition can also be expressed in terms of the resulting amount of one or more of the catalyst composition components in the coating composition. For example, in one preferred embodiment, the catalyst composition is present in the coating composition in an amount to provide about 0.007 wt.% to about 0.01 wt.% (more preferably, about 0.008 wt.% to about 0.009 wt.%) of bismuth based on the total weight of polyol and isocyanate compound in the coating composition. In another preferred embodiment, the catalyst composition is present in the coating composition in an amount to provide about 0.006 wt.% to about 0.01 wt.% (more preferably, about 0.007 wt.% to about 0.009 wt.% or about 0.007 to about 0.008 wt.%) of zinc based on the total weight of polyol and isocyanate compound in the coating composition. In yet another preferred embodiment, the catalyst composition is present in the coating composition in an amount to provide about 0.005 wt.% to about 0.04 wt.% (more preferably, about 0.006 wt.% to about 0.035 wt.%, about 0.007 wt.% to about 0.035 wt.%, or about 0.008 wt.% to about 0.035 wt.%) of the phosphorus-containing additive based on thetotal weight of polyol and isocyanate compound in the coating composition. Thus, in one particularly preferred embodiment, the catalyst composition is present in the coating composition in an amount to provide (i) about 0.007 wt.% to about 0.01 wt.% of bismuth, (ii) about 0.006 wt.% to about 0.01 wt.% of zinc, and (iii) about 0.005 wt.% to about 0.04 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition. In another preferred embodiment, the catalyst composition is present in the coating composition in an amount to provide (i) about 0.008 wt.% to about 0.009 wt.% of bismuth, (ii) about 0.007 wt.% to about 0.009 wt.% of zinc, and (iii) about 0.006 wt.% to about 0.035 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition. In yet another particularly preferred embodiment, the catalyst composition is present in the coating composition in an amount to provide (i) about 0.008 wt.% to about 0.009 wt.% of bismuth, (ii) about 0.007 to about 0.008 wt.% of zinc, and (iii) about 0.007 wt.% to about 0.035 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition. In another preferred embodiment, the catalyst composition is present in the coating composition in an amount to provide (i) about 0.008 wt.% to about 0.009 wt.% of bismuth, (ii) about 0.007 to about 0.008 wt.% of zinc, and (iii) about 0.008 wt.% to about 0.035 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition. When the phosphorus-containing additive is orthophosphoric acid in any of the embodiments described above, the orthophosphoric acid preferably is present in an amount of about 0.007 wt.% to about 0.012 wt.% based on the total weight of polyol and isocyanate compound in the coating composition. When the phosphorus-containing additive is an alkyl phosphonic acid in any of the embodiments described above, the alkyl phosphonic acid preferably is present in an amount of about 0.015 wt.% to about 0.035 wt.% (more preferably, about 0.02 wt.% to about 0.032 wt.%) based on the total weight of polyol and isocyanate compound in the coating composition. When the phosphorus-containing additive is a phosphoric acid ester or a salt of a phosphoric acid ester in any of the embodiments described above, the phosphoric acid ester or salt of the phosphoric acid ester preferably is present in an amount of about 0.009 wt.% to about 0.02 wt.% (more preferably, about 0.01 wt.% to about 0.015 wt.%) based on the total weight of polyol and isocyanate compound in the coating composition.

