WO2024057235A1

WO2024057235A1 - Multi-surface coating composition

Info

Publication number: WO2024057235A1
Application number: PCT/IB2023/059096
Authority: WO
Inventors: Martín LÓPEZ MARTÍNEZ; Rafael GARCÍA GONZÁLEZ; Llulisa MORENO RAMOS; Dulce Anahí GARCÍA RIVERO; Jorge Alberto Escobar Ramírez; Jesús Guadalupe HERRERA VAZQUEZ; Julio Jesus ENCISO TENORIO
Original assignee: Consorcio Comex, S.A. De C.V.
Priority date: 2022-09-16
Filing date: 2023-09-13
Publication date: 2024-03-21

Abstract

Disclosed is a multi-surface coating composition that can function as a primer and paint in a single composition. The coating composition includes (A) a first emulsion and optionally (B) a second emulsion. The first emulsion includes a polymer formed from components comprising (i) monomers comprising (a) a (meth)acrylate monomer, (b) an aromatic monomer having an ethylenically unsaturated group, and (c) a (meth)acrylamide monomer, and (ii) optionally, a first coalescent. The coating composition can also include (C) a crosslinking agent reactive with the (meth)acrylamide monomer.

Description

MULTI-SURFACE COATING COMPOSITION

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of United States Provisional Application Serial No. 63/375,911, filed September 16, 2022, and titled “Multi-Surface Coating Composition,” which is incorporated herein by reference in its entirety.

BACKGROUND

Technical Field

[0002] This disclosure relates to a multi-surface coating composition that can be applied to a variety of substrates.

Related Technology

[0003] Coatings are applied to a variety of substrates. Often, coatings are applied to surfaces of architectural structures to protect the surfaces from the environment, to provide color and aesthetic enhancement, to provide corrosion resistance, or to provide abrasion resistance. Typically, on these and other substrates, a primer is first added to the substrate surface. The primer is intended to enhance adhesion of the subsequently added paint layer by adhering to the substrate surface and forming a binding layer better prepared to receive the paint. The paint layer is applied following sufficient curing of the primer.

[0004] The application of multiple coating layers to architectural substrates and other substrates can be relatively time and effort intensive. Not only is it more time intensive to apply multiple layers, but the user must also wait a sufficient time between layers to allow proper curing. For example, a primer layer should be allowed to cure before subsequent application of a paint layer.

[0005] Coatings, once applied and cured, can suffer various optical and/or physical defects. For example, a coating with a gloss finish can lose gloss, or the coating can suffer from discoloration. For example, a coating with a white pigment (or similar light color) can suffer from yellowing. If adhesion to the underlying substrate is insufficient, a coating is more likely to fracture, peel, and/or delaminate. Coatings with insufficient dirt pickup resistance (DPUR; the ability of a surface to resist discoloration due to the deposition of particles from the environment) can accumulate particles from the environment, resulting in discoloration. In exterior architectural applications in particular, particulates, pollution, and corrosion can cause and/or accelerate optical and physical defects in coatings.

BRIEF SUMMARY

[0006] Disclosed herein is a multi-surface coating composition that can function as a primer and paint in a single composition. The coating composition includes (A) a first emulsion and optionally (B) a second emulsion. The first emulsion includes a polymer formed from components comprising (i) monomers comprising (a) a (meth) acrylate monomer, (b) an aromatic monomer having an ethylenically unsaturated group, and (c) a (meth)acrylamide monomer, and (ii) optionally, a first coalescent. The coating composition can also include (C) a crosslinking agent reactive with the (meth)acrylamide monomer.

[0007] The (meth) acrylate monomer can include an alkyl (meth) acrylate, such as an alkyl methacrylate (e.g., methyl methacrylate), and/or can include a dialkyl acrylate, such as 2-ethylhexyl acrylate. The aromatic monomer having an ethylenically unsaturated group can include styrene. The (meth)acrylamide monomer can include a ketone (meth) acrylamide, such as diacetone acrylamide. The first coalescent can include an ester of a glycol (such as a monoester of a glycol) and/or an ether of a glycol. The optional second emulsion can be different from the first emulsion. The optional second emulsion can be a (meth)acrylic emulsion, such as a styrene (meth)acrylic emulsion.

[0008] Also disclosed herein is a method for coating a substrate by applying the disclosed coating composition to at least a portion of the substrate. Also disclosed herein is a substrate coated at least in part with the disclosed coating composition.

[0009] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an indication of the scope of the claimed subject matter.

