Antifouling building composition

Abstract

Disclosed herein is an aqueous building composition that forms a paint film on a substrate that is resistant to hydrophobic and hydrophilic stains. The building composition includes a film-forming latex resin, a high molecular weight silicone resin, and wax microspheres. The anti-fouling building composition may also include at least one organic bulking pigment, a fluorine-containing surfactant, and a phosphate monomer.

Description

TECHNICAL FIELD

[0001] The present invention relates to paint films formed from aqueous architectural compositions, including paints and deck stains, that have stain resistance, i.e., resistance to discoloration caused by both hydrophobic and hydrophilic stains, and are easy to clean. BACKGROUND

[0003] Commercial water-borne or water-borne emulsion paints and deck stains are not resistant to all common stains. When a stain contacts a paint film, a noticeable mark is left on the paint film that requires cleaning by various cleaning methods to restore the visual appearance of the paint film. Such commercial paints are considered cleanable, but not necessarily stain resistant. Certain commercial paints lack durability and degrade when cleaned with chemical cleaners, and some have low scrub resistance and poor gloss / light gloss retention.

[0004] Generally, paint films formed from architectural compositions can resist either hydrophilic stains or hydrophobic stains, depending on the hydrophobicity / hydrophilicity of the polymeric latex resin in the architectural composition, but generally cannot resist both types of stains. Architectural compositions used herein include at least paints and deck stains.

[0005] The use of latex resin particles having small particle size, e.g., less than 130 nm, results in a tighter film, e.g., smaller gaps between the latex particles, which can minimize the penetration of stains into the paint film.

[0006] Various approaches to stain resistant architectural compositions have been proposed in the patent literature. U.S. Patent No. 8,158,713 discloses a stain resistant coating composition having thermoplastic latex particles copolymerized from predominantly mono-olefinically unsaturated monomers, and phosphorous-containing monomers, ethyl acrylate or methyl acrylate monomers, and beta-dicarbonyl or cyano-carbonyl monomers. U.S. Patent No. 8,318,848 discloses a coating composition having a copolymer made from predominantly mono-olefinically unsaturated monomers, a small amount of carboxylic acid, and a small amount of phosphorous-containing monomers, and a non-ionic surfactant. U.S. Patent No. 8,158,714 discloses a method of mixing an opacifying pigment with a thickening agent at a certain shear rate, and mixing it with a latex binder copolymer of acrylic acid and phosphorous-containing monomers.

[0007] US 10,005,921 discloses an anti-stain paint composition wherein the polymer comprises 3-70% of vinyl acetate, 2-65% of styrene, 20-55% of (meth)acrylate, 0.1-6% of wax and 14-55% of pigment. US 10,005,921 discloses an anti-stain paint composition wherein the polymer comprises 25-90% of vinyl acetate, 5-75% of ethylene ester of neodecanoic acid and / or ethylene ester of 2-ethylhexanoic acid, 0.1-6% of wax and 14-55% of pigment.

[0008] US 10,800,927 teaches an anti-stain composition for improved stain removal but not necessarily stain resistance comprising an emulsion copolymer of a monomer mixture comprising monomers having the formula:

[0009]

[0010] wherein R1 is H or methyl, X is a divalent organic alkylene oxide group, and R2 is H or an aliphatic or aromatic hydrocarbon group.

[0011] CN 103849267 discloses an anti-stain composition containing an acrylic resin film former, a PE wax and a fluorosurfactant, which is known to provide some stain resistance.

[0012] US Patent No. 11,059,980 discloses an anti-stain composition comprising (i) an ethylenically unsaturated nonionic monomer, (ii) a first acid monomer and (iii) a second acid monomer. The ratio of the first acid monomer to the second acid monomer is greater than 0.7. An example of the first acid monomer is a phosphate-based monomer and an example of the second acid monomer is methacrylic acid (MAA). This patent requires three different film forming monomers and MAA as the second acid. The anti-stain property disclosed in US Patent 11,059,980 refers to stains having a combination of hydrophobic and hydrophilic stains to a high residual visible stain, i.e. a delta E of less than 80.

[0013] US Published Patent Application No. 2020 / 0354603 discloses a composition having some stain resistance. The composition comprises (i) a polymer system, a coalescing aid and a pigment. The polymer system comprises a latex polymer and an alkali-soluble resin (ASR) “blended” together. The ASR has a molecular weight of 1,500 to 20,000; and an acid value of 100 to 250, and comprises 2.5-15% by weight of all polymers.

[0014] The above patents and patent applications represent different approaches to anti-stain paint formulations but do not address the problem of resistance to both hydrophilic and hydrophobic stains.

[0015] Accordingly, there remains a need for stain resistant architectural compositions that are capable of resisting both hydrophobic and hydrophilic stains. SUMMARY

[0016] Accordingly, one embodiment of the present application is directed to an aqueous architectural composition that forms a paint film on a substrate that is capable of resisting both hydrophobic and hydrophilic stains comprising a film-forming latex resin for forming the paint film, optionally an opacifying pigment, a silicone resin, wax microspheres, and at least one organic extender pigment. The silicone resin has a weight molecular weight of greater than about 10,000 Daltons, preferably greater than about 15,000 Daltons, preferably greater than about 20,000 Daltons, preferably greater than about 25,000 Daltons, preferably greater than about 30,000 Daltons, and less than about 100,000 Daltons. The PE wax microspheres have an average diameter (D 50 ) in the range of about 6 microns to 18 microns, and comprise about 3 wt% to about 9 wt%, preferably about 3.5 wt% to about 8.5 wt%, preferably about 4. wt% to about 7.5 wt% of the aqueous architectural composition. The silicone resin comprises about 1 wt% to about 4 wt%, preferably about 1.25 wt% to about 3.5 wt%, preferably about 1.5 wt% to about 3 wt% of the aqueous architectural composition. Preferably, all of the extender pigments are organic.

