HK1138031B - Silicone resin containing coating compositions, related coated substrates and methods - Google Patents

Description

Coating compositions containing silicone resins, related coated substrates and methods

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part application of U.S. patent application No. 10/943241 entitled "fast curing modified silicone composition" filed on 9, 15 of 2004.

Technical Field

The present invention relates to silicone-containing coating compositions. More particularly, the present invention relates to silicone containing (a) alkoxy-functional and/or silanol-functional groups; and (b) an epoxy-functional silicone.

Background

The use of silicone resins in forming protective coatings may, in some applications, contribute to the properties of flexibility, impact resistance, and/or weatherability of the resulting cured coatings. In some cases, the combination of polysiloxane resins with epoxy resins provides improved impact resistance, flexibility, corrosion resistance, and/or weatherability of the resulting coatings.

Silicone resins are sometimes used with base resin materials, such as epoxy resins, and are reacted by acid or base catalyzed hydrolysis of the silicone resin and aminosilane, followed by condensation of the resulting silanol groups formed during the hydrolysis of the amine and reaction with the epoxy groups. This reaction mechanism can be initiated by the presence of moisture, which is carried out in the presence of an amine (product), and is accomplished by evaporation of the alcohol-driven reaction formed during the hydrolysis reaction. While such epoxy-polysiloxane coating compositions can be used to form protective coatings that provide a certain coating hardness, flexibility, impact resistance, weatherability, and corrosion and/or chemical resistance to the underlying substrate, the need to provide coatings with reduced volatile organic solvent content (VOC) sometimes requires the use of lower molecular weight resins in such coating formulations.

However, the disadvantage of using such lower molecular weight resins is that the desired coating properties described above are increased by increasing the crosslink density of these resins, which may result in coatings with a reduced degree of flexibility. In some cases, organic materials, such as acrylics and/or acrylate functional ingredients, such as acrylate oligomers, are included in these compositions to provide improved flexibility. These materials can also sometimes be used to reduce the drying or curing time of the coating over a wide temperature range. However, these materials have the disadvantage that they can have reduced weathering resistance and/or stability.

It would therefore be desirable to provide coating compositions comprising silicone resins that, at least in some cases, provide coatings with flexibility, hardness, impact resistance, corrosion resistance, and/or chemical resistance to the same or better extent than known polysiloxane coating compositions comprising acrylic resin and/or acrylate functional ingredients, while at the same time providing these properties within the compositions, wherein, at least in some cases, these compositions may have improved weatherability and/or stability. Moreover, it may be desirable to provide such coating compositions that, at least in some cases, are "fast curing".

Summary of The Invention

In some aspects, the present invention relates to a coating composition comprising (a) an alkoxy-functional and/or silanol-functional silicone; (b) an epoxy-functional silicone; and (c) a curing agent.

In other aspects, the present invention relates to a coating composition comprising (a) an alkoxy-functional and/or silanol-functional silicone; (b) an epoxy-functional silicone; and (c) a hydroxy-functional and/or epoxy-functional component different from (a) and (b); and (d) a curing agent.

The invention also relates, inter alia, to substrates at least partially coated with a coating deposited from such a composition, methods of making the composition, and methods of at least partially coating a substrate with the composition.

Detailed Description

For purposes of the following detailed description, it is to be understood that the invention may assume various alternative variations and step sequences, with exceptions expressly stated to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients 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 invention. 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.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

Moreover, it should be understood that all numerical ranges recited herein are intended to include all sub-ranges recited therein. For example, a range of "1 to 10" is intended to include all sub-ranges 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 of equal to or less than 10.

In this application, the use of the singular includes the plural, and the plural includes the singular, unless specifically stated otherwise. In addition, in this application, the use of "or" means "and/or," unless specifically stated otherwise, even though in some cases "and/or" may be explicitly used.

As noted, some embodiments of the present invention are directed to coating compositions. In some embodiments, the coating compositions of the present invention are embodied in a two-component system in which the ingredients are provided in two separate containers, which are combined and mixed together prior to use. For example, in some embodiments, the coating compositions of the present invention are embodied in a two-component system, wherein the first component comprises (i) an alkoxy-functional and/or silanol-functional silicone, and (ii) an epoxy-functional silicone; and the second component includes a curing agent. In other embodiments, the coating compositions of the present invention are provided in the form of a single component system, wherein all of the coating components are combined in a single container.

In some embodiments, the coating compositions of the present invention comprise a modified silicone composition. As used herein, the term "modified silicone composition" means that the composition includes a silicone in combination with other resin ingredients, such as acrylics, polyesters, polyethers, and/or polyurethanes, to provide a copolymer or Interpenetrating Polymer Network (IPN) having hybrid properties of impact resistance, flexibility, weatherability, corrosion resistance, and/or chemical resistance not provided by the silicone resin-containing composition alone. These properties may be a result of selection of the ingredients, the relative amounts of the ingredients, and/or the manner in which the ingredients are selected to be combined together.

As previously mentioned, in some embodiments, the coating compositions of the present invention comprise alkoxy-functional and/or silanol-functional silicones. In other words, the coating composition of the present invention comprises an alkoxy-functional silicone, a silanol-functional silicone, or a mixture thereof. The term "alkoxy-functional and/OR silanol-functional silicone" as used herein refers to a silicone containing alkoxy-functional groups-OR and/OR hydroxyl-functional groups-OH, wherein R is an alkyl OR aryl group. The term "silicone" as used herein refers to a polysiloxane polymer that is based on a structure containing alternating silicon and oxygen atoms. In some embodiments, the alkoxy-functional and/or silanol-functional silicone comprises a compound represented by the general formula:wherein each R is₁Which may be the same or different, are selected from hydroxyl, alkyl having up to 6 carbon atoms, aryl having up to 6 carbon atoms, and alkoxy having up to 6 carbon atoms; each R₂Which may be the same or different, are selected from hydrogen, alkyl groups having up to 6 carbon atoms, and aryl groups having up to 6 carbon atoms. In some embodiments, R₁And R₂Groups having less than 6 carbon atoms are included to promote rapid hydrolysis, the reaction being driven by the volatility of the alcohol-like product during hydrolysis. In some embodiments, "n" is selected so that the aforementioned silicone has a weight average molecular weight in the range of 400-.