[0034] The coating composition can contain other ingredients in addition to the polyol, isocyanate compound, and catalyst composition. Examples of such other ingredients include, but are not limited to, solvents, other polymers or polymer dispersions, surfactants, dispersants, defoamers, biocides (e.g. bactericides, fungicides, algaecides and insecticides),fillers, plasticizers, viscosity modifiers (e.g., thickeners), leveling agents, anti-settling agents, crosslinkers, antistatic agents, flame retardants, lubricants, emulsifiers, antifouling agents, pH buffers, corrosion inhibitors, driers, anti-skinning agents, anti-cratering agents, anti-sag agents, heat stabilizers, UV absorbers / inhibitors, antioxidants, wetting agents, antireflective agents, anti-freezing agents, waxes, colorants (including inks and colored pigments), flatteners and other inert pigments (such as titanium dioxide, dyes, clay, amorphous and surface treated silica, calcium carbonate, and the like, and combinations thereof), flow agents, and the like, and various combinations thereof as needed for a particular application. In one particular embodiment, the coating composition can contain one or more pigments. Representative opacifying pigments include white pigments such as titanium dioxide, zinc oxide, antimony oxide, etc. and organic or inorganic chromatic pigments such as iron oxide, carbon black, phthalocyanine blue, etc. The coating composition may also contain extender pigments such as calcium carbonate, clay, silica, talc, etc. The coating composition can also comprise one or more solvents, such as ketone solvents, ester solvents, alcohols, glycol ether solvents, and glycol ether ester solvents. Exemplary, non-limiting examples of solvents that may be useful include xylene, n-butyl acetate, f-butylacetate n-butyl propionate, naphtha, ethyl 3-ethoxypropionate, toluene, methyl ethyl ketone (MEK), acetone, methyl propyl ketone (MPK), methyl-n-amyl ketone (MAK), propylene glycol methylether acetate (PMA) and the like. The coating composition can also contain one or more surface additives (surfactants), such as silicone-based surface additives, which help to reduce surface tension of the coating composition and facilitate wetting of the target substrate.

[0035] The coating composition described above can be produced by combining the polyol (or a composition comprising the polyol), the isocyanate compound (or a composition comprising the isocyanate compound), and a prepared catalyst composition comprising the bismuth catalyst, zinc catalyst, phosphorus-containing additive, and any optional components. Alternatively, the coating composition can be prepared by first combining the polyol (or a composition comprising the polyol) a prepared catalyst composition as described above to produce a polyol composition and then combining the polyol composition and the isocyanate compound (or a composition comprising the isocyanate compound) to produce the coating composition. In yet another alternative, the coating composition can be prepared by first combining the isocyanate compound (or a composition comprising the isocyanate compound) and a prepared catalyst composition as described above to produce an isocyanate composition and then combing the isocyanate composition with the polyol (or a composition comprising the polyol) to produce the coating composition. For each of the alternatives discussed above, the bismuth catalyst, zinc catalyst, and phosphorus-containingadditive can be separately provided (i.e. , the bismuth catalyst, zinc catalyst, and phosphorus-containing additive are individually provided and combined with the polyol and / or isocyanate in place of a previously prepared catalyst composition containing all the components). Alternatively, any two of the bismuth catalyst, zinc catalyst, and phosphorus- containing additive can be provided in a suitable combination (e.g., a composition comprising the bismuth catalyst, zinc catalyst, and optional components) that is then combined with the polyol and / or isocyanate and the remaining third component (e.g., the phosphorus-containing additive or a composition containing the phosphorus-containing additive).

[0036] In some embodiments, the invention provides a kit that comprises two or more formulations comprising the components of the coating composition described above. The formulations of such kits are physically separated from each other, for instance in separate containers, cartridges, sachets, or the like. For example, such a kit can comprise a first formulation comprising the polyol (or a composition comprising the polyol) and the catalyst composition and a second formulation comprising the isocyanate compound (or a composition comprising the isocyanate compound), with each formulation being contained in a cartridge or sachet separating it from the other formulation.

[0037] The coating composition described herein is believed to be suitable for application to any substrate or article by any method. In one embodiment, a method for forming a coated substrate or article is provided whereby any of the coating composition embodiments described above is applied to at least a portion of the surface of the substrate or article. The coating composition is applied to a substrate or article by conventional methods and allowed to cure, typically in ambient air at ambient or slightly elevated temperatures (e.g., up to 80 °C). For example, the coating composition can be applied to the surface of the target substrate or article by spraying, brushing, rolling, padding, or combinations thereof.