[0017] Preferably, the film-forming latex resin comprises phosphate monomers, and the phosphate monomers comprise 0.1 wt% to 1 wt%, preferably 0.5-0.9 wt%, more preferably 0.6-0.8 wt% of all monomers of the latex resin.

[0018] Preferably, the film-forming latex resin is substantially free of wax- seeded latex, preferably free of wax-seeded latex.

[0019] Preferably, the film-forming latex resin comprises primarily (meth)acrylate monomers or vinyl and (meth)acrylate monomers.

[0020] Preferably, the film-forming copolymer has a total Tg in the range of 0°C to 50°C (calculated by the Flory Fox equation), and preferably 0°C to 30°C, or 2.5°C to 27.5°C, or 5°C to 25°C.

[0021] Preferably, the aqueous architectural composition 1 further comprises a fluorosurfactant, and the fluorosurfactant comprises less than 1 wt%, preferably 0.1 wt% to 0.3 wt%, preferably 0.15 wt% to about 0.25 wt% of the aqueous architectural composition.

[0022] Preferably, the aqueous architectural composition can comprise a Gemini surfactant, a polyether-siloxane surfactant, or a neutralized alcohol phosphate ester type surfactant in an amount of 0.25 wt% to 0.75 wt%, preferably 0.35 wt% to 0.65 wt% of the paint composition.

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The present invention relates to architectural compositions comprising components selected to resist both hydrophobic and hydrophilic stains. The architectural compositions of the present invention form paint films that resist both types of stains as well as marring. Preferably, these paint films can also be cleaned using common household mild cleaning products. Stain resistance differs from cleanability in that it is the ability to resist stains from remaining on the paint film after the stain has been removed or wiped off the paint film without cleaning. Stain resistance and cleanability tests are described below, respectively.

[0025] Similar to conventional architectural compositions that include various commercial lines, topcoats, and tintable basecoats, the architectural compositions of the present invention comprise one or more water-borne or water-based latex resins mixed with opacifying pigments such as titanium dioxide used in certain tintable basecoats, and common additives including, but not limited to, dispersants / rheology modifiers, surfactants, defoamers, inorganic extending pigments, coalescing aids, biocides, and the like. The architectural compositions of the present invention comprise selected components that replace one or more of the additives or are in addition to the common additives.

[0026] One selected component of the architectural compositions of the present invention is an organosilicon resin having a weight average molecular weight (Mw) of greater than about 10,000 Daltons or greater than about 15,000 Daltons, preferably greater than about 20,000 Daltons or greater than about 25,000 Daltons, and more preferably greater than about 30,000 Daltons, and less than about 100,000 Daltons. The organosilicon resin is added in an amount of about 1 wt% to about 4 wt%, preferably about 1.25 wt% to about 3.5 wt%, and more preferably about 1.5 wt% to about 3 wt%. While organosilicon resins generally have film-forming properties, within the preferred percentage ranges, the organosilicon does not film-form independently, but is used in addition to the primary film-forming resin. The organosilicon resin imparts hydrophobicity, slip, and scratch resistance to the paint film.

[0027] As used herein, weight percent when used in reference to polymerization of a copolymer refers to the weight percent of the solid monomers, i.e., without regard to water or other liquids. When used in the let down stage or mixing of the copolymer, opacifying pigment, extending pigment, and additives to produce the architectural composition, weight percent refers to the weight percent of the entire paint composition including water and other liquids. The weight of the resin listed in the paint / colorant formulation includes the water and / or solvent suspending the copolymer.

[0028] Suitable silicone resins are available from Worlee-Chemie as WorleeSol SE 420W, Dow Corning DOWSIL Q7- 4200, and from Momentive Performance Materials, Inc. as Q7- 4200. TM 210S, from Momentive Performance Materials, Inc. DRI aqueous silicone from Wacker Chemie AG Hydropalat SL 3682 from BASF, and Siltech C-4405 from Siltech Corporation were obtained.

[0029] Another selected component is a wax microsphere or wax particle having an average diameter D 50 of about 6 microns to about 18 microns. Wax particles having different average diameters can be used together. One preferred wax particle is a polyethylene (PE) wax particle, and is added to the architectural composition in about 3.0 wt% to about 9 wt%, preferably about 3.5 wt% to about 8.5 wt%, and more preferably about 4 wt% to about 7.5 wt%.

[0030] Micronized wax microspheres or powders are commercially available from Honeywell as ACumist micronized oxidized polyethylene powders having a volume average particle size (mV) of about 6 to about 7.5 pm (D 50 6 microns), about 10 to about 13 pm (D 50 12 microns), about 16 to about 19 pm (D 50 18 microns), designated as ACumist A-6, A-12, and A-18, respectively. Combinations of these particle sizes can be used in the same paint or colorant composition. Other suitable, commercially available oxidized HDPE wax powders include, but are not limited to, Petrolite C and Petrolite E class wax powders from Baker-Petrolite Corporation, and Deurex EO from Deurex AG.