Alkoxy-functional and/or silanol-functional silicones suitable for use in the present invention are commercially available and include, for example, (a) methoxy-functional silicones such as DC-3074 and DC-3037 commercially available from Dow Corning; and GE SR191, SY-550 and SY-231 commercially available from Wacker Silicones located in Adrian, Michigan; and (b) silanol-functional silicones such as Dow Corning's DC-840, Z6018, Q1-2530, and 6-2230.

In some embodiments, the alkoxy-functional and/or silanol-functional silicone described previously is present in the coating composition of the present invention in an amount ranging from 5 to 80 percent by weight, such as from 10 to 30 percent by weight, or in some cases, from 10 to 25 percent by weight, with the weight percents being based on the total weight of the coating composition.

As previously mentioned, the coating composition of the present invention also includes an epoxy-functional silicone. As used herein, the term "epoxy-functional silicone" refers to a silicone containing epoxy functional groupsThe silicone of (4). In some embodiments, the coating compositions of the present invention comprise an epoxy-functional silicone comprising a plurality of epoxy-functional groups, i.e., two or more epoxy-functional groups. In some embodiments of the invention, the coating composition comprises an epoxy-functional silicone comprising two epoxy-functional groups.

In some embodiments, the coating compositions of the present invention comprise an epoxy-functional silicone represented by one of the following general structures:orWherein m is an integer having a value in the range of 1 to 10,000, such as 5 to 10,000; n is an integer having a value in the range of 1 to 100, such as 2 to 100; and each X, which may be the same or different, represents an epoxy-containing group, i.e., a moiety containing an epoxy functional group, such as:orSpecific examples of such epoxy-functional silicones suitable for use in the present invention include those represented by the following general structure:and those represented by the following general structure:epoxy-functional silicones of the type discussed in this paragraph are commercially available. Examples include CoatOSiol commercially available from GEadvanced Materials, Wilton, CT^TM2810; KF-101, KF-102, KF-105 and KF-1000 commercially available from Shin-Etsu Chemical Co., Ltd.; and commercially available from Tego ChemieAndEW。

epoxy-functional silicones suitable for use in the present invention and methods for their preparation are also disclosed at column 3, line 66 to column 6, line 62 of U.S. patent No.6713586, the citations of which are incorporated herein by reference. In some embodiments of the invention, the coating composition comprises an epoxy-functional silicone represented by the general formula:wherein each R is³Alkylene of 1 to 18 carbon atoms, which may be the same or different, optionally interrupted by oxygen (provided that oxygen is not bonded to the Si-group), or arylene; each R⁴Which may be the same or different, is an alkyl group, an aryl group, a vinyl group, a glycol, an alkoxy group having 1 to 8 carbon atoms, or an epoxy group (provided that oxygen is not bonded to the Si-group); and n is greater than or equal to 1. Epoxy-functional Silicones of the type discussed in this paragraph are commercially available and include those commercially available from Wacker SiliconesHP-1000 and HP-1250.

In some embodiments, the epoxy-functional silicone described previously is present in the coating composition of the present invention in an amount ranging from 5 to 80 percent by weight, such as from 10 to 30 percent by weight, or in some cases, from 5 to 20 percent by weight, where the weight percents are based on the total weight of the coating composition. In some embodiments, the weight ratio of alkoxy-functional and/or silanol-functional silicone to epoxy-functional silicone is at least 1: 1, in some cases at least 2: 1, and in yet other cases from 2: 1 to 3: 1.

In addition to the aforementioned components, the coating composition of the present invention also includes a curing agent. Suitable curing agents include, for example, amines, aminosilanes, ketimines, aldimines, and mixtures thereof. In some embodiments of the coating composition of the present invention, the curing agent reacts with the epoxy functional groups of the epoxy functional silicone described previously. In some embodiments, the curing agent may also react with other components in the coating composition, such as some components described in detail below.

Suitable amine curing agents for use in the present invention include polyamines, aliphatic amine adducts, polyamidoamines, cycloaliphatic amines and polyamines, and cycloaliphatic amine adducts, and aromatic amines, as described in U.S. patent application publication 2006/0058451 [0051], the citation of which is incorporated herein by reference.

Suitable aminosilane curing agents for use in the present invention include those having the general formula Y-Si- (O-X)_nWherein n is 2 or 3; each X, which may be the same or different, is an alkyl, hydroxyalkyl, alkoxyalkyl or hydroxyalkoxyalkyl group having less than 6 carbon atoms; and Y is H (HNR)_cWherein c is an integer having a value of 1 to 6; and each R is a difunctional organic radical independently selected from the group consisting of aryl, alkyl, dialkylaryl, alkoxyalkyl, and cycloalkyl radicals, wherein R may vary within each Y molecule. These materials are further disclosed in U.S. patent application publication No.2006/0058451 [0052 ]]-[0054]The citation of which is hereby incorporated by reference.

Suitable ketimine and aldimine curing agents for use in the present invention include those obtained by reacting amines with either ketones or aldehydes, respectively, and include those materials described in U.S. patent application publication No.2006/0058451 [0055], the citation portions of which are incorporated herein by reference.