[0038] The invention and the potential embodiments thereof described in and embraced by the foregoing description may be further understood by reference to the particular embodiments set forth below. As such, these embodiments are included for illustrative purposes only (e.g., describing potentially preferred embodiments of the invention) and are not intended to limit the foregoing description in any manner.Embodiment 1. A catalyst composition comprising:(a) a bismuth catalyst comprising a bismuth salt of a first alkyl carboxylic acid;(b) a zinc catalyst comprising a zinc salt of a second alkyl carboxylic acid; and(c) a phosphorus-containing additive selected from the group consisting of (i) orthophosphoric acid, (ii) alkyl phosphonic acids, (iii) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; (iv) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; and (v) mixtures thereof, wherein the ratio of the mass of bismuth to zinc is about 0.9: 1 to about 1.2:1.Embodiment 2. A catalyst composition consisting essentially of:(a) a bismuth catalyst comprising a bismuth salt of a first alkyl carboxylic acid;(b) a zinc catalyst comprising a zinc salt of a second alkyl carboxylic acid; and(c) a phosphorus-containing additive selected from the group consisting of (i) orthophosphoric acid, (ii) alkyl phosphonic acids, (iii) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; (iv) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; and (v) mixtures thereof, wherein the ratio of the mass of bismuth to zinc is about 0.9:1 to about 1.2:1.Embodiment 3. The catalyst composition of embodiment 1 or embodiment 2, wherein the first alkyl carboxylic is a C4-C12 alkyl carboxylic acid.Embodiment 4. The catalyst composition of embodiment 3, wherein the first alkyl carboxylic acid comprises a first branched C3-C11 alkyl group.Embodiment 5. The catalyst composition of embodiment 4, wherein the first alkyl carboxylic acid is neodecanoic acid.Embodiment 6. The catalyst composition of any one of embodiments 1-5, wherein the second alkyl carboxylic acid is a C4-C12 alkyl carboxylic acid.Embodiment 7. The catalyst composition of embodiment 6, wherein the second alkyl carboxylic acid comprises a second branched C3-C11 alkyl group.Embodiment 8. The catalyst composition of embodiment 7, wherein the second alkyl carboxylic acid is neodecanoic acid.Embodiment 9. The catalyst composition of any one of embodiments 1-8, wherein the phosphorus-containing additive is selected from the group consisting of C1-C15 alkyl phosphonic acids.Embodiment 10. The catalyst composition of embodiment 9, wherein the alkyl phosphonic acid comprises a linear C1-C15 alkyl group.Embodiment 11 . The catalyst composition of embodiment 9, wherein the phosphorus-containing additive is selected from the group consisting of n-butyl phosphonic acid, dodecyl phosphonic acid, and mixtures thereof.Embodiment 12. The catalyst composition of any one of embodiments 1-11 , wherein the phosphorus-containing additive is selected from the group consisting of (i) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol, (ii) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol, and (iii) mixtures of (i) and (ii).Embodiment 13. The catalyst composition of any one of embodiments 1-8 or 12, wherein the phosphorus-containing additive is selected from the group consisting of (i) phosphoric acid esters formally derived from a phosphoric acid and at least one ethoxylated alcohol, (ii) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one ethoxylated alcohol, and (iii) mixtures of (i) and (ii).Embodiment 14. The catalyst composition of any one of embodiments 1-8 or 12, wherein the catalyst composition comprises a phosphoric acid ester compound of Formula (I)wherein R1is a group of formula — (R2— O)a—3, where a is selected from the group consisting of positive integers from 1 to 20; each R2is an independently selected C2-C4alkanediyl group; R3is selected from the group consisting of C1-C35 alkyl groups; X1and X2are independently selected from the group consisting of hydroxy, — (R11— O)b—12, and — O', where each b is independently selected from the group consisting of positive integers from 1 to 20; each R11is an independently selected C2-C4 alkanediyl group; and each R12is independently selected from the group consisting of C1-C35 alkyl groups; A is selected from the group consisting of inorganic cations and organic cations; the variable d is zero if neither of X1and X2is —O', negative one if one of X1or X2is — O', or negative two if both X1and X2are —O'; the