DETAILED DESCRIPTION

[0010] Disclosed herein is a multi-surface coating composition that can function as a primer and paint in a single composition. The coating composition includes (A) a first emulsion and optionally (B) a second emulsion. The first emulsion includes a polymer formed from components comprising (i) monomers comprising (a) a (meth) acrylate monomer, (b) an aromatic monomer having an ethylenically unsaturated group, and (c) a (meth)acrylamide monomer, and (ii) optionally, a first coalescent. The coating composition can also include (C) a crosslinking agent reactive with the (meth)acrylamide.

[0011] As used herein, an “emulsion” is a mixture of polymer particles within an aqueous medium. A mixture of polymer particles within an aqueous medium is technically a “dispersion,” though the term “emulsion” is commonly used in the art and both terms are used accordingly herein. The term “emulsion” may be used synonymously with the term “latex.”

[0012] Also disclosed herein is a method for coating a substrate by applying the disclosed coating composition to at least a portion of the substrate. Also disclosed herein is a substrate coated at least in part with the disclosed coating composition.

[0013] The substrate may be, for example, an architectural substrate, such as a roof, metal structures, exterior wall, or interior wall (including ceilings). Example substrates to which the disclosed coating composition may be applied include, but are not limited to: metal, such as carbon steel, aluminum, or galvanized steel; ceramic, such as ceramic tile; a masonry surface, such as brick, stone, or concrete; drywall; and/or wood.

[0014] The coating composition can beneficially exhibit effective adhesion properties and corrosion resistance without sacrificing optical properties. First Emulsion

[0015] The polymer of the first emulsion can be formed from monomers comprising (meth)acrylate monomers. The (meth) acrylate monomers can comprise alkyl (meth) acrylate monomers, such as alkyl methacrylate monomers (e.g., methyl methacrylate monomers) and/or alkyl acrylate monomers such as butyl acrylate and isobutyl acrylate, and including dialkyl acrylate monomers such as 2-ethylhexyl acrylate monomers.

[0016] The terms “(meth) acrylic” or “(meth) acrylate” are intended to cover both the acrylic/acrylate and methacrylic/methacrylate forms of the indicated material. For example, (meth) acrylate monomers can include acrylate monomers (without the methyl substitution) and/or methacrylate monomers. Further, a “(meth) acrylic” or “(meth)acrylate” compound/material is inclusive of acrylic acid forms, acrylic acid anhydride forms, and derivatives thereof. Such derivatives include C1-C5 alkyl esters of acrylic acids, lower alkyl-substituted acrylic acids (e.g., Ci- C2 substituted acrylic acids, such as methacrylic acid and/or ethacrylic acid), and Ci- Cs alkyl esters of lower alkyl-substituted acrylic acids (e.g., methyl methacrylate). The “acrylic” and “acrylate” forms of such compounds/materials are used interchangeably herein unless specified otherwise.

[0017] The (meth) acrylate monomers may be included at a concentration of 40% to 90%, such as 60% to 80%, based on total weight of monomers used for the first emulsion. For example, the first emulsion can include an alkyl methacrylate, such as methyl methacrylate, at a concentration of 25% to 45%, such as 30% to 40%, based on total weight of monomers used for the first emulsion, and/or a dialkyl acrylate, such as 2-ethylhexyl acrylate, at a concentration of 15% to 45%, such as 30% to 40%, based on total weight of monomers used for the first emulsion.

[0018] The polymer of the first emulsion can be formed from monomers comprising aromatic monomers having an ethylenically unsaturated group, such as styrene. The aromatic monomer having an ethylenically unsaturated group can be included at a concentration of 20% to 30% based on total weight of monomers used for the first emulsion. As used herein, “ethylenically unsaturated” refers to a group having at least one carbon-carbon double bond. [0019] The polymer of the first emulsion can be formed from monomers comprising a (meth) acrylamide monomer, such as a ketone (meth) acrylamide, such as diacetone acrylamide. The (meth) acrylamide monomer can be included at a concentration of 0.5% to 3%, such as 0.75% to 2%, or 1% to 1.5%, based on total weight of monomers used for the first emulsion.

[0020] An “acrylamide” replaces the hydroxy group of an acrylic acid (or the deprotonated oxygen of an acrylate) with an amine. Similar to the terms “(meth)acrylic” and “(meth)acrylate,” the term “(meth)acrylamide” can include acrylamide monomers (without the methyl substitution) and/or methacrylamide monomers. Further, a “(meth) acrylamide” compound/material is inclusive of derivatives such as N-(Ci-Cs alkyl) amides thereof (e.g., N-methyl acrylamide), lower alkyl-substituted acrylamides (e.g., C1-C2 substituted acrylamides, such as methacrylamide and/or ethacrylamide), and N-(Ci-Cs alkyl) amides of lower alkylsubstituted acrylamides (e.g., N-methyl methacrylamide).