In the coating of the inventionIn some embodiments of the composition, the curative comprises a compound of the formula BR_eSi(OR³)_3-eIn which R is C_1-18A hydrocarbyl group; r³Is an alkyl group having 1 to 8 carbon atoms; e is 0, 1 or 2; and B is of the formula-CR² ₂A radical of-Y, wherein R²Is hydrogen or an alkyl group having 1 to 4 carbon atoms, and Y is a nitrogen atom-containing group. Indeed, it is believed that the use of this curing agent in the coating composition of the present invention may result in, at least in some cases, a coating with further improved flexibility. Moreover, the coating compositions of the present invention formulated using this curing agent are believed to be "fast-curing" compositions in at least some instances, even in the absence of amine-reactive components selected from the group consisting of the acetoacetate-functional components, acrylate-functional components described below. The term "fast-curing" composition as used herein refers to a composition that can form a dust-free film in as little as 1 hour, in some cases 45 minutes, in some cases as little as 10 minutes, or in other cases as little as 5 minutes when applied to a substrate at 25 ℃ and 70% relative humidity.

An example of a suitable Y radical in the preceding paragraph is-NH₂、-NHR⁴and-NR⁴ ₂Wherein R is⁴Is a monovalent organic group optionally containing nitrogen and/or oxygen atoms, such as a monovalent hydrocarbon group optionally containing nitrogen and/or oxygen atoms and having 1 to 18 carbon atoms. Examples of suitable B radicals in the preceding paragraph are aminomethyl, methylaminomethyl, dimethylaminomethyl, diethylaminomethyl, dibutylaminomethyl, cyclohexylaminomethyl, anilinomethyl, 3-dimethylaminopropylaminomethyl, bis (3-dimethylaminopropyl) aminomethyl and the formula-CH₂NHCOR⁴、-CH₂NHCO₂R⁴or-CH₂NHCONHR⁴Wherein R is⁴As defined above.

Suitable for use in the present invention are of the formula BR_eSi(OR³)_3-eSpecific examples of the aminosilane include diethylaminomethylmethyldimethoxysilane, dibutylaminomethyltris (methyl-bis (hydroxymethyl)) silaneEthoxysilane, dibutylaminomethyltributoxysilane, cyclohexylaminomethyltrimethoxysilane, cyclohexylaminomethyltriethoxysilane, cyclohexylaminomethylmethyldiethoxysilane, anilinomethyltriethoxysilane, 3-dimethylaminopropylaminomethyltrimethoxysilane and acetylaminomethylmethyldimethoxysilane. These materials are disclosed in U.S. patent No.7126020 at column 2, lines 37-49 and column 3, line 62 to column 4, line 52, the citations of which are incorporated herein by reference. In addition, these materials may also be trademarkedFor exampleXL 924, XL 926 and XL 973 are commercially available from Wacker Silicones.

As will be appreciated, the type of curing agent selected for inclusion in the coating composition of the present invention will often depend on the particular type of application and the type of other ingredients used. As is also understood, combinations of more than one type of curing agent may be used to form the coating compositions of the present invention. For example, and without limitation, primary and/or secondary amines may be used in combination with aminosilanes. Additionally, polyether amino functional amines can be used to make the curative package flexible and/or also to reduce the raw material cost of the curative material. Secondary amines can be used to add epoxy functionality and form highly reactive polymers, such as star polymers.

In some embodiments, the curing agent is present in the coating composition in an amount ranging from 1 to 30 weight percent, such as from 2 to 25 weight percent, or, in some cases, from 5 to 18 weight percent, where the weight percent is based on the total weight of the coating composition. It will be appreciated that one or more of the above-described curing agents may be used, and the total amount of such curing agents used is within the above-described ranges, depending on the particular desired method of preparing the composition, and the desired properties of the resulting cured film coating.

In addition to the components previously described, the coating compositions of the present invention may also include any of a variety of additional optional components, for example, in some embodiments, the coating compositions of the present invention include hydroxyl-functional and/or epoxy-functional ingredients other than the silicones previously described. However, in other embodiments, the coating compositions of the present invention are substantially free of this component, or in some cases, completely free of this component. As used herein, when a coating composition of the present invention is considered to be "substantially free" of a particular material, it means that the material in question, if any, is present in the composition as an incidental impurity. In other words, the material does not affect the properties of the composition. Further, when a coating composition of the present invention is considered "completely free" of a particular material, it means that the material is not present in the composition at all.

Examples of suitable hydroxy-functional components other than the silicones described above are carbinols (carbinols) selected from acrylic resins, polyester resins, phenolic silane resins and mixtures thereof. Such resins are disclosed in U.S. patent No.6013752 at column 6, line 57 to column 8, line 19, the citations of which are incorporated herein by reference.

Examples of suitable epoxy-functional ingredients other than the silicones described previously include those selected from epoxy resins, i.e., resins containing more than one 1, 2-epoxy group per molecule, and epoxy-functional acrylic resins, epoxy-functional silanes, and combinations thereof.

Suitable epoxy resins having more than one 1, 2-epoxy group per mole include, for example, those that are saturated or unsaturated, aliphatic, cycloaliphatic or heterocyclic. In some embodiments, such epoxy resins are liquids rather than solids, have an epoxy equivalent weight of 100-. Suitable such polyepoxides are disclosed in U.S. patent No.3183198 at column 3, line 27 to column 4, line 64, the citations of which are incorporated herein by reference. In some embodiments, the epoxy resin used may also contain some monomeric units having only one oxirane group. Suitable epoxy resins are commercially available and include those described in U.S. patent application publication No.2006/0058451 [0043], the cited portion of which is incorporated herein by reference, and those described in U.S. patent No.6639025 at column 3, line 11 through column 4, line 32, the cited portion of which is incorporated herein by reference.

Suitable epoxy-functional acrylic resins include glycidyl ether functional polymers, Glycidyl Methacrylate (GMA) functional resins, and any epoxy-functional material, such as epoxidized soybean oil or the like. Such resins are commercially available and include those described in U.S. patent application publication No2006/0058451 [0044], the citation of which is incorporated herein by reference.

Suitable epoxy-functional silanes are commercially available and include those described in U.S. patent application publication No2006/0058451 [0045], the citation of which is incorporated herein by reference.

In some embodiments, hydroxy-functional and/or epoxy-functional ingredients other than the silicones described previously are present in the compositions of the invention in an amount ranging from 1 to 50 percent by weight, such as from 2 to 40 percent by weight, or in some cases, from 5 to 35 percent by weight, based on the total weight of the coating composition.