variable e is one if d is zero and is a positive integer if d is negative one or negative two; the variable f is a positive integer equal to the valence of the cation A; the variable g is zero if d is zero and is a positive integer if d is negative one or negative two; and the values of the variables d, e, f, and g are the values closest to zero that satisfy the equation (de) + (fg) = 0.Embodiment 15. The catalyst composition of embodiment 14, wherein each R2and R11is an ethane-1 ,2-diyl group.Embodiment 16. The catalyst composition of embodiment 14 or embodiment 15, wherein each A is a quaternary ammonium cation.Embodiment 17. The catalyst composition of embodiment 16, wherein each A is an / V, / V-dimethylcyclohexylammonium cation.Embodiment 18. The catalyst composition of any one of embodiments 1-8 or 12-17, wherein the phosphorus-containing additive is selected from the group consisting of (i) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated C6-C35 alcohol, (ii) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated C6-C35 alcohol, and (iii) mixtures of (i) and (ii).Embodiment 19. The catalyst composition of any one of embodiments 1-8 or 12-17, wherein the phosphorus-containing additive is selected from the group consisting of (i) phosphoric acid esters formally derived from a phosphoric acid and at least one ethoxylated C6-C35 alcohol, (ii) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one ethoxylated C6-C35 alcohol, and (iii) mixtures of (i) and (ii).Embodiment 20. The catalyst composition of any one of embodiments 1-14, wherein the catalyst composition comprises a phosphoric acid ester compound of Formula (I)wherein R1is a group of formula — (R2— O)a—3, where a is selected from the group consisting of positive integers from 1 to 20; each R2is an independently selected C2-C4 alkanediyl group; R3is selected from the group consisting of C6-C35 alkyl groups; X1and X2are independently selected from the group consisting of hydroxy, — (R11— O)b— R12, and — O', where each b is independently selected from the group consisting of positive integers from 1 to 20; each R11is an independently selected C2-C4 alkanediyl group; and each R12is independently selected from the group consisting of C6-C35 alkyl groups; A is selected from the group consisting of inorganic cations and organic cations; the variable d is zero if neither of X1and X2is —O', negative one if one of X1or X2is — O', or negative two if both X1and X2are —O'; the variable e is one if d is zero and is a positive integer if d is negative one or negative two; the variable f is a positive integer equal to the valence of the cation A; the variable g is zero if d is zero and is a positive integer if d is negative one or negative two; and the values of the variables d, e, f, and g are the values closest to zero that satisfy the equation (de) + (fg) = 0.Embodiment 21 . The catalyst composition of embodiment 20, wherein each R2and R11is an ethane-1 ,2-diyl group.Embodiment 22. The catalyst composition of embodiment 20 or 21 , wherein each A is a quaternary ammonium cation.Embodiment 23. The catalyst composition of embodiment 22, wherein each A is an / V, / V-dimethylcyclohexylammonium cation.Embodiment 24. The catalyst composition of any one of embodiments 1-8 or 12-23, wherein phosphorus-containing additive is selected from the group consisting of (i) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated isotridecyl alcohol, (ii) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated isotridecyl alcohol, and (iii) mixtures of (i) and (ii).Embodiment 25. The catalyst composition of any one of embodiments 1-8 or 12-24, wherein phosphorus-containing additive is selected from the group consisting of (i) phosphoric acid esters formally derived from a phosphoric acid and at least one ethoxylated isotridecyl alcohol, (ii) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one ethoxylated isotridecyl alcohol, and (iii) mixtures of (i) and (ii).Embodiment 26. The catalyst composition of any one of embodiments 1-8 or 12-25, wherein the catalyst composition comprises a phosphoric acid ester compound of Formula (I)wherein R1is a group of formula — (R2— O)a—3, where a is selected from the group consisting of positive integers from 1 to 20; each R2is an independently selected C2-C4 alkanediyl group; R3is an 11-methyldodec-1-yl group; X1and X2are independently selected from the group consisting of hydroxy, — (R11— O)b— R12, and — O', where each b is independently selected from the group consisting of positive integers from 1 to 