[0031] The optional fluorosurfactant is used in sufficient amount to minimize or prevent the creation of divots or dimples on the paint film surface. The fluorosurfactant is added in an amount of about 0.1 wt% to about 0.3 wt%, preferably about 0.15 wt% to about 0.25 wt%. A small amount of surfactant other than fluorosurfactant can be added in less than about 1 wt%.

[0032] Fluorosurfactants generally comprise a polar hydrophilic head and a highly hydrophobic fluorocarbon tail. Fluorosurfactants are described in N. M. Kovalchuk et al., "Fluoro- vs Hydrocarbon Surfactants: Why Do They Differ in Wetting Performances?" in Advances in Colloid and Interface Science, 210 (2014) 65-71, which is incorporated by reference in its entirety. Fluorosurfactants significantly reduce the surface tension and surface energy of paint compositions, as well as the surface energy of paint films formed from these paint compositions. Fluorosurfactants can significantly reduce surface tension and surface energy compared to conventional hydrocarbon surfactants. Suitable fluorosurfactants include Zonyl® FS-## family of fluorosurfactants, commercially available from Chemours FS-## family of fluorosurfactants, commercially available from AGC Seimi Chemical Co., Ltd. fluorosurfactants, and FC-## fluorosurfactants from 3M.

[0033] Other surfactants can be used in place of, or in addition to, fluorosurfactants. These other surfactants include, but are not limited to, Gemini surfactants, polyether-silicone surfactants, neutralized alcohol phosphate type surfactants, and can be preferred for addition at 0.25 to 0.75 wt.%, preferably 0.35 to 0.65 wt.% of the paint composition when fluorosurfactants are not used. Suitable other surfactants are commercially available as Stepcote W-877, Tego Twin 4100, Additol XW 6580, and the Dynol series. In order for the architectural composition to wet the substrate to be covered, and for no defects (such as pitting or dented paint films) to appear on the paint film, the surface tension of the paint should be lower than the surface tension of the architectural composition, and fluorosurfactants are effective at reducing the surface tension of the architectural composition. Gemini surfactants, polyether-silicone surfactants, and neutralized alcohol phosphate type surfactants can be used as a replacement for fluorosurfactants to reduce the surface tension of the architectural composition in higher amounts.

[0034] Another selected component is an organic additive pigment, rather than an inorganic additive pigment. Additive pigments are used to alter the pigment-to-resin (PVC) ratio or to adjust the smoothness or gloss of the paint composition. Additive pigments are discussed in commonly owned U.S. Patent Publication No. 11,518,893, which is incorporated herein by reference in its entirety. Typically, inorganic additive pigments are added to paints, such as diatomaceous earth (amorphous silica), silica, ground and precipitated calcium carbonate, ground and calcined aluminum silicate, magnesium silicate (talc), potassium aluminum silicate (mica), nepheline syenite, etc. The co-inventors of this invention have found that inorganic pigments are generally more hydrophilic and easier to color. Furthermore, inorganic additive pigments promote higher porosity on the film surface, which attracts and retains more stains. In a preferred embodiment, inorganic additive pigments are not used. In an alternative embodiment, certain inorganic pigments may be included, for example, harder pigments or pigments with a more rounded shape, which may be substantially encapsulated within or encapsulated by the paint film.

[0035] Suitable organic additive pigments (that do not form films) include, but are not limited to, opaque acrylic copolymers (Ropaque). TM Ultra or Ultra EF), styrene acrylic resin (Joncryl) TM ), polyurethane (PU) microspheres. Suitable organic additive pigments may also include polybutyl acrylate microspheres and silicone microspheres.

[0036] Joncryl styrene acrylic resin pigment (Joncryl) TM It is a low molecular weight, high acid value polymer particle having a molecular weight of about 1,000 to about 20,000, preferably about 5,000 to about 17,000 and more preferably about 8,000 to about 17,000 and an acid value of about 150 to about 250, preferably about 200 to about 250, and is soluble in alkaline solutions.

[0037] PU microspheres, which can be used as additive pigments, are solid particles and possess elasticity. Such solid particles resist breakage due to their elasticity. PU microspheres or particles are available from SuperColori, Italy. www.supercolori.com As and Commercially available, and can be dispersed in water or supplied as dried beads. PU microspheres are also available from KOBO, New Jersey, and as Art Pearls from Negami Chemical Industrial Co., Ltd., Japan. TM "C" series PU microspheres.

[0038] The above selected components are combined or sub-combinations thereof with film-forming resin and opacifying pigment to form the architectural composition of the present application as shown in the following examples. One or more of the selected components can be omitted from the architectural composition of the present application. As used herein, the selected components are non-film forming and are added directly to the architectural composition (e.g., paints and deck stains) unless otherwise indicated.

[0039] The opacifying pigment preferably includes titanium oxide, which is widely available, including Tronox 826or 813and Ti-Pure R-706, among others. Another opacifying pigment is zinc oxide. Certain 4- base tinted paints do not contain an opacifying pigment.

[0040] The film-forming resin is made by homo- or co-polymerization (e.g., by emulsion polymerization) of all acrylic copolymers or vinyl-acrylic copolymers. Styrene and other unsaturated olefinic monomers can be co-polymerized.