In some embodiments, the coating composition of the present invention comprises 0.65 to 1.35 equivalents of amine groups relative to 1.0 equivalent of epoxy groups.

Additionally, some embodiments of the coating compositions of the present invention include silanes, including those having the general formula:wherein R is₁₆And each R₁₇And R₁₈Independently selected from hydrogen and alkyl, aryl, cycloalkyl, alkoxy, aryloxy, hydroxyalkyl, alkoxyalkyl and hydroxyalkoxyalkyl groups having up to 6 carbon atoms, and wherein R₁₉Selected from hydrogen and alkyl and aryl groups having up to 6 carbon atoms. In some embodiments, at least one group includes an oxygen component for polymerization, and"n" is in the range of 1-5 and may have an average molecular weight in the range of 150-600.

Silanes are optional ingredients in the coating compositions of the present invention, and thus in some embodiments, the coating compositions of the present invention are substantially free of such ingredients, or in some cases, completely free of such ingredients.

Suitable silanes are commercially available and include phenyl/methylmethoxy-silane, which is available, for example, from Dow Corning under the product name QP 8-5314.

In some embodiments, if used, the silane is present in the coating composition of the present invention in an amount of up to 10 weight percent, such as from 0.5 to 5 weight percent, or, in some cases, from 0.85 to 2 weight percent, where the weight percent is based on the total weight of the coating composition.

In some embodiments, particularly in some cases where a "fast cure" composition is desired, the coating composition of the present invention may also include an amine-reactive component selected from the group consisting of acetoacetate-functional components, acrylate-functional components, and mixtures thereof. Because such an amine-reactive ingredient is optional in the coating composition, some embodiments of the coating composition of the present invention are substantially free of such an amine-reactive ingredient, or in some cases, completely free of such an amine-reactive ingredient.

The term "acetoacetate-functional component" as used herein refers to both substituted and unsubstituted acetoacetate-functional components and includes, for example, those selected from the group consisting of acetoacetate-functional diluents, acetoacetate-functional oligomers, acetoacetate-functional polymers, and mixtures thereof.

Suitable acetoacetate-functional ingredients include, for example, those having the formula R₂₀[OCOCH₂COCH₂]_aR₂₁Wherein R is₂₀Can be selected from acrylic, polyester, polyether and polyurethane polymers or diluents, or can be used [ OCOCH₂COCH₂]Any hydroxy-functional polymer that is functionalized,wherein "a" may be 1 to 10, and wherein R₂₁May be hydrogen or may be a carbon-containing group having up to about 6 carbon atoms.

Suitable acetoacetate-functional ingredients are listed in U.S. patent application publication Nos. 2006/0058451 [0022] - [0028], the citation portions of which are incorporated herein by reference.

The term "acrylate functional component" as used herein refers to both substituted and unsubstituted acrylate functional components. Suitable acrylate-functional ingredients include those selected from acrylate-functional diluents, acrylate-functional oligomers, acrylate-functional polymers, and mixtures thereof, and include, for example, those having the following chemical formula R₂₂[OCOCHCH]_bR₂₃Wherein R is₂₂Can be selected from acrylic, polyester, polyether and polyurethane polymers or diluents, or can be used [ OCOCHCH]Any hydroxy-functional polymer that is functionalized, wherein "b" can be 1 to 10, and wherein R₂₃May be hydrogen or may be a carbon-containing group having up to about 6 carbon atoms.

Suitable acrylate-functional ingredients are listed in U.S. patent application publication No.2006/0058451 [0034] - [0038], the citation of which is incorporated herein by reference.

In some embodiments, if used, the aforementioned amine reactive component is present in the coating composition of the present invention in an amount of up to 40 weight percent, such as from 5 to 30 weight percent, or, in some cases, from 7 to 25 weight percent, where the weight percent is based on the total weight of the coating composition.

In some embodiments, the coating compositions of the present invention include an elastomeric resin of the type described in U.S. Pat. No.6639025, column 7, line 38 to column 8, line 37, the citation of which is incorporated herein by reference. In contrast, in other embodiments, the coating compositions of the present invention are substantially free of such an elastomeric resin, or in some cases, completely free of such an elastomeric resin.

In some embodiments, the coating compositions of the present invention include silicon-containing polyethers of the type described in U.S. Pat. No.5703178, column 4, line 64 to column 5, line 43, the citation of which is incorporated herein by reference. In contrast, in other embodiments, the coating compositions of the present invention are substantially free of such silicon-containing polyether, or in some cases, completely free of such silicon-containing polyether.

In some embodiments, the coating compositions of the present invention include silicone fluids of the type described in U.S. patent No.6169066, column 3, line 9 through line 49, the citation of which is incorporated herein by reference. In contrast, in other embodiments, the coating compositions of the present invention are substantially free of such a silicone fluid, or in some cases, completely free of such a silicone fluid.

In some embodiments, the coating compositions of the present invention include an organic halogen-containing ingredient of the type described in U.S. Pat. No.6013752, column 9, line 8 through column 10, line 13, the citation of which is incorporated herein by reference. In contrast, in other embodiments, the coating compositions of the present invention are substantially free of such organic halogen-containing ingredient, or in some cases, completely free of such organic halogen-containing ingredient.

In some embodiments, the coating compositions of the present invention include a catalyst, such as an organometallic catalyst. Suitable organometallic catalysts are useful for the purpose of accelerating the cure rate of the composition into a protective film coating over a wide temperature range. In some applications where ambient temperature cure of the composition is sought, organometallic catalysts may also be used to provide accelerated cure rates under such ambient temperature cure conditions. Suitable catalysts include tin catalysts having the general formula:wherein R is₅And R₆Each independently selected from alkyl, aryl and alkoxy groups having up to 11 carbon atoms, and wherein R is₇And R₈Each independently selected from the group consisting of₅And R₆The same group, or from inorganic atoms, such as halogen, sulfur or oxygen. Exemplary catalysts include organotin materials such as dibutyltin dilaurate, dibutyltin diacetate, dibutyltin diacetyl diacetonate, and organotitanates.