20; each R11is an independently selected C2-C4 alkanediyl group; and each R12is an 11-methyldodec-1- yl group; A is selected from the group consisting of inorganic cations and organic cations; the variable d is zero if neither of X1and X2is — O', negative one if one of X1or X2is — O', or negative two if both X1and X2are —O'; the variable e is one if d is zero and is a positive integer if d is negative one or negative two; the variable f is a positive integer equal to the valence of the cation A; the variable g is zero if d is zero and is a positive integer if d is negative one or negative two; and the values of the variables d, e, f, and g are the values closest to zero that satisfy the equation (de) + (fg) = 0.Embodiment 27. The catalyst composition of embodiment 26, wherein each R2and R11is an ethane-1,2-diyl group.Embodiment 28. The catalyst composition of embodiment 26 or 27, wherein each A is a quaternary ammonium cation.Embodiment 29. The catalyst composition of embodiment 28, wherein each A is an / V, / V-dimethylcyclohexylammonium cation.Embodiment 30. The catalyst composition of any one of embodiments 1-29, wherein the ratio of the mass of bismuth to zinc is about 1 :1 to about 1.2:1.Embodiment 31. The catalyst composition of embodiment 30, wherein the ratio of the mass of bismuth to zinc is about 1.05:1 to about 1.15:1.Embodiment 32. The catalyst composition of any one of embodiments 1-31, wherein the catalyst composition contains about 25 wt.% to about 80 wt.% of phosphorus- containing additive, based on the total mass of bismuth, zinc, and phosphorus-containing additive present in the catalyst composition.Embodiment 33. A coating composition comprising:(a) a polyol;(b) an isocyanate compound comprising two or more isocyanate groups; and(c) the catalyst composition of any one of embodiments 1-32.Embodiment 34. The coating composition of embodiment 33, wherein the polyol is an acrylic polymer comprising two or more hydroxy groups.Embodiment 35. The coating composition of embodiment 33 or embodiment 34, wherein the coating composition contains about 0.01 wt.% to about 0.2 wt.% of the catalyst composition based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 36. The coating composition of any one of embodiments 33-35, wherein the coating composition contains about 0.05 wt.% to about 0.2 wt.% of the catalyst composition based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 37. The coating composition of any one of embodiments 33-36, wherein the coating composition contains about 0.005 wt.% to about 0.04 wt.% of the phosphorus-containing additive based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 38. The coating composition of any one of embodiments 33-37, wherein the coating composition contains about 0.006 wt.% to about 0.035 wt.% of the phosphorus-containing additive based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 39. The coating composition of any one of embodiments 33-38, wherein the coating composition contains about 0.007 wt.% to about 0.035 wt.% of the phosphorus-containing additive based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 40. The coating composition of any one of embodiments 33-39, wherein the coating composition contains about 0.008 wt.% to about 0.035 wt.% of the phosphorus-containing additive based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 41. The coating composition of any one of embodiments 33-40, wherein the coating composition contains (i) about 0.007 wt.% to about 0.01 wt.% of bismuth, (ii) about 0.006 wt.% to about 0.01 wt.% of zinc, and (iii) about 0.005 wt.% to about 0.04 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 42. The coating composition of any one of embodiments 33-41 , wherein the coating composition contains (i) about 0.008 wt.% to about 0.009 wt.% of bismuth, (ii) about 0.007 wt.% to about 0.009 wt.% of zinc, and (iii) about 0.006 wt.% toabout 0.035 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 43. The coating composition of any one of embodiments 33-42, wherein the coating composition contains (i) about 0.008 wt.% to about 0.009 wt.% of bismuth, (ii) about 0.007 to about 0.008 wt.% of zinc, and (iii) about 0.007 wt.% to about 0.035 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 44. The coating composition of any one of embodiments 33-43, wherein the coating composition contains (i) about 0.008 wt.% to about 0.009 wt.% of bismuth, (ii) about 0.007 to about 0.008 wt.% of zinc, and (iii) about 0.008 wt.% to about 0.035 wt.