[0041] The film-forming resin suitable for use in the present application is co-polymerized from the monomers discussed herein unless otherwise indicated in the example formulations below. The film-forming resin in the present application does not rely on the wax seeded emulsion disclosed in commonly owned U.S. Patent Nos. 8,980,995 and 11,230,645 and U.S. Patent Application Publication No. US2021 / 0230442. The inventors of the present application sought to solve a different problem in the art, namely resistance to hydrophobic and hydrophilic stains, which is different from the earlier commonly owned patents and patent applications. The film-forming resin in the present application also does not rely on the combination of three resins (wax seeded emulsion, hard emulsion with Tg > 30°C, and elastomeric resin) to resist cracking of the dry paint film as described in the '442 patent publication. The present application also does not rely in certain embodiments on the combination of wax seeded emulsion resin, wax particles of a certain particle size, and coalescing aids to resist abrasion of the dry paint film as described in the '645 patent.

[0042] It is preferred in the present application to omit the wax seeded emulsion. In other words, the film-forming resin used in the present application is preferably free or substantially free of wax seeded emulsion. As used herein, "substantially free" means less than about 5 wt.%, preferably less than about 2.5 wt.%, and more preferably less than about 1.0 wt.% of the total monomer weight.

[0043] Suitable emulsion particles include, but are not limited to, acrylic, vinyl, vinyl-acrylic, or styrene-acrylic polymers or copolymers. The emulsion particles coalesce and / or crosslink to form a paint film on a substrate. As shown in the examples below, the present application preferably uses emulsions made substantially from acrylic monomers. Exemplary, non-limiting monomers suitable for forming the emulsion particles of the present application are described below.

[0044] Any (meth)acrylic monomer can be used in the present application. Suitable (meth)acrylic monomers include, but are not limited to, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, 2-ethylhexyl (meth)acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylamide, alkyl (meth)acrylic acids such as methyl (meth)acrylic acid, (meth)acrylic acid, wet adhesion monomers such as N-(2-methacryloyloxyethyl)ethylenurea, and multifunctional monomers such as divinylbenzene, diacrylates, for crosslinking functionality, etc., acrylic acid, ionic acrylic acid salts, alkyl acrylic acids, ionic alkyl acrylic acid salts, halogenated acrylic acids, ionic halogenated acrylic acid salts, acrylamide, alkyl acrylamides, monoalkyl acrylamides, monoalkyl alkyl acrylamides, alkyl acrylates, alkyl alkyl acrylates, acrylonitrile, alkyl acrylonitriles, dialkyl acrylamides, dialkyl alkyl acrylamides, hydroxyalkyl acrylates, alkyl hydroxyalkyl acrylates, acrylates of only partially esterified alkylene glycols, acrylates of only partially esterified non-polymeric polyhydroxy compounds such as glycerol, acrylates of only partially esterified polymeric polyhydroxy compounds, itaconic acid, itaconic acid monoesters and diesters, and combinations thereof. Preferred (meth)acrylic alkyl ester monomers are methyl methacrylate and butyl acrylate.

[0045] Preferred monomers containing aromatic groups are styrene and a-methylstyrene. Other suitable monomers containing aromatic groups include, but are not limited to, 2,4-diphenyl-4-methyl-1-pentene, 2,4-dimethylstyrene, 2,4,6-trimethylstyrene, 2,3,4,5,6-pentafluorostyrene, (vinylbenzyl)trimethylammonium chloride, 2,6-dichlorostyrene, 2-fluorostyrene, 2-isopropenylaniline, 3(trifluoromethyl)styrene, 3-fluorostyrene, a-methylstyrene, 3-vinylbenzoic acid, 4-vinylbenzyl chloride, a-bromostyrene, 9-vinylanthracene, and combinations thereof.

[0046] Preferred monomers containing primary amide groups are (meth)acrylamides. Suitable monomers containing amide groups include, but are not limited to, N-vinyl formamide or any vinyl amide, N,N-dimethyl(meth)acrylamide, N-(l,l-dimethyl-3-oxobutyl)(meth)acrylamide, N-(hydroxymethyl)(meth)acrylamide, N-(3-methoxypropyl)(meth)acrylamide, N-(butoxymethyl)(meth)acrylamide, N-(isobutoxymethyl)acryl(meth)acrylamide, N-[tris(hydroxymethyl)methyl]acryl(meth)acrylamide, 7-[4-(trifluoromethyl)coumarin](meth)acrylamide, 3-(3-fluorophenyl)-2- propenamide, 3-(4-methylphenyl)(meth)acrylamide, N-(tert-butyl)(meth)acrylamide, and combinations thereof. These monomers can be polymerized with the acrylic monomers listed above. The general formula for a vinyl (meth)amide is:

[0047]

[0048] and the general formula for a (meth)acrylamide is:

[0049]

[0050] wherein R1and R2may be -H, -CH3, -CH2CH3, and other substituted organic functional groups, and R3may be -H, an alkyl group, or an aryl group.

[0051] In one embodiment, styrene monomers, such as styrene, methylstyrene, chlorostyrene, methoxystyrene, and the like, are preferably copolymerized with the (meth)acrylamide monomers.

[0052] In one embodiment, the aqueous latex polymer can further comprise a vinyl monomer. Suitable monomers of this type for use in the present application include any compound having a vinyl functional group (i.e., a -CH=CH2group). Preferably, the vinyl monomer is selected from the group consisting of vinyl esters, vinyl aromatics, vinyl aliphatics, vinyl alkyl ethers, and mixtures thereof.