[0021] The first emulsion can include a dicarboxylic acid, such as itaconic acid. The dicarboxylic acid may be included at a concentration of 0.25% to 2%, such as 0.5% to 1.5%, by total weight of monomers used for the first emulsion.

[0022] The polymer and/or solids content of the first emulsion can make up 15% to 65% of the total weight of the first emulsion. The first emulsion can comprise an aqueous medium. An “aqueous medium” refers to a liquid medium comprising at least 50% water, based on the total weight of the liquid medium. Such aqueous liquid mediums can comprise at least 60% water, or at least 70% water, or at least 80% water, or at least 90% water, or at least 95% water, based on the total weight of the liquid medium. The solvents that make up less than 50% of the liquid medium can include organic solvents. Non-limiting examples of suitable organic solvents include polar organic solvents (e.g., protic organic solvents such as glycols, glycol ether alcohols, alcohols, and volatile ketones, glycol diethers, esters, and diesters). Other non-limiting examples of organic solvents include aromatic and aliphatic hydrocarbons.

[0023] Polymer particles of the first emulsion can have a particle size (volume basis) of 110 nm to 150 nm, such as 120 nm to 140 nm or 125 nm to 135 nm, or any other range combination using the foregoing as endpoints, as measured using dynamic light scattering (DLS). Emulsions with particle sizes within the foregoing ranges were beneficially found to balance optical properties and stability of the coating composition. For example, a particle size too low can compromise stability, whereas a particle size too high can compromise the gloss properties of the coating composition. A first emulsion with a particle size within the foregoing ranges can beneficially provide effective stability without compromising optical properties such as gloss.

Crosslinking Agent

[0024] The coating composition can include a crosslinking agent reactive with the (meth) acrylamide groups of the polymer of the first emulsion. Example crosslinking agents include, but are not limited to, dihydrazides, such as adipic dihydrazide, polyamines, or combinations thereof.

[0025] The crosslinking agent may be included in an amount that is 30% to 70%, such as 40% to 60%, of the amount of (meth)acrylamide monomers, by weight, and/or in an amount that is at least molar equivalent to the amount of (meth)acrylamide monomer used. A “molar equivalent” refers to a concentration or amount at which the number of crosslinking agent molecules is essentially equivalent to the number of (meth) acrylamide monomer molecules used. The skilled person is readily equipped to convert molar values to weight amounts or weight percentages and vice versa.

[0026] The crosslinking agent and (meth) acrylamide groups beneficially function as a self-crosslinking system that reacts during film formation and that can enhance the mechanical resistance and adhesion properties of the coating composition.

[0027] Scheme 1 shows an example crosslinking system in which the (meth) acrylamide is diacetone acrylamide and the crosslinking agent is adipic dihydrazide. Scheme 1

Cross-Linking

[0028] Scheme 2 shows an example crosslinking system in which the (meth) acrylamide is diacetone acrylamide and the crosslinking agent is a polyethylenimine (PEI).

Scheme 2

Coalescent

[0029] The polymer of the first emulsion can optionally include a first coalescent, such as an ester of a glycol (e.g., a monoester of a glycol), and/or an ether of a glycol. For example, the first coalescent can comprise a monoester of (i) a glycol and (ii) a butyric acid or an isobutyric acid, such as 2,2,4-trimethyl-l,3-pentanediol monoisobutyrate, and/or can comprise a propylene glycol ether, such as dipropylene glycol mono n-butyl ether.

[0030] The coating composition can optionally include a second coalescent. For example, the second coalescent may be included in addition to or as an alternative to the first coalescent. The second coalescent may be the same as or different from the first coalescent. The second coalescent can be included within the coating composition but not used to form the polymer of the first emulsion of the coating composition. [0031] For example, the polymer of the first emulsion may omit or essentially omit the first coalescent, and the second coalescent may be included in the coating composition separate from the polymer of the first emulsion. Alternatively, the polymer of the first emulsion may include the first coalescent, and the coating composition may omit or essentially omit a second coalescent. Alternatively, the polymer of the first emulsion may include the first coalescent and the coating composition may include the second coalescent separate from the polymer of the first emulsion.

[0032] Including at least a portion of the total amount of coalescent of the coating composition in the polymer of the first emulsion was beneficially found to improve stability of the coating composition and to avoid unwanted lump formation. For example, of the total amount, by weight, of coalescent included in the coating composition, 20% to 90%, such as 35% to 85%, or 30% to 80%, or 35% to 80%, or any range combination using the foregoing as endpoints, may be in the form of the second coalescent (i.e. , included in the coating composition separate from the polymer of the first emulsion).

[0033] The combined total of the first coalescent and/or second coalescent may be 1% to 15%, such as 1% to 12%, or 1% to 10%, or 1% to 9%, or any other range combination using the foregoing as endpoints, by total weight of the coating composition.