% of the phosphorus-containing additive, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 45. The coating composition of any one of embodiments 33-43, wherein (i) when the phosphorus-containing additive is orthophosphoric acid, the coating composition contains about 0.007 wt.% to about 0.012 wt.% of orthophosphoric acid, (ii) when the phosphorus-containing additive is an alkyl phosphonic acid, the coating composition contains about 0.015 wt.% to about 0.035 wt.% of the alkyl phosphonic acid, and (iii) when the phosphorus-containing additive is a phosphoric acid ester or a salt of a phosphoric acid ester, the coating composition contains about 0.009 wt.% to about 0.02 wt.% of the phosphoric acid ester or salt of the phosphoric acid ester, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 46. The coating composition of any one of embodiments 33-45, wherein (i) when the phosphorus-containing additive is orthophosphoric acid, the coating composition contains about 0.007 wt.% to about 0.012 wt.% of orthophosphoric acid, (ii) when the phosphorus-containing additive is an alkyl phosphonic acid, the coating composition contains about 0.02 wt.% to about 0.032 wt.% of the alkyl phosphonic acid, and (iii) when the phosphorus-containing additive is a phosphoric acid ester or a salt of a phosphoric acid ester, the coating composition contains about 0.009 wt.% to about 0.02 wt.% of the phosphoric acid ester or salt of the phosphoric acid ester, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 47. The coating composition of any one of embodiments 33-46, wherein (i) when the phosphorus-containing additive is orthophosphoric acid, the coating composition contains about 0.007 wt.% to about 0.012 wt.% of orthophosphoric acid, (ii) when the phosphorus-containing additive is an alkyl phosphonic acid, the coating composition contains about 0.015 wt.% to about 0.035 wt.% of the alkyl phosphonic acid, and (iii) when the phosphorus-containing additive is a phosphoric acid ester or a salt of a phosphoric acid ester, the coating composition contains about 0.01 wt.% to about 0.015 wt.% of the phosphoric acid ester or salt of the phosphoric acid ester, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 48. The coating composition of any one of embodiments 33-47, wherein (i) when the phosphorus-containing additive is orthophosphoric acid, the coating composition contains about 0.007 wt.% to about 0.012 wt.% of orthophosphoric acid, (ii) when the phosphorus-containing additive is an alkyl phosphonic acid, the coating composition contains about 0.02 wt.% to about 0.032 wt.% of the alkyl phosphonic acid, and (iii) when the phosphorus-containing additive is a phosphoric acid ester or a salt of a phosphoric acid ester, the coating composition contains about 0.01 wt.% to about 0.015 wt.% of the phosphoric acid ester or salt of the phosphoric acid ester, all based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 49. The coating composition of any one of embodiments 33-48, wherein the phosphorus-containing additive is orthophosphoric acid, and the coating composition contains about 0.007 wt.% to about 0.012 wt.% of orthophosphoric acid based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 50. The coating composition of any one of embodiments 33-49, wherein the phosphorus-containing additive is an alkyl phosphonic acid, and the coating composition contains about 0.015 wt.% to about 0.035 wt.% of the alkyl phosphonic acid based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 51. The coating composition of any one of embodiments 33-49, wherein the phosphorus-containing additive is an alkyl phosphonic acid, and the coating composition contains about 0.02 wt.% to about 0.032 wt.% of the alkyl phosphonic acid based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 52. The coating composition of any one of embodiments 33-49, wherein the phosphorus-containing additive is a phosphoric acid ester or a salt of a phosphoric acid ester, and the coating composition contains about 0.009 wt.% to about 0.02 wt.% of the phosphoric acid ester or salt of the phosphoric acid ester based on the total weight of polyol and isocyanate compound in the coating composition.Embodiment 53. The coating composition of any one of embodiments 33-49, wherein the phosphorus-containing additive is a phosphoric acid ester or a salt of a phosphoric acid ester, and the coating composition contains about 0.01 wt.% to about 0.015 wt.% of the phosphoric acid ester or salt of the phosphoric acid ester based on the total weight of polyol and isocyanate compound in the coating composition.