[0053] Suitable vinyl monomers include vinyl esters such as, for example, vinyl acetate, vinyl propionate, vinyl laurate, vinyl pivalate, vinyl nonanoate, vinyl decanoate, vinyl neodecanoate, vinyl butyrate, vinyl hexanoate, vinyl benzoate, vinyl isopropyl acetate, and similar vinyl esters; nitrile monomers such as (meth)acrylonitrile and the like; vinyl aromatic hydrocarbons such as, for example, styrene, methylstyrene and similar lower alkyl styrenes, chlorostyrene, vinyl toluene, vinyl naphthalene, and divinyl benzene; vinyl aliphatic hydrocarbon monomers such as, for example, vinyl chloride and vinylidene chloride, and alpha olefins such as, for example, ethylene, propylene, isobutylene, and conjugated dienes such as 1,3-butadiene, methyl-2-butadiene, 1,3-pentadiene, 2,3-dimethyl butadiene, isoprene, cyclohexene, cyclopentadiene, and dicyclopentadiene; and vinyl alkyl ethers such as, for example, methyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, and isobutyl vinyl ether.

[0054] Commonly used monomers and their glass transition temperatures (Tg) and solubility in water are shown below. Since the hydrophobicity and hydrophilicity of monomers are rarely discussed quantitatively in scientific literature, the inventors of the present invention utilized their solubility in water as a proxy variable.

[0055] Monomers Solubility in water at T° Tg (°C) BA 2 g / l at 23°C -54 2-EHA 0.0096 g / l at 25°C -50 EA 15-20 g / l at 25°C -24 MMA 15 g / l at 30°C 105 MA 10-50 g / l at 22°C 10 MAA 89 g / l at 20°C 228 Styrene 0.3 g / l at 25°C 100 VA 20 g / l at 25°C 30 iOMP <0.00767 g / l at 20°C n / a DMA 1 μg / l at 25°C -65

[0056] 2-EHA is known to be hydrophobic and has very low solubility; MMA has a relatively high solubility, while BA has a solubility between 2-EHA and MMA.

[0057] The overall Tg of the film-forming copolymer ranges from 0°C to 50°C, and preferably from 0°C to 30°C or from 2.5°C to 27.5°C or from 5°C to 25°C, according to the Flory Fox equation.

[0058] Other exemplary suitable polymeric resin copolymers include those polymerized with a small amount of phosphate monomer, such as Resins 1 and 2 shown in Table 1 below.

[0059] Table 1

[0060]

[0061]

[0062]

[0063] § 1,2-benzisothiazolin-3-one (BIT), N-(butyl)-1,2-benzisothiazolin-3-one (BBIT), 5-chloro-2-methyl-4-isothiazolin-3-one (CIT or CIMIT), and / or 2-methyl-4-isothiazolin-3-one (MIT).

[0064] The latex particles can have a crosslinking monomer added to the monomer mixture or first portion of the monomer mixture used for an internal stage, such as a core or two internal cores / stages. Crosslinking can increase the toughness of the dry paint film, for example, increasing its scrub resistance or having improved scrub-ability. Preferred crosslinking monomers include, but are not limited to, acetoacetoxyethyl methacrylate (AAEM) and diacetone acrylamide (“DAAM”). AAEM and / or DAAM crosslinking monomers can be copolymerized to 10 wt% of the total monomers, preferably 1 wt% to 8 wt%, more preferably 2 wt% to 6 wt%, and more preferably 3.5 wt% to 4.5 wt%.

[0065] Other suitable crosslinking monomers include, but are not limited to, diacetone methylacrylamide (DAMAM), allyl methyl acrylate (AMA), and / or 1,4-butanediol diacrylate, which are added to the pre-emulsion composition and can be copolymerized with the film-forming monomers to form the latex particles.

[0066] It has been reported that crosslinking of the polymer is provided by reacting the AAEM or DAAM moieties with a suitable crosslinking agent in the aqueous phase, including adipic acid dihydrazide (“ADH”). The ADH crosslinking agent by ketone hydrazide reaction has a considerable reaction rate in aqueous solution (“The Diacetone Acrylamide Cross-linking Reaction and its Influence on the Film Formation of an Acrylic Latex,” Journal of Coatings Technology and Research, 5(3), 285-297, 2008.). To minimize this premature crosslinking, the ADH hydrazine is essentially replaced by a hydrazone or blocked hydrazine particle, which is discussed in commonly owned U.S. Published Patent Application No. 2012 / 0142847 and commonly owned U.S. Patent No. 9,040,617, which are incorporated by reference in their entirety. The hydrazone crosslinking particle does not react with the AAEM or DAAM moieties during storage and converts to a hydrazine crosslinking particle when the aqueous component evaporates after application to a substrate.

[0067] Exemplary suitable polymeric resin compositions also include the vinyl acrylic copolymers contained in Resin 2 shown in Table 1.

[0068] The paint compositions are made at the paint shop stage, i.e., after the latex resin is polymerized or otherwise made, at which point the latex resin, opacifying pigment, and additives are mixed to make the paint. An exemplary paint composition (Paint 1) utilizing Resin 1 is shown in Table 2A below.

[0069] Table 2A

[0070]

[0071]

[0072] Additional topcoats of Paint 1 made with Resin 1 were also prepared, as shown in Table 2B.

[0073] Table 2B

[0074]

[0075]

[0076]

[0077] The architectural compositions of the present application were compared to commercial paints to determine their relative cleanability under the COR-MTD-119 standard, as well as their stain resistance under a newly developed test.