[0034] The first emulsion, when omitting or essentially omitting the first coalescent, may have a glass transition temperature (Tg) of 20° C to 35° C, such as 25° C to 30° C, as measured by differential scanning calorimetry (DSC). The first emulsion, when including the first coalescent, may have a Tg of 0° C to 10° C, such as 2° C to 8° C, as measured by DSC.

Second Emulsion

[0035] The coating composition can optionally include a second emulsion. The second emulsion can be different than the first emulsion. The second emulsion can be a (meth)acrylic resin emulsion, such as a styrene (meth)acrylic resin emulsion. That is, the second emulsion can include a polymer formed from components comprising (meth) acrylate monomers, such as styrene (meth)acrylic monomers. [0036] (Meth)acrylic monomers used for the second emulsion can be polymerized by themselves or with vinyl monomers such as vinyl aromatic monomers and allylic monomers. Examples of vinyl monomers include vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrates, vinyl benzoates, vinyl isopropyl acetates, and similar vinyl esters. Vinyl halides include vinyl chloride, vinyl fluoride, and vinylidene chloride. Vinyl aromatic hydrocarbons include styrene, methyl styrenes, and similar lower alkyl styrenes, chlorostyrene, vinyl toluene, vinyl naphthalene, divinyl benzoate, and cyclohexene. Vinyl aliphatic hydrocarbon monomers include alpha olefins such as ethylene, propylene, isobutylene, and cyclohexyl as well as conjugated dienes such as butadiene, methyl-2-butadiene, 1,3-piperylene, 2,3- dimethyl butadiene, isoprene, cyclopentadiene, and dicyclopentadiene. Vinyl alkyl ethers include methyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, and isobutyl vinyl ether. Examples of allylic monomers include allyl alcohol and allyl chloride.

[0037] The polymer and/or solids of the second emulsion can make up 15% to 65% of the total weight of the first emulsion. The optional second emulsion can be included in an amount that gives a first emulsion to second emulsion ratio (by weight) of 0.25:1 to 1.5:1, such as 0.3:1 to 1:1, or 0.35:1 to 0.7:1.

[0038] The second emulsion can comprise an emulsion commercially available under the trade name MAINCOTE™ HG-100 Emulsion (available from Dow Chemical Company, Midland, MI) and/or under the trade name AVANSE™ MV-100 (available from Dow Chemical Company, Midland, MI).

Other Coating Composition Components

[0039] The coating composition can include other components. Such other components may include, for example, fillers, pigments, non-aqueous co-solvents such as ethylene glycol, wetting agents, dispersants, defoamers, pH regulators, matting agents, biocides, fungicides, rheological modifiers, and/or rust inhibitors. The coating composition can include an aqueous medium as that term is defined herein.

[0040] The coating composition can omit or essentially omit certain components. For example, the coating composition may be free or essentially free of alkylphenol ethoxylates (APEOs). The coating composition may omit or essentially omit acetoacetoxyethyl methacrylate monomers. For example, acetoacetoxyethyl methacrylate monomers may be omitted or essentially omitted from the first emulsion. The coating composition may omit or essentially omit alkoxysilane. For example, alkoxysilane may be omitted or essentially omitted from the first emulsion.

Example Functional Properties

[0041] The coating composition, when cured, can beneficially exhibit effective optical properties, adhesion properties, and corrosion resistance. With respect to optical properties, the coating composition, when cured, can exhibit a change in gloss (60°) after 23 days of no more than 15, such as no more than 12.5, or no more than 10, or no more than 7.5, according to ASTM D523-14(2018). Additionally, or alternatively, the coating composition, when cured, can exhibit a change in yellowing index after 23 days of no more than 2, such as no more than 1.8, according to ASTM D523-14(2018).

[0042] With respect to adhesion properties, the coating composition, when applied to at least a portion of a substrate and cured, can exhibit an adhesion rating of 3B or greater, according to ASTM D3359-22. The substrate in such functional testing can comprise aluminum, carbon steel, galvanized steel, and/or ceramic tile, for example.

[0043] With respect to corrosion resistance, the coating composition, when cured, can exhibit no more than “Few” blisters at no lower than rate 4, according to ASTM D 714-02(2017), after 96 hours continuous salt spray exposure according to ASTM B 117-19. Additionally, or alternatively, the coating composition, when cured, can exhibit a mean creepage from scribe rating of 5 or higher, according to ASTM D 1654 -08(2016), after 96 hours continuous salt spray exposure according to ASTM B 117- 19.