[0039] The following examples further illustrate the subject matter described above but, of course, should not be construed as in any way limiting the scope thereof.EXAMPLE 1

[0040] This example demonstrates the improvements in pot-life for a 2K poly coating composition that can be achieved using the catalyst compositions described herein.

[0041] Several two-component polyurethane coating compositions were produced using a first component (Component A) containing a hydroxy-functional acrylic polymer / resin and a second component (Component B) containing an isocyanate compound. The coating composition for each sample was made by first combining the ingredients of Component A (as noted in Table 1) and mixing the ingredients for approximately two minutes using a speed mixer running at approximately 2,000 rpm. After mixing, the resulting Component A was then left to rest under ambient conditions for approximately 24 hours. Finally, the coating composition for the sample was made by combining approximately two parts (by mass) of Component A with one part (by mass) of an isocyanate compound (Component B). Specifically, Component B for all coating compositions was an aliphatic polyisocyanate (Desmodur® N 75 BA from Covestro AG).Table 1. Component A for coating composition formulations used to produce Samples 1-1 to 1-18.

[0042] In Table 2 below, the bismuth additive used in each coating composition contained a bismuth salt of neodecanoic acid and had a bismuth content (by mass) of approximately 16%. The zinc additive used in each coating composition contained a zinc salt of neodecanoic acid and had a zinc content (by mass) of approximately 15%. The phosphorus-containing additive (“P-containing Additive”) used in the coating composition for each sample is noted in Table 2. “DDPA” denotes dodecyl phosphonic acid, and “NBPA” denotes n-butyl phosphonic acid. “PAE1” denotes a phosphorus-containing additive containing an amine salt of the phosphoric acid ester formally derived from orthophosphoric and an ethoxylated isotridecyl alcohol, specifically CAS No. 164383-18-0.

[0043] The amount of bismuth catalyst and / or zinc catalyst in each coating composition is reported in Table 2 as the percentage of metal based on the resin solids in the coating composition (% MORS). The % MORS was calculated using the following formula: mcx MCc% MORS =~scf100%X mfIn the formula, mcis the mass of the catalyst in grams, MCcis the metal content of the catalyst expressed as a percentage of the total mass of the catalyst, SCf is the resin solids content of the coating composition expressed as a percentage of the total mass of the coating composition, and if is the mass of the coating composition in grams.

[0044] The amount of phosphorus-containing additive in each coating composition is reported in Table 2 as the percentage of additive based on the resin solids in the coating composition (% WORS). The % WORS was calculated using the following formula:171% WORS =sca-Too%x mfIn the formula, mais the mass of the phosphorus-containing additive in grams, SCf is the resin solids content of the coating composition expressed as a percentage of the total mass of the coating composition, and if is the mass of the coating composition in grams.

[0045] The pot life of each coating composition was measured as described herein. All viscosities were measured at 23 °C and a shear rate of 1000 s-1using an Anton Paar MCR-302 rheometer fitted with a geometry cone plate 25-1. The initial viscosity of each coating composition was measured immediately after Component A and Component B were combined as described above. The viscosity of each coating composition was then measured again at 15- to 30-minute intervals until the viscosity doubled from its initial value. The pot life is reported in Table 2 as the time (in minutes) it took for the viscosity of the coating composition to double from its initial value.Table 2.

[0046] As can be seen from the data in Table 2, the coating composition containing only the bismuth catalyst (i.e., Sample 1-1) had a pot life of only 30 minutes, which is generally considered too short for practical applications. The addition of 0.0087% WORS of orthophosphoric acid (Sample 1-5) extended the pot life to greater than 360 minutes. The coating composition containing only the zinc catalyst (Sample 1-2) had a pot life of 310 minutes, and the addition of 0.0087% WORS of orthophosphoric acid (Sample 1-6) again extended the pot life to greater than 360 minutes. The coating composition containing the combination of the bismuth catalyst and the zinc catalyst (Sample 1-3) exhibited a pot life of 60 minutes. Surprisingly, using a combination of a bismuth catalyst and a zinc catalyst in the coating composition was observed to moderate the phosphorus-containing additive’s effect on extending the pot life. This can be seen in the data for Samples 1-7 to 1-12, where the addition of orthophosphoric acid generally produced a less pronounced increase in the pot life as compared to those increases observed in coating compositions catalyzed with only one catalyst. For example, the addition of 0.0087% WORS of orthophosphoric acid (Sample 1-9) resulted in a pot life of 90 minutes, which was only 30 minutes greater than the coating composition containing the two catalysts without any phosphorus-containing additive (Sample 1-3). The addition of the same amount of orthophosphoric acid to a coating composition containing either the bismuth catalyst or zinc catalyst alone resulted in a pot life that exceeded 360 minutes (see, Samples 1-5 and 1-6 as discussed above). Indeed, when both the bismuth catalyst and the zinc catalyst were used, the pot life of the coating composition did not exceed 360 minutes until the concentration of the orthophosphoric acid reached 0.0175% WORS (Sample 1-12).