[0078] The stain removal test performed in these experiments corresponds to the Master Paint Institute (MPI) COR-MTD-119 standard. Higher values indicate that stains are more difficult to remove from the paint film. Lower values are more preferred. The numbers reported are the sum of the change in color readings (Delta E values in CIE 2000 units) of the pre-stained paint film and the post-stained and cleaned paint film, as measured by a spectrophotometer, after applying a variety of different stains to the paint film. The stains included hot regular coffee, red wine, ketchup, yellow mustard, and graphite. The cleaning solution contained 0.5% nonylphenoxyethanol, 0.25% trisodium phosphate (TSP), and 99.25% deionized water. The cleaning solution was applied using a 430 g sponge per rack for 500 cycles. The color change caused by each stain was summed and reported for each example.

[0079] In the COR-MTD-119 standard, all but the hydrophobic graphite stain are hydrophilic. TTP (a raw brown pigment containing iron oxide and manganese oxide, white petrolatum, and ExxonMobil's Isopar L synthetic isomeric hydrocarbon solvent) and Litter (lanolin, petrolatum, lamp black pigment, margarine, and mineral oil) are hydrophobic stains. TM L synthetic isomeric hydrocarbon solvent) and Litter (lanolin, petrolatum, lamp black pigment, margarine, and mineral oil) are hydrophobic stains.

[0080] A stain resistance test was developed by the co-inventors and used to demonstrate the stain resistance of the architectural compositions of the present invention. For this test, two coats of paint were applied over a base coat of primer on a sheet rock. The painted sheet rock was then cured for two days in the laboratory before the stains were applied. A 9 milliliter liquid stain was applied using an 8 mil gap cube applicator and solid stains were applied to the sheet rock which was laid flat on a table. Immediately after the stains were applied, the panel was lifted vertically for one minute. After one minute, a mild cleaning method was used to wipe the panel five times using a cleaning solution (Lysol for tough stains and a mild cleaner for easier stains) and then three times with a sponge using water. No pressure or only minimal pressure was applied when using the sponge.

[0081] The stain resistance of the paint film can be judged by a human test panel or observer by visual observation and assigned a score of 1 (low stain resistance, high stain observed) to 5 (no stain observed). The stains used were black and blue markers, crayons, pencils, ballpoint pens, lipstick, wine / juice. Alternatively, instead of using visual observation, a spectrophotometer can be used to measure the stain resistance in ΔΕ units. The area to be stained was set at 2 inches by 1 inch (5 cm by 2.5 cm), for example, by cutting this size area from a card stock; however, the stained area can be any size that can accommodate the spectrophotometer. A 9 milliliter liquid stain (wine / juice) was applied using an 8 mil gap cube and solid stains were colored on the sheet rock. The stain caused by the ballpoint pen was omitted from the measurement test because it was impractical to color a 2 inch by 1 inch stain area with a ballpoint pen.

[0082] The visual analysis of the stain resistance test can be used as a screening technique to determine if a spectrophotometer measurement analysis is applied. The visual analysis can also be used for comparison in one experiment or by the same test panel. The spectrophotometer measurement analysis can be used extensively in multiple experiments.

[0083] A summary of the cleanability test (COR-MTD-119) and the stain resistance test is shown below.

[0084]

[0085] Sheet rock or drywall was used in the stain resistance test to more accurately represent a wall. The reason the sheet rock was lightly cleaned was to remove solid stains such as markers, crayons and lipstick that had adhered to the sheet rock and liquid stains that needed to be rolled off and gently wiped clean before the stain resistance could be determined. The crayon, pencil marks and lipstick are hydrophobic and the other stains are hydrophilic.

[0086] Cleanability and stain resistance tests measure different properties of the paint film. The cleanability test measures the ability of the paint film to be cleaned after being soiled. The stain resistance test measures the ability of the paint film to resist stains.

[0087] The paint film made with Paint 1 / Resin 1 was compared to paint films made from a commercial scuff resistant eggshell paint and a commercial premium interior wall eggshell paint produced by Benjamin Moore, as well as a premium interior wall eggshell paint produced by another manufacturer. The ability of the paint films to be cleaned after being soiled is shown in Table 3 below. Paint 1 of the present invention had comparable or better cleanability than the commercial paints. The results in Table 3 show that the film formed by Paint 1 of the present invention can clean both hydrophobic and hydrophilic stains.

[0088] Table 3

[0089]

[0090] The 60° gloss values indicate that the paints in Table 3 have an eggshell finish (about 10-25 units). The 85° gloss values also indicate that these paints have an eggshell finish (10-35 units). Gloss / luster units are reported according to the Master Paint Institute (MPI) Gloss Value, reproduced below.

[0091] The results of the stain resistance test are shown in Table 4 below.

[0092] Table 4

[0093]

[0094]

[0095] Berry juice is another hydrophilic stain and was used in place of red wine.

[0096] The test results in Table 4 show that the architectural compositions of the present invention perform well against both types of stains. The visual stain resistance test shows that Paint 1 of the present invention can resist both hydrophobic and hydrophilic stains, while the commercial paints exhibit good stain resistance (4 or 5 points) for some stains, but poor stain resistance (1.0 or 1.5 points) for other stains. The measured stain resistance test confirms the visual stain resistance test results. The ΔE measurements for Paint 1 of the present invention are consistently low, indicating good stain resistance. On the other hand, the commercial paints exhibit significantly lower stain resistance. For both commercial paints, their resistance to stains caused by the hydrophilic black and blue markers is fairly low, i.e., ΔE measurements ranging from 28.03 to 78.42, while exhibiting good resistance to the hydrophobic crayon, pencil, and lipstick stains, with ΔE measurements ranging from 0.25 to 2.55.