[0044] The ASTM D 714-02(2017) standard employs photographic reference standards to evaluate the degree of blistering that may develop when paint systems are subjected to conditions which can cause blistering. The test method provides a standard procedure of describing the size and density of the blisters, according to photographic reference standards, so that comparisons of severity can be made. The photographic reference standards illustrate two characteristics of blistering: size and frequency. With respect to size, rate 10 has no blister, rate 8 represents the smallest size blister visible to the naked eye, and rate numbers 6, 4, and 2 represent progressively larger blister sizes. With respect to frequency, the photographic reference standards designate gradations (in order of most blisters to fewest) of Dense, Medium dense, Medium, and Few.

Other Terms & Definitions

[0045] Although particular examples of coating compositions are described herein, the examples do not limit the scope of the present disclosure. For example, where specific coalescent compounds are described by way of example, it will be understood that other coalescent compounds may additionally or alternatively be used.

[0046] Unless otherwise indicated, numbers expressing quantities, proportions, percentages, or other measurements used in the specification and claims are to be understood as optionally being modified by the term “about” or its synonyms, even if the term does not expressly appear. Any numerical range recited herein is intended to include all subranges subsumed therein. When ranges are given, any endpoints of those ranges and/or numbers within those ranges can be combined within the scope of the present disclosure.

[0047] Plural use of terms encompasses singular use of the terms and vice versa. For example, while the disclosed coating composition has been described in terms of including “a” crosslinking agent and “a” (meth) acrylamide monomer, additional crosslinking agents and/or (meth) acrylamide monomers may be included.

[0048] “Including” and like terms mean “including but not limited to”. Similarly, as used herein, the terms “on”, “applied on/over”, “formed on/over”, “deposited on/over”, “overlay” and “provided on/over” a surface mean applied, formed, deposited, overlay, or provided, respectively, on but not necessarily in contact with the surface. For example, a coating layer “formed over” a substrate does not preclude the presence of one or more other coating layers of the same or different composition located between the formed coating layer and the substrate.

[0049] When the term “about,” “approximately,” “substantially,” “essentially,” or the like are used in conjunction with a stated amount, value, or condition, it may be taken to mean an amount, value, or condition that deviates by 10% or less, 5% or less, 1% or less, 0.1% or less, or 0.01% or less from the stated amount, value, or condition. For example, a recited average particle size of “about” X nm includes particle sizes that differ from X (higher or lower) by up to 10%, up to 5%, up to 1%, up to 0.1%, or up to 0.01%.

[0050] The coating composition disclosed herein should be understood as comprising/including disclosed components, and may therefore include additional components not specifically described. Optionally, the coating composition disclosed herein is essentially free or completely free of components that are not specifically described. That is, non-disclosed components may optionally be omitted or essentially omitted from the disclosed coating composition. For example, a particular monomer that is not specifically described as being included in the disclosed coating composition may be optionally excluded (i.e., essentially omitted or completely omitted).

[0051] A composition that “essentially omits” or is “essentially free of’ a component may include trace amounts and/or non-functional amounts of the component. For example, an “essentially omitted” component may be included in an amount no more than 10%, no more than 5%, no more than 2.5%, no more than 1%, no more than 0.1%, or no more than 0.01% by total weight of the composition. This is likewise applicable to other negative modifier phrases such as, but not limited to, “essentially omits,” “essentially without,” similar phrases using “substantially” or other synonyms of “essentially,” and the like.

[0052] The “weight solids content” refers to the weight of nonvolatile material of a composition divided by the total weight of the composition. The term is used synonymously herein with “nonvolatile weight” and similar terms. See ASTM D 5201-03a.

[0053] Any headings and subheadings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims.

EXAMPLES

Example 1

[0054] Test emulsions (1A-6A) were prepared with the components shown in Table 1. Values given in Table 1 are based on total weight of monomers of the emulsion. The average particle sizes (Dp), based on volume, as measured using DLS, are also shown in the Table. Coalescent (2,2,4-trimethyl-l,3-pentanediol monoisobutyrate) was added to the emulsions at 2% based on total weight of the emulsion composition.

Table 1

[0055] The emulsions were then formulated into test coating compositions 1A- 6 A. Table 2 shows components of the resulting coating compositions.

Table 2

*Percent wt. based on total weight of the coating composition.

**Percent wt. based on total nonvolatile weight of the emulsion composition; coalescent was 2, 2, 4-trimethyl- 1,3 -pentanediol monoisobutyrate.

[0056] The “other components” included additional water, pigment, defoamer, biocide, rust inhibitor, rheology modifier, dispersant, and pH regulator components customary in the art. [0057] The test coating compositions were subjected to stability testing according to ASTM DI 849-95(2019) (Standard Test Method for Package Stability of Paint). All the test compositions had acceptable performance.