Other useful organometallic catalysts include lead octoate, lead neodecanoate, bismuth nitrate, bismuth octoate, bismuth neodecanoate, bismuth naphthenate, versalate bismuth, manganese/pentanedione naphthenate, manganese octoate, vanadium acetylacetonate, zinc acetylacetonate, tin neodecanoate, stannous 2-ethylhexanoate, lithium neodecanoate, stannous chloride, stannous octoate, zinc naphthenate, zinc octoate, iron acetylacetonate, zinc acetylacetonate, cobalt octoate, zirconium acetylacetonate, zirconium octoate, versalate zirconium, aluminum acetylacetonate, mercury acetate, mercury phenylacetate, mercury phenylpropionate, organic mercuric compounds, and crown ether complexes of lanthanide metals. Many of these catalysts are commercially available, and commercial mixtures of catalysts useful in the present invention include Cocure, Cotin, and Coscat catalysts (cassem, Inc.); niax catalyst (Union Carbide); polycat catalyst (abbott laboratories); dabco catalyst (Air Products and Chemicals Inc.); thancat catalyst (Texaco Chemical Co.); stanclere TL (AKZO Chemicals Inc.); K-Kat catalyst (King Industries), Curene catalyst (Anderson Development Co.); bunab 600 catalyst (buckman laboratories, Inc.); optical Part 14x (PolyTech development Corp.); metasol catalyst (Calgon Corporation); CC-1 and CC-3 catalysts (Cardinal Carolina Corp.); conacure catalyst (Conap, Inc.); cata-check catalyst (Ferro Corp.); KR catalyst (KenrichPetrochemicals, Inc.); BiCAT catalyst (Shepherd Chemical Co.); texacat, ZR, ZF, DD, DMDEE catalyst (Texaco Chemical Co.); thor 535 catalyst (Thor Chemicals, Inc.); toyocat catalyst (Tosoh USA, Inc.).

In some embodiments, the catalyst is present in the coating composition of the present invention in an amount of up to 10 weight percent, such as from 0.02 to 5 weight percent, or in some cases from 0.08 to 2 weight percent, where the weight percent is based on the total weight of the coating composition. In contrast, in other embodiments, the coating compositions of the present invention are substantially free of such a catalyst, or in some cases, completely free of such a catalyst.

In some embodiments, the coating compositions of the present invention include a moisture scavenger, for example, to purposely reduce the presence of excess water during the stage of forming the coating composition, for example, where excess water is not desired. Suitable moisture scavenging components include those such as calcium compounds, e.g., CaSO₄·1/2H₂O, and calcium-metal alkoxides, such as tetraisopropyl titanate, tetra-n-butyl titanate-silane, QP-5314, vinyl silane (a171), and organoalkoxy compounds, such as triethyl orthoformate, methyl orthoformate, dimethoxypropane.

In some embodiments, the moisture scavenger is present in the coating composition of the present invention in an amount of up to 10 weight percent, such as from 0.25 to 5 weight percent, or in some cases from 0.5 to 2 weight percent, where the weight percent is based on the total weight of the coating composition. In contrast, in other embodiments, the coating compositions of the present invention are substantially free of such a moisture scavenger, or in some cases, completely free of such a moisture scavenger.

In addition, other ingredients that may be used to form the coating compositions of the present invention include water, solvents, plasticizers, extenders, fillers, hydrocarbon resin modifiers, and various types of additives such as UV stabilizers, pigment wetting agents, flow and leveling additives, thixotropic agents, defoamers, and the like.

The source of water in the coating composition of the present invention may be, for example, from the reaction between the ingredients, atmospheric humidity, and water present in one or more of the ingredients. Depending on the particular curing conditions, such as the use of the composition in a dry environment where curing occurs at ambient temperature conditions, water may be added during the formation of the composition to accelerate curing.

In some embodiments, the coating compositions of the present invention include sufficient water to accelerate the deblocking of any curing agent present in the form of a ketimine or aldimine for subsequent crosslinking, and/or to hydrolyze any alkoxy functionality within any alkoxy-functional silicone, silane component, and/or curing agent provided in the form of an aminosilane.

An organic solvent may be added as necessary. Suitable solvents include, for example, esters, ethers, alcohols, ketones, glycols, and the like. In some embodiments, the coating composition of the present invention comprises up to 25 weight percent organic solvent based on the total weight of the coating composition.

In some embodiments, the coating composition of the present invention includes a colorant. The term "colorant" as used herein refers to any substance that imparts color and/or other opacity and/or other visual effect to the composition. The colorant can be added to the coating in any suitable form, such as discrete particles, dispersions, solutions, and/or flakes. A single colorant or a mixture of two or more colorants can be used in the coating composition of the present invention.

Examples of colorants include pigments, dyes, and toners, such as those used in the paint industry and listed in the Dry Color Manufacturers Association (DCMA), as well as combinations of specific effects. The colorant may comprise, for example, a finely divided solid powder that is insoluble but wettable under the conditions of use. The colorant may be organic or inorganic and may or may not be aggregated. The colorant may be incorporated into the coating composition by using a grind vehicle (e.g., an acrylic grind vehicle), the use of which is familiar to those skilled in the art.

Examples of pigments and/or pigment compositions include, but are not limited to, carbazole dioxazine crude pigment, azo, monoazo, disazo, naphthol AS, salts (lakes), benzimidazolone, condensation, metal complexes, isoindolinone, isoindoline and polycyclic phthalocyanine, quinacridone, perylene, peryleneone, diketopyrrolylpyrrole, thioindigo, anthraquinone, indanthrone, anthrapyrimidine yellow, flavanthrone, pyranthrone, tripheno [ cd, jk ] pyrene-5, 10-dione, dioxazine, triarylcarbonium, quinophthalone pigments, diketopyrrolopyrrole red ("DPPBO red"), titanium dioxide, carbon black, and mixtures thereof. The terms "pigment" and "colored filler" are used interchangeably.