[0097] The results in Table 4 demonstrate that the paints of the present application can resist both hydrophobic and hydrophilic stains.

[0098] Additional stain resistance tests were performed with the paints of the present application, which had lower gloss values, including matte gloss, than the comparative commercial paints, as shown in Table 5. The additional tests showed similar results to the test results shown in Table 4. The co-inventors note that, in general, it is much more difficult to impart stain resistance to paints with higher pigment content, such as matte gloss. Table 5 shows that good stain resistance for matte gloss can be achieved with paint 1 of the present application.

[0099] Table 5

[0100]

[0101] The inventors of the present application also developed additional embodiments or examples of the architectural compositions of the present application, namely paints 2 utilizing resin 2 described above, respectively. Another batch of paint 1 / resin 1 was also prepared for this experiment. The cleanability test results are shown in Table 6, and the stain resistance test results are shown in Table 7.

[0102] Table 6

[0103]

[0104]

[0105] Table 7

[0106]

[0107] The test results in Tables 6 and 7 show that resin 1 contains mostly (meth)acrylate monomers that are similar to each other and produce similar cleanability and stain resistance results. Resin 2 contains vinyl and meth(acrylate) monomers and is more hydrophilic than resin 1. Resin 2 also has a larger particle size (360 nm) than resin 1 (119 nm). The greater the hydrophilicity and particle size, the worse the cleanability (Table 6) and the worse the stain resistance (Table 7). The particle size used herein is the volume average.

[0108] Notably, the stain resistance test results for paints 1-2, namely 33 / 35 and 24.5 / 35, respectively, are superior to the results for the commercial paints shown in Table 4, namely from 11.5 / 35 to 18.5 / 35. In addition, the red cooking wine stain occupied a large enough area for measurement with the spectrophotometer instrument, and the change between the unsoiled area and the soiled area was significantly lower than 2.0 CIE2000 units for resin 1 and slightly higher than 2.0 CIE2000 units for resin 2.

[0109] As discussed in commonly owned U.S. Patent No. 9,994,722, colors are close enough to one another to be the same color to a person when the color difference (Delta E) between the colors is less than or equal to about 2.0 CIE 2000 units, preferably less than about 1.0 CIE 2000 units or less than about 0.5 CIE 2000 units. Experiments have confirmed that the human eye cannot distinguish or can barely distinguish colors from one another that are within 2.0 CIE 2000 color difference units of one another.

[0110] Additional experiments were performed to compare AAEM crosslinking monomers to DAAM crosslinking monomers, and to compare copolymer resins having hydrophobic monomers to copolymer resins copolymerized from hydrophilic monomers. Tables 8A and 8B show the results of these additional experiments. Paints 3-8 had an eggshell gloss.

[0111] Table 8A

[0112]

[0113]

[0114] Table 8B

[0115]

[0116] The experimental results shown in Tables 8A and 8B show that more hydrophobic resins (e.g., resins containing MMA / 2-EHA monomers) have lower stain resistance (paints 4, 5, and 6). More hydrophilic paints (e.g., paints containing MMA and BA monomers) have higher stain resistance.

[0117] Additional experiments were performed with the present paints 9 having a matte gloss relative to other commercial matte paints, as shown in Table 9.

[0118] Table 9.

[0119]

[0120] Table 9 shows further evidence that the matte gloss architectural compositions of the present invention, which highlight the matte gloss, are able to resist both hydrophobic and hydrophilic stains, and are better at resisting stains than the comparative commercial paints.

[0121] Although the stain resistance tests are described above, other standard tests performed and reported herein are described below.

[0122] The scrubability test results show the number of scrub cycles before failure, and the test was performed according to ASTM D2486 Method B.

[0123] Drying paint surfaces Glossor sheen indicates the glossiness or glassiness of a surface. Glossiness ranges from flat / matt to high gloss. The sheen of a surface can be described as the light reflection from the surface that is independent of color. To measure sheen, a beam of light is deflected from the surface at a specific angle into a receiver, as shown below and as discussed in http: / / www.paintinfo.com / mpi / approved / sheen.shtml, which is incorporated herein by reference in its entirety.

[0124]

[0125] The receiver measures the intensity of the light in sheen units. The equipment uses specially produced, polished glass or ceramic tiles for standardization. ASTM Method D 523 provides the procedure for performing this sheen test.

[0126] ASTM Method D 523 uses a 60° angle to compare surface sheen and determines if other angles such as 20° and 85° are needed. The 20° angle is used when the surface sample has a 60° sheen value greater than 70 sheen units; and the 85° angle is used if the 60° sheen value is less than 30 sheen units. Referring to the above diagram, the angle is measured from the vertical axis, for example, the 60° angle is measured from the vertical or 0° line, and the 60° angle is 30° above the surface being measured.

[0127] Generally, the term gloss is used to describe low angle sheen, for example, 85° from the vertical or 5° from the surface being measured. The 85° angle is preferred when measuring low sheen coatings and can generally be more accurate in indicating the transition between flat and eggshell. Steeper angles, such as 20°, are more often used for high sheen surfaces, such as automotive coatings.

[0128] Master Paint Institute (MPI) classifies the sheen gloss of paints as follows:

[0129] Paints with different sheen at different angles

[0130] Type of paint gloss 20° gloss 60° gloss 85° gloss High gloss 20-90 70-85+ - Semi-gloss 5-45 35-70 - Satin - 20-35 Min 35 Eggshell 10-25 10-35 Matte 0-10 Max 35

[0131] The higher the sheen value, the more shiny the surface.