[0058] The test compositions were applied on glass and their gloss was evaluated according to ASTM D523-14 (2018) (Standard Test Method for Specular Gloss). Results are shown in Table 3.

Table 3

[0059] The test compositions were also applied to ceramic tiles and their adhesion to this substrate was evaluated following ASTM D3359-22 (Standard Test Methods for Rating Adhesion by Tape Test). Primer was not used. Results are tabulated in Table 4.

Table 4

*ASTM D1735-21 (Standard Practice for Testing Water Resistance of Coatings Using Water Fog Apparatus).

[0060] The test compositions were also tested for corrosion resistance by applying on carbon steel metal panels with dimensions of 10 cm x 30 cm. The edges of each carbon steel panel were protected with insulating tape and the reverse protected with mica. The panels were exposed to continuous salt spray conditions (temperature 35° C) following the method of ASTM B 117-19 (Standard Practice for Operating Salt Spray (Fog) Apparatus). The instrument used was a Q-Fog, model CCT 1100 (available from Q-Lab). Film defects are shown in Table 5. Table 5

* According to ASTM D 714-02(2017)

** According to ASTM D 1654-08(2016)

[0061] The ASTM D 714-02(2017) standard employs photographic reference standards to evaluate the degree of blistering that may develop when paint systems are subjected to conditions which can cause blistering. The test method provides a standard procedure of describing the size and density of the blisters, according to photographic reference standards, so that comparisons of severity can be made. The photographic reference standards illustrate two characteristics of blistering: size and frequency. With respect to size, rate 10 has no blister, rate 8 represents the smallest size blister visible to the naked eye, and rate numbers 6, 4, and 2 represent progressively larger blister sizes. With respect to frequency, the photographic reference standards designate gradations (in order of most blisters to fewest) of Dense, Medium dense, Medium, and Few.

[0062] In ASTM D 1654-08 (2016), the rating is from 10 to 0. A rating of 10 means 0 mm; 9 means over 0 to 0.5 mm; 8 means over 0.5 to 1.0 mm; 7 means over 1.0 to 2.0 mm; 6 means over 2.0 to 3.0 mm; 5 means over 3.0 to 5.0 mm; 4 means over 5.0 to 7.0 mm; 3 means over 7.0 to 10.0 mm; 2 means over 10.0 to 13.0 mm; 1 means over 13.0 to 16.0 mm; and 0 means over 16.0 mm.

Example 2: Coating Compositions with Reduced Particle Sizes

[0063] An additional set of test emulsions (1B-6B) were prepared with the components shown in Table 6. The average particle sizes (Dp), based on volume, as measured using DLS, are also shown. Relative to the test compositions of Example 1, the test compositions of this Example generally had reduced average particle sizes. Coalescent (2,2,4-trimethyl-l,3-pentanediol monoisobutyrate) was added to the emulsions at 2% based on total weight of the emulsion composition.

Table 6

[0064] The test emulsions were then formulated into test coating compositions 1B-6B. Table 7 shows components of the resulting coating compositions.

Table 7

*Percent wt. based on total weight of the coating composition.

**Percent wt. based on total nonvolatile weight of the coating composition; coalescent was 2, 2, 4-trimethyl- 1,3 -pentanediol monoisobutyrate.

[0065] The “other components” included additional water, pigment, defoamer, biocide, rust inhibitor, rheology modifier, dispersant, and pH regulator components customary in the art.

[0066] The test compositions were subjected to stability testing according to ASTM D1849-95(2019) (Standard Test Method for Package Stability of Paint) at 50° C for 15 days. The test compositions (other than test composition 3B) had stability results that were acceptable, but not as effective as the test compositions of Example 3 (below).

Example 3: Coating Compositions with Increased Particle Sizes

[0067] An additional set of test emulsions (1C-8C) were prepared with the components shown in Table 8. The average particle sizes (Dp), based on volume, as measured using DLS, are also shown. Relative to the test compositions of Example 2, the test compositions of this Example generally had higher average particle sizes. Coalescent (2,2,4-trimethyl-l,3-pentanediol monoisobutyrate) was added to the emulsions at 2% based on total weight of the emulsion composition. Table 8

[0068] The emulsions were then formulated into coating compositions 1C-8C. Table 9 shows components of the resulting coating compositions. Values given represent weight percentages based on the total coating composition, with amounts of coalescent provided based on total nonvolatile weight of the emulsion composition.

Table 9

* Percent wt. based on total weight of the coating composition.

**Percent wt. based on total nonvolatile weight of the emulsion composition; coalescent was 2,2,4-trimethyl- 1,3-pentanediol monoisobutyrate.