Exemplary dyes include, but are not limited to, solvent and/or aqueous based dyes such as phthalocyanine green or blue, iron oxide, bismuth vanadate, anthraquinone, perylene, aluminum, and quinacridone.

Examples of hueing agents include, but are not limited to, pigments dispersed in an aqueous-based carrier or water-miscible carrier, such as AQUA-CHEM 896, commercially available from Degussa, inc., CHARISMA COLORANTS and maxi absorbent COLORANTS, commercially available from Accurate Dispersions division of Eastman Chemical, inc.

As noted above, the colorant may be in the form of a dispersion, including, but not limited to, a nanoparticle dispersion. The nanoparticle dispersion may include one or more highly dispersed nanoparticle colorants and/or colorant particles that produce a desired visual color and/or opacity and/or visual effect. Nanoparticle dispersions can include colorants, such as pigments or dyes having a particle size of less than 150 nanometers, such as less than 70 nanometers, or less than 30 nanometers. Nanoparticles can be produced by milling raw organic or inorganic pigments with a milling media having a particle size of less than 0.5 mm. Exemplary nanoparticle dispersions and methods for their preparation are disclosed in U.S. patent No.6875800B2, which is incorporated herein by reference. Nanoparticle dispersions can also be produced by crystallization, precipitation, gas phase condensation, and chemical abrasion (i.e., partial dissolution). To minimize re-aggregation of the nanoparticles within the coating, a dispersion of resin-coated nanoparticles may be used. As used herein, "dispersion of resin-coated nanoparticles" refers to a continuous phase having dispersed therein discrete "composite particles" comprising nanoparticles and a resin coating on the nanoparticles. Exemplary dispersions of resin-coated nanoparticles and methods for their preparation are disclosed in U.S. patent application publication 2005-0287348a1, filed 24.6.2004, U.S. provisional application No. 60/482167, filed 24.6.2003, and U.S. patent application serial No. 11/337062, filed 20.1.2006, which are also incorporated herein by reference.

Examples of special effect compositions that may be used in the compositions of the present invention include pigments and/or compositions that produce one or more appearance effects, such as reflectance, pearlescence, metallic sheen, phosphorescence, fluorescence, photochromism, photosensitivity, thermochromism, goniochromism and/or color change. Additional special effect compositions may provide other perceptible properties, such as opacity or texture. In some embodiments, the special effect composition may produce a color shift such that the color of the coating changes when the coating is viewed from different angles. Examples of color effect compositions are disclosed in U.S. patent No.6894086, which is incorporated herein by reference. Additional color effect compositions can include transparent coated mica and/or synthetic mica, coated silica, coated alumina, transparent liquid crystal pigments, liquid crystal coatings, and/or any composition in which interference results from differences in refractive index within the material rather than differences in refractive index between the surface of the material and the air.

In general, the colorant can be present in any amount sufficient to impart the desired visual and/or color effect. The colorant can constitute, for example, 1 to 65 weight percent, such as 3 to 40 weight percent or 5 to 35 weight percent, of the weight of the composition of the present invention, where the weight percent is based on the total weight of the composition.

In some embodiments, the compositions of the present invention comprise a finely divided particulate filler. Examples of fillers that provide high heat resistance are barite (barium sulfate), mica, micaceous iron ore, aluminum flakes, glass flakes, stainless steel flakes, and the like. Some embodiments of the coating composition of the present invention include up to 10 weight percent filler, based on the total weight of the composition.

In some embodiments, the coating compositions of the present invention are substantially free, or in some cases, completely free, of any acrylic resin.

As previously mentioned, in some embodiments, the coating compositions of the present invention are supplied in a two-component or two-pack system, for example, in a moisture-proof container. In general, the "a" part or first package or component includes an alkoxy-functional and/or silanol-functional silicone and an epoxy-functional silicone; and "B" part or second package or component includes a curing agent.

In some embodiments, any curing agent provided in the form of a ketimine or aldimine deblocks to expose amine functionality when the two components or packages are combined in the presence of water. The alkoxy-functional and/or silanol-functional silicones, any silanes and any curing agents in the form of alkoxy-containing aminosilanes undergo hydrolysis in the presence of water and condensation polymerization with themselves and with each other.

To the extent that the polycondensation product includes amine functionality, the amine functionality, as well as any free aminosilane, may be adducted with epoxy-functional ingredients within the coating composition.

The combined ingredients used to form the coating compositions of the present invention are often provided in moisture-resistant containers to control or prevent unwanted evaporation and/or hydrolysis and condensation of the constituent chemical components, thereby increasing the life of the mixture. Sealed metal cans are suitable.

The composition of the present invention may be applied to the desired substrate surface to protect it from weather, impact, and exposure to corrosion and/or chemicals. Exemplary substrates that can be treated with the compositions of the present invention include wood, plastic, concrete, vitreous surfaces, and metal surfaces. The compositions of the present invention may be used, for example, as a topcoat disposed directly on the substrate surface itself or on a previous or other base coating disposed on the substrate surface, such as an inorganic or organic primer material, to achieve a desired purpose.

The compositions of the present invention may be applied to the surface to be treated by conventional coating techniques such as dip coating, direct roll coating, reverse roll coating, curtain coating, spray coating, brush coating and combinations thereof, and are sometimes applied as a film of 50 to 250 micrometers, or in some embodiments, up to 1.2 millimeters in thickness. If desired, multiple layers may be applied to the surface to be protected. For use with wood substrates, such as in the furniture industry, dried films of 75-125 microns thickness sometimes provide the desired degree of protection of the underlying surface.

The coating compositions of the present invention can be formulated to provide the desired drying and curing times under a wide range of temperature conditions, for example under elevated temperature conditions, such as when the applied composition is subjected to baking conditions, and under ambient temperature conditions, for example when the applied composition is subjected to temperature conditions that can and will vary with the temperature of the surrounding environment (for example it may vary between 5-50 ℃).