[0047] Without wishing to be bound to any particular theory, the inventors believe a pot life of 60 minutes or more is preferable for the type of coating composition used in this example, with more desirable ranges being from 90 to 200 minutes or from 90 to 120 minutes. The data in Table 2 show a pot life within this range was achieved when both a bismuth catalyst and zinc catalyst were used in combination with a variety of phosphorus- containing additives as described herein (see, e.g., Samples 1-9, 1-10, 1-13, 1-14, and 1- 15).

[0048] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0049] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the subject matter of this application (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e. , meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the subject matter of the application and does not pose a limitation on the scope of the subject matter unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the subject matter described herein.

[0050] Preferred embodiments of the subject matter of this application are described herein, including the best mode known to the inventors for carrying out the claimed subject matter. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the subject matter described herein to be practiced otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matterrecited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

CLAIMS1. A catalyst composition comprising:(a) a bismuth catalyst comprising a bismuth salt of a first alkyl carboxylic acid;(b) a zinc catalyst comprising a zinc salt of a second alkyl carboxylic acid; and(c) a phosphorus-containing additive selected from the group consisting of (i) orthophosphoric acid, (ii) alkyl phosphonic acids, (iii) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; (iv) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated alcohol; and (v) mixtures thereof, wherein the ratio of the mass of bismuth to zinc is about 0.9:1 to about 1.2:1.

2. The catalyst composition of claim 1 , wherein the first alkyl carboxylic is a C4- C12 alkyl carboxylic acid.

3. The catalyst composition of claim 2, wherein the first alkyl carboxylic acid is neodecanoic acid.

4. The catalyst composition of any one of claims 1-3, wherein the second alkyl carboxylic acid is a C4-C12 alkyl carboxylic acid.

5. The catalyst composition of claim 4, wherein the second alkyl carboxylic acid is neodecanoic acid.

6. The catalyst composition of any one of claims 1-5, wherein the phosphorus- containing additive comprises one or more C1-C15 alkyl phosphonic acids.

7. The catalyst composition of claim 6, wherein the alkyl phosphonic acids comprise a linear C1-C15 alkyl group.

8. The catalyst composition of claim 6, wherein the phosphorus-containing additive comprises one or more compounds selected from the group consisting of n-butyl phosphonic acid, dodecyl phosphonic acid, and mixtures thereof.

9. The catalyst composition of any one of claims 1-8, wherein the phosphorus- containing additive comprises one or more compounds selected from the group consisting of (i) phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated C6-C35 alcohol, (ii) salts of phosphoric acid esters formally derived from a phosphoric acid and at least one alkoxylated C6-C35 alcohol, and (iii) mixtures of (i) and (ii).

10. The catalyst composition of any one of claims 1-9, wherein the ratio of the mass of bismuth to zinc is about 1 :1 to about 1.2:1, preferably about 1.05:1 to about 1.15:1.

11. The catalyst composition of any one of claims 1-10, wherein the catalyst composition contains about 25 wt.% to about 80 wt.% of phosphorus-containing additive, based on the total mass of bismuth, zinc, and phosphorus-containing additive present in the catalyst composition.

12. A coating composition comprising:(a) a polyol;(b) an isocyanate compound comprising two or more isocyanate groups; and(c) the catalyst composition of any one of claims 1-11.

13. The coating composition of claim 12, wherein the polyol is an acrylic polymer comprising two or more hydroxy groups.

14. The coating composition of claim 12 or claim 13, wherein the coating composition contains about 0.01 wt.% to about 0.2 wt.% of the catalyst composition based on the total weight of polyol and isocyanate compound in the coating composition.

15. The coating composition of any one of claims 12-14, wherein the coating composition contains about 0.05 wt.% to about 0.2 wt.% of the catalyst composition based on the total weight of polyol and isocyanate compound in the coating composition.

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