[0069] The “other components” included additional water, pigment, defoamer, biocide, rust inhibitor, rheology modifier, dispersant, and pH regulator components customary in the art. [0070] The test compositions were subjected to stability testing according to ASTM D1849-95(2019) (Standard Test Method for Package Stability of Paint) at 50° C for 15 days and 23 days. Results are shown in Table 10.

Table 10

* Percent wt. based on total nonvolatile weight of the coating composition

[0071] The test compositions were applied on glass and appearance was evaluated according to ASTM D523-14 (2018) (Standard Test Method for Specular Gloss). Results are shown in Table 11. The most-often reported gloss value is at 60°.

Table 11

* Preferred gloss A is 15 or lower.

* * Preferred yellowing A is 2 or lower.

[0072] As shown, test compositions 1C and 2C, in particular, maintained gloss ratings and minimized yellowing.

[0073] Test compositions 1C and 2C were also applied to various substrates and their adhesion to these substrates was evaluated following ASTM D3359-22 (Standard Test Methods for Rating Adhesion by Tape Test). Primer was not used. Results are shown in Table 12.

Table 12

[0074] Test compositions 1C and 2C were also subjected to corrosion resistance testing under the same protocols of Example 1. Results are shown in Table 13.

Table 13

* According to ASTM D 714

** According to ASTM D 1654

Example 4: Coating Composition Combining First and Second Emulsions

[0075] Test composition 1C of Example 3 was modified to include an additional emulsion in addition to the emulsion 1C of Table 8. The additional emulsion was a styrene acrylic resin emulsion sold under the trade name MAINCOTE™ HG-100 Emulsion (available from Dow Chemical Company, Midland, MI). Test emulsion 1C was included at 16.8% by total weight of the coating composition and the styrene acrylic emulsion was included at 37.7% by total weight of the coating composition, with water and other customary components making up the remainder.

[0076] The modified test composition was applied on glass and appearance was evaluated according to ASTM D523-14 (2018) (Standard Test Method for Specular Gloss). Results are shown in Table 14. The most-often reported gloss value is at 60°.

Table 14

[0077] The modified test composition was also applied to various substrates and adhesion to these substrates was evaluated following ASTM D3359-22 (Standard Test Methods for Rating Adhesion by Tape Test). Primer was not used. Results are shown in Table 15. Table 15

[0078] The modified test composition was also subjected to corrosion resistance testing under the same protocols described in Examples 1 and 3. Results are shown in Table 16.

Table 16

* According to ASTM D 714-02(2017)

** According to ASTM D 1654-08(2016)

Example 5: Comparative Examples with Reduced (Meth)acrylamide

[0079] Additional coating compositions were formulated to evaluate adhesion performance with lower amounts of (meth) acrylamide monomer.

Table 17

[0080] The emulsions were then formulated into coating compositions ID and 2D. Table 18 shows components of the resulting coating compositions. Values given represent weight percentages based on the total coating composition, with amounts of coalescent provided based on total nonvolatile weight of the emulsion composition.

Table 18

Table 19

* Preferred gloss A is 15 or lower.

** Preferred yellowing A is 2 or lower.

[0081] Test compositions ID and 2D were also applied to various substrates and their adhesion to these substrates was evaluated following ASTM D3359-22 (Standard Test Methods for Rating Adhesion by Tape Test). Primer was not used. Results are shown in Table 20.

Table 20

[0082] Test compositions ID and 2D showed poor adhesion performance on various substrates relative to other test compositions.

[0083] Test compositions ID and 2D were also subjected to corrosion resistance testing under the same protocols described in Examples 1 and 3. Results are shown in Table 21.

Table 21

* According to ASTM D 714-02(2017)

** According to ASTM D 1654-08(2016)

Claims

CLAIMS We claim:

1. A coating composition, comprising:

(A) a first emulsion comprising a polymer formed from components comprising

(i) monomers comprising

(a) a (meth)acrylate, such as an alkyl (meth) acrylate, such as an alkyl methacrylate, such as methyl methacrylate, and/or a dialkyl acrylate, such as 2-ethylhexyl acrylate,

(b) an aromatic monomer having an ethylenically unsaturated group, such as styrene, and

(c) a (meth) acrylamide monomer, such as a ketone (meth)acrylamide, such as diacetone acrylamide, and

(ii) optionally, a first coalescent, such as an ester of a glycol, such as a monoester of a glycol, and/or an ether of a glycol,

(B) optionally, a second emulsion different from the first emulsion, and

(C) optionally, a crosslinking agent reactive with the (meth) acrylamide monomer.

2. The coating composition of claim 1, wherein the crosslinking agent comprises a dihydrazide, such as adipic dihydrazide, and/or wherein the crosslinking agent comprises a polyamine.

3. The coating composition of any preceding claim, wherein the first emulsion further comprises a dicarboxylic acid, such as itaconic acid.