As will be appreciated, in some embodiments, the coating compositions of the present invention may be embodied in the form of a kit. Such a kit may comprise: (a) a silicone containing (i) an alkoxy-functional and/or silanol-functional group; (ii) an epoxy-functional silicone; and (iii) a hydroxyl-functional and/or epoxy-functional component different from (i) and (ii); and (b) a second container containing a curing agent.

Additionally, as understood from the foregoing disclosure, the silicone may be prepared by combining, inter alia, (a) alkoxy-functional and/or silanol-functional silicones; (b) an epoxy-functional silicone; (c) a curing agent, and one or more of the optional components previously described, to prepare the coating composition of the present invention.

The following examples illustrate the invention and are not to be construed as limiting the invention to the details thereof. All parts and percentages in the examples, as well as throughout the specification, are by weight unless otherwise indicated.

Example 1

Coating compositions were prepared using the components and amounts described in table 1. Part a was prepared by combining components 1-8 in a1 quart jar. The can containing the mixture was then placed on a Hockmeyer mixer equipped with a Cowles blade. The pigment was dispersed to a fineness of pulverization of 6 blackgman (hegman), and the thixotropic agent was activated by dispersing the mixture at a high speed for 30 minutes. During this time, the temperature rose from 23 ℃ to about 75 ℃. The temperature was then reduced to 55 ℃ before addition of components 9-16. The combined mixture was then mixed until homogeneous. At this point, component 17 was sieved into the stirred mixture over 15 minutes. After addition of component 17, stirring was continued for another 10 minutes to ensure homogeneity. Part A had a Brookfield viscosity of 6000cP at 25 deg.C and a calculated epoxy equivalent of 1318.99 g/eq.

Part B was prepared by combining components 18-22 in a1 quart jar. The mixture was stirred with a metal spatula until homogeneous, which required less than 5 minutes. Part B has a calculated amine equivalent of 167.4 g/equivalent and a Brookfield viscosity of less than 10cP at 25 ℃. TABLE 1¹Cycloaliphatic epoxy resins commercially available from Asahi Denka.²A surfactant commercially available from Rhodia.³Pigment wetting agents commercially available from Byk Chemie.⁴Defoamers commercially available from Ultra Additives.⁵Titanium dioxide commercially available from Huntsman.⁶Nephene ortholite commercially available from Unimin Specialty Minerals.⁷Para-tert-butyl ether solvent commercially available from Lyondell.⁸Thixotropic agents commercially available from King Industries.⁹Epoxy functional silicone resins commercially available from Momentive Performance Chemicals.¹⁰Amine light stabilizers commercially available from Ciba.¹¹Flow additives commercially available from Dow Corning.¹²Leveling additives commercially available from Byk Chemie.¹³Solvents commercially available from Eastman.¹⁴Ethoxyethyl propionate, commercially available from Eastman.¹⁵Methoxy functional silicone resins commercially available from Dow Corning.¹⁶Antifoam commercially available from Byk Chemie.¹⁷Silica matting pigments commercially available from Grace.¹⁸Aminoneohexylmethyldiethoxysilane commercially available from Momentive Performance Chemicals.¹⁹Aminopropyl triethoxy commercially available from Shin-EtsuA silane.²⁰Aminopropyl trimethoxysilane, commercially available from Shin-Etsu.²¹Dibutyl tin diacetylacetonate commercially available from Kaneka America.²²A solvent commercially available from Chevron.

Example 2

Coating compositions were prepared using the components and amounts described in table 2. Part a was prepared by combining components 1-8 in a1 quart jar. The can containing the mixture was then placed on a Hockmeyer mixer equipped with a Cowles blade. The pigment was dispersed to a pulverization fineness of 6 blackgman, and the thixotropic agent was activated by dispersing the mixture at a high speed for 30 minutes. During this time, the temperature rose from 23 ℃ to about 77 ℃. The temperature was then reduced to 55 ℃ before addition of components 9-16. The combined mixture was then mixed until homogeneous. At this point, component 17 was sieved into the stirred mixture over 15 minutes. After addition of component 17, stirring was continued for another 10 minutes to ensure homogeneity. Part A had a Brookfield viscosity of 6500cP at 25 deg.C and a calculated epoxy equivalent of 1218.25 g/eq.

Part B was prepared by combining components 18 and 19 in a1 quart can. The mixture was stirred with a metal spatula until homogeneous, which required less than 5 minutes. The calculated amine equivalent of part B was 119.0 g/equivalent, and the Brookfield viscosity at 25 ℃ was less than 10 cP. TABLE 2²³Urethane acrylate oligomers commercially available from Cognis.

Example 3

Combine 200.0g (0.1516 equiv.) of part A of example 1 with 29.66g (0.1771 equiv.) of part B of example 1. The mixture was sprayed on the test panel using a Devilbiss air atomizing spray gun. Grit blasted steel panels (4 "x 7" x 1/16 ") with a 2-mil profile (profile) were used for tapered mandrel elongation. Aluminum panels (3 ". times.6") were used for the QUV-B accelerated weathering test. Hardiplank cement fiber composite panels (4 ". times.6") were used for Florida weathering and cycling QUV-B/Freeze/Cleveland humidity exposure tests. The thickness of the dried film ranged from 0.004 to 0.005 inches on all test panels.

Example 4

Combine 200.0g (0.1641 equiv.) of part A of example 2 with 30.86g (0.1843 equiv.) of part B of example 1. The mixture was applied using the same spray equipment and test panel as described in example 3. The thickness of the dried film ranged from 0.004 to 0.005 inches on all test panels.

Example 5

Combine 200.0g (0.1641 equivalents) of part A of example 2 with 22.46g (0.1887 equivalents) of part B of example 2. The mixture was applied using the same spray equipment and test panel as described in example 3. The thickness of the dried film ranged from 0.004 to 0.005 inches on all test panels.