[0132] As discussed in http: / / www.paintinfo.com / mpi / approved / sheen.shtml, the level of sheen of a coating is affected by its surface roughness. The protrusion of pigment or filler particles through the binder layer causes the diffraction of light and makes the coating appear dull. When the pigment or filler particles are covered by the binder layer, the coating surface is smoother and light rays that are incident at an angle are easily reflected. The sheen or reflected light can affect the visual color of the surface when viewed from different angles. This can be seen when coating surfaces that are to be tinted to the same color, but have different levels of sheen or sheen, are applied side by side on the same substrate. When viewed from directly above and perpendicular to the coating surface, and with the light directly behind, the closest color will be shown. Moving the field of view to an angle away from the perpendicular line or moving the light source will show the color shift due to the sheen difference.

[0133] The Tg or glass transition temperature can be easily calculated by Fox's equation, which sums the weight fraction of each monomer and the Tg of a polymer made entirely of that monomer, as discussed below. The calculated Tg includes the film forming monomers. Crosslinking monomers and any monomer whose contribution to the polymer is less than about 1.5 wt% and whose Tg is not widely available, such as a wet adhesion monomer, are omitted from the Tg calculation. Chain transfer agents are also omitted from the Tg calculation.

[0134] The aggregate Tg of a copolymer calculated by Fox's equation includes the individual Tg of each monomer that is copolymerized, as follows:

[0135] 1 / Tg agg = Wf1 / Tg1+ Wf2 / Tg2+ Wf x / Tg x ,

[0136] where

[0137] Tg agg is the aggregate Tg of the copolymer

[0138] Wf x is the weight fraction of each monomer x

[0139] Tg x is the Tg of a polymer made from the single monomer x

[0140] x is the number of monomers in the copolymer.

[0141] Differential scanning calorimetry (DSC) can also be used to measure Tg.

[0142] While the exemplary embodiments of the application disclosed herein clearly realize the above-mentioned objects, it is understood that those skilled in the art can design numerous modifications and other embodiments. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments which would come within the spirit and scope of the present application.

Claims

1. An aqueous architectural composition for forming a paint film on a substrate that is resistant to hydrophobic stains and hydrophilic stains, comprising: a film-forming latex resin for forming the paint film, an optional opacifying pigment, an organosilicon resin having a weight molecular weight greater than about 10,000 and less than about 100,000 Daltons, wherein the organosilicon resin comprises about 1 wt% to about 4 wt% of the aqueous architectural composition, wax microspheres having an average diameter (D 50 ), and comprising about 3 wt.% to about 9 wt.%, and at least one organic extender pigment.

2. The aqueous architectural composition of claim 1, wherein the organosilicon resin comprises about 1.25 wt% to about 3.5 wt% of the aqueous architectural composition.

3. The aqueous architectural composition of claim 2, wherein the organosilicon resin comprises about 1.5 wt% to about 3 wt% of the aqueous architectural composition.

4. The aqueous architectural composition of claim 1, wherein the weight molecular weight of the organosilicon resin is greater than about 15,000 Daltons.

5. The aqueous architectural composition of claim 4, wherein the weight molecular weight of the organosilicon resin is greater than about 20,000 Daltons.

6. The aqueous architectural composition of claim 5, wherein the weight molecular weight of the organosilicon resin is greater than about 25,000 Daltons.

7. The aqueous architectural composition of claim 1, wherein the weight molecular weight of the organosilicon resin is greater than about 30,000 Daltons.

8. The aqueous architectural composition of claim 1, wherein the wax microspheres are polyethylene wax microspheres.

9. The aqueous architectural composition of claim 1, wherein the wax microspheres comprise about 3.5 wt% to about 8.5 wt% of the aqueous architectural composition.

10. The aqueous architectural composition of claim 9, wherein the wax microspheres comprise about 4 wt% to about 7.5 wt% of the aqueous architectural composition.

11. The aqueous architectural composition of claim 1, wherein the film-forming latex resin comprises a phosphate monomer, wherein the phosphate monomer comprises 0.1 wt% to 1 wt%.

12. The aqueous architectural composition of claim 11, wherein the phosphate monomer comprises about 0.5 wt% to about 0.9 wt%.

13. The aqueous architectural composition of claim 12, wherein the phosphate monomer comprises about 0.6 wt% to about 0.8 wt%.

14. The aqueous architectural composition of claim 1, wherein the film-forming latex resin is substantially free of a wax seeded latex.

15. The aqueous architectural composition of claim 1, wherein the film-forming latex resin comprises a (meth)acrylate monomer.

16. The aqueous architectural composition of claim 1, wherein the film-forming latex resin comprises a vinyl and a (meth)acrylate monomer.

17. The aqueous architectural composition of claim 1, wherein the Tg of the film-forming latex resin ranges from 0°C to 50°C as calculated by the Flory Fox equation.

18. The aqueous architectural composition of claim 17, wherein the Tg of the film-forming latex resin ranges from 0°C to 30°C, or 2.5°C to 27.5°C, or 5°C to 25°C.

19. The aqueous architectural composition of claim 1, further comprising a fluorosurfactant.

20. The aqueous architectural composition of claim 1, further comprising a Gemini surfactant, a polyether-siloxane surfactant, and / or a neutralized alcohol phosphate ester type surfactant.

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