4. The coating composition of claim 3, wherein the dicarboxylic acid is included at a concentration of 0.25% to 2%, such as 0.5% to 1.5%, by total weight of monomers of the first emulsion.

5. The coating composition of any preceding claim, wherein the polymer of the first emulsion has a volume average particle size of 110 nm to 150 nm, such as 120 nm to 140 nm or 125 nm to 135 nm, as measured using dynamic light scattering (DLS).

6. The coating composition of any preceding claim, wherein the composition is free or essentially free of alkylphenol ethoxylates (APEOs).

7. The coating composition of any preceding claim, wherein monomers make up 15% to 65% of the total weight of the first emulsion.

8. The coating composition of any preceding claim, wherein the first emulsion comprises: an alkyl methacrylate, such as methyl methacrylate, at a concentration of 25% to 45%, such as 30% to 40%, based on total weight of monomers of the first emulsion; a dialkyl acrylate, such as 2-ethylhexyl acrylate, at a concentration of 15% to 45%, such as 30% to 40%, based on total weight of monomers of the first emulsion; the aromatic monomer having an ethylenically unsaturated group at a concentration of 20% to 30% based on total weight of monomers of the first emulsion; and/or the (meth) acrylamide monomer at a concentration of 0.5% to 3%, such as 0.75% to 2%, or 1% to 1.5%, based on total weight of monomers of the first emulsion.

9. The coating composition of any preceding claim, wherein: the first emulsion omits the first coalescent and has a glass transition temperature (Tg) of 20° C to 35° C, such as 25° C to 30° C, as measured by differential scanning calorimetry (DSC); or the first emulsion includes the first coalescent and has a Tg of 0° C to 10° C, such as 2° C to 8° C, as measured by DSC.

10. The coating composition of any preceding claim, the coating composition further comprising a second coalescent, such as an ester of a glycol, such as a monoester of a glycol, and/or an ether of a glycol, wherein the second coalescent is separate from the first emulsion.

11. The coating composition of claim 10, wherein the first coalescent and the second coalescent are the same.

12. The coating composition of claim 10, wherein the first coalescent and the second coalescent are different.

13. The coating composition of any of claims 10-12, wherein: the first coalescent is included at 1% to 15%, such as 1% to 12%, or 1% to 10%, or 1% to 9%, by total weight of the coating composition; and/or the second coalescent is included at 1% to 15%, such as 1% to 12%, or 1% to 10%, or 1% to 9%, by total weight of the coating composition; and/or the second coalescent makes up 20% to 90%, such as 35% to 85%, or 30% to 80%, or 35% to 80%, of the total amount, by weight, of total coalescent in the coating composition.

14. The coating composition of any preceding claim, wherein the first coalescent compound comprises: a monoester of (i) a glycol and (ii) a butyric acid or an isobutyric acid, such as 2,2,4-trimethyl-l ,3 -pentanediol monoisobutyrate; an ethylene glycol ether, such as diethylene glycol monobutyl ether; and/or a propylene glycol ether, such as dipropylene glycol mono n-butyl ether.

15. The coating composition of any preceding claim, wherein (B) the second emulsion different from the first emulsion comprises a polymer formed from components comprising (meth)acrylate monomers, such as styrene (meth)acrylic monomers.

16. The coating composition of any preceding claim, wherein the coating composition, when cured, exhibits: a change in gloss (60°) after 23 days of no more than 15, such as no more than 12.5, or no more than 10, or no more than 7.5, according to ASTM D523-14(2018); and/or a change in yellowing index after 23 days of no more than 2, such as no more than 1.8, according to ASTM D523-14(2018).

17. The coating composition of any preceding claim, wherein the coating composition, when applied to at least a portion of a substrate and cured, exhibits an adhesion rating of 3B or greater, according to ASTM D3359, wherein the substrate comprises aluminum, carbon steel, galvanized steel, and/or ceramic tile.

18. The coating composition of any preceding claim, wherein the coating composition, when cured, exhibits: no more than “Few” blisters at no lower than rate 4, according to ASTM D 714-02(2017), after 96 hours continuous salt spray exposure according to ASTM B 117-19; and/or a mean creepage from scribe rating of 5 or higher, according to ASTM D 1654- 08(2016), after 96 hours continuous salt spray exposure according to ASTM B 117-

19.

19. A method for coating a substrate, comprising: applying the coating composition of any preceding claim to at least a portion of a substrate.

20. The method of claim 19, wherein the substrate comprises: metal, such as carbon steel, aluminum, or galvanized steel; ceramic; a masonry surface, such as brick, stone, or concrete; drywall; and/or wood.

21. A substrate coated with any one of the coating compositions of claims 1-18.