The results are shown in Table 3. TABLE 3

Test of	Example 3	Example 4	Example 5
				Dry to touch, wet thickness 6 mil, hour (ASTM D1640)	0.5-1.0	0.5-1.0	2.0-3.0

Total dry, wet thickness 6 mil, hour (ASTM D1640)	5.0-6.0	5.0-6.0	6.0-7.0
				Elongation of tapered mandrel (ASTM D-522) after 3 days at 25 ℃ and 11 days at 60 ℃	4.5％	4.5％	0％
QUV-B accelerated weathering (ASTM G53) after 60 ℃ gloss-onset-4400 hours	6.04.5	8.05.0	8.05.0
				Florida weathering, 60 ℃ gloss-onset-after 6 weeks	3.63.5	7.56.4	-
Cycle exposure test (1 cycle 7 days QUV-B, 0 ℃ 2 days, Cleveland humidity 5 days) after 8 cycles	Without bubble cracking or loss of adhesion	Without bubble cracking or loss of adhesion	-

The drying time, conical mandrel elongation and weathering data show that the composition of the invention (example 3) can have the same fast cure time and flexibility and comparable or better weathering properties compared to the prior art composition of example 4, which is based on epoxy resin, alkoxy or silanol functional silicone resin and acrylate oligomer.

The tapered mandrel elongation data for examples 3 and 4 are significantly higher than the tapered mandrel elongation data for example 5. This shows that the preferred aminosilane curing agents of the present invention provide improved flexibility compared to the prior art.

It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.

Claims (18)

1. A coating composition comprising:

(a) an alkoxy-functional and/or silanol-functional silicone comprising a compound represented by the general formula:

wherein

(a-i) each R₁Can be the same or different and are selected from hydroxyl, alkyl having up to 6 carbon atomsAn aryl group having up to 6 carbon atoms, and an alkoxy group having up to 6 carbon atoms;

(a-ii) each R₂Which may be the same or different, are selected from hydrogen, alkyl groups having up to 6 carbon atoms, and aryl groups having up to 6 carbon atoms; and

(a-iii) selecting n such that the silicone has a weight average molecular weight in the range of 400-10,000;

(b) an epoxy-functional silicone represented by one of the following general structures,

wherein m is an integer having a value ranging from 1 to 10,000;

n is an integer having a value in the range of 1 to 100;

and each X, which may be the same or different, represents an epoxy-containing group; and

(c) and (3) a curing agent.

2. The coating composition of claim 1, wherein the epoxy-functional silicone comprises two or more epoxy functional groups.

3. The coating composition of claim 2, wherein the epoxy-functional silicone comprises two epoxy functional groups.

4. The coating composition of claim 1, wherein the at least one epoxy-containing group is represented by one of the following structures:

5. the coating composition of claim 1, wherein the epoxy-functional silicone is represented by the general formula:

wherein

(a) Each R³May be the same or different and is an alkylene group having 1 to 18 carbon atoms, or an arylene group;

(b) each R⁴Which may be the same or different, are alkyl groups, aryl groups, vinyl groups, glycols, alkoxy groups containing 1 to 8 carbon atoms, or epoxy groups; and

(c) n is greater than or equal to 1.

6. The coating composition of claim 1, wherein (a) and (b) are present in the composition in a weight ratio of at least 1: 1.

7. The coating composition of claim 1, wherein the curing agent comprises a compound of the formula Y-Si- (O-X)₃An aminosilane of, wherein

(a) Each X, which may be the same or different, is an alkyl, hydroxyalkyl, alkoxyalkyl or hydroxyalkoxyalkyl group having less than 6 carbon atoms; and

(b) y is H (HNR)_cWherein

(b-i) c is an integer having a value of 1 to 6; and

(b-ii) each R is a difunctional organic group independently selected from the group consisting of aryl, alkyl, dialkylaryl, alkoxyalkyl and cycloalkyl groups, wherein R can vary within each Y molecule.

8. The coating composition of claim 1, wherein the curing agent comprises a compound of the formula BR_eSi(OR³)_3-eThe aminosilane of (1), wherein:

(a) b is a compound of the formula-CR² ₂A group of-Y, wherein

(a-i)R²Is hydrogen or alkyl having 1 to 4 carbon atoms, and

(a-ii) Y is a nitrogen atom-containing group;

(b)R³is an alkyl group having 1 to 8 carbon atoms; and

(c) e is 0, 1 or 2.

9. The coating composition of claim 8, wherein the curing agent comprises cyclohexylaminomethyl methyldiethoxysilane.

10. The coating composition of claim 1, further comprising:

(d) a hydroxy-functional and/or epoxy-functional component different from (a) and (b).

11. The coating composition of claim 1, further comprising:

(d) an epoxy functional component different from (a) and (b).

12. The coating composition of claim 11, wherein the epoxy functional component comprises an epoxy resin having more than one 1, 2-epoxy group per mole.

13. The coating composition of claim 11, comprising:

5 to 80 wt% of component (a);

5 to 80 wt% of component (b);

1 to 30 wt% of component (c); and

1 to 50 wt% of component (d).

14. The coating composition of claim 11, further comprising:

(e) silane;

(f) an amine reactive component selected from the group consisting of acetoacetate functional component, acrylate functional component, and mixtures thereof;

(g) an elastomer resin;

(h) a silicon-containing polyether;

(i) a silicone fluid; and/or

(j) An organic halogen-containing component.

15. The coating composition of claim 1, further comprising an organometallic catalyst.

16. The coating composition of claim 1, wherein the coating composition is in the form of a two-component coating composition comprising:

(1) a first component comprising components (a) and (b); and

(2) a second component comprising component (c).

17. The coating composition of claim 16, wherein the first component further comprises a hydroxy-functional and/or epoxy-functional ingredient different from components (a) and (b).

18. A substrate at least partially coated with a coating deposited from the coating composition of claim 1.